According to a paper published last week in JAMA Cardiology, doctors at Tufts University’s HCM Center have been able to identify 95% of their patients at high risk of sudden cardiac death (SCD) from HCM. Tufts applied an updated and modified version of the risk factors enumerated in the American College of Cardiology/American Heart Association Guidelines promulgated in 2011.
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.
**Because so much HCM information was presented at the Summit, this is the second of multiple blog entries. Stay tuned to HCMBeat for more highlights from the HCM Summit. To see Part I of this series of highlights from the HCM Summit VI, click here.**
The 6th International HCM Summit was held October 27, 28 and 29th in Boston, Massachusetts. This symposium brings together HCM professionals from around the world who are there to learn about and discuss the latest developments in the treatment of HCM.
The symposium was organized by long time HCM expert Dr. Barry Maron and his son, Dr. Martin Maron. Both Marons are now affiliated with Tufts Medical Center’s Hypertrophic Cardiomyopathy Center.
What follows are summaries from selected talks presented at the meeting. The presenter and their hospital affiliation are noted below, along with the topic of their presentation. When possible, you may access the presenters’ slides via hyperlink by clicking on the name. (Note that not all presenters made their slides available).
Doctors at the University of Pennsylvania have created a new model which they say can predict the risk of sudden cardiac arrest in people without known heart disease. According to the article, published recently in Circulation, low levels of albumin, a protein commonly tested in routine blood panels, is a novel risk factor among the twelve factors identified. This article in Cardiac Rhythm News offers more details.