A recent study by several HCM genetics researchers around the globe, led by Australia’s Dr. Jodie Ingles, found that 2/3 of genetic mutations previously reported to patients as HCM causative may actually NOT trigger HCM.
A recent study conducted in the U.K. evaluated whether the anti-anginal drug trimetazidine would improve symptoms and exercise capacity for those patients with non-obstructive hypertrophic cardiomyopathy.
Unfortunately, this study which was conducted by Dr. Perry Elliott and his colleagues at University College London, found that trimetatazidine did not improve exercise capacity in these patients. Following the results of this study, trimetazidine will now join ranolazine and spironolactone in the compost heap of drugs which tried and failed to improve HCM symptoms. While a third drug, perhexiline, was found to improve symptoms for non-obstructive HCM, its limitations, including potentially serious side effects, stand in the way of its common usage.
In a companion editorial to this study entitled “Non-Obstructive Hypertrophic Cardiomyopathy-the High Hanging Fruit,” Dr. Sharlene Day of the University of Michigan’s HCM Center discusses the difficulties seen in drug trials related to non-obstructive HCM.
This article, by Drs. Julio Panza and Srihari Naidu of New York’s Westchester Medical Center, describes early efforts to diagnose, categorize and treat hypertrophic cardiomyopathy, while explaining how these methods have evolved over time. A very interesting and informative read.
In May of this year, HCMBeat published this interview with Yale’s Dr. Daniel Jacoby and Dr. Nikolaos Papoutsidakis about their online survey of HCM patients who engage in risk-taking activities.
In this conversation, Drs. Jacoby and Papoutsidakis emphasized that the shared decision making process is an important facet of the patient/physician relationship for HCM patients. Risks should be explained, and decisions made with each patient’s set of values and priorities in mind. The doctors hoped that the results from their study would help to inform the shared decision-making process as applied to activities that involve any amount of patient risk-taking.
After analyzing data from 633 patients (282 men and 351 women), 556 patients reported participating in thrill-seeking activities, while 331 continued such participation after their HCM diagnosis. The doctors found that only 33.6% of the patients who engaged in the thrill-seeking activities experienced such minor adverse events as dizziness, nausea, palpitations or chest pain, while only .02% experienced significant events during or within an hour following the activity. Only one ICD shock was reported.
Hence, the doctors concluded that the risks associated with such activities appear to be low.
MyoKardia is collaborating with 23andMe, a genetic testing company which provides ancestry and health information directly to consumers, to create an online patient community intended to advance research efforts related to hypertrophic cardiomyopathy. The companies plan to allow 23andMe customers access to the latest information about HCM, as well as the opportunity to participate in research.
The companies will use a custom designed survey to collect baseline and follow-up data from HCM patients. They are hopeful that this collaboration will yield unique insights into HCM.
Research findings gained through the collaboration will be shared with HCM patients through the 23andMe platform. Currently more than 6,000 HCM patients are customers of 23andMe
More details of the collaboration can be found:
DISCLOSURES: HCMBeat has received unrestricted educational grants from MyoKardia. Additionally, Cynthia Burstein Waldman of HCMBeat serves as a Patient Advisor on the Steering Committee for MyoKardia’s Explorer trial.
MD Magazine has a nice feature about Dr. Robert Battle of the University of Virginia’s HCM Center. Read it here.
A recent paper published in the journal Circulation looked at the clinical course of approximately 4,600 HCM patients over the course of more than 24,000 clinical years, which the paper describes as the largest comprehensive cohort of HCM patients ever studied.
This study examined patients from eight high volume HCM centers which aggregated their institutional data into a database known as the Sarcomere Human Cardiomyopathy Registry (or the acronym the “SHaRe” for short). The results of the study showed that, in general, HCM patients are at substantially elevated risk for atrial fibrillation and heart failure, and have significantly higher mortality rates than that of the general U.S. population.
A recent study by doctors at the Cleveland Clinic suggests that the presence of late gadolinium enhancement (LGE) should be added to the various risk factors currently used to assess patients who are at low or intermediate risk of sudden death. The presence and balancing of these risk factors are used by patients and doctors to determine the need for implantable cardiac defibrillators (ICDs). LGE is an indication of cardiac scar tissue and can be seen on cardiac MRI scans. This study recommended that LGE comprising a total of 15% or more of left ventricular mass be used as an additional risk factor. The study found that this indicator worked equally well when applied to both obstructed and non-obstructive HCM patients.
Interestingly, an earlier but recent study published by Cleveland Clinic doctors found that the risk factors currently in use to determine the need for an ICD fall short as applied to patients with the obstructive form of HCM.
Risk factors in common use today have been propounded by the American College of CardiologyAmerican Heart Association (ACC/AHA) in the U.S., while a different set of guideline and a mathematical risk calculator was promulgated more recently in Europe by the European Society of Cardiology (ESC). You can find more about the ACC/AHA and ESC guidelines here.
A second and related finding of this study by the Cleveland Clinic, known for its large HCM program and high volume of myectomies, was that patients who undego myectomy appear to experience a protective effect from their surgeries. Even when found to have 25% or more LGE, patients in this study who previously underwent myectomy experienced a lower than expected rate of adverse events.
A recent study by doctors at the Cleveland Clinic found that current guidelines used to assess risk of sudden cardiac death (SCD) in HCM fall short when applied to the population of patients with the obstructive form of HCM (HOCM).
The study looked at both the European Society of Cardiology (ESC) and American College of Cardiology (ACC)/American Heart Association (AHA) guidelines, and found that both sets of guidelines came up short in predicting SCD. In particular, the study found that patients who had previously undergone myectomy had a reduced risk of SCD that is not accounted for in existing risk models.
Conversely, the study found that patients with atrial fibrillation had a higher risk of SCD, which is also not reflected in the existing risk models.
A companion editorial by Dr. Harzell Schaff of the Mayo Clinic explains the likely reasons for the myectomy findings, while a second accompanying editorial by Dr. John Jefferies of Cincinnatti Children’s Hospital (who has recently accepted an appointment at the U. of Tennessee Health Science Center in Memphis) maintains that the ESC and ACC/AHA guidelines should be changed to reflect the lower SCD risk following myectomy.