Adding defibrillator to CRT no benefit in dilated cardiomyopathy

(HealthDay)—For patients with heart failure with indications for cardiac resynchronization therapy (CRT), those with ischemic cardiomyopathy (ICM), but not those with nonischemic dilated cardiomyopathy (DCM), benefit from additional primary prevention implantable cardioverter-defibrillator therapy, according to a study published in the April 4 issue of the Journal of the American College of Cardiology.

Sérgio Barra, M.D., from Papworth Hospital NHS Foundation Trust in Cambridge, U.K., and colleagues conducted an observational study involving 5,307 consecutive patients with DCM or ICM, without history of sustained ventricular arrhythmias who underwent CRT implantation with or without a defibrillator (4,037 and 1,270 patients, respectively).

After a median follow-up period of 41.4 ± 29.0 months, the researchers found that patients with ICM had better survival when receiving CRT with a defibrillator versus those receiving CRT without a defibrillator (hazard ratio, 0.76; 95 percent confidence interval, 0.62 to 0.92; P = 0.005), while no such difference was seen for patients with DCM (hazard ratio, 0.92; 95 percent confidence interval, 0.73 to 1.16; P = 0.49). The excess mortality in patients who did not receive defibrillators versus recipients of defibrillators was associated with sudden cardiac death in 8.0 percent of those with ICM and 0.4 percent of those with DCM.

"Among patients with heart failure with indications for CRT, those with DCM may not benefit from additional primary prevention implantable cardioverter-defibrillator therapy, as opposed to those with ICM," the authors write.