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National Trends, 2005 – 2011: Adverse-event Rates Declined among Patients Hospitalized for Acute Myocardial Infarction or Congestive Heart Failure

Posted in Acute Myocardial Infarction, Cardiac and Cardiovascular Surgical Procedures, Cardiovascular Research, Congenital Heart Disease, Frontiers in Cardiology and Cardiovascular Disorders, Health Economics and Outcomes Research, Health Law & Patient Safety, Origins of Cardiovascular Disease, PCI on February 4, 2014| Leave a Comment »

National Trends, 2005 – 2011: Adverse-event Rates Declined among Patients Hospitalized for Acute Myocardial Infarction or Congestive Heart Failure

 

Reporter: Aviva Lev-Ari, PhD, RN

UPDATED on July 25, 2018

 

Improving Safety for Hospitalized PatientsMuch Progress but Many Challenges Remain

Richard Kronick, PhD1,2; Sharon Arnold, PhD2; Jeffrey Brady, MD, MPH2
Author Affiliations
JAMA. 2016;316(5):489-490. doi:10.1001/jama.2016.7887

 

Agency for Healthcare Research and Quality Department of Health and Human Services (HHSA290201200003C), and a grant from the Center for Cardiovascular Outcomes Research at Yale University, National Heart, Lung, and Blood Institute (U01HL105270-04, to Dr. Krumholz)  funded the Study and concluded that:

From 2005 through 2011, adverse-event rates declined substantially among patients hospitalized for acute myocardial infarction or congestive heart failure but not among those hospitalized for pneumonia or conditions requiring surgery.

National Trends in Patient Safety for Four Common Conditions, 2005–2011

Yun Wang, Ph.D., Noel Eldridge, M.S., Mark L. Metersky, M.D., Nancy R. Verzier, M.S.N., Thomas P. Meehan, M.D., M.P.H., Michelle M. Pandolfi, M.S.W., M.B.A., JoAnne M. Foody, M.D., Shih-Yieh Ho, Ph.D., M.P.H., Deron Galusha, M.S., Rebecca E. Kliman, M.P.H., Nancy Sonnenfeld, Ph.D., Harlan M. Krumholz, M.D., and James Battles, Ph.D.

N Engl J Med 2014; 370:341-351 January 23, 2014DOI: 10.1056/NEJMsa1300991

BACKGROUND

Changes in adverse-event rates among Medicare patients with common medical conditions and conditions requiring surgery remain largely unknown.

METHODS

We used Medicare Patient Safety Monitoring System data abstracted from medical records on 21 adverse events in patients hospitalized in the United States between 2005 and 2011 for acute myocardial infarction, congestive heart failure, pneumonia, or conditions requiring surgery. We estimated trends in the rate of occurrence of adverse events for which patients were at risk, the proportion of patients with one or more adverse events, and the number of adverse events per 1000 hospitalizations.

RESULTS

The study included 61,523 patients hospitalized for acute myocardial infarction (19%), congestive heart failure (25%), pneumonia (30%), and conditions requiring surgery (27%). From 2005 through 2011, among patients with acute myocardial infarction, the rate of occurrence of adverse events declined from 5.0% to 3.7% (difference, 1.3 percentage points; 95% confidence interval [CI], 0.7 to 1.9), the proportion of patients with one or more adverse events declined from 26.0% to 19.4% (difference, 6.6 percentage points; 95% CI, 3.3 to 10.2), and the number of adverse events per 1000 hospitalizations declined from 401.9 to 262.2 (difference, 139.7; 95% CI, 90.6 to 189.0). Among patients with congestive heart failure, the rate of occurrence of adverse events declined from 3.7% to 2.7% (difference, 1.0 percentage points; 95% CI, 0.5 to 1.4), the proportion of patients with one or more adverse events declined from 17.5% to 14.2% (difference, 3.3 percentage points; 95% CI, 1.0 to 5.5), and the number of adverse events per 1000 hospitalizations declined from 235.2 to 166.9 (difference, 68.3; 95% CI, 39.9 to 96.7). Patients with pneumonia and those with conditions requiring surgery had no significant declines in adverse-event rates.

CONCLUSIONS

From 2005 through 2011, adverse-event rates declined substantially among patients hospitalized for acute myocardial infarction or congestive heart failure but not among those hospitalized for pneumonia or conditions requiring surgery. (Funded by the Agency for Healthcare Research and Quality and others.)

SOURCE

http://www.nejm.org/doi/full/10.1056/NEJMsa1300991?query=cardiology

Address reprint requests to Dr. Wang at the Department of Biostatistics, Harvard School of Public Health, SPH2, Rm. 437F, 655 Huntington Ave., Boston, MA 02115, or at yunwang@hsph.harvard.edu; or to Mr. Eldridge at the Center for Quality Improvement and Patient Safety, Agency for Healthcare Research and Quality, Rockville, MD 20850, or at noel.eldridge@ahrq.hhs.gov.

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Preserved vs Reduced Ejection Fraction: Available and Needed Therapies

Posted in Cardiomyopathy, Cardiovascular Research, Congenital Heart Disease, Electrophysiology, Frontiers in Cardiology and Cardiovascular Disorders, HTN, Myocardial metabolism, Myocardial ischemia, myocardial perfusion, Myocardial adenine nucleotide metabolism, Origins of Cardiovascular Disease, Pharmacotherapy of Cardiovascular Disease on February 3, 2014| Leave a Comment »

Preserved vs Reduced Ejection Fraction: Available and Needed Therapies

Reporter: Aviva Lev-Ari, PhD, RN

 

Ejection Fraction Heart Failure Measurement

Updated:Jul 9,2013

The ejection fraction (EF) is an important measurement in determining how well your heart is pumping out blood and in diagnosing and tracking heart failure.

A significant proportion of patients with heart failure happen to have a normal ventricular ejection fraction at echocardiography during examination. Previously called diastolic heart failure, it is nowadays referred to as heart failure with normal ejection fraction (HFNEF) or HF with preserved ejection fraction.

  1. Perserved ejection fraction (HFpEF) – also referred to as diastolic heart failure.  The heart muscle contracts normally but the ventricles do not relax as they should during ventricular filling (or when the ventricles relax).
  2. Reduced ejection fraction (HFREF) – also referred to as systolic heart failure.  The heart muscle does not contract effectively and less oxygen-rich blood is pumped out to the body.

What it is?
A measurement of how much blood the left ventricle pumps out with each contraction.

What it means.
An ejection fraction of 60 percent means that 60 percent of the total amount of blood in the left ventricle is pushed out with each heartbeat.

What’s normal?

  • A normal heart’s ejection fraction may be between 55 and 70.
  • You can have a normal ejection fraction reading and still have heart failure. If the heart muscle has become so thick and stiff that the ventricle holds a smaller-than-usual volume of blood, it might still seem to pump out a normal percentage of the blood that enters it. In reality, though, the total amount of blood pumped isn’t enough to meet your body’s needs.

What’s too low?

  • A measurement under 40 may be evidence of heart failure or cardiomyopathy.
  • An EF between 40 and 55 indicates damage, perhaps from a previous heart attack, but it may not indicate heart failure.
  • In severe cases, EF can be very low.

What’s too high?
EF higher than 75 percent may indicate a heart condition like hypertrophic cardiomyopathy.

Tests for measuring EF:

SOURCE
http://www.heart.org/HEARTORG/Conditions/HeartFailure/SymptomsDiagnosisofHeartFailure/Ejection-Fraction-Heart-Failure-Measurement_UCM_306339_Article.jsp

 

February 03, 2014

Both drug and device therapies have been shown to improve the outlook for patients with heart failure and reduced ejection fraction, but three leading cardiologists point to the lack of proven treatments for the other half of heart failure patients — those with preserved ejection fraction.

VIEW VIDEO

http://www.medpagetoday.com/HOTTOPICSWhatworksWhatDoesnt/special-reports/SpecialReports-Videos/394

SOURCE

From: MedPage Today <daily.headlines@medpagetoday.com>
To: <avivalev-ari@alum.berkeley.edu>

Heart Failure With Preserved Ejection Fraction

Circulation.2011; 124: e540-e543doi: 10.1161/​CIRCULATIONAHA.111.071696

 

  1. James E. Udelson, MD

+Author Affiliations


  1. From the Division of Cardiology and the CardioVascular Center, Tufts Medical Center, Boston, MA.
  1. Correspondence to James E. Udelson, MD, Tufts Medical Center, 800 Washington St, Box 70, Boston, MA 02111. E-mail judelson@tuftsmedicalcenter.org

 

Key Words:

It is now well established that among patients with the clinical syndrome of heart failure (HF), approximately half have preserved systolic function, known most commonly as heart failure with preserved ejection fraction (HFpEF). Although originally considered to be predominantly a syndrome that pathophysiologically involves abnormalities in diastolic function (relaxation and/or stiffness), ongoing investigation suggests that, although diastolic abnormalities may be present in many patients, other aspects of pathophysiology likely also contribute to symptoms.

Many recent articles have continued to explore aspects of this fascinating clinical syndrome. This review will summarize advances in understanding of the HFpEF syndrome, focusing on epidemiology, pathophysiology, and therapeutics.

Pathophysiology

Controversy continues regarding the prevalence of true abnormities of myocardial diastolic function in the syndrome of HFpEF. In a comprehensive invasive and noninvasive hemodynamic study in a group of highly selected patients with hemodynamically confirmed HFpEF, Prasad et al7 reported that compared with age-matched referent controls, increased static ventricular stiffness was not a universal finding in patients with HFpEF, although LV relaxation as assessed by tissue Doppler was consistently abnormal.

Substantial and growing attention has been given to the role of the cardiac interstitium in the pathophysiology of HFpEF. Zile and colleagues8 examined a panel of biomarkers for ability to discriminate symptomatic HFpEF from those with asymptomatic LV hypertrophy. This study showed that a panel of plasma biomarkers reflecting changes in extracellular matrix fibrillar collagen synthesis and degradation predicted the presence of HFpEF with an area under the curve of 0.79 and was more powerful than using N-terminal pro–B-type natriuretic peptide or clinical variables. Consistent with these findings, investigators from the Cardiovascular Health Study reported that biomarkers reflecting myocardial fibrosis, including carboxyl-terminal peptide of procollagen type I, carboxyl-terminal telopeptide of collagen type I, and amino-terminal peptide of procollagen type III, are significantly elevated in elderly patients with HFpEF and indeed are also elevated in those with systolic HF.9 Krum et al10 reported on a substudy from I-PRESERVE showing that increased baseline plasma levels of all collagen markers were associated with the I-PRESERVE primary outcome end point, although the relationship was not significant in a multivariable model. In a comprehensive human study, Westermann and colleagues11 interrogated the influence of cardiac inflammation on extracellular matrix remodeling in patients with HFpEF. Using endomyocardial biopsy samples to isolate primary human cardiac fibroblasts, the authors interrogated the gene expression of extracellular matrix proteins after stimulation with transforming growth factor-β. They reported an increase of cardiac collagen accompanied by a decrease in the collagenase system of the heart, as well as a correlation between cardiac collagen, inflammatory cells, and diastolic dysfunction. They concluded that inflammation contributes to diastolic abnormalities in HFpEF by stimulating extracellular matrix accumulation. All of these data suggest that the interstitium may be a promising therapeutic target if specific therapies can be deployed.

Although abnormalities in myocardial diastolic properties have been the focus of pathophysiological studies in patients with HFpEF in the past, many recent investigations have examined other structural and functional contributors. Kurt and colleagues12reported that HFpEF patients have similar LV mass and left atrial volume in comparison with patients with LV hypertrophy who are not in HF, although a measure of left atrial strain was reduced, and left atrial stiffness was useful in discriminating patients with HFpEF from those with LV hypertrophy without HF symptoms.

Several studies examined pathophysiology in HFpEF patients during exercise stress, which is when most patients have symptoms. Phan and colleagues13 reported that chronotropic incompetence, as measured by the percentage of the heart rate reserve used during maximal exercise, was more commonly present in patients with HFpEF compared with referent controls, as was abnormal heart rate recovery. Using dobutamine stress echocardiography with color tissue Doppler imaging, Chattopadhyay et al14 reported evidence of impaired diastolic reserve during stress, as well as stress-induced increase in the LV end-diastolic pressure, likely resulting in exercise intolerance because 6-minute walk distance was inversely correlated with the measures of diastolic function at rest and stress. Borlaug and colleagues15 examined hemodynamic responses to stress as a potential diagnostic approach in patients with exertional dyspnea, in whom making a specific diagnosis may be challenging. The investigators studied patients with exertional dyspnea, preserved EF, normal brain natriuretic peptide levels, and normal resting hemodynamics. Exercise-induced elevation in pulmonary capillary wedge pressure was used to define HFpEF and was associated with blunted increases in heart rate and cardiac output and blunted systemic vasodilation. An exercise pulmonary artery systolic pressure ≥45 mm Hg identified HFpEF with 96% sensitivity and 95% specificity. These data suggest that patients who present a challenge for specific diagnosis should undergo an exercise hemodynamic study.

Two studies examined clinical or echocardiographic variables that might be useful in estimating LV filling pressures in patients with HFpEF. Drazner et al16 reported that right atrial pressures often reflected left-sided filling pressures in HFpEF, suggesting that estimation of jugular venous pressure could be used to assess volume status. However, the echocardiographic indexes E/e′ and E/Vp did not appear to reliably track changes in left-sided filling pressures in patients with HFpEF.17

Studies using translational models explored the underlying mechanism of the transition from compensated LV hypertrophy to a state of HF. In a transverse aortic constriction model adding mineralocorticoid (deoxycorticosterone acetate) excess, Mohammed et al18reported that mice treated with deoxycorticosterone acetate showed progressive activation of markers of oxidative stress but no evidence of mineralocorticoid receptor–dependent gene transcription. They concluded that pressure-overload hypertrophy sensitizes the heart to mineralocorticoid excess and that the transition to HF with preserved EF is associated with mechanisms independent of mineralocorticoid receptor–dependent gene transcription. In a study of cardiac energy metabolism in which Dahl salt-sensitive rats fed a high-salt diet were used to drive a transition from compensated LV hypertrophy to HF, Kato and colleagues19 reported that glucose uptake increased with LV hypertrophy and further increased at the HF stage, with decreased fatty acid uptake and corresponding changes in gene expression related to the metabolic pathways as well as mitochondrial function with the onset of HF. Dichloroacetate, which enhances glucose oxidation, attenuated the transition to HF, associated with increased energy reserves and reduced oxidative stress. The data from these models suggest potential therapeutic directions for the future, although mineralocorticoid receptor antagonism is already under comprehensive study.

Therapeutics

As noted, large randomized trials in broad populations of patients with HFpEF in which agents such as angiotensin receptor blockers were used have generally shown neutral results. Smaller trials continue to explore potential therapeutic directions for this challenging-to-manage syndrome. Kitzman and colleagues20 randomized 71 elderly HFpEF patients with compensated symptoms and controlled blood pressure into a 12-month follow-up double-blind trial of enalapril 20 mg/d versus placebo.

There was no effect of the angiotensin-converting enzyme inhibitor on

  • the primary end point of peak exercise oxygen consumption and
  • no effect on multiple secondary end points including 6-minute walk distance,
  • aortic distensibility,
  • LV mass, or
  • neurohormones.

The findings are consistent with the longer-term natural history outcomes of angiotensin receptor blocker trials.

Many of the same authors examined a nonpharmacological approach in a 16-week randomized study of supervised exercise training in 53 elderly patients with HFpEF.21The primary outcome was peak exercise oxygen uptake, which increased significantly in the exercise group compared with the control group (2.3±2.2 versus −0.3±2.1 mL/kg per meter; P=0.0002). Many secondary end points were also improved, including exercise time, 6-minute walk distance, and ventilatory anaerobic threshold. In contrast to some trials of exercise training, a key to the favorable results of this study may have been the good compliance with the exercise training regimen among the enrolled patients. These important data suggest an important therapeutic direction.

Favorable results were also seen in a small study involving an important subgroup of HFpEF patients, those with pulmonary hypertension. Guazzi and coworkers22 randomized 44 such patients to sildenafil at a dose of 50 mg 3 times per day or to placebo for 6 months. At the end of the trial, sildenafil was associated with decreased mean pulmonary artery and reduced right atrial pressure and improved right ventricular function. They also reported reduced lung water content and improved alveolar-capillary gas conductance, as well as improved measure of left-sided systolic and diastolic cardiac function. Results were maintained at 12 months.

Hence, although large trials using neurohormonal antagonists that have been favorable in HF with reduced EF have not shown favorable results in HFpEF, these early studies suggest promising therapeutic directions to explore. Such studies also enhance our understanding of pathophysiology and point the way to larger and more definitive investigations.

SOURCE
REFERENCES
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Calcium and Cardiovascular Diseases: A Series of Twelve Articles in Advanced Cardiology

Posted in Acute Myocardial Infarction, Atherogenic Processes & Pathology, Best evidence, Ca2+ triggered activation, Calcium, Calcium Signaling, Calmodulin Kinase and Contraction, Cardiomyopathy, Cardiovascular Research, Congenital Heart Disease, Electrophysiology, Frontiers in Cardiology and Cardiovascular Disorders, Genome Biology, HTN, Myocardial Metabolism, Origins of Cardiovascular Disease, Pharmacotherapy of Cardiovascular Disease, Pre-Clinical Animal Model Development, Translational Effectiveness, Translational Research, Translational Science on January 28, 2014| Leave a Comment »

Calcium and Cardiovascular Diseases: A Series of Twelve Articles in Advanced Cardiology

Curator: Aviva Lev-Ari, PhD, RN

UPDATED on 7/18/2021

ER

IMAGE SOURCE:

Claudio A. Hetz. Antioxidants & Redox Signaling.Dec 2007.

