Incidence of appropriate cardioverter-defibrillator shocks and mortality in patients with implantable cardioverter-defibrillators with ischemic cardiomyopathy versus nonischemic cardiomyopathy at 33-month follow-up

INTRODUCTION The aim of the study was to investigate at long-term follow-up the incidence of appropriate implantable cardioverter-defibrillator (ICD) shocks and of all-cause mortality in patients with ICDs with ischemic cardiomyopathy versus nonischemic cardiomyopathy. MATERIAL AND METHODS ICDs were implanted in 485 patients with ischemic cardiomyopathy and in 299 patients with nonischemic cardiomyopathy, all of whom had coronary angiography. Baseline characteristics were not significantly different between the 2 groups. Follow-up was 965 days in patients with ischemic cardiomyopathy versus 1039 days in patients with nonischemic cardiomyopathy (p not significant). The ICDs were interrogated every 3 months to see if shocks occurred. RESULTS Appropriate ICD shocks occurred in 179 of 485 patients (37%) with ischemic cardiomyopathy and in 93 of 299 patients (31%) with nonischemic cardiomyopathy (p not significant). All-cause mortality occurred in 162 of 485 patients (33%) with ischemic cardiomyopathy and in 70 of 299 patients (23%) with nonischemic cardiomyopathy (p = 0.002). CONCLUSIONS The incidence of appropriate ICD shocks was not significantly different at 33-month follow-up in patients with ischemic cardiomyopathy versus nonischemic cardiomyopathy. However, patients with ischemic cardiomyopathy had a significantly higher incidence of all-cause mortality than patients with nonischemic cardiomyopathy (p = 0.002).