According to a recent paper published in Circulation, children’s risk for sudden death should be evaluated using different risk factors than those used for adults.
Two main differences seen between factors influencing the risk of sudden death of children and adults were that:
- for children, family history of sudden death was not a risk factor;
- a left ventricular outflow tract gradient in a child suggested a lower risk of sudden death.
The authors of this study propose that the risk assessment factors highlighted in this study (and not the various risk assessment tools that have been developed for adults) should be used by clinicians to evaluate the need for implantable defibrillators in children.
MyoKardia today announced positive topline results for its experimental drug mavacamten from its recent Stage 3 EXPLORER trial for patients with obstructive hypertrophic cardiomyopathy or HCM.
According to the press release, the drug met all primary and secondary endpoints, while relieving outflow tract obstruction, improving symptoms and enhancing quality of life for the patients enrolled in the trial. Furthermore, the drug was well tolerated and appeared to be free of significant side effects.
MyoKardia plans to seek FDA approval for mavacamten, the first drug specifically targeting the underlying biological mechanism of HCM, in the first quarter of 2021.
Full results of the EXPLORER study will be presented at a scientific meeting later this year.
DISCLOSURES: CYNTHIA BURSTEIN WALDMAN OF HCMBEAT SERVES AS PATIENT ADVISOR ON THE STEERING COMMITTEE OF MYOKARDIA’S EXPLORER TRIAL AND AS A MEMBER OF MYOKARDIA’S PATIENT ADVISORY BOARD.
The following guidelines have been developed by HCM specialists at the following hospitals: Brigham and Women’s Hospital in Boston, Careggi University in Florence, Italy, Stanford University, the University of Michigan and the University of Pennsylvania.
At the bottom of this page you will find the document as a pdf file which should allow you access to the links contained in the document.
Due to technical limitations, the links on the images above cannot be directly accessed, but you can download this pdf file:
COVID-19 Patient Info_institutions
and you will be able to access all links directly.
Researchers from the Sarcomere Human Cardiomyopathy Registry (or the acronym “SHaRe” for short) have again joined forces to look at a subset of hypertrophic cardiomyopathy (HCM) patients who have what is known as “end stage” HCM. This term, which is a bit of a misnomer, is used to describe patients who experience left ventricular systolic dysfunction (LVSD) which occurs when the left ventricular ejection fraction (LVEF) is less than 50%.
According to the study published last week in the journal Circulation, of a total of 6,793 HCM patients included in the study, 553 or 8% fell into this category. The paper goes on to highlight some important observations about patients that fall into this category which are highlighted below.
Predictors of HCM with Left Ventricular Systolic Dysfunction:
- increased left ventricular cavity size and wall thickness
- ejection fraction of between 50-60% (notably, patients with low normal ejection fractions were approximately 3 times more likely to develop left ventricular systolic dysfunction)
- the presence of late gadolinium enhancement on cardiac magnetic resonance imaging
- the presence of a HCM gene, particularly if located inside the thin filament genes
Factors Justifying More Aggressive Treatment for Patients with LVSD Include:
- multiple HCM gene mutations
- atrial fibrillation
- a left ventricular ejection fraction lower than 35%.
Important Takeaways From this Study:
- Patients with “end-stage” HCM do not all follow the same course. Many of the patients in this study reported no serious events for many years following their decline in ejection fraction. Thus, the term “end-stage” does not accurately reflect the majority of patients. Further research is necessary to better understand this subset of HCM patients.
- Since patients with left ventricular ejection fractions of between 50 and 59% are at heightened risk for developing end stage disease, they should be closely followed by their HCM team.
- This study found that post-myectomy patients may have a higher incidence of end stage disease. Hence, the authors suggest that patients who have undergone septal reduction therapy, especially younger patients with one or more HCM gene mutations, continue to be closely monitored by their HCM team.
Another informative article focusing on the different stages and treatments for HCM can be found here.
Findings from MyoKardia’s Phase 2 Maverick clinical trial of its experimental drug mavacamten in non-obstructive HCM were announced on Monday at the online 69th Annual Scientific Sessions of the American College of Cardiology.
Dr. Carolyn Ho of Harvard’s Brigham and Women’s Hospital reported to online viewers that mavacamten was generally well tolerated. In addition, the drug showed promising results in this Phase 2 trial intended to demonstrate the safety of the drug. In particular, some relevant additional observations were reductions in blood levels of two biomarkers of cardiac stress and injury – namely NT-proBNP which indicates hemodynamic stress, and cardiac troponin I, which is a biomarker of myocardial injury.
These findings look promising for non-obstructive HCM patients who currently have very limited treatment options.
In consultation with numerous HCM specialists across the U.S., the Hypertrophic Cardiomyopathy Association has compiled a document of guidelines for HCM patients to follow during the current coronavirus crisis.
Some of the specific recommendations are as follows:
- Patient with class 3 or 4 heart failure – specifically those with depressed ejection fractions and those awaiting transplantation – should be advised to stay close to home and minimize exposure in social gatherings.
- All patients should be encouraged to practice good personal hygiene including frequent hand washing and to use of disinfectants on all surfaces, doorknobs and banisters.
- If a HCM patient tests positive for the virus, they should contact their HCM specialist immediately in order to coordinate care with their local physicians and HCM team.
You can find the whole document here.
Additionally, the HCMA has recorded a series of informative webinars with several
HCM experts which you can find here.
A study by researchers from Mayo Clinic published this week in the Journal of the American College of Cardiology found that an artificial intelligence algorithm was able to detect hypertrophic cardiomyopathy, commonly known as HCM, from EKG results with impressive accuracy, particularly among younger patients.
In order to “teach” the computer, the researchers used digital 12-lead ECGs from 2,448 patients with HCM along with 51,153 age- and sex-matched controls. The technology was then tested on 612 HCM patients and 12,788 controls.
The findings showed that the technology was able to identify HCM in a high number of cases, even where the EKG appeared “normal” to the human eye.
The researchers believe that this technology, when refined, may prove to be an efficient tool for HCM screening in the future. The team plans to continue testing the technology in greater subject samples in order to further refine its performance.
Mayo Clinic News Network
A small study of 29 patients conducted recently in the U.K. found that the use of a biventricular pacing in patients with non-obstructive hypertrophic cardiomyopathy improved symptoms of breathlessness and improved exercise capacity as demonstrated during oxygen consumption testing.
Medications are the only treatments currently available to non-obstructed patients. The authors of this study hypothesized that biventricular pacing could be a viable way to address exercise limitations in non-obstructed patients if medications have been ineffective.
Larger trials may establish biventricular pacing as a viable treatment for non-obstructed patients in the future.
Dr. Stephen Heitner, together with his colleagues at Oregon Health & Sciences University, published an article last week in the European Journal of Heart Failure which gives a glimpse into the treatment of hypertrophic cardiomyopathy (HCM) in the future. Although recent publications have stated that the majority of HCM patients today have a favorable prognosis when receiving appropriate treatment, a heavy disease burden continues to be placed upon patients. Hence, better and more effective treatments for HCM are still needed in order to lessen this burden.
Continue reading “The Future of HCM Care”