2345-2356. http://doi.org/10.1089/ars.2007.1793

FIG. 3. Regulation of ER calcium homeostasis by the BCL-2 protein family. Different anti- and proapoptotic members of the BCL-2 family of proteins are located at the ER membrane, where they have an important role regulating ER calcium content. BCL-2 and BCL-XL interact with the IP3R calcium channel, modulating its activity. BCL-2 has been shown to increase ER calcium leak through the IP3R because of an increase on its phosphorylation levels.

BAX and BAK have the opposite effect on ER calcium content, a function that may be further modulated by BH3-only proteins (such as PUMA and BIK). In addition, the activity of BCL-2 at the ER membrane is regulated by phosphorylation. JNK phosphorylates BCL-2, decreasing its antiapoptotic activity and increasing ER calcium content, whereas the phosphatase PP2A decreases this phosphorylation through a direct interaction. Alternatively, ER stress activates the IRE1/JNK pathway that may alter the activity of BCL-2 at the ER membrane. BI-1 is also located at the ER membrane, where it regulates calcium homeostasis.

CONCLUSIONS AND THERAPEUTIC PERSPECTIVES

I have summarized different pieces of evidence suggesting that the BCL-2 family of proteins has evolved to regulate multiple processes involved in cell survival under stress conditions. The global view of the current state of the field indicates that the BCL-2–related proteins are not only the “death gateway” keeper (as upstream regulators of caspases), but they also have multiple functions in essential processes for the cell. BCL-2–related proteins are particularly important in the physiologic maintenance of the ER, where they operate as

(a) a calcium rheostat,

(b) modulators of the UPR,

(c) regulators of ER network structure, and

(d) regulators of autophagy.

In addition, examples of a role of the BCL-2 family of proteins in cell-cycle regulation (87, 113), DNA damage responses (37, 114), and glucose/energy metabolism (16) are available, strongly supporting the notion that the BCL-2 protein family is a multifunctional group of proteins that, under normal conditions, participate in essential cellular process. In doing so, the BCL-2 protein family may represent specialized stress sentinels that actively participate in essential processes, allowing a constant homeostatic “quality control.” In response to irreversible cellular damage, particular BCL-2 family members may turn into direct activators of apoptosis.

Mutations in specific genes are responsible for a variety of neurologic disorders due to the misfolding and accumulation of abnormal protein aggregates in the brain. In many of these diseases, it has been suggested that alteration in the homeostasis of the ER contributes significantly to neuronal dysfunction.

These diseases include Parkinson’s disease (32, 84), Alzheimer’s disease (22), prion diseases (27, 28, 31), amyotrophic lateral sclerosis (ALS) (97), Huntington’s disease (63, 90) and many others (see list of diseases in 86). Consequently, the first steps in the death pathways downstream of ER stress represent important therapeutic targets. In this line of thinking, pharmacologic manipulation of the activity of the BCL-2 protein family may have beneficial consequences to treat these fatal diseases. Different small molecules and synthetic peptides are currently available with proven therapeutic applications in mouse disease models, including BCL-2 inhibitors (71), BAX channel inhibitors (29), BAX/BAK activator peptides (100, 101) and many others (see reviews in 52, 79). These drugs may be used as pharmacologic tools to manipulate the activity of stress-signaling pathways regulated by the BCL-2 protein family (i.e., autophagy, calcium metabolism, or the UPR) and their possible role in pathologic conditions.

SOURCE

Claudio A. Hetz.Antioxidants & Redox Signaling.Dec 2007.

2345-2356. http://doi.org/10.1089/ars.2007.1793

  • Published in Volume: 9 Issue 12: November 2, 2007
  • Online Ahead of Print: September 13, 2007

UPDATED on 7/1/2015

We add the following to this series:

Part XIII 

Ca2+-Stimulated Exocytosis:  The Role of Calmodulin and Protein Kinase C in Ca2+ Regulation of Hormone and Neurotransmitter
Larry H Bernstein, MD, FCAP and Aviva Lev-Ari, PhD, RN

Part I:

Identification of Biomarkers that are Related to the Actin Cytoskeleton

Larry H Bernstein, MD, FCAP

Part II:

Role of Calcium, the Actin Skeleton, and Lipid Structures in Signaling and Cell Motility

Larry H. Bernstein, MD, FCAP, Stephen Williams, PhD and Aviva Lev-Ari, PhD, RN

Part III:

Renal Distal Tubular Ca2+ Exchange Mechanism in Health and Disease

Larry H. Bernstein, MD, FCAP, Stephen J. Williams, PhD
 and Aviva Lev-Ari, PhD, RN

Part IV:

The Centrality of Ca(2+) Signaling and Cytoskeleton Involving Calmodulin Kinases and Ryanodine Receptors in Cardiac Failure, ArterialSmooth Muscle, Post-ischemic Arrhythmia, Similarities and Differences, and Pharmaceutical Targets

Larry H Bernstein, MD, FCAP, Justin Pearlman, MD, PhD, FACC and Aviva Lev-Ari, PhD, RN

Part V:

Heart, Vascular Smooth Muscle, Excitation-Contraction Coupling (E-CC), Cytoskeleton, Cellular Dynamics and Ca2 Signaling

Larry H Bernstein, MD, FCAP, Justin Pearlman, MD, PhD, FACC and Aviva Lev-Ari, PhD, RN

Part VI:

Calcium Cycling (ATPase Pump) in Cardiac Gene Therapy: Inhalable Gene Therapy for Pulmonary Arterial Hypertension and Percutaneous Intra-coronary Artery Infusion for Heart Failure: Contributions by Roger J. Hajjar, MD

Aviva Lev-Ari, PhD, RN

Part VII:

Cardiac Contractility & Myocardium Performance: Ventricular Arrhythmias and Non-ischemic Heart Failure – Therapeutic Implications for Cardiomyocyte Ryanopathy (Calcium Release-related Contractile Dysfunction) and Catecholamine Responses

Justin Pearlman, MD, PhD, FACC, Larry H Bernstein, MD, FCAP and Aviva Lev-Ari, PhD, RN

Part VIII

Disruption of Calcium Homeostasis: Cardiomyocytes and Vascular Smooth Muscle Cells: The Cardiac and Cardiovascular Calcium Signaling Mechanism – Part VIII

Justin Pearlman, MD, PhD, FACC, Larry H Bernstein, MD, FCAP and Aviva Lev-Ari, PhD, RN

Part IX

Calcium-Channel Blockers, Calcium Release-related Contractile Dysfunction (Ryanopathy) and Calcium as Neurotransmitter Sensor – Part IX

Justin Pearlman, MD, PhD, FACC, Larry H Bernstein, MD, FCAP and Aviva Lev-Ari, PhD, RN

Part X

Synaptotagmin functions as a Calcium Sensor: How Calcium Ions Regulate the fusion of vesicles with cell membranes during Neurotransmission – Part X

Larry H Bernstein, MD, FCAP and Aviva Lev-Ari, PhD, RN

Part XI

Sensors and Signaling in Oxidative Stress – Part XI

Larry H. Bernstein, MD, FCAP

Part XII

Atherosclerosis Independence: Genetic Polymorphisms of Ion Channels Role in the Pathogenesis of Coronary Microvascular Dysfunction and Myocardial Ischemia (Coronary Artery Disease (CAD)) – Part XII

Larry H Bernstein, MD, FCAP and Aviva Lev-Ari, PhD,

Read Full Post »

Publications on Heart Failure by Prof. William Gregory Stevenson, M.D., BWH

Posted in Atherogenic Processes & Pathology, Cardiomyopathy, Cardiovascular Research, Congenital Heart Disease, Electrophysiology, Frontiers in Cardiology and Cardiovascular Disorders, Myocardial metabolism, Myocardial ischemia, myocardial perfusion, Myocardial adenine nucleotide metabolism, Origins of Cardiovascular Disease on January 13, 2014| Leave a Comment »

Publications on Heart Failure by Prof. William Gregory Stevenson, M.D., BWH

Reporter: Aviva Lev-Ari, PhD, RN

 

Prof. William Gregory Stevenson, M.D.

