Both cardiac resynchronization therapy and implantable cardioverter-defibrillators reduce 2-year mortality in patients with heart failure, regardless of their racial or ethnic backgrounds, according to a report published online Aug. 18 in the Journal of the American College of Cardiology.
Guidelines contain class 1 recommendations for device therapies in the primary prevention of sudden cardiac death among patients with heart failure; cardiac resynchronization therapy (CRT) also has a class 1 recommendation for reducing the risk for events. Because of racial and ethnic disparities in the use of both therapies, as well as an underrepresentation of minorities in clinical trials of these treatments, questions have been raised as to whether black and Hispanic patients gain benefits comparable to those seen in white patients, said Dr. Boback Ziaeian of the division of cardiology at the University of California, Los Angeles, and his associates.
Dr. Ziaeian and his fellow researchers studied this issue using data from the IMPROVE HF registry (Registry to Improve the Use of Evidence-Based HF Therapies in the Outpatient Setting), a prospective observational cohort of 15,177 patients with left ventricular dysfunction and heart failure treated at 167 community and academic cardiology and multispecialty practices. Of 7,748 study participants who were eligible for ICDs/cardiac resynchronization defibrillators, 44% were non-Hispanic whites, 9% were non-Hispanic blacks, and 47% were of other racial/ethnic groups or had no race documented in their records. Of 1,188 who were eligible for cardiac resynchronization pacemakers, 50% were non-Hispanic whites, 8% were non-Hispanic blacks, and 42% were other ethnicities or had no race documented in their records.
At 2-year follow-up, 20.4% of patients who had received CRT or ICD therapy had died as compared with 27.8% of comparable patients who hadn’t received the devices, a 34% reduction in relative risk, the researchers said (J. Amer. Coll. Cardiol. 2014 Aug. 18 [doi:10.1016/j.jacc.2014.05.060]).
The findings "refute any meaningful differences in clinical effectiveness as a function of race/ethnicity for either ICD or CRT-D (implantable cardioverter defibrillator with bradycardia pacing capabilities) therapy ... [and] reinforce current class 1 recommendations from the American College of Cardiology/American Heart Association HF guidelines that selected HF patients without racial/ethnic differentiation should, in the absence of specific evidence to treat otherwise, have clinical screening and therapy in a manner identical to that provided to the broader HF population," the researchers concluded.
The study was supported by Medtronic. Dr. Ziaeian and his associates reported ties to numerous industry sources.