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Archive for the ‘Acute Myocardial Infarction’ Category


Artificial Intelligence and Cardiovascular Disease

Reporter and Curator: Dr. Sudipta Saha, Ph.D.

 

Cardiology is a vast field that focuses on a large number of diseases specifically dealing with the heart, the circulatory system, and its functions. As such, similar symptomatologies and diagnostic features may be present in an individual, making it difficult for a doctor to easily isolate the actual heart-related problem. Consequently, the use of artificial intelligence aims to relieve doctors from this hurdle and extend better quality to patients. Results of screening tests such as echocardiograms, MRIs, or CT scans have long been proposed to be analyzed using more advanced techniques in the field of technology. As such, while artificial intelligence is not yet widely-used in clinical practice, it is seen as the future of healthcare.

 

The continuous development of the technological sector has enabled the industry to merge with medicine in order to create new integrated, reliable, and efficient methods of providing quality health care. One of the ongoing trends in cardiology at present is the proposed utilization of artificial intelligence (AI) in augmenting and extending the effectiveness of the cardiologist. This is because AI or machine-learning would allow for an accurate measure of patient functioning and diagnosis from the beginning up to the end of the therapeutic process. In particular, the use of artificial intelligence in cardiology aims to focus on research and development, clinical practice, and population health. Created to be an all-in-one mechanism in cardiac healthcare, AI technologies incorporate complex algorithms in determining relevant steps needed for a successful diagnosis and treatment. The role of artificial intelligence specifically extends to the identification of novel drug therapies, disease stratification or statistics, continuous remote monitoring and diagnostics, integration of multi-omic data, and extension of physician effectivity and efficiency.

 

Artificial intelligence – specifically a branch of it called machine learning – is being used in medicine to help with diagnosis. Computers might, for example, be better at interpreting heart scans. Computers can be ‘trained’ to make these predictions. This is done by feeding the computer information from hundreds or thousands of patients, plus instructions (an algorithm) on how to use that information. This information is heart scans, genetic and other test results, and how long each patient survived. These scans are in exquisite detail and the computer may be able to spot differences that are beyond human perception. It can also combine information from many different tests to give as accurate a picture as possible. The computer starts to work out which factors affected the patients’ outlook, so it can make predictions about other patients.

 

In current medical practice, doctors will use risk scores to make treatment decisions for their cardiac patients. These are based on a series of variables like weight, age and lifestyle. However, they do not always have the desired levels of accuracy. A particular example of the use of artificial examination in cardiology is the experimental study on heart disease patients, published in 2017. The researchers utilized cardiac MRI-based algorithms coupled with a 3D systolic cardiac motion pattern to accurately predict the health outcomes of patients with pulmonary hypertension. The experiment proved to be successful, with the technology being able to pick-up 30,000 points within the heart activity of 250 patients. With the success of the aforementioned study, as well as the promise of other researches on artificial intelligence, cardiology is seemingly moving towards a more technological practice.

 

One study was conducted in Finland where researchers enrolled 950 patients complaining of chest pain, who underwent the centre’s usual scanning protocol to check for coronary artery disease. Their outcomes were tracked for six years following their initial scans, over the course of which 24 of the patients had heart attacks and 49 died from all causes. The patients first underwent a coronary computed tomography angiography (CCTA) scan, which yielded 58 pieces of data on the presence of coronary plaque, vessel narrowing and calcification. Patients whose scans were suggestive of disease underwent a positron emission tomography (PET) scan which produced 17 variables on blood flow. Ten clinical variables were also obtained from medical records including sex, age, smoking status and diabetes. These 85 variables were then entered into an artificial intelligence (AI) programme called LogitBoost. The AI repeatedly analysed the imaging variables, and was able to learn how the imaging data interacted and identify the patterns which preceded death and heart attack with over 90% accuracy. The predictive performance using the ten clinical variables alone was modest, with an accuracy of 90%. When PET scan data was added, accuracy increased to 92.5%. The predictive performance increased significantly when CCTA scan data was added to clinical and PET data, with accuracy of 95.4%.

 

Another study findings showed that applying artificial intelligence (AI) to the electrocardiogram (ECG) enables early detection of left ventricular dysfunction and can identify individuals at increased risk for its development in the future. Asymptomatic left ventricular dysfunction (ALVD) is characterised by the presence of a weak heart pump with a risk of overt heart failure. It is present in three to six percent of the general population and is associated with reduced quality of life and longevity. However, it is treatable when found. Currently, there is no inexpensive, noninvasive, painless screening tool for ALVD available for diagnostic use. When tested on an independent set of 52,870 patients, the network model yielded values for the area under the curve, sensitivity, specificity, and accuracy of 0.93, 86.3 percent, 85.7 percent, and 85.7 percent, respectively. Furthermore, in patients without ventricular dysfunction, those with a positive AI screen were at four times the risk of developing future ventricular dysfunction compared with those with a negative screen.

 

In recent years, the analysis of big data database combined with computer deep learning has gradually played an important role in biomedical technology. For a large number of medical record data analysis, image analysis, single nucleotide polymorphism difference analysis, etc., all relevant research on the development and application of artificial intelligence can be observed extensively. For clinical indication, patients may receive a variety of cardiovascular routine examination and treatments, such as: cardiac ultrasound, multi-path ECG, cardiovascular and peripheral angiography, intravascular ultrasound and optical coherence tomography, electrical physiology, etc. By using artificial intelligence deep learning system, the investigators hope to not only improve the diagnostic rate and also gain more accurately predict the patient’s recovery, improve medical quality in the near future.