Title Professor of Medicine
Institution Brigham and Women’s Hospital
Department Medicine
Address Brigham and Women’s Hospital Cardiovascular 75 Francis St Boston MA 02115
Phone 617/732-7535
Fax 617/732-7134
  1. Givertz MM, Teerlink JR, Albert NM, Westlake Canary CA, Collins SP, Colvin-Adams M, Ezekowitz JA, Fang JC, Hernandez AF, Katz SD, Krishnamani R, Stough WG, Walsh MN, Butler J, Carson PE, Dimarco JP, Hershberger RE, Rogers JG, Spertus JA, Stevenson WG, Sweitzer NK, Tang WH, Starling RC. Acute decompensated heart failure: update on new and emerging evidence and directions for future research. J Card Fail. 2013 Jun; 19(6):371-89.
    View in: PubMed
  2. Tokuda M, Kojodjojo P, Tung S, Tedrow UB, Nof E, Inada K, Koplan BA, Michaud GF, John RM, Epstein LM, Stevenson WG. Acute failure of catheter ablation for ventricular tachycardia due to structural heart disease: causes and significance. J Am Heart Assoc. 2013; 2(3):e000072.
    View in: PubMed
  3. Ng J, Barbhaiya C, Chopra N, Reichlin T, Nof E, Tadros T, Stevenson WG, John RM. Automatic external defibrillators-friend or foe? Am J Emerg Med. 2013 Aug; 31(8):1292.e1-2.
    View in: PubMed
  4. Steven D, Sultan A, Reddy V, Luker J, Altenburg M, Hoffmann B, Rostock T, Servatius H, Stevenson WG, Willems S, Michaud GF. Benefit of pulmonary vein isolation guided by loss of pace capture on the ablation line: results from a prospective 2-center randomized trial. J Am Coll Cardiol. 2013 Jul 2; 62(1):44-50.
    View in: PubMed
  5. Kojodjojo P, Tokuda M, Bohnen M, Michaud GF, Koplan BA, Epstein LM, Albert CM, John RM, Stevenson WG, Tedrow UB. Electrocardiographic left ventricular scar burden predicts clinical outcomes following infarct-related ventricular tachycardia ablation. Heart Rhythm. 2013 Aug; 10(8):1119-24.
    View in: PubMed
  6. Nof E, Stevenson WG, Epstein LM, Tedrow UB, Koplan BA. Catheter Ablation of Atrial Arrhythmias After Cardiac Transplantation: Findings at EP Study Utility of 3-D Mapping and Outcomes. J Cardiovasc Electrophysiol. 2013 May; 24(5):498-502.
    View in: PubMed
  7. Michaud GF, Stevenson WG. Feeling a little loopy? J Cardiovasc Electrophysiol. 2013 May; 24(5):553-5.
    View in: PubMed
  8. Epstein AE, Dimarco JP, Ellenbogen KA, Estes NA, Freedman RA, Gettes LS, Gillinov AM, Gregoratos G, Hammill SC, Hayes DL, Hlatky MA, Newby LK, Page RL, Schoenfeld MH, Silka MJ, Stevenson LW, Sweeney MO, Tracy CM, Epstein AE, Darbar D, Dimarco JP, Dunbar SB, Estes NA, Ferguson TB, Hammill SC, Karasik PE, Link MS, Marine JE, Schoenfeld MH, Shanker AJ, Silka MJ, Stevenson LW, Stevenson WG, Varosy PD, Anderson JL, Jacobs AK, Halperin JL, Albert NM, Creager MA, Demets D, Ettinger SM, Guyton RA, Hochman JS, Kushner FG, Ohman EM, Stevenson W, Yancy CW. 2012 ACCF/AHA/HRS Focused Update Incorporated Into the ACCF/AHA/HRS 2008 Guidelines for Device-Based Therapy of Cardiac Rhythm Abnormalities: A Report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines and the Heart Rhythm Society. Circulation. 2013 Jan 22; 127(3):e283-352.
    View in: PubMed
  9. Tracy CM, Epstein AE, Darbar D, Dimarco JP, Dunbar SB, Mark Estes NA, Ferguson TB, Hammill SC, Karasik PE, Link MS, Marine JE, Schoenfeld MH, Shanker AJ, Silka MJ, Stevenson LW, Stevenson WG, Varosy PD, Epstein AE, Dimarco JP, Ellenbogen KA, Mark Estes NA, Freedman RA, Gettes LS, Marc Gillinov A, Gregoratos G, Hammill SC, Hayes DL, Hlatky MA, Kristin Newby L, Page RL, Schoenfeld MH, Silka MJ, Warner Stevenson L, Sweeney MO, Anderson JL, Jacobs AK, Halperin JL, Albert NM, Creager MA, Demets D, Ettinger SM, Guyton RA, Hochman JS, Kushner FG, Ohman EM, Stevenson W, Yancy CW. 2012 ACCF/AHA/HRS focused update of the 2008 guidelines for device-based therapy of cardiac rhythm abnormalities: A report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines. J Thorac Cardiovasc Surg. 2012 Dec; 144(6):e127-45.
    View in: PubMed
  10. John RM, Tedrow UB, Koplan BA, Albert CM, Epstein LM, Sweeney MO, Miller AL, Michaud GF, Stevenson WG. Ventricular arrhythmias and sudden cardiac death. Lancet. 2012 Oct 27; 380(9852):1520-9.
    View in: PubMed
  11. Tracy CM, Epstein AE, Darbar D, DiMarco JP, Dunbar SB, Estes NA, Ferguson TB, Hammill SC, Karasik PE, Link MS, Marine JE, Schoenfeld MH, Shanker AJ, Silka MJ, Stevenson LW, Stevenson WG, Varosy PD, Ellenbogen KA, Freedman RA, Gettes LS, Gillinov AM, Gregoratos G, Hayes DL, Page RL, Stevenson LW, Sweeney MO. 2012 ACCF/AHA/HRS focused update of the 2008 guidelines for device-based therapy of cardiac rhythm abnormalities: a report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines. Circulation. 2012 Oct 2; 126(14):1784-800.
    View in: PubMed
  12. Tracy CM, Epstein AE, Darbar D, Dimarco JP, Dunbar SB, Estes NA, Ferguson TB, Hammill SC, Karasik PE, Link MS, Marine JE, Schoenfeld MH, Shanker AJ, Silka MJ, Stevenson LW, Stevenson WG, Varosy PD. 2012 ACCF/AHA/HRS Focused Update of the 2008 Guidelines for Device-Based Therapy of Cardiac Rhythm Abnormalities: a report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines. Heart Rhythm. 2012 Oct; 9(10):1737-53.
    View in: PubMed
  13. Tokuda M, Tedrow UB, Kojodjojo P, Inada K, Koplan BA, Michaud GF, John RM, Epstein LM, Stevenson WG. Catheter ablation of ventricular tachycardia in nonischemic heart disease. Circ Arrhythm Electrophysiol. 2012 Oct 1; 5(5):992-1000.
    View in: PubMed
  14. John RM, Stevenson WG. Ventricular arrhythmias in patients with implanted cardioverter defibrillators. Trends Cardiovasc Med. 2012 Oct; 22(7):169-73.
    View in: PubMed
  15. Waldo AL, Wilber DJ, Marchlinski FE, Stevenson WG, Aker B, Boo LM, Jackman WM. Safety of the open-irrigated ablation catheter for radiofrequency ablation: safety analysis from six clinical studies. Pacing Clin Electrophysiol. 2012 Sep; 35(9):1081-9.
    View in: PubMed
  16. Tedrow UB, Sobieszczyk P, Stevenson WG. Transvenous ethanol ablation of ventricular tachycardia. Heart Rhythm. 2012 Oct; 9(10):1640-1.
    View in: PubMed
  17. Stevenson WG, Tedrow UB. Ablation for ventricular tachycardia during stable sinus rhythm. Circulation. 2012 May 8; 125(18):2175-7.
    View in: PubMed
  18. Wissner E, Stevenson WG, Kuck KH. Catheter ablation of ventricular tachycardia in ischaemic and non-ischaemic cardiomyopathy: where are we today? A clinical review. Eur Heart J. 2012 Jun; 33(12):1440-50.
    View in: PubMed
  19. Vollmann D, Stevenson WG, Lüthje L, Sohns C, John RM, Zabel M, Michaud GF. Misleading long post-pacing interval after entrainment of typical atrial flutter from the cavotricuspid isthmus. J Am Coll Cardiol. 2012 Feb 28; 59(9):819-24.
    View in: PubMed
  20. Stevenson WG, Hernandez AF, Carson PE, Fang JC, Katz SD, Spertus JA, Sweitzer NK, Tang WH, Albert NM, Butler J, Westlake Canary CA, Collins SP, Colvin-Adams M, Ezekowitz JA, Givertz MM, Hershberger RE, Rogers JG, Teerlink JR, Walsh MN, Stough WG, Starling RC. Indications for cardiac resynchronization therapy: 2011 update from the Heart Failure Society of America Guideline Committee. J Card Fail. 2012 Feb; 18(2):94-106.
    View in: PubMed
  21. Inada K, Tokuda M, Roberts-Thomson KC, Steven D, Seiler J, Tedrow UB, Stevenson WG. Relation of high-pass filtered unipolar electrograms to bipolar electrograms during ventricular mapping. Pacing Clin Electrophysiol. 2012 Feb; 35(2):157-63.
    View in: PubMed
  22. Albert CM, Chen PS, Anderson ME, Cain ME, Fishman GI, Narayan SM, Olgin JE, Spooner PM, Stevenson WG, Van Wagoner DR, Packer DL. Full report from the first annual Heart Rhythm Society Research Forum: a vision for our research future, “dream, discover, develop, deliver”. Heart Rhythm. 2011 Dec; 8(12):e1-12.
    View in: PubMed
  23. Stevenson WG, John RM. Ventricular arrhythmias in patients with implanted defibrillators. Circulation. 2011 Oct 18; 124(16):e411-4.
    View in: PubMed
  24. Tokuda M, Sobieszczyk P, Eisenhauer AC, Kojodjojo P, Inada K, Koplan BA, Michaud GF, John RM, Epstein LM, Sacher F, Stevenson WG, Tedrow UB. Transcoronary ethanol ablation for recurrent ventricular tachycardia after failed catheter ablation: an update. Circ Arrhythm Electrophysiol. 2011 Dec; 4(6):889-96.
    View in: PubMed
  25. John RM, Stevenson WG. Catheter-based ablation for ventricular arrhythmias. Curr Cardiol Rep. 2011 Oct; 13(5):399-406.
    View in: PubMed
  26. Martinek M, Stevenson WG, Inada K, Tokuda M, Tedrow UB. QRS characteristics fail to reliably identify ventricular tachycardias that require epicardial ablation in ischemic heart disease. J Cardiovasc Electrophysiol. 2012 Feb; 23(2):188-93.
    View in: PubMed
  27. Asimaki A, Tandri H, Duffy ER, Winterfield JR, Mackey-Bojack S, Picken MM, Cooper LT, Wilber DJ, Marcus FI, Basso C, Thiene G, Tsatsopoulou A, Protonotarios N, Stevenson WG, McKenna WJ, Gautam S, Remick DG, Calkins H, Saffitz JE. Altered desmosomal proteins in granulomatous myocarditis and potential pathogenic links to arrhythmogenic right ventricular cardiomyopathy. Circ Arrhythm Electrophysiol. 2011 Oct; 4(5):743-52.
    View in: PubMed
  28. Wijnmaalen AP, Roberts-Thomson KC, Steven D, Klautz RJ, Willems S, Schalij MJ, Stevenson WG, Zeppenfeld K. Catheter ablation of ventricular tachycardia after left ventricular reconstructive surgery for ischemic cardiomyopathy. Heart Rhythm. 2012 Jan; 9(1):10-7.
    View in: PubMed
  29. Stevenson WG, Couper GS. A surgical option for ventricular tachycardia caused by nonischemic cardiomyopathy. Circ Arrhythm Electrophysiol. 2011 Aug; 4(4):429-31.
    View in: PubMed
  30. Tokuda M, Kojodjojo P, Epstein LM, Koplan BA, Michaud GF, Tedrow UB, Stevenson WG, John RM. Outcomes of cardiac perforation complicating catheter ablation of ventricular arrhythmias. Circ Arrhythm Electrophysiol. 2011 Oct; 4(5):660-6.
    View in: PubMed
  31. Kosmidou I, Inada K, Seiler J, Koplan B, Stevenson WG, Tedrow UB. Role of repeat procedures for catheter ablation of postinfarction ventricular tachycardia. Heart Rhythm. 2011 Oct; 8(10):1516-22.
    View in: PubMed
  32. Bohnen M, Stevenson WG, Tedrow UB, Michaud GF, John RM, Epstein LM, Albert CM, Koplan BA. Incidence and predictors of major complications from contemporary catheter ablation to treat cardiac arrhythmias. Heart Rhythm. 2011 Nov; 8(11):1661-6.
    View in: PubMed
  33. Wijnmaalen AP, Stevenson WG, Schalij MJ, Field ME, Stephenson K, Tedrow UB, Koplan BA, Putter H, Epstein LM, Zeppenfeld K. ECG identification of scar-related ventricular tachycardia with a left bundle-branch block configuration. Circ Arrhythm Electrophysiol. 2011 Aug; 4(4):486-93.
    View in: PubMed
  34. Steven D, Roberts-Thomson KC, Inada K, Seiler J, Koplan BA, Tedrow UB, Sweeney MO, Epstein LE, Stevenson WG. Long-term follow-up in patients with presumptive Brugada syndrome treated with implanted defibrillators. J Cardiovasc Electrophysiol. 2011 Oct; 22(10):1115-9.
    View in: PubMed
  35. Bohnen M, Shea JB, Michaud GF, John R, Stevenson WG, Epstein LM, Tedrow UB, Albert C, Koplan BA. Quality of life with atrial fibrillation: do the spouses suffer as much as the patients? Pacing Clin Electrophysiol. 2011 Jul; 34(7):804-9.
    View in: PubMed
  36. Fuster V, Rydén LE, Cannom DS, Crijns HJ, Curtis AB, Ellenbogen KA, Halperin JL, Kay GN, Le Huezey JY, Lowe JE, Olsson SB, Prystowsky EN, Tamargo JL, Wann LS, Smith SC, Priori SG, Estes NA, Ezekowitz MD, Jackman WM, January CT, Lowe JE, Page RL, Slotwiner DJ, Stevenson WG, Tracy CM, Jacobs AK, Anderson JL, Albert N, Buller CE, Creager MA, Ettinger SM, Guyton RA, Halperin JL, Hochman JS, Kushner FG, Ohman EM, Stevenson WG, Tarkington LG, Yancy CW. 2011 ACCF/AHA/HRS focused updates incorporated into the ACC/AHA/ESC 2006 guidelines for the management of patients with atrial fibrillation: a report of the American College of Cardiology Foundation/American Heart Association Task Force on practice guidelines. Circulation. 2011 Mar 15; 123(10):e269-367.
    View in: PubMed
  37. Wann LS, Curtis AB, Ellenbogen KA, Estes NA, Ezekowitz MD, Jackman WM, January CT, Lowe JE, Page RL, Slotwiner DJ, Stevenson WG, Tracy CM, Fuster V, Rydén LE, Cannom DS, Crijns HJ, Curtis AB, Ellenbogen KA, Halperin JL, Kay GN, Le Heuzey JY, Lowe JE, Olsson SB, Prystowsky EN, Tamargo JL, Wann LS, Jacobs AK, Anderson JL, Albert N, Creager MA, Ettinger SM, Guyton RA, Halperin JL, Hochman JS, Kushner FG, Ohman EM, Stevenson WG, Yancy CW. 2011 ACCF/AHA/HRS focused update on the management of patients with atrial fibrillation (update on Dabigatran): a report of the American College of Cardiology Foundation/American Heart Association Task Force on practice guidelines. Circulation. 2011 Mar 15; 123(10):1144-50.
    View in: PubMed
  38. Wann LS, Curtis AB, Ellenbogen KA, Estes NA, Ezekowitz MD, Jackman WM, January CT, Lowe JE, Page RL, Slotwiner DJ, Stevenson WG, Tracy CM. 2011 ACCF/AHA/HRS focused update on the management of patients with atrial fibrillation (update on dabigatran): a report of the American College of Cardiology Foundation/American Heart Association Task Force on practice guidelines. J Am Coll Cardiol. 2011 Mar 15; 57(11):1330-7.
    View in: PubMed
  39. Wann LS, Curtis AB, Ellenbogen KA, Estes NA, Ezekowitz MD, Jackman WM, January CT, Lowe JE, Page RL, Slotwiner DJ, Stevenson WG, Tracy CM, Fuster V, Rydén LE, Cannom DS, Crijns HJ, Curtis AB, Ellenbogen KA, Halperin JL, Kay GN, Le Heuzey JY, Lowe JE, Olsson SB, Prystowsky EN, Tamargo JL, Wann LS, Jacobs AK, Anderson JL, Albert N, Creager MA, Ettinger SM, Guyton RA, Halperin JL, Hochman JS, Kushner FG, Ohman EM, Stevenson WG, Yancy CW. 2011 ACCF/AHA/HRS focused update on the management of patients with atrial fibrillation (update on dabigatran). A report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines. Heart Rhythm. 2011 Mar; 8(3):e1-8.
    View in: PubMed
  40. Dukkipati SR, d’Avila A, Soejima K, Bala R, Inada K, Singh S, Stevenson WG, Marchlinski FE, Reddy VY. Long-term outcomes of combined epicardial and endocardial ablation of monomorphic ventricular tachycardia related to hypertrophic cardiomyopathy. Circ Arrhythm Electrophysiol. 2011 Apr; 4(2):185-94.
    View in: PubMed
  41. Tedrow UB, Stevenson WG. Recording and interpreting unipolar electrograms to guide catheter ablation. Heart Rhythm. 2011 May; 8(5):791-6.
    View in: PubMed
  42. Wann LS, Curtis AB, January CT, Ellenbogen KA, Lowe JE, Estes NA, Page RL, Ezekowitz MD, Slotwiner DJ, Jackman WM, Stevenson WG, Tracy CM, Fuster V, Rydén LE, Cannom DS, Le Heuzey JY, Crijns HJ, Lowe JE, Curtis AB, Olsson SB, Ellenbogen KA, Prystowsky EN, Halperin JL, Tamargo JL, Kay GN, Wann LS, Jacobs AK, Anderson JL, Albert N, Hochman JS, Buller CE, Kushner FG, Creager MA, Ohman EM, Ettinger SM, Stevenson WG, Guyton RA, Tarkington LG, Halperin JL, Yancy CW. 2011 ACCF/AHA/HRS focused update on the management of patients with atrial fibrillation (Updating the 2006 Guideline): a report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines. J Am Coll Cardiol. 2011 Jan 11; 57(2):223-42.
    View in: PubMed
  43. Wann LS, Curtis AB, January CT, Ellenbogen KA, Lowe JE, Estes NA, Page RL, Ezekowitz MD, Slotwiner DJ, Jackman WM, Stevenson WG, Tracy CM, Fuster V, Rydén LE, Cannom DS, Le Heuzey JY, Crijns HJ, Lowe JE, Curtis AB, Olsson S, Ellenbogen KA, Prystowsky EN, Halperin JL, Tamargo JL, Kay GN, Wann LS, Jacobs AK, Anderson JL, Albert N, Hochman JS, Buller CE, Kushner FG, Creager MA, Ohman EM, Ettinger SM, Stevenson WG, Guyton RA, Tarkington LG, Halperin JL, Yancy CW. 2011 ACCF/AHA/HRS focused update on the management of patients with atrial fibrillation (Updating the 2006 Guideline): a report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines. Heart Rhythm. 2011 Jan; 8(1):157-76.
    View in: PubMed
  44. Wann LS, Curtis AB, January CT, Ellenbogen KA, Lowe JE, Estes NA, Page RL, Ezekowitz MD, Slotwiner DJ, Jackman WM, Stevenson WG, Tracy CM, Fuster V, Rydén LE, Cannom DS, Le Heuzey JY, Crijns HJ, Lowe JE, Curtis AB, Olsson S, Ellenbogen KA, Prystowsky EN, Halperin JL, Tamargo JL, Kay GN, Wann L, Jacobs AK, Anderson JL, Albert N, Hochman JS, Buller CE, Kushner FG, Creager MA, Ohman EM, Ettinger SM, Stevenson WG, Guyton RA, Tarkington LG, Halperin JL, Yancy CW. 2011 ACCF/AHA/HRS focused update on the management of patients with atrial fibrillation (updating the 2006 guideline): a report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines. Circulation. 2011 Jan 4; 123(1):104-23.
    View in: PubMed
  45. Stevenson WG, Asirvatham SJ. Teaching rounds in cardiac electrophysiology. Circ Arrhythm Electrophysiol. 2010 Dec; 3(6):563.
    View in: PubMed
  46. Rosman JZ, John RM, Stevenson WG, Epstein LM, Tedrow UB, Koplan BA, Albert CM, Michaud GF. Resetting criteria during ventricular overdrive pacing successfully differentiate orthodromic reentrant tachycardia from atrioventricular nodal reentrant tachycardia despite interobserver disagreement concerning QRS fusion. Heart Rhythm. 2011 Jan; 8(1):2-7.
    View in: PubMed
  47. Gautam S, John RM, Stevenson WG, Jain R, Epstein LM, Tedrow U, Koplan BA, McClennen S, Michaud GF. Effect of therapeutic INR on activated clotting times, heparin dosage, and bleeding risk during ablation of atrial fibrillation. J Cardiovasc Electrophysiol. 2011 Mar; 22(3):248-54.
    View in: PubMed
  48. Inada K, Seiler J, Roberts-Thomson KC, Steven D, Rosman J, John RM, Sobieszczyk P, Stevenson WG, Tedrow UB. Substrate characterization and catheter ablation for monomorphic ventricular tachycardia in patients with apical hypertrophic cardiomyopathy. J Cardiovasc Electrophysiol. 2011 Jan; 22(1):41-8.
    View in: PubMed
  49. Sacher F, Roberts-Thomson K, Maury P, Tedrow U, Nault I, Steven D, Hocini M, Koplan B, Leroux L, Derval N, Seiler J, Wright MJ, Epstein L, Haissaguerre M, Jais P, Stevenson WG. Epicardial ventricular tachycardia ablation a multicenter safety study. J Am Coll Cardiol. 2010 May 25; 55(21):2366-72.
    View in: PubMed
  50. Britton KA, Stevenson WG, Levy BD, Katz JT, Loscalzo J. Clinical problem-solving. The beat goes on. N Engl J Med. 2010 May 6; 362(18):1721-6.
    View in: PubMed
  51. Ross JJ, Britton KA, Desai AS, Stevenson WG. Interactive medical case. The beat goes on. N Engl J Med. 2010 Apr 15; 362(15):e53.
    View in: PubMed
  52. Tedrow UB, Stevenson WG. Arrhythmias: Catheter ablation for prevention of ventricular tachycardia. Nat Rev Cardiol. 2010 Apr; 7(4):181-2.
    View in: PubMed
  53. Sacher F, Wright M, Tedrow UB, O’Neill MD, Jais P, Hocini M, Macdonald R, Davies DW, Kanagaratnam P, Derval N, Epstein L, Peters NS, Stevenson WG, Haissaguerre M. Wolff-Parkinson-White ablation after a prior failure: a 7-year multicentre experience. Europace. 2010 Jun; 12(6):835-41.
    View in: PubMed
  54. Inada K, Roberts-Thomson KC, Seiler J, Steven D, Tedrow UB, Koplan BA, Stevenson WG. Mortality and safety of catheter ablation for antiarrhythmic drug-refractory ventricular tachycardia in elderly patients with coronary artery disease. Heart Rhythm. 2010 Jun; 7(6):740-4.
    View in: PubMed
  55. Steven D, Seiler J, Roberts-Thomson KC, Inada K, Stevenson WG. Mapping of atrial tachycardias after catheter ablation for atrial fibrillation: use of bi-atrial activation patterns to facilitate recognition of origin. Heart Rhythm. 2010 May; 7(5):664-72.
    View in: PubMed
  56. Stevenson WG, Tedrow U. Preventing ventricular tachycardia with catheter ablation. Lancet. 2010 Jan 2; 375(9708):4-6.
    View in: PubMed
  57. Al-Khatib SM, Calkins H, Eloff BC, Packer DL, Ellenbogen KA, Hammill SC, Natale A, Page RL, Prystowsky E, Jackman WM, Stevenson WG, Waldo AL, Wilber D, Kowey P, Yaross MS, Mark DB, Reiffel J, Finkle JK, Marinac-Dabic D, Pinnow E, Sager P, Sedrakyan A, Canos D, Gross T, Berliner E, Krucoff MW. Planning the Safety of Atrial Fibrillation Ablation Registry Initiative (SAFARI) as a Collaborative Pan-Stakeholder Critical Path Registry Model: a Cardiac Safety Research Consortium “Incubator” Think Tank. Am Heart J. 2010 Jan; 159(1):17-24.
    View in: PubMed
  58. Seiler J, Stevenson WG. Atrial fibrillation in congestive heart failure. Cardiol Rev. 2010 Jan-Feb; 18(1):38-50.
    View in: PubMed
  59. Steven D, Roberts-Thomson KC, Seiler J, Inada K, Tedrow UB, Mitchell RN, Sobieszczyk PS, Eisenhauer AC, Couper GS, Stevenson WG. Ventricular tachycardia arising from the aortomitral continuity in structural heart disease: characteristics and therapeutic considerations for an anatomically challenging area of origin. Circ Arrhythm Electrophysiol. 2009 Dec; 2(6):660-6.
    View in: PubMed
  60. Roberts-Thomson KC, Seiler J, Steven D, Inada K, Michaud GF, John RM, Koplan BA, Epstein LM, Stevenson WG, Tedrow UB. Percutaneous access of the epicardial space for mapping ventricular and supraventricular arrhythmias in patients with and without prior cardiac surgery. J Cardiovasc Electrophysiol. 2010 Apr; 21(4):406-11.
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  61. Steven D, Reddy VY, Inada K, Roberts-Thomson KC, Seiler J, Stevenson WG, Michaud GF. Loss of pace capture on the ablation line: a new marker for complete radiofrequency lesions to achieve pulmonary vein isolation. Heart Rhythm. 2010 Mar; 7(3):323-30.
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  62. Roberts-Thomson KC, Steven D, Seiler J, Inada K, Koplan BA, Tedrow UB, Epstein LM, Stevenson WG. Coronary artery injury due to catheter ablation in adults: presentations and outcomes. Circulation. 2009 Oct 13; 120(15):1465-73.
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  63. See VY, Roberts-Thomson KC, Stevenson WG, Camp PC, Koplan BA. Atrial arrhythmias after lung transplantation: epidemiology, mechanisms at electrophysiology study, and outcomes. Circ Arrhythm Electrophysiol. 2009 Oct; 2(5):504-10.
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  64. Stevenson WG, Saltzman JR. Gastroesophageal reflux and atrial-esophageal fistula. Heart Rhythm. 2009 Oct; 6(10):1463-4.
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  65. Aliot EM, Stevenson WG, Almendral-Garrote JM, Bogun F, Calkins CH, Delacretaz E, Della Bella P, Hindricks G, Jaïs P, Josephson ME, Kautzner J, Kay GN, Kuck KH, Lerman BB, Marchlinski F, Reddy V, Schalij MJ, Schilling R, Soejima K, Wilber D. EHRA/HRS Expert Consensus on Catheter Ablation of Ventricular Arrhythmias: developed in a partnership with the European Heart Rhythm Association (EHRA), a Registered Branch of the European Society of Cardiology (ESC), and the Heart Rhythm Society (HRS); in collaboration with the American College of Cardiology (ACC) and the American Heart Association (AHA). Heart Rhythm. 2009 Jun; 6(6):886-933.
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  66. Aliot EM, Stevenson WG, Almendral-Garrote JM, Bogun F, Calkins CH, Delacretaz E, Bella PD, Hindricks G, Jaïs P, Josephson ME, Kautzner J, Kay GN, Kuck KH, Lerman BB, Marchlinski F, Reddy V, Schalij MJ, Schilling R, Soejima K, Wilber D. EHRA/HRS Expert Consensus on Catheter Ablation of Ventricular Arrhythmias: developed in a partnership with the European Heart Rhythm Association (EHRA), a Registered Branch of the European Society of Cardiology (ESC), and the Heart Rhythm Society (HRS); in collaboration with the American College of Cardiology (ACC) and the American Heart Association (AHA). Europace. 2009 Jun; 11(6):771-817.
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  67. Raymond JM, Sacher F, Winslow R, Tedrow U, Stevenson WG. Catheter ablation for scar-related ventricular tachycardias. Curr Probl Cardiol. 2009 May; 34(5):225-70.
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  68. Lee JC, Steven D, Roberts-Thomson KC, Raymond JM, Stevenson WG, Tedrow UB. Atrial tachycardias adjacent to the phrenic nerve: recognition, potential problems, and solutions. Heart Rhythm. 2009 Aug; 6(8):1186-91.
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  69. Steven D, Roberts-Thomson KC, Seiler J, Michaud GF, John RM, Stevenson WG. Fibrillation in the superior vena cava mimicking atrial tachycardia. Circ Arrhythm Electrophysiol. 2009 Apr; 2(2):e4-7.
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  70. Roberts-Thomson KC, Seiler J, Steven D, Inada K, John R, Michaud G, Stevenson WG. Short AV response to atrial extrastimuli during narrow complex tachycardia: what is the mechanism? J Cardiovasc Electrophysiol. 2009 Aug; 20(8):946-8.
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  71. Koplan BA, Stevenson WG. Ventricular tachycardia and sudden cardiac death. Mayo Clin Proc. 2009 Mar; 84(3):289-97.
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  72. Khairy P, Stevenson WG. Catheter ablation in tetralogy of Fallot. Heart Rhythm. 2009 Jul; 6(7):1069-74.
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  73. Stevenson WG, Tedrow UB, Koplan BA. Management of ventricular tachycardia complicating cardiac surgery. Heart Rhythm. 2009 Aug; 6(8 Suppl):S66-9.
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  74. Lee JC, Epstein LM, Huffer LL, Stevenson WG, Koplan BA, Tedrow UB. ICD lead proarrhythmia cured by lead extraction. Heart Rhythm. 2009 May; 6(5):613-8.
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  75. Tedrow U, Stevenson WG. Strategies for epicardial mapping and ablation of ventricular tachycardia. J Cardiovasc Electrophysiol. 2009 Jun; 20(6):710-3.
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  76. Stevenson WG. Ventricular scars and ventricular tachycardia. Trans Am Clin Climatol Assoc. 2009; 120:403-12.
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  77. Stevenson WG, Wilber DJ, Natale A, Jackman WM, Marchlinski FE, Talbert T, Gonzalez MD, Worley SJ, Daoud EG, Hwang C, Schuger C, Bump TE, Jazayeri M, Tomassoni GF, Kopelman HA, Soejima K, Nakagawa H. Irrigated radiofrequency catheter ablation guided by electroanatomic mapping for recurrent ventricular tachycardia after myocardial infarction: the multicenter thermocool ventricular tachycardia ablation trial. Circulation. 2008 Dec 16; 118(25):2773-82.
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  78. Seiler J, Lee JC, Roberts-Thomson KC, Stevenson WG. Intracardiac echocardiography guided catheter ablation of incessant ventricular tachycardia from the posterior papillary muscle causing tachycardia–mediated cardiomyopathy. Heart Rhythm. 2009 Mar; 6(3):389-92.
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  79. Eckart RE, Field ME, Hruczkowski TW, Forman DE, Dorbala S, Di Carli MF, Albert CE, Maisel WH, Epstein LM, Stevenson WG. Association of electrocardiographic morphology of exercise-induced ventricular arrhythmia with mortality. Ann Intern Med. 2008 Oct 7; 149(7):451-60, W82.
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  80. Goldberger JJ, Cain ME, Hohnloser SH, Kadish AH, Knight BP, Lauer MS, Maron BJ, Page RL, Passman RS, Siscovick D, Stevenson WG, Zipes DP. American Heart Association/american College of Cardiology Foundation/heart Rhythm Society scientific statement on noninvasive risk stratification techniques for identifying patients at risk for sudden cardiac death: a scientific statement from the American Heart Association Council on Clinical Cardiology Committee on Electrocardiography and Arrhythmias and Council on Epidemiology and Prevention. Heart Rhythm. 2008 Oct; 5(10):e1-21.
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  81. Goldberger JJ, Cain ME, Hohnloser SH, Kadish AH, Knight BP, Lauer MS, Maron BJ, Page RL, Passman RS, Siscovick D, Siscovick D, Stevenson WG, Zipes DP. American Heart Association/American College of Cardiology Foundation/Heart Rhythm Society scientific statement on noninvasive risk stratification techniques for identifying patients at risk for sudden cardiac death: a scientific statement from the American Heart Association Council on Clinical Cardiology Committee on Electrocardiography and Arrhythmias and Council on Epidemiology and Prevention. Circulation. 2008 Sep 30; 118(14):1497-1518.
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  82. Goldberger JJ, Cain ME, Hohnloser SH, Kadish AH, Knight BP, Lauer MS, Maron BJ, Page RL, Passman RS, Siscovick D, Stevenson WG, Zipes DP. American Heart Association/American College of Cardiology Foundation/Heart Rhythm Society Scientific Statement on Noninvasive Risk Stratification Techniques for Identifying Patients at Risk for Sudden Cardiac Death. A scientific statement from the American Heart Association Council on Clinical Cardiology Committee on Electrocardiography and Arrhythmias and Council on Epidemiology and Prevention. J Am Coll Cardiol. 2008 Sep 30; 52(14):1179-99.
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  83. Seiler J, Roberts-Thomson KC, Raymond JM, Vest J, Delacretaz E, Stevenson WG. Steam pops during irrigated radiofrequency ablation: feasibility of impedance monitoring for prevention. Heart Rhythm. 2008 Oct; 5(10):1411-6.
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  84. Roy D, Talajic M, Nattel S, Wyse DG, Dorian P, Lee KL, Bourassa MG, Arnold JM, Buxton AE, Camm AJ, Connolly SJ, Dubuc M, Ducharme A, Guerra PG, Hohnloser SH, Lambert J, Le Heuzey JY, O’Hara G, Pedersen OD, Rouleau JL, Singh BN, Stevenson LW, Stevenson WG, Thibault B, Waldo AL. Rhythm control versus rate control for atrial fibrillation and heart failure. N Engl J Med. 2008 Jun 19; 358(25):2667-77.
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  85. Sacher F, Tedrow UB, Field ME, Raymond JM, Koplan BA, Epstein LM, Stevenson WG. Ventricular tachycardia ablation: evolution of patients and procedures over 8 years. Circ Arrhythm Electrophysiol. 2008 Aug; 1(3):153-61.
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  86. Vest JA, Seiler J, Stevenson WG. Clinical use of cooled radiofrequency ablation. J Cardiovasc Electrophysiol. 2008 Jul; 19(7):769-73.
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  87. Stevenson WG, Berul CI. Arrhythmia and Electrophysiology: the eagle can land. Circ Arrhythm Electrophysiol. 2008 Apr; 1(1):1.
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  88. Roberts-Thomson KC, Seiler J, Raymond JM, Stevenson WG. Exercise induced tachycardia with atrioventricular dissociation: what is the mechanism? Heart Rhythm. 2009 Mar; 6(3):426-8.
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  89. Zeppenfeld K, Stevenson WG. Ablation of ventricular tachycardia in patients with structural heart disease. Pacing Clin Electrophysiol. 2008 Mar; 31(3):358-74.
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  90. Cooper JM, Sapp JL, Robinson D, Epstein LM, Stevenson WG. A rewarming maneuver demonstrates the contribution of blood flow to electrode cooling during internally irrigated RF ablation. J Cardiovasc Electrophysiol. 2008 Apr; 19(4):409-14.
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  91. Zeppenfeld K, Schalij MJ, Bartelings MM, Tedrow UB, Koplan BA, Soejima K, Stevenson WG. Catheter ablation of ventricular tachycardia after repair of congenital heart disease: electroanatomic identification of the critical right ventricular isthmus. Circulation. 2007 Nov 13; 116(20):2241-52.
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  92. Eckart RE, Hruczkowski TW, Tedrow UB, Koplan BA, Epstein LM, Stevenson WG. Sustained ventricular tachycardia associated with corrective valve surgery. Circulation. 2007 Oct 30; 116(18):2005-11.
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  93. Sacher F, Sobieszczyk P, Tedrow U, Eisenhauer AC, Field ME, Selwyn A, Raymond JM, Koplan B, Epstein LM, Stevenson WG. Transcoronary ethanol ventricular tachycardia ablation in the modern electrophysiology era. Heart Rhythm. 2008 Jan; 5(1):62-8.
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  94. Sacher F, Vest J, Raymond JM, Stevenson WG. Incessant donor-to-recipient atrial tachycardia after bilateral lung transplantation. Heart Rhythm. 2008 Jan; 5(1):149-51.
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  95. Sacher F, Vest J, Raymond JM, Stevenson WG. Atrial pacing inducing narrow QRS tachycardia followed by wide complex tachycardia. J Cardiovasc Electrophysiol. 2007 Nov; 18(11):1213-5.
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  96. Stevenson WG, Soejima K. Catheter ablation for ventricular tachycardia. Circulation. 2007 May 29; 115(21):2750-60.
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  97. Koplan BA, Stevenson WG. Sudden arrhythmic death syndrome. Heart. 2007 May; 93(5):547-8.
