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Posts Tagged ‘American College of Cardiology ACC’

Diagnostic Value of Cardiac Biomarkers


Diagnostic Value of Cardiac Biomarkers

Author and Curator: Larry H Bernstein, MD, FCAP 

These presentations covered several views of the utilization of cardiac markers that have evolved for over 60 years.  The first stage was the introduction of enzymatic assays and isoenzyme measurements to distinguish acute hepatitis and acute myocardial infarction, which included lactate dehydrogenase (LD isoenzymes 1, 2) at a time that late presentation of the patient in the emergency rooms were not uncommon, with the creatine kinase isoenzyme MB declining or disappeared from the circulation.  The world health organization (WHO) standard definition then was the presence of two of three:

1. Typical or atypical precordial pressure in the chest, usually with radiation to the left arm

2. Electrocardiographic changes of Q-wave, not previously seen, definitive; ST- elevation of acute myocardial injury with repolarization;
T-wave inversion.

3. The release into the circulation of myocardial derived enzymes –
creatine kinase – MB (which was adapted to measure infarct size), LD-1,
both of which were replaced with troponins T and I, which are part of the actomyosin contractile apparatus.

The research on infarct size elicited a major research goal for early diagnosis and reduction of infarct size, first with fibrinolysis of a ruptured plaque, and this proceeded into the full development of a rapidly evolving interventional cardiology as well as cardiothoracic surgery, in both cases, aimed at removal of plaque or replacement of vessel.  Surgery became more imperative for multivessel disease, even if only one vessel was severely affected.

So we have clinical history, physical examination, and emerging biomarkers playing a large role for more than half a century.  However, the role of biomarkers broadened.  Patients were treated with antiplatelet agents, and a hypercoagulable state coexisted with myocardial ischemic injury.  This made the management of the patient reliant on long term followup for Warfarin with the international normalized ratio (INR) for a standardized prothrombin time (PT), and reversal of the PT required transfusion with thawed fresh frozen plasma (FFP).  The partial thromboplastin test (PPT) was necessary in hospitalization to monitor the heparin effect.

Thus, we have identified the use of traditional cardiac biomarkers for:

1. Diagnosis
2. Therapeutic monitoring

The story is only the beginning.  Many patients who were atypical in presentation, or had cardiovascular ischemia without plaque rupture were problematic.  This led to a concerted effort to redesign the troponin assays for high sensitivity with the concern that the circulation should normally be free of a leaked structural marker of myocardial damage. But of course, there can be a slow leak or a decreased rate of removal of such protein from the circulation, and the best example of this would be the patient with significant renal insufficiency, as TnT is clear only through the kidney, and TNI is clear both by the kidney and by vascular endothelium.  The introduction of the high sensitivity assay has been met with considerable confusion, and highlights the complexity of diagnosis in heart disease.  Another test that is used for the diagnosis of heart failure is in the class of natriuretic peptides (BNP, pro NT-BNP, and ANP), the last of which has been under development.

While there is an exponential increase in the improvement of cardiac devices and discovery of pharmaceutical targets, the laboratory support for clinical management is not mature.  There are miRNAs that may prove valuable, matrix metalloprotein(s), and potential endothelial and blood cell surface markers, they require

1. codevelopment with new medications
2. standardization across the IVD industry
3. proficiency testing applied to all laboratories that provide testing
4. the measurement  on multitest automated analyzers with high capability in proteomic measurement  (MS, time of flight, MS-MS)

nejmra1216063_f1   Atherosclerotic Plaques Associated with Various Presentations               nejmra1216063_f2     Inflammatory Pathways Predisposing Coronary Arteries to Rupture and Thrombosis.        atherosclerosis progression

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The Cost to Value Conundrum in Cardiovascular Healthcare Provision


The Cost to Value Conundrum in Cardiovascular Healthcare Provision

Author: Larry H. Bernstein, MD, FCAP

I write this introduction to Volume 2 of the e-series on Cardiovascular Diseases, which curates the basic structure and physiology of the heart, the vasculature, and related structures, e.g., the kidney, with respect to:

1. Pathogenesis
2. Diagnosis
3. Treatment

Curation is an introductory portion to Volume Two, which is necessary to introduce the methodological design used to create the following articles. More needs not to be discussed about the methodology, which will become clear, if only that the content curated is changing based on success or failure of both diagnostic and treatment technology availability, as well as the systems needed to support the ongoing advances.  Curation requires:

  • meaningful selection,
  • enrichment, and
  • sharing combining sources and
  • creation of new synnthesis

Curators have to create a new perspective or idea on top of the existing media which supports the content in the original. The curator has to select from the myriad upon myriad options available, to re-share and critically view the work. A search can be overwhelming in size of the output, but the curator has to successfully pluck the best material straight out of that noise.