 

The primary issue about using artificial intelligence in cardiology, or in any field of medicine for that matter, is the ethical issues that it brings about. Physicians and healthcare professionals prior to their practice swear to the Hippocratic Oath—a promise to do their best for the welfare and betterment of their patients. Many physicians have argued that the use of artificial intelligence in medicine breaks the Hippocratic Oath since patients are technically left under the care of machines than of doctors. Furthermore, as machines may also malfunction, the safety of patients is also on the line at all times. As such, while medical practitioners see the promise of artificial technology, they are also heavily constricted about its use, safety, and appropriateness in medical practice.

 

Issues and challenges faced by technological innovations in cardiology are overpowered by current researches aiming to make artificial intelligence easily accessible and available for all. With that in mind, various projects are currently under study. For example, the use of wearable AI technology aims to develop a mechanism by which patients and doctors could easily access and monitor cardiac activity remotely. An ideal instrument for monitoring, wearable AI technology ensures real-time updates, monitoring, and evaluation. Another direction of cardiology in AI technology is the use of technology to record and validate empirical data to further analyze symptomatology, biomarkers, and treatment effectiveness. With AI technology, researchers in cardiology are aiming to simplify and expand the scope of knowledge on the field for better patient care and treatment outcomes.

 

References:

 

https://www.news-medical.net/health/Artificial-Intelligence-in-Cardiology.aspx

 

https://www.bhf.org.uk/informationsupport/heart-matters-magazine/research/artificial-intelligence

 

https://www.medicaldevice-network.com/news/heart-attack-artificial-intelligence/

 

https://www.nature.com/articles/s41569-019-0158-5

 

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5711980/

 

www.j-pcs.org/article.asp

http://www.onlinejacc.org/content/71/23/2668

http://www.scielo.br/pdf/ijcs/v30n3/2359-4802-ijcs-30-03-0187.pdf

 

https://www.escardio.org/The-ESC/Press-Office/Press-releases/How-artificial-intelligence-is-tackling-heart-disease-Find-out-at-ICNC-2019

 

https://clinicaltrials.gov/ct2/show/NCT03877614

 

https://www.europeanpharmaceuticalreview.com/news/82870/artificial-intelligence-ai-heart-disease/

 

https://www.frontiersin.org/research-topics/10067/current-and-future-role-of-artificial-intelligence-in-cardiac-imaging

 

https://www.news-medical.net/health/Artificial-Intelligence-in-Cardiology.aspx

 

https://www.sciencedaily.com/releases/2019/05/190513104505.htm

 

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Society for Cardiovascular Angiography and Interventions (SCAI) Released Classification Stages of Cardiogenic Shock

Reporter: Aviva Lev-Ari, PhD, RN
NEWS | CARDIOGENIC SHOCK | MAY 20, 2019

SCAI Releases New Consensus Document on Classification Stages of Cardiogenic Shock

New classification system endorsed by multiple societies was developed to describe five stages of shock

SCAI Releases New Consensus Document on Classification Stages of Cardiogenic Shock

Image courtesy of the Society for Cardiovascular Angiography and Interventions (SCAI).

May 20, 2019 – A newly released expert consensus statement proposes a classification schema for cardiogenic shock (CS) that will facilitate communication in both the clinical and research settings. The document was published online in the Society for Cardiovascular Angiography and Interventions (SCAI)’s Catheterization and Cardiovascular Interventions journal,1 and is endorsed by the American College of Cardiology, American Heart Association, the Society of Critical Care Medicine and the Society of Thoracic Surgeons.

Cardiogenic shock is a condition in which the heart, often abruptly, cannot pump enough blood to meet the body’s needs, according to the Mayo Clinic, most often accompanying larger heart attacks such as myocardial infarction (MI). Outcomes for patients with cardiogenic shock complicating MI have not significantly improved over the last 30 years despite the development of various percutaneous mechanical circulatory support technologies and the national standard of emergent angioplasty and stenting.

SCAI convened a multidisciplinary writing group comprised of leading experts in interventionaland advanced heart failure, non-invasive cardiology, emergency medicine, critical care and cardiac nursing to represent the team-based care of these patients. The writing group developed a new five-stage system that is defined by narrative patient descriptions, physical findings, and biochemical/hemodynamic markers, creating a new language that will facilitate rapid assessment, reassessment over time and communication between providers including hospital systems.

The new CS definition is intended to provide clinicians and researchers with a unified and standardized vocabulary that will translate across all settings. Additionally, the definition aims to facilitate recognition of risk for adverse outcomes and the potential benefit from various interventions and prognosis. The goal is to reduce mortality on both an individual and national scale.

“The main areas we may have failed in the fight to improve mortality in cardiogenic shock is, quite simply, not speaking the same language when describing these patients,” said Srihari S. Naidu, M.D., FSCAI, former SCAI Trustee and chair of the writing group. “Without that, we can’t even begin to understand these patients, how sick they are, what might work and what does not work. This is the most important first step, and it is important to use this classification system to reset our understanding of cardiogenic shock and restart the trials very much needed in this space.”