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  98. Parkash R, Stevenson WG. Atrial fibrillation and clinical events in chronic heart failure. J Am Coll Cardiol. 2007 Jan 23; 49(3):376; author reply 376-7.
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  99. Sacher F, Jais P, Stephenson K, O’Neill MD, Hocini M, Clementy J, Stevenson WG, Haissaguerre M. Phrenic nerve injury after catheter ablation of atrial fibrillation. Indian Pacing Electrophysiol J. 2007; 7(1):1-6.
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  100. Tedrow UB, Stevenson WG, Wood MA, Shepard RK, Hall K, Pellegrini CP, Ellenbogen KA. Activation sequence modification during cardiac resynchronization by manipulation of left ventricular epicardial pacing stimulus strength. Pacing Clin Electrophysiol. 2007 Jan; 30(1):65-9.
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  101. Dzau VJ, Antman EM, Black HR, Hayes DL, Manson JE, Plutzky J, Popma JJ, Stevenson W. The cardiovascular disease continuum validated: clinical evidence of improved patient outcomes: part I: Pathophysiology and clinical trial evidence (risk factors through stable coronary artery disease). Circulation. 2006 Dec 19; 114(25):2850-70.
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  102. Dzau VJ, Antman EM, Black HR, Hayes DL, Manson JE, Plutzky J, Popma JJ, Stevenson W. The cardiovascular disease continuum validated: clinical evidence of improved patient outcomes: part II: Clinical trial evidence (acute coronary syndromes through renal disease) and future directions. Circulation. 2006 Dec 19; 114(25):2871-91.
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  103. Stevenson WG, Tedrow U. Management of atrial fibrillation in patients with heart failure. Heart Rhythm. 2007 Mar; 4(3 Suppl):S28-30.
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  104. Tedrow U, Stevenson WG. Substrate mapping and the aging atrium. Heart Rhythm. 2007 Feb; 4(2):145-6.
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  105. Eckart RE, Hruczkowski TW, Stevenson WG, Epstein LM. Myopotentials leading to ventricular fibrillation detection after advisory defibrillator generator replacement. Pacing Clin Electrophysiol. 2006 Nov; 29(11):1273-6.
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  106. Perloff JK, Middlekauf HR, Child JS, Stevenson WG, Miner PD, Goldberg GD. Usefulness of post-ventriculotomy signal averaged electrocardiograms in congenital heart disease. Am J Cardiol. 2006 Dec 15; 98(12):1646-51.
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  107. Koplan BA, Epstein LM, Albert CM, Stevenson WG. Survival in octogenarians receiving implantable defibrillators. Am Heart J. 2006 Oct; 152(4):714-9.
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  108. Veenhuyzen GD, Hruczkowski T, Dhir SK, Stevenson WG. Another way to prove the presence and participation of an accessory pathway in supraventricular tachycardia? J Cardiovasc Electrophysiol. 2006 Oct; 17(10):1147-9.
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  109. Yan AT, Shayne AJ, Brown KA, Gupta SN, Chan CW, Luu TM, Di Carli MF, Reynolds HG, Stevenson WG, Kwong RY. Characterization of the peri-infarct zone by contrast-enhanced cardiac magnetic resonance imaging is a powerful predictor of post-myocardial infarction mortality. Circulation. 2006 Jul 4; 114(1):32-9.
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  110. Sapp JL, Cooper JM, Zei P, Stevenson WG. Large radiofrequency ablation lesions can be created with a retractable infusion-needle catheter. J Cardiovasc Electrophysiol. 2006 Jun; 17(6):657-61.
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  111. Field ME, Miyazaki H, Epstein LM, Stevenson WG. Narrow complex tachycardia after slow pathway ablation: continue ablating? J Cardiovasc Electrophysiol. 2006 May; 17(5):557-9.
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  112. Tedrow UB, Kramer DB, Stevenson LW, Stevenson WG, Baughman KL, Epstein LM, Lewis EF. Relation of right ventricular peak systolic pressure to major adverse events in patients undergoing cardiac resynchronization therapy. Am J Cardiol. 2006 Jun 15; 97(12):1737-40.
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  113. Ames A, Stevenson WG. Cardiology patient page. Catheter ablation of atrial fibrillation. Circulation. 2006 Apr 4; 113(13):e666-8.
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  114. Koplan BA, Soejima K, Baughman K, Epstein LM, Stevenson WG. Refractory ventricular tachycardia secondary to cardiac sarcoid: electrophysiologic characteristics, mapping, and ablation. Heart Rhythm. 2006 Aug; 3(8):924-9.
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  115. Zei PC, Stevenson WG. Epicardial catheter mapping and ablation of ventricular tachycardia. Heart Rhythm. 2006 Mar; 3(3):360-3.
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  116. Miyazaki H, Stevenson WG, Stephenson K, Soejima K, Epstein LM. Entrainment mapping for rapid distinction of left and right atrial tachycardias. Heart Rhythm. 2006 May; 3(5):516-23.
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  117. Parkash R, Stevenson WG, Epstein LM, Maisel WH. Predicting early mortality after implantable defibrillator implantation: a clinical risk score for optimal patient selection. Am Heart J. 2006 Feb; 151(2):397-403.
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  118. Stevenson WG, Epstein LM. Endpoints for ablation of atrial fibrillation. Heart Rhythm. 2006 Feb; 3(2):146-7.
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  119. Stevenson LW, Stevenson WG. Cost-effectiveness of ICDs. N Engl J Med. 2006 Jan 12; 354(2):205-7; author reply 205-7.
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  120. Nazarian S, Maisel WH, Miles JS, Tsang S, Stevenson LW, Stevenson WG. Impact of implantable cardioverter defibrillators on survival and recurrent hospitalization in advanced heart failure. Am Heart J. 2005 Nov; 150(5):955-60.
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  121. Intini A, Goldstein RN, Jia P, Ramanathan C, Ryu K, Giannattasio B, Gilkeson R, Stambler BS, Brugada P, Stevenson WG, Rudy Y, Waldo AL. Electrocardiographic imaging (ECGI), a novel diagnostic modality used for mapping of focal left ventricular tachycardia in a young athlete. Heart Rhythm. 2005 Nov; 2(11):1250-2.
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  122. Parkash R, Maisel WH, Toca FM, Stevenson WG. Atrial fibrillation in heart failure: high mortality risk even if ventricular function is preserved. Am Heart J. 2005 Oct; 150(4):701-6.
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  123. Reynolds DW, Chen PS, Deal BJ, Donahue JK, Ellenbogen KA, Epstein AE, Friedman PA, Hammill SC, Hohnloser SH, Kanter RJ, Lindsay BD, Natale A, Saffitz J, Stevenson WG. Highlights of Heart Rhythm 2005, the Annual Scientific Sessions of the Heart Rhythm Society, May 4-7, 2005, New Orleans, Louisiana. Heart Rhythm. 2005 Sep; 2(9):1025-33.
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  124. Stevenson WG, Soejima K. Recording techniques for clinical electrophysiology. J Cardiovasc Electrophysiol. 2005 Sep; 16(9):1017-22.
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  125. Tedrow U, Stevenson WG, Benzaquen LR. Apical left ventricular aneurysm presenting with malignant ventricular tachycardia responsive to aneurysmectomy. Heart. 2005 May; 91(5):623.
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  126. Brunckhorst CB, Delacretaz E, Soejima K, Maisel WH, Friedman PL, Stevenson WG. Impact of changing activation sequence on bipolar electrogram amplitude for voltage mapping of left ventricular infarcts causing ventricular tachycardia. J Interv Card Electrophysiol. 2005 Mar; 12(2):137-41.
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  127. Stevenson WG. Catheter ablation of monomorphic ventricular tachycardia. Curr Opin Cardiol. 2005 Jan; 20(1):42-7.
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  128. Stevenson WG. To freeze or burn the epicardium? Heart Rhythm. 2005 Jan; 2(1):91-2.
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  129. Stevenson WG, Chaitman BR, Ellenbogen KA, Epstein AE, Gross WL, Hayes DL, Strickberger SA, Sweeney MO. Clinical assessment and management of patients with implanted cardioverter-defibrillators presenting to nonelectrophysiologists. Circulation. 2004 Dec 21; 110(25):3866-9.
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  130. Tedrow U, Maisel WH, Epstein LM, Soejima K, Stevenson WG. Feasibility of adjusting paced left ventricular activation by manipulating stimulus strength. J Am Coll Cardiol. 2004 Dec 7; 44(11):2249-52.
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  131. Stevenson WG, Stevenson LW. Atrial fibrillation and heart failure–five more years. N Engl J Med. 2004 Dec 2; 351(23):2437-40.
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  132. Brunckhorst CB, Delacretaz E, Soejima K, Jackman WM, Nakagawa H, Kuck KH, Ben-Haim SA, Seifert B, Stevenson WG. Ventricular mapping during atrial and right ventricular pacing: relation of electrogram parameters to ventricular tachycardia reentry circuits after myocardial infarction. J Interv Card Electrophysiol. 2004 Dec; 11(3):183-91.
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  133. Curtis AB, Abraham WT, Chen PS, Ellenbogen KA, Epstein AE, Friedman PA, Hohnloser SH, Kanter RJ, Stevenson WG. Highlights of Heart Rhythm 2004, the Annual Scientific Sessions of the Heart Rhythm Society: May 19 to 22, 2004, in San Francisco, California. J Am Coll Cardiol. 2004 Oct 19; 44(8):1550-6.
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  134. Stevenson WG, Cooper J, Sapp J. Optimizing RF output for cooled RF ablation. J Cardiovasc Electrophysiol. 2004 Oct; 15(10 Suppl):S24-7.
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  135. Soejima K, Stevenson WG. Athens, athletes, and arrhythmias: the cardiologist’s dilemma. J Am Coll Cardiol. 2004 Sep 1; 44(5):1059-61.
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  136. Cooper JM, Sapp JL, Tedrow U, Pellegrini CP, Robinson D, Epstein LM, Stevenson WG. Ablation with an internally irrigated radiofrequency catheter: learning how to avoid steam pops. Heart Rhythm. 2004 Sep; 1(3):329-33.
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  137. Soejima K, Couper G, Cooper JM, Sapp JL, Epstein LM, Stevenson WG. Subxiphoid surgical approach for epicardial catheter-based mapping and ablation in patients with prior cardiac surgery or difficult pericardial access. Circulation. 2004 Sep 7; 110(10):1197-201.
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  138. Brunckhorst CB, Delacretaz E, Soejima K, Maisel WH, Friedman PL, Stevenson WG. Identification of the ventricular tachycardia isthmus after infarction by pace mapping. Circulation. 2004 Aug 10; 110(6):652-9.
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  139. Friedman PL, Dubuc M, Green MS, Jackman WM, Keane DT, Marinchak RA, Nazari J, Packer DL, Skanes A, Steinberg JS, Stevenson WG, Tchou PJ, Wilber DJ, Worley SJ. Catheter cryoablation of supraventricular tachycardia: results of the multicenter prospective “frosty” trial. Heart Rhythm. 2004 Jul; 1(2):129-38.
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  140. Sapp JL, Soejima K, Cooper JM, Epstein LM, Stevenson WG. Ablation lesion size correlates with pacing threshold: a physiological basis for use of pacing to assess ablation lesions. Pacing Clin Electrophysiol. 2004 Jul; 27(7):933-7.
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  141. Soejima K, Stevenson WG, Sapp JL, Selwyn AP, Couper G, Epstein LM. Endocardial and epicardial radiofrequency ablation of ventricular tachycardia associated with dilated cardiomyopathy: the importance of low-voltage scars. J Am Coll Cardiol. 2004 May 19; 43(10):1834-42.
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  142. Tedrow U, Sweeney MO, Stevenson WG. Physiology of cardiac resynchronization. Curr Cardiol Rep. 2004 May; 6(3):189-93.
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  143. Sapp JL, Cooper JM, Soejima K, Sorrell T, Lopera G, Satti SD, Koplan BA, Epstein LM, Edelman E, Rogers C, Stevenson WG. Deep myocardial ablation lesions can be created with a retractable needle-tipped catheter. Pacing Clin Electrophysiol. 2004 May; 27(5):594-9.
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  144. Stevenson WG, Sweeney MO. Single site left ventricular pacing for cardiac resynchronization. Circulation. 2004 Apr 13; 109(14):1694-6.
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  145. Koplan BA, Parkash R, Couper G, Stevenson WG. Combined epicardial-endocardial approach to ablation of inappropriate sinus tachycardia. J Cardiovasc Electrophysiol. 2004 Feb; 15(2):237-40.
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  146. Lopera G, Stevenson WG, Soejima K, Maisel WH, Koplan B, Sapp JL, Satti SD, Epstein LM. Identification and ablation of three types of ventricular tachycardia involving the his-purkinje system in patients with heart disease. J Cardiovasc Electrophysiol. 2004 Jan; 15(1):52-8.
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  147. Blomström-Lundqvist C, Scheinman MM, Aliot EM, Alpert JS, Calkins H, Camm AJ, Campbell WB, Haines DE, Kuck KH, Lerman BB, Miller DD, Shaeffer CW, Stevenson WG, Tomaselli GF, Antman EM, Smith SC, Alpert JS, Faxon DP, Fuster V, Gibbons RJ, Gregoratos G, Hiratzka LF, Hunt SA, Jacobs AK, Russell RO, Priori SG, Blanc JJ, Budaj A, Burgos EF, Cowie M, Deckers JW, Garcia MA, Klein WW, Lekakis J, Lindahl B, Mazzotta G, Morais JC, Oto A, Smiseth O, Trappe HJ. ACC/AHA/ESC guidelines for the management of patients with supraventricular arrhythmias–executive summary. a report of the American college of cardiology/American heart association task force on practice guidelines and the European society of cardiology committee for practice guidelines (writing committee to develop guidelines for the management of patients with supraventricular arrhythmias) developed in collaboration with NASPE-Heart Rhythm Society. J Am Coll Cardiol. 2003 Oct 15; 42(8):1493-531.
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  148. Blomström-Lundqvist C, Scheinman MM, Aliot EM, Alpert JS, Calkins H, Camm AJ, Campbell WB, Haines DE, Kuck KH, Lerman BB, Miller DD, Shaeffer CW, Stevenson WG, Tomaselli GF, Antman EM, Smith SC, Alpert JS, Faxon DP, Fuster V, Gibbons RJ, Gregoratos G, Hiratzka LF, Hunt SA, Jacobs AK, Russell RO, Priori SG, Blanc JJ, Budaj A, Burgos EF, Cowie M, Deckers JW, Garcia MA, Klein WW, Lekakis J, Lindahl B, Mazzotta G, Morais JC, Oto A, Smiseth O, Trappe HJ. ACC/AHA/ESC guidelines for the management of patients with supraventricular arrhythmias–executive summary: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines and the European Society of Cardiology Committee for Practice Guidelines (Writing Committee to Develop Guidelines for the Management of Patients With Supraventricular Arrhythmias). Circulation. 2003 Oct 14; 108(15):1871-909.
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  149. Delacretaz E, Soejima K, Brunckhorst CB, Maisel WH, Friedman PL, Stevenson WG. Assessment of radiofrequency ablation effect from unipolar pacing threshold. Pacing Clin Electrophysiol. 2003 Oct; 26(10):1993-6.
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  150. Soejima K, Stevenson WG. Catheter ablation of ventricular tachycardia in patients with ischemic heart disease. Curr Cardiol Rep. 2003 Sep; 5(5):364-8.
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  151. Tung S, Soejima K, Maisel WH, Suzuki M, Epstein L, Stevenson WG. Recognition of far-field electrograms during entrainment mapping of ventricular tachycardia. J Am Coll Cardiol. 2003 Jul 2; 42(1):110-5.
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  152. Stevenson WG, Soejima K. Inside or out? Another option for incessant ventricular tachycardia. J Am Coll Cardiol. 2003 Jun 4; 41(11):2044-5.
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  153. Brunckhorst CB, Stevenson WG, Soejima K, Maisel WH, Delacretaz E, Friedman PL, Ben-Haim SA. Relationship of slow conduction detected by pace-mapping to ventricular tachycardia re-entry circuit sites after infarction. J Am Coll Cardiol. 2003 Mar 5; 41(5):802-9.
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  154. Koplan BA, Stevenson WG, Epstein LM, Aranki SF, Maisel WH. Development and validation of a simple risk score to predict the need for permanent pacing after cardiac valve surgery. J Am Coll Cardiol. 2003 Mar 5; 41(5):795-801.
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  155. Ellison KE, Stevenson WG, Sweeney MO, Epstein LM, Maisel WH. Management of arrhythmias in heart failure. Congest Heart Fail. 2003 Mar-Apr; 9(2):91-9.
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  156. Stevenson WG, Epstein LM. Predicting sudden death risk for heart failure patients in the implantable cardioverter-defibrillator age. Circulation. 2003 Feb 4; 107(4):514-6.
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  157. Maisel WH, Stevenson WG, Epstein LM. Changing trends in pacemaker and implantable cardioverter defibrillator generator advisories. Pacing Clin Electrophysiol. 2002 Dec; 25(12):1670-8.
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  158. Khan HH, Maisel WH, Ho C, Suzuki M, Soejima K, Solomon S, Stevenson WG. Effect of radiofrequency catheter ablation of ventricular tachycardia on left ventricular function in patients with prior myocardial infarction. J Interv Card Electrophysiol. 2002 Dec; 7(3):243-7.
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  159. Fenelon G, Stambler BS, Huvelle E, Brugada P, Stevenson WG. Left ventricular dysfunction is associated with prolonged average ventricular fibrillation cycle length in patients with implantable cardioverter defibrillators. J Interv Card Electrophysiol. 2002 Dec; 7(3):249-54.
    View in: PubMed
  160. Soejima K, Stevenson WG, Maisel WH, Sapp JL, Epstein LM. Electrically unexcitable scar mapping based on pacing threshold for identification of the reentry circuit isthmus: feasibility for guiding ventricular tachycardia ablation. Circulation. 2002 Sep 24; 106(13):1678-83.
    View in: PubMed
  161. Maisel WH, Stevenson WG. Syncope–getting to the heart of the matter. N Engl J Med. 2002 Sep 19; 347(12):931-3.
    View in: PubMed
  162. Maisel WH, Stevenson WG, Epstein LM. Reduced atrial blood flow in patients with coronary artery disease. Coron Artery Dis. 2002 Aug; 13(5):283-90.
    View in: PubMed
  163. Soejima K, Stevenson WG. Ventricular tachycardia associated with myocardial infarct scar: a spectrum of therapies for a single patient. Circulation. 2002 Jul 9; 106(2):176-9.
    View in: PubMed
  164. Brunckhorst CB, Stevenson WG, Jackman WM, Kuck KH, Soejima K, Nakagawa H, Cappato R, Ben-Haim SA. Ventricular mapping during atrial and ventricular pacing. Relationship of multipotential electrograms to ventricular tachycardia reentry circuits after myocardial infarction. Eur Heart J. 2002 Jul; 23(14):1131-8.
    View in: PubMed
  165. Friedman RA, Walsh EP, Silka MJ, Calkins H, Stevenson WG, Rhodes LA, Deal BJ, Wolff GS, Demaso DR, Hanisch D, Van Hare GF. NASPE Expert Consensus Conference: Radiofrequency catheter ablation in children with and without congenital heart disease. Report of the writing committee. North American Society of Pacing and Electrophysiology. Pacing Clin Electrophysiol. 2002 Jun; 25(6):1000-17.
    View in: PubMed
  166. Stevenson WG, Ellison KE, Sweeney MO, Epstein LM, Maisel WH. Management of arrhythmias in heart failure. Cardiol Rev. 2002 Jan-Feb; 10(1):8-14.
    View in: PubMed
  167. Maisel WH, Rawn JD, Stevenson WG. Atrial fibrillation after cardiac surgery. Ann Intern Med. 2001 Dec 18; 135(12):1061-73.
    View in: PubMed
  168. Sapp J, Soejima K, Couper GS, Stevenson WG. Electrophysiology and anatomic characterization of an epicardial accessory pathway. J Cardiovasc Electrophysiol. 2001 Dec; 12(12):1411-4.
    View in: PubMed
  169. Sweeney MO, Ellison KE, Stevenson WG. Implantable cardioverter defibrillators in heart failure. Cardiol Clin. 2001 Nov; 19(4):653-67.
    View in: PubMed
  170. Maisel WH, Stevenson WG, Tung S, Blier LE, Brunckhorst CB. Less is more: 4:2:1 block. Circulation. 2001 Sep 4; 104(10):E50.
    View in: PubMed
  171. Delacrétaz E, Stevenson WG. Catheter ablation of ventricular tachycardia in patients with coronary heart disease. Part II: Clinical aspects, limitations, and recent developments. Pacing Clin Electrophysiol. 2001 Sep; 24(9 Pt 1):1403-11.
    View in: PubMed
  172. Maisel WH, Sweeney MO, Stevenson WG, Ellison KE, Epstein LM. Recalls and safety alerts involving pacemakers and implantable cardioverter-defibrillator generators. JAMA. 2001 Aug 15; 286(7):793-9.
    View in: PubMed
  173. Soejima K, Suzuki M, Maisel WH, Brunckhorst CB, Delacretaz E, Blier L, Tung S, Khan H, Stevenson WG. Catheter ablation in patients with multiple and unstable ventricular tachycardias after myocardial infarction: short ablation lines guided by reentry circuit isthmuses and sinus rhythm mapping. Circulation. 2001 Aug 7; 104(6):664-9.
    View in: PubMed
  174. Delacretaz E, Stevenson WG. Catheter ablation of ventricular tachycardia in patients with coronary heart disease: part I: Mapping. Pacing Clin Electrophysiol. 2001 Aug; 24(8 Pt 1):1261-77.
    View in: PubMed
  175. Delacretaz E, Ganz LI, Soejima K, Friedman PL, Walsh EP, Triedman JK, Sloss LJ, Landzberg MJ, Stevenson WG. Multi atrial maco-re-entry circuits in adults with repaired congenital heart disease: entrainment mapping combined with three-dimensional electroanatomic mapping. J Am Coll Cardiol. 2001 May; 37(6):1665-76.
    View in: PubMed
  176. Soejima K, Delacretaz E, Suzuki M, Brunckhorst CB, Maisel WH, Friedman PL, Stevenson WG. Saline-cooled versus standard radiofrequency catheter ablation for infarct-related ventricular tachycardias. Circulation. 2001 Apr 10; 103(14):1858-62.
    View in: PubMed
  177. Soejima K, Stevenson WG, Maisel WH, Delacretaz E, Brunckhorst CB, Ellison KE, Friedman PL. The N + 1 difference: a new measure for entrainment mapping. J Am Coll Cardiol. 2001 Apr; 37(5):1386-94.
    View in: PubMed
  178. Delacretaz E, Soejima K, Gottipaty VK, Brunckhorst CB, Friedman PL, Stevenson WG. Single catheter determination of local electrogram prematurity using simultaneous unipolar and bipolar recordings to replace the surface ECG as a timing reference. Pacing Clin Electrophysiol. 2001 Apr; 24(4 Pt 1):441-9.
    View in: PubMed
  179. Stevenson WG, Maisel WH. Electrocardiography artifact: what you do not know, you do not recognize. Am J Med. 2001 Apr 1; 110(5):402-3.
    View in: PubMed
  180. Stevenson WG, Soejima K. Knowing where to look. J Cardiovasc Electrophysiol. 2001 Mar; 12(3):367-8.
    View in: PubMed
  181. Stevenson WG, Stevenson LW. Prevention of sudden death in heart failure. J Cardiovasc Electrophysiol. 2001 Jan; 12(1):112-4.
    View in: PubMed
  182. Stevenson WG, Delacretaz E. Radiofrequency catheter ablation of ventricular tachycardia. Heart. 2000 Nov; 84(5):553-9.
    View in: PubMed
  183. Stevenson WG, Delacretaz E. Strategies for catheter ablation of scar-related ventricular tachycardia. Curr Cardiol Rep. 2000 Nov; 2(6):537-44.
    View in: PubMed
  184. Soejima K, Stevenson WG, Delacretaz E, Brunckhorst CB, Maisel WH, Friedman PL. Identification of left atrial origin of ectopic tachycardia during right atrial mapping: analysis of double potentials at the posteromedial right atrium. J Cardiovasc Electrophysiol. 2000 Sep; 11(9):975-80.
    View in: PubMed
  185. Weinfeld MS, Drazner MH, Stevenson WG, Stevenson LW. Early outcome of initiating amiodarone for atrial fibrillation in advanced heart failure. J Heart Lung Transplant. 2000 Jul; 19(7):638-43.
    View in: PubMed
  186. Maisel WH, Stevenson WG. Sudden death and the electrophysiological effects of angiotensin-converting enzyme inhibitors. J Card Fail. 2000 Jun; 6(2):80-2.
    View in: PubMed
  187. Ellison KE, Stevenson WG, Sweeney MO, Lefroy DC, Delacretaz E, Friedman PL. Catheter ablation for hemodynamically unstable monomorphic ventricular tachycardia. J Cardiovasc Electrophysiol. 2000 Jan; 11(1):41-4.
    View in: PubMed
  188. Delacretaz E, Stevenson WG, Ellison KE, Maisel WH, Friedman PL. Mapping and radiofrequency catheter ablation of the three types of sustained monomorphic ventricular tachycardia in nonischemic heart disease. J Cardiovasc Electrophysiol. 2000 Jan; 11(1):11-7.
    View in: PubMed
  189. Delacretaz E, Soejima K, Stevenson WG, Friedman PL. Short ventriculoatrial intervals during orthodromic atrioventricular reciprocating tachycardia: what is the mechanism? J Cardiovasc Electrophysiol. 2000 Jan; 11(1):121-4.
    View in: PubMed
  190. Soejima K, Delacretaz E, Stevenson WG, Friedman PL. DDD-pacing-induced cardiomyopathy following AV node ablation for persistent atrial tachycardia. J Interv Card Electrophysiol. 1999 Dec; 3(4):321-3.
    View in: PubMed
  191. Stevenson WG, Stevenson LW. Atrial fibrillation in heart failure. N Engl J Med. 1999 Sep 16; 341(12):910-1.
    View in: PubMed
  192. Kocovic DZ, Harada T, Friedman PL, Stevenson WG. Characteristics of electrograms recorded at reentry circuit sites and bystanders during ventricular tachycardia after myocardial infarction. J Am Coll Cardiol. 1999 Aug; 34(2):381-8.
    View in: PubMed
  193. Delacretaz E, Stevenson WG, Winters GL, Mitchell RN, Stewart S, Lynch K, Friedman PL. Ablation of ventricular tachycardia with a saline-cooled radiofrequency catheter: anatomic and histologic characteristics of the lesions in humans. J Cardiovasc Electrophysiol. 1999 Jun; 10(6):860-5.
    View in: PubMed
  194. Delacretaz E, Stevenson WG, Winters GL, Friedman PL. Radiofrequency ablation of atrial flutter. Circulation. 1999 Apr 13; 99(14):E1-2.
    View in: PubMed
  195. Friedman PL, Stevenson WG. Proarrhythmia. Am J Cardiol. 1998 Oct 16; 82(8A):50N-58N.
    View in: PubMed
  196. Ellison KE, Friedman PL, Ganz LI, Stevenson WG. Entrainment mapping and radiofrequency catheter ablation of ventricular tachycardia in right ventricular dysplasia. J Am Coll Cardiol. 1998 Sep; 32(3):724-8.
    View in: PubMed
  197. Lefroy DC, Fang JC, Stevenson LW, Hartley LH, Friedman PL, Stevenson WG. Recipient-to-donor atrioatrial conduction after orthotopic heart transplantation: surface electrocardiographic features and estimated prevalence. Am J Cardiol. 1998 Aug 15; 82(4):444-50.
    View in: PubMed
  198. Stevenson WG, Friedman PL, Kocovic D, Sager PT, Saxon LA, Pavri B. Radiofrequency catheter ablation of ventricular tachycardia after myocardial infarction. Circulation. 1998 Jul 28; 98(4):308-14.
    View in: PubMed
  199. Stevenson WG, Delacretaz E, Friedman PL, Ellison KE. Identification and ablation of macroreentrant ventricular tachycardia with the CARTO electroanatomical mapping system. Pacing Clin Electrophysiol. 1998 Jul; 21(7):1448-56.
    View in: PubMed
  200. Lefroy DC, Ellison KE, Friedman PL, Stevenson WG. Arrhythmia of the month: shortening of ventriculoatrial conduction time during radiofrequency catheter ablation of a concealed accessory pathway. J Cardiovasc Electrophysiol. 1998 Apr; 9(4):445-7.
    View in: PubMed
  201. Ganz LI, Couper GS, Friedman PL, Stevenson WG, Ellison K. Use of telemetered permanent pacemaker intracardiac electrograms to diagnose ventricular tachycardia. Am J Cardiol. 1997 Dec 1; 80(11):1511-3.
    View in: PubMed
  202. stevenson WG, Friedman PL, Ganz LI. Radiofrequency catheter ablation of ventricular tachycardia late after myocardial infarction. J Cardiovasc Electrophysiol. 1997 Nov; 8(11):1309-19.
    View in: PubMed
  203. Stevenson WG, Ellison KE, Lefroy DC, Friedman PL. Ablation therapy for cardiac arrhythmias. Am J Cardiol. 1997 Oct 23; 80(8A):56G-66G.
    View in: PubMed
  204. Ellison KE, Stevenson WG, Couper GS, Friedman PL. Ablation of ventricular tachycardia due to a postinfarct ventricular septal defect: identification and transection of a broad reentry loop. J Cardiovasc Electrophysiol. 1997 Oct; 8(10):1163-6.
    View in: PubMed
  205. Harada T, Stevenson WG, Kocovic DZ, Friedman PL. Catheter ablation of ventricular tachycardia after myocardial infarction: relation of endocardial sinus rhythm late potentials to the reentry circuit. J Am Coll Cardiol. 1997 Oct; 30(4):1015-23.
    View in: PubMed
  206. Stevenson WG, Sweeney MO. Arrhythmias and sudden death in heart failure. Jpn Circ J. 1997 Sep; 61(9):727-40.
    View in: PubMed
  207. Maisel WH, Kuntz KM, Reimold SC, Lee TH, Antman EM, Friedman PL, Stevenson WG. Risk of initiating antiarrhythmic drug therapy for atrial fibrillation in patients admitted to a university hospital. Ann Intern Med. 1997 Aug 15; 127(4):281-4.
    View in: PubMed
  208. Stevenson WG, Sweeney MO. Pharmacologic and nonpharmacologic treatment of ventricular arrhythmias in heart failure. Curr Opin Cardiol. 1997 May; 12(3):242-50.
    View in: PubMed
  209. Stevenson WG, Friedman PL, Sager PT, Saxon LA, Kocovic D, Harada T, Wiener I, Khan H. Exploring postinfarction reentrant ventricular tachycardia with entrainment mapping. J Am Coll Cardiol. 1997 May; 29(6):1180-9.
    View in: PubMed
  210. Hadjis TA, Stevenson WG, Harada T, Friedman PL, Sager P, Saxon LA. Preferential locations for critical reentry circuit sites causing ventricular tachycardia after inferior wall myocardial infarction. J Cardiovasc Electrophysiol. 1997 Apr; 8(4):363-70.
    View in: PubMed
  211. Hadjis TA, Harada T, Stevenson WG, Friedman PL. Effect of recording site on postpacing interval measurement during catheter mapping and entrainment of postinfarction ventricular tachycardia. J Cardiovasc Electrophysiol. 1997 Apr; 8(4):398-404.
    View in: PubMed
  212. Merliss AD, Seifert MJ, Collins RF, Higgins JP, Reimold SC, Lee RT, Friedman PL, Stevenson WG. Catheter ablation of idiopathic left ventricular tachycardia associated with a false tendon. Pacing Clin Electrophysiol. 1996 Dec; 19(12 Pt 1):2144-6.
    View in: PubMed
  213. Stevenson WG, Stevenson LW, Middlekauff HR, Fonarow GC, Hamilton MA, Woo MA, Saxon LA, Natterson PD, Steimle A, Walden JA, Tillisch JH. Improving survival for patients with atrial fibrillation and advanced heart failure. J Am Coll Cardiol. 1996 Nov 15; 28(6):1458-63.
    View in: PubMed
  214. Stevenson WG, Ridker PM. Should survivors of myocardial infarction with low ejection fraction be routinely referred to arrhythmia specialists? JAMA. 1996 Aug 14; 276(6):481-5.
    View in: PubMed
  215. Friedman PL, Stevenson WG, Kocovic DZ. Autonomic dysfunction after catheter ablation. J Cardiovasc Electrophysiol. 1996 May; 7(5):450-9.
    View in: PubMed
  216. Ganz LI, Stevenson WG. Catheter mapping and ablation of ventricular tachycardia. Coron Artery Dis. 1996 Jan; 7(1):29-35.
    View in: PubMed
  217. Stevenson WG, Stevenson LW, Middlekauff HR, Fonarow GC, Hamilton MA, Woo MA, Saxon LA, Natterson PD, Steimle A, Walden JA, et al. Improving survival for patients with advanced heart failure: a study of 737 consecutive patients. J Am Coll Cardiol. 1995 Nov 15; 26(6):1417-23.
    View in: PubMed
  218. Stevenson WG. Ventricular tachycardia after myocardial infarction: from arrhythmia surgery to catheter ablation. J Cardiovasc Electrophysiol. 1995 Oct; 6(10 Pt 2):942-50.
    View in: PubMed
  219. Bartlett TG, Mitchell R, Friedman PL, Stevenson WG. Histologic evolution of radiofrequency lesions in an old human myocardial infarct causing ventricular tachycardia. J Cardiovasc Electrophysiol. 1995 Aug; 6(8):625-9.
    View in: PubMed
  220. Stevenson WG, Sager PT, Natterson PD, Saxon LA, Middlekauff HR, Wiener I. Relation of pace mapping QRS configuration and conduction delay to ventricular tachycardia reentry circuits in human infarct scars. J Am Coll Cardiol. 1995 Aug; 26(2):481-8.
    View in: PubMed
  221. Stevenson WG. Mechanisms and management of arrhythmias in heart failure. Curr Opin Cardiol. 1995 May; 10(3):274-81.
    View in: PubMed
  222. Stevenson WG, Sager PT, Friedman PL. Entrainment techniques for mapping atrial and ventricular tachycardias. J Cardiovasc Electrophysiol. 1995 Mar; 6(3):201-16.
    View in: PubMed
  223. Stevenson WG. Functional approach to site-by-site catheter mapping of ventricular reentry circuits in chronic infarctions. J Electrocardiol. 1994; 27 Suppl:130-8.
    View in: PubMed