Part 1 is a highly important treatment that is not technological, but about the system now outdated to support our healthcare system, the most technolog-ically advanced in the world, with major problems in the availability of care related to economic disparities.  It is not about technology, per se, but about how we allocate healthcare resources, about individuals’ roles in a not full list of lifestyle maintenance options for self-care, and about the important advances emerging out of the Affordable Care Act (ACA), impacting enormously on Medicaid, which depends on state-level acceptance, on community hospital, ambulatory, and home-care or hospice restructuring, which includes the reduction of management overhead by the formation of regional healthcare alliances, the incorporation of physicians into hospital-based practices (with the hospital collecting and distributing the Part B reimbursement to the physician, with “performance-based” targets for privileges and payment – essential to the success of an Accountable Care Organization (AC)).  One problem that ACA has definitively address is the elimination of the exclusion of patients based on preconditions.  One problem that has been left unresolved is the continuing existence of private policies that meet financial capabilities of the contract to provide, but which provide little value to the “purchaser” of care.  This is a holdout that persists in for-profit managed care as an option.  A physician response to the new system of care, largely fostered by a refusal to accept Medicaid, is the formation of direct physician-patient contracted care without an intermediary.

In this respect, the problem is not simple, but is resolvable.  A proposal for improved economic stability has been prepared by Edward Ingram. A concern for American families and businesses is substantially addressed in a macroeconomic design concept, so that financial services like housing, government, and business finance, savings and pensions, boosting confidence at every level giving everyone a better chance of success in planning their personal savings and lifetime and business finances.

http://macro-economic-design.blogspot.com/p/book.html

Part 2 is a collection of scientific articles on the current advances in cardiac care by the best trained physicians the world has known, with mastery of the most advanced vascular instrumentation for medical or surgical interventions, the latest diagnostic ultrasound and imaging tools that are becoming outdated before the useful lifetime of the capital investment has been completed.  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.  Why should this be?  Because for generations of IT support systems, they are historically focused on billing and have made insignificant inroads into the front-end needs of the clinical staff.

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American Association of Clinical Endocrinologists (AACE) can’t support the new cardiovascular risk guidelines issued by the American Heart Association (AHA) and the American College of Cardiology (ACC)

Reporter: Aviva Lev-Ari,PhD, RN

Endocrinology Group Rejects New AHA/ACC CVD Guidelines

Miriam E. Tucker

December 13, 2013

The American Association of Clinical Endocrinologists (AACE) says it can’t support the new cardiovascular risk guidelines issued by the American Heart Association (AHA) and the American College of Cardiology (ACC), saying the set of 4 guideline documents is out of step with its own recommendations.

“AACE was asked to review and endorse the obesity and cholesterol guidelines. After careful consideration by the appropriate scientific committees of our organization, AACE declined to endorse these new cholesterol and obesity guidelines,” the organization said in a statement that was sent to its members in November and forwarded to the media today. “There are multiple reasons for this decision, including, principally, the incompatibility of these new guidelines with our existing guidelines.”

The 4 guidelines are:

All of the guidelines were issued with the support of the National Heart, Lung and Blood Institute, which had last updated its Adult Treatment Panel 3 (ATP3) National Cholesterol Education Panel (NCEP) guidelines for cholesterol and lipid management in 2004. AACE had “generally agreed” with those guidelines.

AACE welcomes the intent of the AHA and ACC in the creation of these new guidelines but cannot endorse them.

The endocrinology group faults the new AHA/ACC guidelines for focusing exclusively on randomized clinical trials and for not including studies published since 2011. “They are highly restrictive regarding the database considered and omit much new information… Taken together, these actions have resulted in a considerable number of at-risk patients being omitted from consideration.”

And, AACE says that the new cardiovascular disease calculator that was published along with the guidelines—and generated the most controversy—is already outdated. “It is based upon outmoded data, does not model the totality of the US population, has not been validated, and therefore has only limited applicability.”

As for new lipid guidelines, AACE disagrees with removal of the LDL targets and the idea that statin therapy alone is sufficient for all at-risk patients, noting that many who have multiple risk factors, including diabetes and established heart disease, will need additional therapies.

Finally, the new obesity guidelines, AACE says, “fail to classify obesity as a disease and continue the paradigm of [body-mass-index] BMI-centric risk stratification, both of which are contrary to recently stated AACE positions.” In addition, newly FDA-approved weight-loss medications are not included.

The statement concludes, “AACE welcomes the intent of the AHA and ACC in the creation of these new guidelines but does not agree with the complete content and therefore cannot endorse them.”

SOURCE

http://www.medscape.com/viewarticle/817810?nlid=42483_2105&src=wnl_edit_medp_card&uac=93761AJ&spon=2

 

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