For more information: http://www.scai.org

Related Cardiogenic Shock Content

VIDEO: Cardiogenic Shock Case with Impella CP Support

VIDEO: Analysis of Outcomes for 15,259 U.S. Patients with AMICS Supported with the Impella Device

VIDEO: How to Reduce Cardiogenic Shock Mortality by 50 Percent

Reference

1. Baran D.A., Grines C.L., Bailey S., et al. SCAI clinical expert consensus statement on the classification of cardiogenic shock. Catheterization and Cardiovascular Interventions, May 19, 2019. https://doi.org/10.1002/ccd.28329

SOURCE

https://www.dicardiology.com/content/scai-releases-new-consensus-document-classification-stages-cardiogenic-shock?eid=333021707&bid=2450760

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@Cleveland Clinic – Serial measurements of high-sensitivity C-reactive protein (hsCRP) post acute coronary syndrome (ACS) may help identify patients at higher risk for morbidity and mortality

 

Reporter: Aviva Lev-Ari, PhD, RN

 

Original Investigation
March 6, 2019

Association of Initial and Serial C-Reactive Protein Levels With Adverse Cardiovascular Events and Death After Acute Coronary Syndrome, A Secondary Analysis of the VISTA-16 Trial

Key Points

Question  Are initial and serial increases in high-sensitivity C-reactive protein levels after acute coronary syndrome in medically optimized patients associated with increased risk of a major cardiac event, cardiovascular death, and all-cause death?

Findings  In this secondary analysis of the VISTA-16 randomized clinical trial that included 5145 patients, baseline and longitudinal high-sensitivity C-reactive protein levels were independently associated with increased risk of a major adverse cardiac event, cardiovascular death, and all-cause death during the 16-week follow-up.

Meaning  Monitoring high-sensitivity C-reactive protein levels in patients after acute coronary syndrome may help better identify patients at greater risk for recurrent cardiovascular events or death.

Abstract

Importance  Higher baseline high-sensitivity C-reactive protein (hsCRP) levels after an acute coronary syndrome (ACS) are associated with adverse cardiovascular outcomes. The usefulness of serial hsCRP measurements for risk stratifying patients after ACS is not well characterized.

Objective  To assess whether longitudinal increases in hsCRP measurements during the 16 weeks after ACS are independently associated with a greater risk of a major adverse cardiac event (MACE), all-cause death, and cardiovascular death.

Results  Among 4257 patients in this study, 3141 (73.8%) were men and the mean age was 60.3 years (interquartile range [IQR], 53.5-67.8 years). The median 16-week low-density lipoprotein cholesterol level was 64.9 mg/dL (IQR, 50.3-82.3 mg/dL), and the median hsCRP level was 2.4 mg/L (IQR, 1.1-5.2 mg/L). On multivariable analysis, higher baseline hsCRP level (hazard ratio [HR], 1.36 [95% CI, 1.13-1.63]; P = .001) and higher longitudinal hsCRP level (HR, 1.15 [95% CI, 1.09-1.21]; P < .001) were independently associated with MACE. Similar significant and independent associations were shown between baseline and longitudinal hsCRP levels and cardiovascular death (baseline: HR, 1.61 per SD [95% CI, 1.07-2.41], P = .02; longitudinal: HR, 1.26 per SD [95% CI, 1.19-1.34], P < .001) and between baseline and longitudinal hsCRP levels and all-cause death (baseline: HR, 1.58 per SD [95% CI, 1.07-2.35], P = .02; longitudinal: HR, 1.25 per SD [95% CI, 1.18-1.32], P < .001).

Conclusions and Relevance  Initial and subsequent increases in hsCRP levels during 16 weeks after ACS were associated with a greater risk of the combined MACE end point, cardiovascular death, and all-cause death despite established background therapies. Serial measurements of hsCRP during clinical follow-up after ACS may help to identify patients at higher risk for mortality and morbidity.

SOURCE

https://jamanetwork.com/journals/jamacardiology/fullarticle/2725734

 

Inflammation’s role in residual risk

Residual risk of cardiovascular events or death remains high following ACS, despite coronary revascularization and optimal guideline-directed treatment with antiplatelet and LDL cholesterol-lowering agents. Inflammation is thought to drive this risk, but no effective treatment for such inflammation is commercially available. The secretory phospholipase A2 inhibitor varespladib was developed to meet this need, and it was evaluated in VISTA-16.

VISTA-16 was an international, multicenter clinical trial that randomized 5,145 patients in a double-blind manner to varespladib or placebo on a background of atorvastatin treatment within 96 hours of presentation with ACS. The trial was terminated early due to futility and likely harm from the drug, which was subsequently pulled from development.

Implications for practice

The association of increasing CRP levels with residual cardiovascular risk may prompt more intensive treatment to lower this risk. In particular, a secondary analysis showed that use of antiplatelet agents (clopidogrel, ticlopidine and prasugrel) was associated with stable or decreasing hsCRP levels.