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Summary of Genomics and Medicine: Role in Cardiovascular Diseases

Posted in Atherogenic Processes & Pathology, Best evidence, Biological Networks, Gene Regulation and Evolution, Biomarkers & Medical Diagnostics, Ca2+ triggered activation, Calcium Signaling, Calmodulin Kinase and Contraction, Cardiac & Vascular Repair Tools Subsegment, Cardiomyopathy, Cardiovascular Pharmacogenomics, Cardiovascular Research, Cell Biology, Signaling & Cell Circuits, Coagulation Therapy and Internal Bleeding, Computational Biology/Systems and Bioinformatics, Congenital Heart Disease, Curation, Cytoskeleton, Diabetes Mellitus, Disease Biology, Small Molecules in Development of Therapeutic Drugs, Experimental validation, Explanatory, Frontiers in Cardiology and Cardiovascular Disorders, Genome Biology, Genomic Testing: Methodology for Diagnosis, HTN, Human Immune System in Health and in Disease, Immunodiagnostics, International Global Work in Pharmaceutical, Medical and Population Genetics, Medical Devices R&D and Inventions, Medical Imaging Technology, Image Processing/Computing, MRI, CT, Nuclear Medicine, Ultra Sound, Metabolomics, Molecular Genetics & Pharmaceutical, Myocardial metabolism, Myocardial ischemia, myocardial perfusion, Myocardial adenine nucleotide metabolism, Nitric Oxide in Health and Disease, Nutrigenomics, Nutrition, Nutritional Supplements: Atherogenesis, lipid metabolism, Origins of Cardiovascular Disease, Personalized and Precision Medicine & Genomic Research, Pharmaceutical Analytics, Pharmacogenomics, Pharmacologic toxicities, Pharmacotherapy of Cardiovascular Disease, Population Health Management, Genetics & Pharmaceutical, Population Health Management, Nutrition and Phytochemistry, Pre-Clinical Animal Model Development, Proteomics, Technology Advance Assessment of, Technology Transfer: Biotech and Pharmaceutical, Translational Effectiveness, Translational Research, Translational Science, tagged , , , , , , , , , , , , , , , , , , , , , , , , , , on January 6, 2014| Leave a Comment »

