Implantable Defibrillators Help Heart Patients Live Longer

Implantable defibrillators (ICDs) have contributed to reduced mortality rates among patients with hypertrophic cardiomyopathy (HCM), according to a new study.

Researchers at the Minneapolis Heart Institute Foundation (MHIF; MN, USA) and Tufts Medical Center (Boston, MA, USA) conducted a study in 1,000 patients with HCM who received an ICD between 1992 and 2011 to examine long-term outcomes, death rates, and causes of death, including sudden cardiac death (SCD).

The results showed that while 4% of patients had died from an HCM-related death at follow-up, 6% had survived a life-threatening event, most commonly attributed to the timely intervention of the ICD. Of the 17 HCM sudden deaths, six occurred in patients who had declined a recommendation for ICD therapy, while 11 were either initially evaluated in the 1990’s—prior to general employment of ICDs for HCM—or had no risk factors to justify an ICD decision. The study was presented at the American College of Cardiology (ACC) conference, held during March 2015 in San Diego (CA, USA).

“This research changes our perceptions of HCM from a grim, unrelenting, and largely untreatable condition to a contemporary disease with effective treatment options and a low rate of death,” said lead author Barry Maron, MD, director of the HCM Center at MHIF. “Today’s treatment interventions, including ICDs for SCD prevention, have dramatically changed the outlook for these patients. They are living longer and deaths directly associated with the disease are much less common, especially those caused by SCD.”

HCM is a primary disease of the myocardium in which a portion of it becomes hypertrophic without any obvious cause, creating functional impairment of the cardiac muscle. It is a leading cause of SCD in young athletes and indeed in any age group, and a cause of disabling cardiac symptoms. HCM is frequently asymptomatic until SCD, and for this reason some suggest routinely screening certain populations for this disease, as the prevalence is about 0.2% to 0.5% of the general population.

Related Links:
Minneapolis Heart Institute Foundation
Tufts Medical Center