“Monitoring not only lipids but also hsCRP after ACS may help us better identify patients at increased risk for recurrent cardiovascular events or death,” notes Dr. Puri. “High or increasing CRP levels could be an indication to optimize dual antiplatelet therapy post-ACS, along with high-intensity statin therapy (and possibly PCSK9 inhibitors) and antihypertensive therapy, in addition to instituting measures that are globally beneficial, such as dietary modifications and cardiac rehabilitation/exercise.”

SOURCE

https://consultqd.clevelandclinic.org/increasing-inflammation-correlates-with-residual-risk-after-acute-coronary-syndrome/amp/?__twitter_impression=true

 

Other related articles published in this Open Access Online Scientific Journal, include the following:

 

Biomarkers and risk factors for cardiovascular events, endothelial dysfunction, and thromboembolic complications

Larry H Bernstein, MD, FCAP, Curator

https://pharmaceuticalintelligence.com/2014/09/09/biomarkers-and-risk-factors-for-cardiovascular-events-endothelial-dysfunction-and-thromboembolic-complications/

 

A Concise Review of Cardiovascular Biomarkers of Hypertension

Curator: Larry H. Bernstein, MD, FCAP

https://pharmaceuticalintelligence.com/2016/04/25/a-concise-review-of-cardiovascular-biomarkers-of-hypertension/

 

Acute Coronary Syndrome (ACS): Strategies in Anticoagulant Selection: Diagnostics Approaches – Genetic Testing Aids vs. Biomarkers (Troponin types and BNP)

Curator: Aviva Lev-Ari, PhD, RN

https://pharmaceuticalintelligence.com/2018/03/13/acute-coronary-syndrome-acs-strategies-in-anticoagulant-selection-diagnostics-approaches-genetic-testing-aids-vs-biomarkers-troponin-types-and-bnp/

 

In Europe, BigData@Heart aim to improve patient outcomes and reduce societal burden of atrial fibrillation (AF), heart failure (HF) and acute coronary syndrome (ACS).

Reporter: Aviva Lev-Ari, PhD, RN

https://pharmaceuticalintelligence.com/2017/07/10/in-europe-bigdataheart-aim-to-improve-patient-outcomes-and-reduce-societal-burden-of-atrial-fibrillation-af-heart-failure-hf-and-acute-coronary-syndrome-acs/

 

Cardiovascular Diseases and Pharmacological Therapy: Curations by Aviva Lev-Ari, PhD, RN, 2006 – 4/2018

https://pharmaceuticalintelligence.com/2014/04/17/cardiovascular-diseases-and-pharmacological-therapy-curations-by-aviva-lev-ari-phd-rn/

 

 

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Changes in Levels of Sex Hormones and N-Terminal Pro–B-Type Natriuretic Peptide as Biomarker for Cardiovascular Diseases

Reporter and Curator: Dr. Sudipta Saha, Ph.D.

 

Considerable differences exist in the prevalence and manifestation of atherosclerotic cardiovascular disease (CVD) and heart failure (HF) between men and women. Premenopausal women have a lower risk of CVD and HF compared with men; however, this risk increases after menopause. Sex hormones, particularly androgens, are associated with CVD risk factors and events and have been postulated to mediate the observed sex differences in CVD.

 

B-type natriuretic peptides (BNPs) are secreted from cardiomyocytes in response to myocardial wall stress. BNP plays an important role in cardiovascular remodelling and volume homeostasis. It exerts numerous cardioprotective effects by promoting vasodilation, natriuresis, and ventricular relaxation and by antagonizing fibrosis and the effects of the renin-angiotensin-aldosterone system. Although the physiological role of BNP is cardioprotective, pathologically elevated N-terminal pro–BNP (NT-proBNP) levels are used clinically to indicate left ventricular hypertrophy, dysfunction, and myocardial ischemia. Higher NT-proBNP levels among individuals free of clinical CVD are associated with an increased risk of incident CVD, HF, and cardiovascular mortality.

 

BNP and NT-proBNP levels are higher in women than men in the general population. Several studies have proposed the use of sex- and age-specific reference ranges for BNP and NT-proBNP levels, in which reference limits are higher for women and older individuals. The etiology behind this sex difference has not been fully elucidated, but prior studies have demonstrated an association between sex hormones and NT-proBNP levels. Recent studies measuring endogenous sex hormones have suggested that androgens may play a larger role in BNP regulation by inhibiting its production.

 

Data were collected from a large, multiethnic community-based cohort of individuals free of CVD and HF at baseline to analyze both the cross-sectional and longitudinal associations between sex hormones [total testosterone (T), bioavailable T, freeT, dehydroepiandrosterone (DHEA), SHBG, and estradiol] and NT-proBNP, separately for women and men. It was found that a more androgenic pattern of sex hormones was independently associated with lower NT-proBNP levels in cross-sectional analyses in men and postmenopausal women.

 

This association may help explain sex differences in the distribution of NT-proBNP and may contribute to the NP deficiency in men relative to women. In longitudinal analyses, a more androgenic pattern of sex hormones was associated with a greater increase in NT-proBNP levels in both sexes, with a more robust association among women. This relationship may reflect a mechanism for the increased risk of CVD and HF seen in women after menopause.