Summary of Genomics and Medicine: Role in Cardiovascular Diseases

Author: Larry H. Bernstein, MD, FCAP

The articles within Chapters and Subchapters you have just read have been organized into four interconnected parts.
  1. Genomics and Medicine
  2. Epigenetics – Modifyable Factors Causing CVD
  3. Determinants of CVD – Genetics, Heredity and Genomics Discoveries
  4. Individualized Medicine Guided by Genetics and Genomics Discoveries
The first part established the
  • rapidly evolving science of genomics
  • aided by analytical and computational tools for the identification of nucleotide substitutions, or combinations of them
that have a significant association with the development of
  • cardiovascular diseases,
  • hypercoagulable state,
  • atherosclerosis,
  • microvascular disease,
  • endothelial disruption, and
  • type-2DM, to name a few.
These may well be associated with increased risk for stroke and/or peripheral vascular disease in some cases,
  • essentially because the involvement of the circulation is systemic in nature.

Part 1

establishes an important connection between RNA and disease expression.  This development has led to
  • the necessity of a patient-centric approach to patient-care.
When I entered medical school, it was eight years after Watson and Crick proposed the double helix.  It was also
  • the height of a series of discoveries elucidating key metabolic pathways.
In the period since then there have been treatments for some of the important well established metabolic diseases of
  • carbohydrate,
  • protein, and
  • lipid metabolism,
such as –  glycogen storage disease, and some are immense challenges, such as
  • Tay Sachs, or
  • Transthyretin-Associated amyloidosis.
But we have crossed a line delineating classical Mendelian genetics to
  • multifactorial non-linear traits of great complexity and
involving combinatorial program analyses to resolve.
The Human Genome Project was completed in 2001, and it has opened the floodgates of genomic discovery.  This resulted in the identification of
genomic alterations in
  • cardiovascular disease,
  • cancer,
  • microbial,
  • plant,
  • prion, and
  • metabolic diseases.
This has also led to
  • the identification of genomic targets
  • that are either involved in transcription or
  • are involved with cellular control mechanisms for targeted pharmaceutical development.
In addition, there is great pressure on the science of laboratory analytics to
  • codevelop with new drugs,
  • biomarkers that are indicators of toxicity or
  • of drug effectiveness.
I have not mentioned the dark matter of the genome. It has been substantially reduced, and has been termed dark because
  • this portion of the genome is not identified in transcription of proteins.
However, it has become a lightning rod to ongoing genomic investigation because of
  • an essential role in the regulation of nuclear and cytoplasmic activities.
Changes in the three dimensional structure of these genes due to
  • changes in Van der Waal forces and internucleotide distances lead to
  • conformational changes that could have an effect on cell activity.

Part 2

is an exploration of epigenetics in cardiovascular diseases.  Epigenetics is
  • the post-genomic modification of genetic expression
  • by the substitution of nucleotides or by the attachment of carbohydrate residues, or
  • by alterations in the hydrophobic forces between sequences that weaken or strengthen their expression.
This could operate in a manner similar to the conformational changes just described.  These changes
  • may be modifiable, and they
  • may be highly influenced by environmental factors, such as
    1. smoking and environmental toxins,
    2. diet,
    3. physical activity, and
    4. neutraceuticals.
While neutraceuticals is a black box industry that evolved from
  • the extraction of ancient herbal remedies of agricultural derivation
    (which could be extended to digitalis and Foxglove; or to coumadin; and to penecillin, and to other drugs that are not neutraceuticals).

The best examples are the importance of

  • n-3 fatty acids, and
  • fiber
  • dietary sulfur (in the source of methionine), folic acid, vitamin B12
  • arginine combined with citrulline to drive eNOS
  • and of iodine, which can’t be understated.
In addition, meat consumption involves the intake of fat that contains

  • the proinflammatory n-6 fatty acid.

The importance of the ratio of n-3/n-6 fatty acids in diet is not seriously discussed when

  • we look at the association of fat intake and disease etiology.
Part 2 then leads into signaling pathways and proteomics. The signaling pathways are
  • critical to understanding the inflammatory process, just as
  • dietary factors tie in with a balance that is maintained by dietary intake,
    • possibly gut bacteria utilization of delivered substrate, and
    • proinflammatory factors in disaease.
These are being explored by microfluidic proteomic and metabolomic technologies that were inconceivable a half century ago.
This portion extended into the diagnosis of cardiovascular disease, and
  • elucidated the relationship between platelet-endothelial interaction in the formation of vascular plaque.
It explored protein, proteomic, and genomic markers
  1. for identifying and classifying types of disease pathobiology, and
  2. for following treatment measures.

Part 3

connected with genetics and genomic discoveries in cardiovascular diseases.

Part 4

is the tie between life style habits and disease etiology, going forward with
  • the pursuit of cardiovascular disease prevention.
The presentation of walking and running, and of bariatric surgery (type 2DM) are fine examples.
It further discussed gene therapy and congenital heart disease.  But the most interesting presentations are
  • in the pharmacogenomics for cardiovascular diseases, with
    1. volyage-gated calcium-channels, and
    2. ApoE in the statin response.

This volume is a splendid example representative of the entire collection on cardiovascular diseases.