 

Additional research is needed to further explore whether longitudinal changes in NT-proBNP levels seen in our study are correlated with longitudinal changes in sex hormones. The impact of menopause on changes in NT-proBNP levels over time should also be explored. Furthermore, future studies should aim to determine whether sex hormones directly play a role in biological pathways of BNP synthesis and clearance in a causal fashion. Lastly, the dual role of NTproBNP as both

  • a cardioprotective hormone and
  • a biomarker of CVD and HF, as well as
  • the role of sex hormones in delineating these processes,

should be further explored. This would provide a step toward improved clinical CVD risk stratification and prognostication based on

  • sex hormone and
  • NT-proBNP levels.

 

References:

 

https://www.medpagetoday.com/clinical-connection/cardio-endo/76480?xid=NL_CardioEndoConnection_2018-12-27

 

https://www.ncbi.nlm.nih.gov/pubmed/30137406

 

https://www.ncbi.nlm.nih.gov/pubmed/22064958

 

https://www.ncbi.nlm.nih.gov/pubmed/24036936

 

https://www.ncbi.nlm.nih.gov/pubmed/19854731

 

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UPDATED on 2/25/2019

https://www.medpagetoday.com/cardiology/prevention/78202?xid=nl_mpt_SRCardiology_2019-02 25&eun=g99985d0r&utm_source=Sailthru&utm_medium=email&utm_campaign=CardioUpdate_022519&utm_term=NL_Spec_Cardiology_Update_Active

 

ICER announced plans to look at icosapent ethyl (Vascepa) and rivaroxaban (Xarelto) as add-on therapies in cardiovascular disease.

Heart attack risk is rising among young women. But NHANES data show women are still ahead of men on control of hypertension, diabetes, and cholesterol. (Circulation)

Two Classes of Antithrombotic Drugs: Anticoagulants and Antiplatelet drugs

Reporter: Aviva Lev-Ari, PhD, RN
These drugs are used to treat
  • strokes,
  • myocardial infarctions,
  • pulmonary embolisms,
  • disseminated intravascular coagulation (DIC) and
  • deep vein thrombosis (DVT)
— all potentially life-threatening conditions.
THERAPEUTIC STRATEGIES
• Degrade fibrinogen/fibrin (fibrinolytic agents)
GOAL: eliminate formed clots
• Inhibit clotting mechanism (anticoagulants)
GOAL: prevent progression of thrombosis
• Interfere either with platelet adhesion and/or aggregation (antiplatelet drugs)
GOAL: prevent initial clot formation
Antithrombotic therapy has had an enormous impact in several significant ways.
  • Heparin has made bypass surgery and dialysis possible by blocking clotting in external tubing.
  • Antithrombotic therapy has reduced the risk of blood clots in leg veins (also known as deep-vein thrombosis or DVT), a condition that can lead to death from pulmonary embolism (a clot that blocks an artery to the lungs) by more than 70 percent. And most importantly,
  • it has markedly reduced death from heart attacks, the risk of stroke in people with heart irregularities (atrial fibrillation), and the risk of major stroke in patients with mini-strokes.

Antithrombotic Therapy

This article was published in December 2008 as part of the special ASH anniversary brochure, 50 Years in Hematology: Research That Revolutionized Patient Care.

Normally, blood flows through our arteries and veins smoothly and efficiently, but if a clot, or thrombus, blocks the smooth flow of blood, the result – called thrombosis – can be serious and even cause death. Diseases arising from clots in blood vessels include heart attack and stroke, among others. These disorders collectively are the most common cause of death and disability in the developed world. We now have an array of drugs that can be used to prevent and treat thrombosis – and there are more on the way – but this was not always the case.

Classes of Antithrombotic Drugs

Image Source: http://www.hematology.org/About/History/50-Years/1523.aspx

The most important components of a thrombus are fibrin and platelets. Fibrin is a protein that forms a mesh that traps red blood cells, while platelets, a type of blood cell, form clumps that add to the mass of the thrombus. Both fibrin and platelets stabilize the thrombus and prevent it from falling apart. Fibrin is the more important component of clots that form in veins, and platelets are the more important component of clots that form in arteries where they can cause heart attacks and strokes by blocking the flow of blood in the heart and brain, respectively, although fibrin plays an important role in arterial thrombosis as well.

There are two classes of antithrombotic drugs: anticoagulants and antiplatelet drugs. Anticoagulants slow down clotting, thereby reducing fibrin formation and preventing clots from forming and growing. Antiplatelet agents prevent platelets from clumping and also prevent clots from forming and growing.

Anticoagulant Drugs

The anticoagulants heparin and dicumarol were discovered by chance, long before we understood how they worked. Heparin was first discovered in 1916 by a medical student at The Johns Hopkins University who was investigating a clotting product from extracts of dog liver and heart. In 1939, dicumarol (the precursor to warfarin) was extracted by a biochemist at the University of Wisconsin from moldy clover brought to him by a farmer whose prize bull had bled to death after eating the clover.

Both of these anticoagulants have been used effectively to prevent clots since 1940. These drugs produce a highly variable anticoagulant effect in patients, requiring their effect to be measured by special blood tests and their dose adjusted according to the results. Heparin acts immediately and is given intravenously (through the veins). Warfarin is swallowed in tablet form, but its anticoagulant effect is delayed for days. Therefore, until recently, patients requiring anticoagulants who were admitted to a hospital were started on a heparin infusion and were then discharged from the hospital after five to seven days on warfarin.

In the 1970s, three different groups of researchers in Stockholm, London, and Hamilton, Ontario, began work on low-molecular-weight heparin (LMWH). LMWH is produced by chemically splitting heparin into one-third of its original size. It has fewer side effects than heparin and produces a more predictable anticoagulant response. By the mid 1980s, LMWH preparations were being tested in clinical trials, and they have now replaced heparin for most indications. Because LMWH is injected subcutaneously (under the skin) in a fixed dose without the need for anticoagulant monitoring, patients can now be treated at home instead of at the hospital.

With the biotechnology revolution has come genetically engineered “designer” anticoagulant molecules that target specific clotting enzymes. Anti-clotting substances and their DNA were also extracted from an array of exotic creatures (ticks, leeches, snakes, and vampire bats) and converted into drugs by chemical synthesis or genetic engineering. Structural chemists next began to fabricate small molecules designed to fit into the active component of clotting enzymes, like a key into a lock.

The first successful synthetic anticoagulants were fondaparinux and bivalirudin. Bivalirudin, a synthetic molecule based on the structure of hirudin (the anti-clotting substance found in leeches), is an effective treatment for patients with heart attacks. Fondaparinux is a small molecule whose structure is based on the active component of the much larger LMWH and heparin molecules. It has advantages over LMWH and heparin and has recently been approved by the FDA. Newer designer drugs that target single clotting factors and that can be taken by mouth are undergoing clinical testing. If successful, we will have safer and more convenient replacements for warfarin, the only oral anticoagulant available for more than 60 years.

Antiplatelet Drugs

Blood platelets are inactive until damage to blood vessels or blood coagulation causes them to explode into sticky irregular cells that clump together and form a thrombus. The first antiplatelet drug was aspirin, which has been used to relieve pain for more than 100 years. In the mid-1960s, scientists showed that aspirin prevented platelets from clumping, and subsequent clinical trials showed that it reduces the risk of stroke and heart attack. In 1980, researchers showed that aspirin in very low doses (much lower than that required to relieve a headache) blocked the production of a chemical in platelets that is required for platelet clumping. During that time, better understanding of the process of platelet clumping allowed the development of designer antiplatelet drugs directed at specific targets. We now have more potent drugs, such as clopidogrel, dipyridamole, and abciximab. These drugs are used with aspirin and effectively prevent heart attack and stroke; they also prolong the lives of patients who have already had a heart attack.

SOURCE 
Anticoagulation Drugs:
  • heparin (FONDAPARINUX HEPARIN (Calciparine, Hepathrom, Lipo-Hepin, Liquaemin, Panheprin)
  • warfarin – 4-HYDROXYCOUMARIN (Coumadin) WARFARIN (Athrombin-K, Panwarfin)
  • rivaroxaban (Xarelto)
  • dabigatran (Pradaxa)
  • apixaban (Eliquis)
  • edoxaban (Savaysa)
  • enoxaparin (Lovenox)
  • fondaparinux (Arixtra)
  • ARGATROBAN BIVALIRUDIN (Angiomax)
  • DALTEPARIN (Fragmin)
  • DROTRECOGIN ALFA (ACTIVATED PROTEIN C) (Xigris)
  • HIRUDIN (Desirudin)
  • LEPIRUDIN (Refludan)
  • XIMELAGATRAN (Exanta)

ANTIDOTES

  • PHYTONADIONE (Vitamin K1)
  • PROTAMINE SULFATE AMINOCAPROIC ACID (EACA) (generic, Amicar) (in bleeding disorders)
Antiplatelet Drugs
  • ACETYL SALICYLIC ACID (aspirin) 
  • clopidogrel (Plavix)
  • dipyridamole (Persantine)
  • abciximab (Centocor)
  • EPTIFIBATIDE (Integrilin)
  • TICLOPIDINE (Ticlid)
  • TIROFIBAN (Aggrastat)

THROMBOLYTICS

  1. ANISTREPLASE (APSAC; Eminase)
  2. STREPTOKINASE (Streptase, Kabikinase)
  3. TISSUE PLASMINOGEN ACTIVATORS (tPAs):
  • ALTEPLASE (Activase),
  • RETEPLASE (Retavase),
  • TENECTEPLASE (TNKase)
  • UROKINASE (Abbokinase)

Fibrinolytic Drugs

Fibrinolytic therapy is used in selected patients with venous thromboembolism. For example, patients with massive or submassive PE can benefit from systemic or catheter-directed fibrinolytic therapy. The latter can also be used as an adjunct to anticoagulants for treatment of patients with extensive iliofemoral-vein thrombosis.

Arterial and venous thrombi are composed of platelets and fibrin, but the proportions differ.

  • Arterial thrombi are rich in platelets because of the high shear in the injured arteries. In contrast,
  • venous thrombi, which form under low shear conditions, contain relatively few platelets and are predominantly composed of fibrin and trapped red cells.
  • Because of the predominance of platelets, arterial thrombi appear white, whereas venous thrombi are red in color, reflecting the trapped red cells.

SOURCE

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Reporter and Curator: Dr. Sudipta Saha, Ph.D.