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Introduction to Genomics and Epigenomics Roles in Cardiovascular Diseases

Posted in Atherogenic Processes & Pathology, Best evidence, Cardiomyopathy, Cardiovascular Pharmacogenomics, Cardiovascular Research, Coagulation Therapy and Internal Bleeding, Congenital Heart Disease, Cytoskeleton, Diabetes Mellitus, Diagnostic Immunology, Disease Biology, Small Molecules in Development of Therapeutic Drugs, Evidence-based decision-making, Experimental validation, Frontiers in Cardiology and Cardiovascular Disorders, Genome Biology, HTN, Human Immune System in Health and in Disease, Immunodiagnostics, Innovation in Immunology Diagnostics, International Global Work in Pharmaceutical, Medical and Population Genetics, Metabolomics, Molecular Genetics & Pharmaceutical, Myocardial metabolism, Myocardial ischemia, myocardial perfusion, Myocardial adenine nucleotide metabolism, Nitric Oxide in Health and Disease, Nutrition, Nutritional Supplements: Atherogenesis, lipid metabolism, Origins of Cardiovascular Disease, Personalized and Precision Medicine & Genomic Research, Pharmaceutical Analytics, Pharmacogenomics, Pharmacologic toxicities, Pharmacotherapy of Cardiovascular Disease, Population Health Management, Genetics & Pharmaceutical, Population Health Management, Nutrition and Phytochemistry, Pre-Clinical Animal Model Development, Proteomics, Regulated Clinical Trials: Design, Methods, Components and IRB related issues, Statistical Methods for Research Evaluation, Systemic Inflammatory Response Related Disorders, Technology Advance Assessment of, Technology Transfer: Biotech and Pharmaceutical, Theoretic convergence, Translational Effectiveness, Translational Research, Translational Science, tagged , , , , , , , , , , , , , , , , , , , , , , , , , on January 5, 2014| Leave a Comment »

Introduction to Genomics and Epigenomics Roles in Cardiovascular Diseases

Author and Curator: Larry H Bernstein, MD, FCAP

This introduction is to a thorough evaluation of a rich source of research literature on the genomic influences, which may have variable strength in the biological causation of atherosclerosis, microvascular disease, plaque formation, not necessarily having expressing, except in a multivariable context that includes the environment, dietary factors, level of emotional stress, sleep habits, and the daily activities of living for affected individuals.  The potential of genomics is carried in the DNA, copied to RNA, and this is most well studied in the micro RNAs (miRNA).  The miRNA has been explored for the appearance in the circulation of specific miRNAs that might be associated with myocyte or endothelial cell injury, and they are also being used as targets for therapeutics by the creation of silencing RNAs (siRNA).  The extent to which there is evidence of success in these studies is limited, but is being translated from animal studies to human disease.  There is also a long history of the measurement of  circulating enzymes and isoenzymes (alanine amino transferase, creatine kinase, and lactate dehydrogenase, not to leave out the adenylate kinase species specific to myocardium), and more recently the release of troponins I and T, and the so far still not fully explored ischemia modified albumin, or of miRNAs for the diagnosis of myocardial infarction.

There is also a significant disagreement about the value of measuring high sensitivity C reactive protein (hs-CRP), which has always been a marker for systemic inflammatory disease, in both chronic rheumatic and infectious diseases having a broad range, so that procalcitonin has appeared to be better for that situation, and for early diagnosis of sepsis. The hs-CRP has been too easily ignored because of

1. the ubiquitous elevations in the population
2. the expressed concerns that one might not be inclined to treat a mild elevation without other risk factors, such as, LDL cholesterolemia, low HDL, absent diabetes or obesity.  Nevertheless, hs-CRP raises an reasonable argument for preventive measures, and perhaps the use of a statin.

There has been a substantial amount of work on the relationship of obesity to both type 2 diabetes mellitus (T2DM) and to coronary vascular disease and stroke.  Here we bring in the relationship of the vascular endothelium, adipose tissue secretion of adiponectin, and platelet activation.  A whole generation of antiplatelet drugs addresses the mechanism of platelet activation, adhession, and interaction with endothelium.   Very interesting work has appeared on RESISTIN, that could bear some fruit in the treatment of both obesity and T2DM.

It is important to keep in mind that epigenomic gene rearrangements or substitutions occur throughout life, and they may have an expression late in life.  Some of the known epigenetic events occur with some frequency, but the associations are extremely difficult to pin down, as well as the strength of the association.  In a population that is not diverse, epigenetic changes are passed on in the population in the period of childbearing age.  The establishment of an epigenetic change is diluted in a diverse population.  There have been a number of studies with different findings of association between cardiovascular disease and genetic mutations in the Han and also in the Uyger Chinese populations, which are distinctly different populations that is not part of this discussion.

This should be sufficient to elicit broad appeal in reading this volume on cardiovascular diseases, and perhaps the entire series.  Below is a diagram of this volume in the series.

PART 1 – Genomics and Medicine
Introduction to Genomics and Medicine (Vol 3)
Genomics and Medicine: The Physician’s View
Ribozymes and RNA Machines
Genomics and Medicine: Genomics to CVD Diagnoses
Establishing a Patient-Centric View of Genomic Data
VIDEO:  Implementing Biomarker Programs ­ P Ridker PART 2 – Epigenetics – Modifiable
Factors Causing CVD
Diseases Etiology
   Environmental Contributors
Implicated as Causing CVD
   Diet: Solids and Fluid Intake
and Nutraceuticals
   Physical Activity and
Prevention of CVD
   Psychological Stress and
Mental Health: Risk for CVD
   Correlation between
Cancer and CVD
PART 3  Determinants of CVD – Genetics, Heredity and Genomics Discoveries
Introduction
    Why cancer cells contain abnormal numbers of chromosomes (Aneuploidy)
     Functional Characterization of CV Genomics: Disease Case Studies @ 2013 ASHG
     Leading DIAGNOSES of CVD covered in Circulation: CV Genetics, 3/2010 – 3/2013
     Commentary on Biomarkers for Genetics and Genomics of CVD
PART 4 Individualized Medicine Guided by Genetics and Genomics Discoveries
    Preventive Medicine: Cardiovascular Diseases
    Walking and Running: Similar Risk Reductions for Hypertension, Hypercholesterolemia,
DM, and possibly CAD
http://pharmaceuticalintelligence.com/2013/04/04/walking-and-running-similar-risk-reductions-for-hypertension-hypercholesterolemia-dm-and-possibly-cad/
    Prevention of Type 2 Diabetes: Is Bariatric Surgery the Solution?
http://pharmaceuticalintelligence.com/2012/08/23/prevention-of-type-2-diabetes-is-bariatric-surgery-the-solution/
Gene-Therapy for CVD
Congenital Heart Disease/Defects
   Medical Etiologies: EBM – LEADING DIAGNOSES, Risks Pharmacogenomics for Cardio-
vascular Diseases
   Signaling Pathways     Response to Rosuvastatin in
Patients With Acute Myocardial Infarction:
Hepatic Metabolism and Transporter Gene
Variants Effect
http://pharmaceuticalintelligence.com/2014/
01/02/response-to-rosuvastatin-in-patients-
with-acute-myocardial-infarction-hepatic-
metabolism-and-transporter-gene-variants-effect/
   Proteomics and Metabolomics      Voltage-Gated Calcium Channel and Pharmaco-
genetic Association with Adverse Cardiovascular
Outcomes: Hypertension Treatment with Verapamil
SR (CCB) vs Atenolol (BB) or Trandolapril (ACE)
http://pharmaceuticalintelligence.com/2014/01/02/
voltage-gated-calcium-channel-and-pharmacogenetic-
association-with-adverse-cardiovascular-outcomes-
hypertension-treatment-with-verapamil-sr-ccb-vs-
atenolol-bb-or-trandolapril-ace/
      SNPs in apoE are found to influence statin response
significantly. Less frequent variants in
PCSK9 and smaller effect sizes in SNPs in HMGCR
http://pharmaceuticalintelligence.com/2014/01/02/snps-in-apoe-are-found-to-influence-statin-response-significantly-less-frequent-variants-in-pcsk9-and-smaller-effect-sizes-in-snps-in-hmgcr/

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Curation, HealthCare System in the US, and Calcium Signaling Effects on Cardiac Contraction, Heart Failure, and Atrial Fibrillation, and the Relationship of Calcium Release at the Myoneural Junction to Beta Adrenergic Release

Posted in Accountable Care Organizations, Affordable Care Act, Atherogenic Processes & Pathology, Best evidence, Bio Instrumentation in Experimental Life Sciences Research, Biomarkers & Medical Diagnostics, Ca2+ triggered activation, Ca2+ triggered activation, Calcium Signaling, Calmodulin, Calmodulin Kinase and Contraction, Cardiac muscle regeneration, Cardiomyopathy, Cardiovascular Pharmacogenomics, Cardiovascular Research, Cell Biology, Signaling & Cell Circuits, Congenital Heart Disease, Curation, Curation methodology, Cytoskeleton, De novo synthesis, Dialectic, Discovery process, Disease Biology, Small Molecules in Development of Therapeutic Drugs, Evolutionary cognition, Experimental validation, Explanatory, Federal Budget Appropriations, Frontiers in Cardiology and Cardiovascular Disorders, Genome Biology, Health Economics and Outcomes Research, Healthcare costs and reimbursement, HealthCare IT, Healthcare Reform, Historical relevance, HTN, Indigent Nutrition, Ionic Transporters Na+, K, Medical Devices R&D Investment, Medical Imaging Technology, Image Processing/Computing, MRI, CT, Nuclear Medicine, Ultra Sound, Medicare and Medicaid, Myocardial metabolism, Myocardial ischemia, myocardial perfusion, Myocardial adenine nucleotide metabolism, Na-K transport, Na-K-ATPase, Neurohumoral Transmission, Nitric Oxide in Health and Disease, Nutritional Supplements: Atherogenesis, lipid metabolism, Origins of Cardiovascular Disease, Pharmacotherapy of Cardiovascular Disease, PKC, Population Health Management, Genetics & Pharmaceutical, Pre-Clinical Animal Model Development, Regenerative Biology and Medicine, Skilled Nursing Facilities, Stem Cells for Regenerative Medicine, Synaptic vesicle, Technology Advance Assessment of, Technology Capital Expenses, Technology Transfer: Biotech and Pharmaceutical, Theoretic convergence, Translational Effectiveness, Translational Research, Translational Science, Uninsured and Underinsured, tagged , , , , , , , , , , , , , , , , , , , , , , , , , , , , , on January 2, 2014| Leave a Comment »

Curation, HealthCare System in the US, and Calcium Signaling Effects on Cardiac Contraction, Heart Failure, and Atrial Fibrillation, and the Relationship of Calcium Release at the Myoneural Junction to Beta Adrenergic Release

Curator and e-book Contributor: Larry H. Bernstein, MD, FCAP
Curator and BioMedicine e-Series Editor-in-Chief: Aviva Lev Ari, PhD, RN

and 

Content Consultant to Six-Volume e-SERIES A: Cardiovascular Diseases: Justin Pearlman, MD, PhD, FACC

This portion summarises what we have covered and is now familiar to the reader.  There are three related topics, and an extension of this embraces other volumes and chapters before and after this reading.  This approach to the document has advantages over the multiple authored textbooks that are and have been pervasive as a result of the traditional publication technology.  It has been stated by the founder of ScoopIt, that amount of time involved is considerably less than required for the original publications used, but the organization and construction is a separate creative process.  In these curations we amassed on average five articles in one curation, to which, two or three curators contributed their views.  There were surprises, and there were unfulfilled answers along the way.  The greatest problem that is being envisioned is the building a vision that bridges and unmasks the hidden “dark matter” between the now declared “OMICS”, to get a more real perspective on what is conjecture and what is actionable.  This is in some respects unavoidable because the genome is an alphabet that is matched to the mino acid sequences of proteins, which themselves are three dimensional drivers of sequences of metabolic reactions that can be altered by the accumulation of substrates in critical placements, and in addition, the proteome has functional proteins whose activity is a regulatory function and not easily identified.  In the end, we have to have a practical conception, recognizing the breadth of evolutionary change, and make sense of what we have, while searching for more.

We introduced the content as follows:

1. We introduce the concept of curation in the digital context, and it’s application to medicine and related scientific discovery.

Topics were chosen were used to illustrate this process in the form of a pattern, which is mostly curation, but is significantly creative, as it emerges in the context of this e-book.

  • Alternative solutions in Treatment of Heart Failure (HF), medical devices, biomarkers and agent efficacy is handled all in one chapter.
  • PCI for valves vs Open heart Valve replacement
  • PDA and Complications of Surgery — only curation could create the picture of this unique combination of debate, as exemplified of Endarterectomy (CEA) vs Stenting the Carotid Artery (CAS), ischemic leg, renal artery stenosis.

2. The etiology, or causes, of cardiovascular diseases consist of mechanistic explanations for dysfunction relating to the heart or vascular system. Every one of a long list of abnormalities has a path that explains the deviation from normal. With the completion of the analysis of the human genome, in principle all of the genetic basis for function and dysfunction are delineated. While all genes are identified, and the genes code for all the gene products that constitute body functions, there remains more unknown than known.

3. Human genome, and in combination with improved imaging methods, genomics offers great promise in changing the course of disease and aging.

4. If we tie together Part 1 and Part 2, there is ample room for considering clinical outcomes based on individual and organizational factors for best performance. This can really only be realized with considerable improvement in information infrastructure, which has miles to go.

Curation

Curation is an active filtering of the web’s  and peer reviewed literature found by such means – immense amount of relevant and irrelevant content. As a result content may be disruptive. However, in doing good curation, one does more than simply assign value by presentation of creative work in any category. Great curators comment and share experience across content, authors and themes.
Great curators may see patterns others don’t, or may challenge or debate complex and apparently conflicting points of view.  Answers to specifically focused questions comes from the hard work of many in laboratory settings creatively establishing answers to definitive questions, each a part of the larger knowledge-base of reference. There are those rare “Einstein’s” who imagine a whole universe, unlike the three blindmen of the Sufi tale.  One held the tail, the other the trunk, the other the ear, and they all said this is an elephant!
In my reading, I learn that the optimal ratio of curation to creation may be as high as 90% curation to 10% creation. Creating content is expensive. Curation, by comparison, is much less expensive.  The same source says “Scoop.it is my content marketing testing “sandbox”. In sharing, he says that comments provide the framework for what and how content is shared.

Healthcare and Affordable Care Act

We enter year 2014 with the Affordable Care Act off to a slow start because of the implementation of the internet signup requiring a major repair, which is, unfortunately, as expected for such as complex job across the US, and with many states unwilling to participate.  But several states – California, Connecticut, and Kentucky – had very effective state designed signups, separate from the federal system.  There has been a very large rush and an extension to sign up. There are many features that we can take note of:

1. The healthcare system needed changes because we have the most costly system, are endowed with advanced technology, and we have inexcusable outcomes in several domains of care, including, infant mortality, and prenatal care – but not in cardiology.

2. These changes that are notable are:

  • The disparities in outcome are magnified by a large disparity in highest to lowest income bracket.
  • This is also reflected in educational status, and which plays out in childhood school lunches, and is also affected by larger class size and cutbacks in school programs.
  • This is not  helped by a large paralysis in the two party political system and the three legs of government unable to deal with work and distraction.
  • Unemployment is high, and the banking and home construction, home buying, and rental are in realignment, but interest rates are problematic.

3.  The  medical care system is affected by the issues above, but the complexity is not to be discounted.

  •  The medical schools are unable at this time to provide the influx of new physicians needed, so we depend on a major influx of physicians from other countries
  • The technology for laboratories, proteomic and genomic as well as applied medical research is rejuvenating the practice in cardiology more rapidly than any other field.
  • In fields that are imaging related the life cycle of instruments is shorter than the actual lifetime use of the instruments, which introduces a shortening of ROI.
  • Hospitals are consolidating into large consortia in order to maintain a more viable system for referral of specialty cases, and also is centralizing all terms of business related to billing.
  • There is reduction in independent physician practices that are being incorporated into the hospital enterprise with Part B billing under the Physician Organization – as in Partners in Greater Boston, with the exception of “concierge” medical practices.
  • There is consolidation of specialty laboratory services within state, with only the most specialized testing going out of state (Quest, LabCorp, etc.)
  • Medicaid is expanded substantially under the new ACA.
  • The federal government as provider of services is reducing the number of contractors for – medical devices, diabetes self-testing, etc.
  • The current rearrangements seeks to provide a balance between capital expenses and fixed labor costs that it can control, reduce variable costs (reagents, pharmaceutical), and to take in more patients with less delay and better performance – defined by outside agencies.

Cardiology, Genomics, and calcium ion signaling and ion-channels in cardiomyocyte function in health and disease – including heart failure, rhythm abnormalities, and the myoneural release of neurotransmitter at the vesicle junction.

This portion is outlined as follows:

2.1 Human Genome: Congenital Etiological Sources of Cardiovascular Disease

2.2 The Role of Calcium in Health and Disease

2.3 Vasculature and Myocardium: Diagnosing the Conditions of Disease

Genomics & Genetics of Cardiovascular Disease Diagnoses

actin cytoskeleton

wall stress, ventricular workload, contractile reserve

Genetic Base of Atherosclerosis and Loss of Arterial Elasticity with Aging

calcium and actin skeleton, signaling, cell motility

hypertension & vascular compliance

Genetics of Conduction Disease

Ca+ stimulated exostosis: calmodulin & PKC (neurotransmitter)

complications & MVR

disruption of Ca2+ homeostasis cardiac & vascular smooth muscle

synaptotagmin as Ca2+ sensor & vesicles

atherosclerosis & ion channels


It is increasingly clear that there are mutations that underlie many human diseases, and this is true of the cardiovascular system.  The mutations are mistakes in the insertion of a purine nucleotide, which may or may not have any consequence.  This is why the associations that are being discovered in research require careful validation, and even require demonstration in “models” before pursuing the design of pharmacological “target therapy”.  The genomics in cardiovascular disease involves very serious congenital disorders that are asserted early in life, but the effects of and development of atherosclerosis involving large and medium size arteries has a slow progression and is not dominated by genomic expression.  This is characterized by loss of arterial elasticity. In addition there is the development of heart failure, which involves the cardiomyocyte specifically.  The emergence of regenerative medical interventions, based on pleuripotent inducible stem cell therapy is developing rapidly as an intervention in this sector.