 

A heart-healthy diet has been the basis of atherosclerotic cardiovascular disease (ASCVD) prevention and treatment for decades. The potential cardiovascular (CV) benefits of specific individual components of the “food-ome” (defined as the vast array of foods and their constituents) are still incompletely understood, and nutritional science continues to evolve.

 

The scientific evidence base in nutrition is still to be established properly. It is because of the complex interplay between nutrients and other healthy lifestyle behaviours associated with changes in dietary habits. However, several controversial dietary patterns, foods, and nutrients have received significant media exposure and are stuck by hype.

 

Decades of research have significantly advanced our understanding of the role of diet in the prevention and treatment of ASCVD. The totality of evidence includes randomized controlled trials (RCTs), cohort studies, case-control studies, and case series / reports as well as systematic reviews and meta-analyses. Although a robust body of evidence from RCTs testing nutritional hypotheses is available, it is not feasible to obtain meaningful RCT data for all diet and health relationships.

 

Studying preventive diet effects on ASCVD outcomes requires many years because atherosclerosis develops over decades and may be cost-prohibitive for RCTs. Most RCTs are of relatively short duration and have limited sample sizes. Dietary RCTs are also limited by frequent lack of blinding to the intervention and confounding resulting from imperfect diet control (replacing 1 nutrient or food with another affects other aspects of the diet).

 

In addition, some diet and health relationships cannot be ethically evaluated. For example, it would be unethical to study the effects of certain nutrients (e.g., sodium, trans fat) on cardiovascular disease (CVD) morbidity and mortality because they increase major risk factors for CVD. Epidemiological studies have suggested associations among diet, ASCVD risk factors, and ASCVD events. Prospective cohort studies yield the strongest observational evidence because the measurement of dietary exposure precedes the development of the disease.

 

However, limitations of prospective observational studies include: imprecise exposure quantification; co-linearity among dietary exposures (e.g., dietary fiber tracks with magnesium and B vitamins); consumer bias, whereby consumption of a food or food category may be associated with non-dietary practices that are difficult to control (e.g., stress, sleep quality); residual confounding (some non-dietary risk factors are not measured); and effect modification (the dietary exposure varies according to individual/genetic characteristics).

 

It is important to highlight that many healthy nutrition behaviours occur with other healthy lifestyle behaviours (regular physical activity, adequate sleep, no smoking, among others), which may further confound results. Case-control studies are inexpensive, relatively easy to do, and can provide important insight about an association between an exposure and an outcome. However, the major limitation is how the study population is selected or how retrospective data are collected.

 

In nutrition studies that involve keeping a food diary or collecting food frequency information (i.e., recall or record), accurate memory and recording of food and nutrient intake over prolonged periods can be problematic and subject to error, especially before the diagnosis of disease.

 

The advent of mobile technology and food diaries may provide opportunities to improve accuracy of recording dietary intake and may lead to more robust evidence. Finally, nutrition science has been further complicated by the influences of funding from the private sector, which may have an influence on nutrition policies and practices.

 

So, the future health of the global population largely depends on a shift to healthier dietary patterns. Green leafy vegetables and antioxidant suppliments have significant cardio-protective properties when consumed daily. Plant-based proteins are significantly more heart-healthy compared to animal proteins.

 

However, in the search for the perfect dietary pattern and foods that provide miraculous benefits, consumers are vulnerable to unsubstantiated health benefit claims. As clinicians, it is important to stay abreast of the current scientific evidence to provide meaningful and effective nutrition guidance to patients for ASCVD risk reduction.

 

Available evidence supports CV benefits of nuts, olive oil and other liquid vegetable oils, plant-based diets and plant-based proteins, green leafy vegetables, and antioxidant-rich foods. Although juicing may be of benefit for individuals who would otherwise not consume adequate amounts of fresh fruits and vegetables, caution must be exercised to avoid excessive calorie intake. Juicing of fruits / vegetables with pulp removal increases calorie intake. Portion control is necessary to avoid weight gain and thus cardiovascular health.

 

There is currently no evidence to supplement regular intake of antioxidant dietary supplements. Gluten is an issue for those with gluten-related disorders, and it is important to be mindful of this in routine clinical practice; however, there is no evidence for CV or weight loss benefits, apart from the potential caloric restriction associated with a gluten free diet.

 

References:

 

https://www.ncbi.nlm.nih.gov/pubmed/28254181

 

https://www.sciencedirect.com/science/article/pii/S0735109713060294?via%3Dihub

 

http://circ.ahajournals.org/content/119/8/1161

 

http://refhub.elsevier.com/S0735-1097(17)30036-0/sref6

 

https://www.scopus.com/record/display.uri?eid=2-s2.0-0031709841&origin=inward&txGid=af40773f7926694c7f319d91efdcd40c

 

https://www.magonlinelibrary.com/doi/10.12968/hosp.2000.61.4.1875

 

https://jamanetwork.com/journals/jamainternalmedicine/article-abstract/2548255

 

https://pharmaceuticalintelligence.com/2018/05/31/supplements-offer-little-cv-benefit-and-some-are-linked-to-harm-in-j-am-coll-cardiol/

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A new mechanism of action to attack in the treatment of coronary artery disease (CAD), Novartis developed Ilaris (canakinumab), a human monoclonal antibody targeting the interleukin-1beta innate immunity pathway

Reporter: Aviva Lev-Ari, PhD, RN

 

Speaking at an ESC press briefing, Ridker said, “This is what personalized predictive medicine is all about.” Once a patient has experienced an MI, there is always residual risk of recurrence. Thus, he suggested that residual risk can be divided into

  • residual lipid-driven risk and
  • residual inflammatory-driven risk.

canakinumab might prove to be most useful if it were given to an identified high-responder group. Findings in the hs-CRP responders:

Patients whose hs-CRP declined to 1.8 mg/L or less had a much more robust response. In that subgroup, the number needed to treat to prevent a primary endpoint event was 50 at 2 years and 30 at 3.7 years.

He noted that after a single injection responders have a significant reduction in highly sensitive-CRP and it is those patients who would benefit from continuing on treatment.

“Maybe that first dose could be free,” Ridker added.

Co-investigator, Peter Libby, MD, of Massachusetts General Hospital, put it this way: 30 days after an MI, when a patient is on statin therapy and stable,

  • physicians could check LDL and then initiate more aggressive statin therapy if it is not well-controlled. Similarly,
  • physicians should check hs-CRP, and if it is elevated — 2.0 mg/L or higher — initiating anti-inflammatory therapy targeting interleukin-1 beta would be an option

Interestingly, the treatment had no effect on lipids, which suggests that the benefit was all attributable to the anti-inflammatory activity. 

In the Canakinumab Anti-inflammatory Thrombosis Outcomes Study (CANTOS), 150 mg of canakinumab every 3 months reduced high-sensitivity C-reactive protein (hs-CRP) levels by an average of 37% compared with placebo and achieved a 15% reduction in cardiovascular events — mostly MIs — compared with placebo, Paul Ridker, MD, reported here at the European Society of Cardiology 2017 congress.

The CANTOS findings were simultaneously published online by the New England Journal of Medicine.

After a median follow-up of 3.7 years, the event rate was 4.5 per 100 person-years in the placebo group versus 3.86 events per 100 person-years in the canakinumab 150 mg group. Two other arms — canakinumab 50 mg and 300 mg — also achieved reductions in events (4.11 and 3.90 per 100 person-years, respectively) but only the 150-mg dose achieved a statistically significant reduction.

There was no reduction in mortality. The trial recruited patients who had a history of MI and a hs-CRP level of 2.0 mg/L or higher.

  • There was no significant difference in all-cause mortality (HR for all canakinumab doses versus placebo, 0.94; 95% CI 0.83-1.06; P=0.31).

Benefits of Anti-inflammatory Canakinumab

although there was no cardiovascular mortality benefit, there was 30% reduction in need for bypass surgery, angioplasty, and heart failure — all of which means a significant improvement in quality of life. And treatment was also associated with a reduction in gout, rheumatoid arthritis, and osteoarthritis, he said.

Cancer Benefit

There was an apparent decrease in risk of cancer, a finding that was elucidated in a Lancet paper also published today. In the cancer analysis, also authored by Ridker, total cancer mortality was lower only in the 300-mg group, but “[i]ncident lung cancer (n=129) was significantly less frequent in the 150 mg (HR 0.61 [95% CI 0.39–0.97]; P=0.034) and 300 mg groups (HR 0.33 [95% CI 0.18–0.59] P<0.0001.”

Negative findings

  • Canakinumab was associated with a higher incidence of fatal infection than placebo — the rate was 0.18 in the 3,344 patient placebo group versus 0.32 among the 6,717 patients who received any dose of the drug, which worked out to 23 deaths versus 78 deaths (P=0.02).
  • VIEW VIDEO

Study Author Paul M. Ridker. Interviewed by Peggy Peck, Editor-in-Chief of MedPage Today

https://www.medpagetoday.com/meetingcoverage/esc/67529

  • VIEW VIDEO

Clinical Impact or No Clinical Impact

Anthony DeMaria, MD discusses the major trials from ESC and what impact, if any, they will have on clinical practice.
Benefit vs Price
On June 28 heart failure specialist Milton Packer, MD, wrote this in his MedPage Today blog: “My prediction: [canakinumab] may cost $64,000 for a 15-20% reduction in the risk of a major cardiovascular event, without decreasing cardiovascular death by itself.
Amgen’s Repatha (evolocumab) is a PCSK9 inhibitor that aggressively lowers lipids and is approved for patients who fail statin therapy, including patients with heterozygous or homozygous familial hypercholesterolemia. But while the lipid reductions with the PCSK9 therapy are impressive, and the FOURIER trial found a 15% reduction in events with treatment, neither evolocumab nor alirocumab (Praluent), a PCSK9 inhibitor from Sanofi/Regeneron have achieved wide uptake as payers balk at the high price tags for the drugs.
Other anti-inflammatory agents:
Ridker said. For example, “we have a [National Heart, Lung, and Blood Institute] trial of methotrexate (RA agent) that is on-going. If that proves to be effective, it would be only pennies per treatment.” At the press conference, Ridker said the methotrexate trial has “randomized about 4,000 patients, and we will need to get to 7,000 so it will be a few years before we have results.”

SOURCE

https://www.medpagetoday.com/meetingcoverage/esc/67529

176 articles on monoclonal antibody

https://pharmaceuticalintelligence.com/?s=monoclonal+antibody

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