Finally, it is incumbent on me to call attention to the huge contribution that research on calcium (Ca2+) signaling has made toward the understanding of cardiac contraction and to the maintenance of the heart rhythm.  The heart is a syncytium, different than skeletal and smooth muscle, and the innervation is by the vagus nerve, which has terminal endings at vesicles which discharge at the myocyte junction.  The heart specifically has calmodulin kinase CaMK II, and it has been established that calmodulin is involved in the calcium spark that triggers contraction.  That is only part of the story.  Ion transport occurs into or out of the cell, the latter termed exostosis.  Exostosis involves CaMK II and pyruvate kinase (PKC), and they have independent roles.  This also involves K+-Na+-ATPase.  The cytoskeleton is also discussed, but the role of aquaporin in water transport appears elsewhere, as the transport of water between cells.  When we consider the Gibbs-Donnan equilibrium, which precedes the current work by a century, we recall that there is an essential balance between extracellular Na+ + Ca2+ and the intracellular K+ + Mg2+, and this has been superceded by an incompletely defined relationship between ions that are cytoplasmic and those that are mitochondrial.  The glass is half full!

 

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Elastin Arteriopathy: The Genetics of Supravalvular Aortic Stenosis

Posted in Aortic Valve: TAVR, TAVI vs Open Heart Surgery, Cardiac and Cardiovascular Surgical Procedures, Cardiovascular Research, Chemical Genetics, Computational Biology/Systems and Bioinformatics, Congenital Heart Disease, Frontiers in Cardiology and Cardiovascular Disorders, Genome Biology, Genomic Testing: Methodology for Diagnosis, Human Sensation and Cellular Transduction: Physiology and Therapeutics, Medical and Population Genetics, Origins of Cardiovascular Disease, Personalized and Precision Medicine & Genomic Research, Pharmacogenomics, Pharmacotherapy of Cardiovascular Disease, Population Health Management, Genetics & Pharmaceutical, Proteomics, Valves & Tools, tagged , , , on December 30, 2013| Leave a Comment »

Elastin Arteriopathy: The Genetics of Supravalvular Aortic Stenosis

Reporter: Aviva Lev-Ari, PhD, RN

 

Supravalvular Aortic Stenosis Elastin Arteriopathy

Giuseppe Merla, PhD, Nicola Brunetti-Pierri, MD, Pasquale Piccolo, PhD, Lucia Micale, PhD and Maria Nicla Loviglio, PhD, MSc

Author Affiliations

From the Medical Genetics Unit, IRCCS Casa Sollievo Della Sofferenza Hospital, San Giovanni Rotondo, Italy (G.M., L.M., M.N.L.); Telethon Institute of Genetics and Medicine, Napoli, Italy (N.B-P., P.P.); Department of Pediatrics, Federico II University of Naples, Naples, Italy (N.B-P.); and CIG Center for Integrative Genomics, University of Lausanne, Lausanne, Switzerland (M.N.L.).

Correspondence to Giuseppe Merla, PhD, Medical Genetics Unit, IRCCS Casa Sollievo della Sofferenza, viale Cappuccini, 71013 San Giovanni Rotondo, Italy. E-mailg.merla@operapadrepio.it

Abstract

Supravalvular aortic stenosis is a systemic elastin (ELN) arteriopathy that disproportionately affects the supravalvular aorta. ELN arteriopathy may be present in a nonsyndromic condition or in syndromic conditions such as Williams–Beuren syndrome. The anatomic findings include congenital narrowing of the lumen of the aorta and other arteries, such as branches of pulmonary or coronary arteries. Given the systemic nature of the disease, accurate evaluation is recommended to establish the degree and extent of vascular involvement and to plan appropriate interventions, which are indicated whenever hemodynamically significant stenoses occur. ELN arteriopathy is genetically heterogeneous and occurs as a consequence of haploinsufficiency of the ELN gene on chromosome 7q11.23, owing to either microdeletion of the entire chromosomal region or ELN point mutations. Interestingly, there is a prevalence of premature termination mutations resulting in null alleles among ELN point mutations. The identification of the genetic defect in patients with supravalvular aortic stenosis is essential for a definitive diagnosis, prognosis, and genetic counseling.

SOURCE:

Circulation: Cardiovascular Genetics.2012; 5: 692-696

doi: 10.1161/ CIRCGENETICS.112.962860

 

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LDL, HDL, TG, ApoA1 and ApoB: Genetic Loci Associated With Plasma Concentration of these Biomarkers – A Genome-Wide Analysis With Replication

Posted in Atherogenic Processes & Pathology, Biological Networks, Gene Regulation and Evolution, Biomarkers & Medical Diagnostics, Biomedical Measurement Science, Cardiovascular Research, Cell Biology, Signaling & Cell Circuits, Chemical Biology and its relations to Metabolic Disease, Chemical Genetics, Computational Biology/Systems and Bioinformatics, Congenital Heart Disease, Frontiers in Cardiology and Cardiovascular Disorders, Genome Biology, Genomic Testing: Methodology for Diagnosis, HTN, Medical and Population Genetics, Origins of Cardiovascular Disease, Personalized and Precision Medicine & Genomic Research, Pharmacogenomics, Population Health Management, Genetics & Pharmaceutical, Population Health Management, Nutrition and Phytochemistry, Proteomics, Statistical Methods for Research Evaluation, tagged , , , , , , , , on December 18, 2013| Leave a Comment »

LDL, HDL, TG, ApoA1 and ApoB: Genetic Loci Associated With Plasma Concentration of these Biomarkers – A Genome-Wide Analysis With Replication

Reporter: Aviva Lev-Ari, PhD, RN

Genetic Loci Associated With Plasma Concentration of Low-Density Lipoprotein Cholesterol, High-Density Lipoprotein Cholesterol, Triglycerides, Apolipoprotein A1, and Apolipoprotein B Among 6382 White Women in Genome-Wide Analysis With Replication

Daniel I. Chasman, PhD*, Guillaume Paré, MD, MS*, Robert Y.L. Zee, PhD, MPH, Alex N. Parker, PhD, Nancy R. Cook, ScD, Julie E. Buring, ScD, David J. Kwiatkowski, MD, PhD, Lynda M. Rose, MS, Joshua D. Smith, BS, Paul T. Williams, PhD, Mark J. Rieder, PhD, Jerome I. Rotter, MD, Deborah A. Nickerson, PhD, Ronald M. Krauss, MD,Joseph P. Miletich, MD and Paul M Ridker, MD, MPH

Author Affiliations

From the Center for Cardiovascular Disease Prevention (D.I.C., G.P., R.Y.L.Z., N.R.C., J.E.B., L.M.R., P.M.R.) and Donald W. Reynolds Center for Cardiovascular Research (D.I.C., G.P., R.Y.L.Z., N.R.C., D.J.K., P.M.R.), Brigham and Women’s Hospital, Harvard Medical School, Boston, Mass; Amgen, Inc, Cambridge, Mass (A.N.P., J.M.P.); Department of Genome Sciences, University of Washington, Seattle, Wash (J.D.S., M.J.R., D.A.N.); Life Science Division, Lawrence Berkeley National Laboratory, Berkeley, Calif (P.T.W., R.M.K.); Medical Genetics Institute, Cedars-Sinai Medical Center, Los Angeles, Calif (J.I.R.); and Children’s Hospital Oakland Research Institute, Oakland, Calif (R.M.K.).

Correspondence to Daniel I. Chasman, Center for Cardiovascular Disease Prevention, Brigham and Women’s Hospital, 900 Commonwealth Ave E, Boston, MA 02215. E-mail dchasman@rics.bwh.harvard.edu

Abstract

Background— Genome-wide genetic association analysis represents an opportunity for a comprehensive survey of the genes governing lipid metabolism, potentially revealing new insights or even therapeutic strategies for cardiovascular disease and related metabolic disorders.

Methods and Results— We have performed large-scale, genome-wide genetic analysis among 6382 white women with replication in 2 cohorts of 970 additional white men and women for associations between common single-nucleotide polymorphisms and low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, triglycerides, apolipoprotein (Apo) A1, and ApoB. Genome-wide associations (P<5×10−8) were found at the PCSK9 gene, the APOB gene, the LPLgene, the APOA1-APOA5 locus, the LIPC gene, the CETP gene, the LDLR gene, and the APOE locus. In addition, genome-wide associations with triglycerides at the GCKRgene confirm and extend emerging links between glucose and lipid metabolism. Still other genome-wide associations at the 1p13.3 locus are consistent with emerging biological properties for a region of the genome, possibly related to the SORT1 gene. Below genome-wide significance, our study provides confirmatory evidence for associations at 5 novel loci with low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, or triglycerides reported recently in separate genome-wide association studies. The total proportion of variance explained by common variation at the genome-wide candidate loci ranges from 4.3% for triglycerides to 12.6% for ApoB.

Conclusion— Genome-wide associations at the GCKR gene and near the SORT1gene, as well as confirmatory associations at 5 additional novel loci, suggest emerging biological pathways for lipid metabolism among white women.

 SOURCE:

Circulation: Cardiovascular Genetics.2008; 1: 21-30

doi: 10.1161/ CIRCGENETICS.108.773168

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Atrioventricular (AV) Conduction Disease (block): Human Mutations affecting the Voltage Clock

Posted in Cardiovascular Research, Chemical Genetics, Computational Biology/Systems and Bioinformatics, Congenital Heart Disease, Electrophysiology, Frontiers in Cardiology and Cardiovascular Disorders, Genome Biology, Origins of Cardiovascular Disease, Population Health Management, Genetics & Pharmaceutical, Proteomics, tagged , , , , , on December 18, 2013| Leave a Comment »

Atrioventricular (AV) Conduction Disease (block): Human Mutations affecting the Voltage Clock

Reporter: Aviva Lev-Ari, PhD, RN

Human mutations affecting the voltage clock

  • (SCN5A and HCN4),

  • calcium clock (RYR2 and CASQ2), or both mechanisms

  • (ANKB) have been identified that negatively affect sinus node function.37,38

Diseases of Conduction Block Conduction block can occur at any level of the cardiac conduction system (CCS) and can manifest as sinoatrial exit block, atrioventricular block, infra-Hisian block, or bundle branch block. Impaired conduction can be caused by ion channel defects that alter action potential shape or by defective coupling between cardiomyocytes. Inherited defects in cardiac conduction have been linked to mutations in SCN5A and SCN1B (both affect phase 0) and KCNJ2 (affects phase 3 and 4). 

The cardiac sodium channel consists of the pore-forming α-subunit (encoded by SCN5A) and a modulatory β-subunit (encoded by SCN1B). The α-subunit contains a voltage sensor that allows for rapid activation in response to membrane depolarization. After depolarization, the sodium channel undergoes a period of inactivation, in which it is refractory to further impulses. SCN5A requires membrane repolarization to relieve the inactivated state. The inward rectifier potassium channel, Kir2.1, encoded by KCNJ2, maintains the resting membrane potential. Therefore, proper functioning of Nav1.5 and Kir2.1 is necessary for normal cardiac excitability.

SCN5A

Progressive cardiac conduction defect, or Lev-Lenègre disease, is characterized by age-related, fibrosclerotic degeneration of the His-Purkinje system.6 Impulse propagation through the proximal ventricular conduction system progressively declines, resulting in bundle branch blocks and eventually complete atrioventricular block. An inherited form of Lev-Lenègre disease is associated with loss of function mutations in SCN5A and can exist alone or as overlap syndromes with Brugada or long QT syndrome 3.6 Inherited progressive cardiac conduction defect is associated with a high risk of complete atrioventricular block and Stoke-Adams syncope without ventricular dysrhythmia.7 Schott et al8 identified a mutation in SCN5A that cosegregates with Lenègre disease in a large French family. Affected individuals had variable degrees of conduction block requiring pacemaker implantation in 4 family members because of syncope or complete heart block. Linkage analysis and candidate gene sequencing identified a T>C substitution at position +2 of the donor splice site of intron 22 (IVS22+2 T>C), which results in a mutant lacking the voltage-sensitive segment.8 Functional analysis demonstrated no transient inward sodium current in response to depolarization, consistent with a loss-of-function mutation.6

SCN1B

The majority of patients with Brugada and conduction disease do not have SCN5Amutations. Therefore, modifiers of Nav1.5 expression or function have become the target of candidate gene sequencing approaches. Watanabe et al9 identified SCN1B mutations in 3 families with conduction disease with or without Brugada syndrome. Coexpression of mutant β-subunits with Nav1.5 resulted in diminished sodium current.

KCNJ2

Mutations in KCNJ2 have been found in a rare autosomal dominant condition called Andersen-Tawil syndrome, characterized by periodic paralysis, dysmorphic features, polymorphic ventricular tachycardia, and cardiac conduction disease.10,11 ECG evaluation of 96 patients with Andersen-Tawil syndrome from 33 unrelated kindreds revealed conduction defects at multiple levels from the atrioventricular node to the distal conduction system.55 Cardiomyocytes expressing a dominant-negative subunit of Kir2.1 exhibited a 95% reduction in IK1, resulting in significant action potential prolongation. Mouse models of Andersen-Tawil syndrome exhibited a slower heart rate and significant slowing of conduction.56,57

Therapeutic Strategies

The current standard of care for symptomatic bradycardia due to conduction system disease is the implantation of an electronic pacemaker. Despite their success, electronic pacemakers have limitations, which include lead complications, finite battery life, potential for infection, lack of autonomic responsiveness, and size restriction in younger patients. These limitations have spurred on the development of biological pacemakers, the premise of which is to restore pacemaking activity with the use of viral-based or stem cell–based gene delivery systems.99 The identification and characterization of genes involved in generating pacemaker currents have allowed biological pacemaker technology to become a reality.

The restoration of sinus pacing rates can be achieved by modulating inward and outward currents to establish or increase the slope of diastolic depolarization in cardiac tissue. Increasing inward currents and/or decreasing outward currents increase the slope of diastolic depolarization and therefore the pacing rate. Genes that have been investigated or are under current investigation include the following: (1) β2-adrenergic receptor,100,101(2) dominant-negative Kir2.1 mutants,102 (3) adenylate cyclase type VI (ACVI),103,104and (4) HCN channels.105 The β2-adrenergic receptor and adenylate cyclase type VI both increase cAMP levels, leading to activation of endogenous HCN channels and calcium clock mechanisms. Although initial animal models using the β2-adrenergic receptor showed promise with transient increases in heart rate, the potential for proarrhythmia and the inability of this approach to establish de novo pacemaker activity limited its efficacy.101

Another approach focused on modifying ionic currents that convert working myocardial cells, which have relatively stable diastolic potentials, into cells with phase 4 diastolic depolarization. It was postulated that atrial and ventricular myocytes have the potential for automaticity, but that hyperpolarizing currents, such as IK1, prevent diastolic depolarization by stabilizing the resting membrane potential. Miake et al102 confirmed this hypothesis when they demonstrated that adenoviral delivery of a dominant-negative Kir2.1 construct into the left ventricle of guinea pigs resulted in conversion of quiescent myocytes into pacemaker cells. Unfortunately, significant action potential prolongation limited the clinical utility of this treatment strategy.102

Rosen and colleagues105,106 demonstrated that automaticity could be induced in quiescent myocardium with the use of heterologous expression of HCN channels that produce the pacemaker current If. Qu and Plotnikov et al demonstrated that stable autonomous rhythms could be generated when adenovirus encoding HCN2 was injected into the left atrium105 or left bundle branch106 of a canine heart. To bypass the limitations of viral-based systems, such as host immune response, several groups reported the successful use of cell-based delivery systems. Plotnikov et al107 reported the successful implantation of human mesenchymal stem cells expressing HCN2 in the left ventricle of a canine model of atrioventricular block. Dogs maintained stable ectopic pacemaker activity for >6 weeks without the use of immunosuppression.107 Human mesenchymal stem cells electronically couple to host myocardium through gap junctions; therefore, conditions with significant gap junction remodeling may affect the efficacy of this method.

Although standalone biological pacemakers may be far into the future, adjuvant biological pacemakers may find real-world utility for current deficiencies of electronic pacemakers, such as limited battery life and device infections. For example, biological preparations used in conjunction with device therapy may be used to extend battery life, decreasing the frequency of generator changes. Transient injectable pacemakers may also function as bridge therapy after lead extraction of an infected device. The need for adjuvant biological pacemakers is clear, but continued refinement of gene- and cell-based delivery systems will be necessary to make this technology a reality.99

Conclusion

Although rare, inherited arrhythmias have become an invaluable tool in identifying the genetic determinants of CCS function. Each new mutation enhances our understanding and appreciation of the biochemical and structural complexity needed for cardiac impulse generation and propagation. This methodology is hampered, however, by the relative scarcity of inherited conditions affecting the CCS. The addition of genome-wide association studies has broadened this search for novel genes beyond rare familial afflictions to include common, multifactorial conditions. It is hoped that this exciting new frontier will bring to light the complex interplay of genes and genetic/epigenetic modifiers that influence the prevalence of common diseases. These genetic screens will ultimately yield a bevy of new gene targets for pharmaceutical or gene-based therapeutics of the future.

REFERENCES

http://circ.ahajournals.org/content/123/8/904 [Circulation.2011; 123: 904-915 doi: 10.1161/​CIRCULATIONAHA.110.942284]

http://www.ncbi.nlm.nih.gov/pubmed/15372490

 

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