The benefit of cardiac resynchronization therapy with a defibrillator (CRT-D) relative to implantable cardioverter-defibrillator (ICD) therapy alone has not been evaluated in routine clinical practice.\u00a0 This study used data from the National Cardiovascular Data Registry’s ICD Registry linked with Medicare claims data to compare outcomes after CRT-D and ICD implantation in community practice.\u00a0 The analysis included 7090 propensity matched patients who underwent either CRT-D or ICD implantation between 2006 and 2009 at one of 780 U.S. hospitals participating in the NCDR ICD registry.\u00a0 Patients were over age 65 and met criteria for CRT-D implantation (left ventricular ejection fraction \u2264 35% and QRS duration \u2265 120ms). Over 3 years of follow-up, CRT-D was associated with lower risk of mortality (HR 0.82, 99% CI 0.73-0.93), all-cause readmission (HR 0.86, 99% CI 0.81-0.93), and heart failure readmission (HR 0.78, 99% CI 0.69-0.88) compared with ICD therapy.\u00a0 However, CRT-D was also associated with a higher risk of device related infection (HR 1.90, 99% CI 1.07\u20133.37).\u00a0 In subgroup analyses, the reduced risk of heart failure readmission was most prominent among patients with left bundle branch block or QRS duration of at least 150 ms.<\/p>\n
\u00a0Conclusions<\/strong><\/p>\n In routine clinical practice, patients who were eligible for CRT-D therapy according to criteria based on the findings of clinical trials experienced better long-term outcomes than patients treated with ICD alone. \u00a0These findings suggest the benefits observed in highly controlled clinical trials of CRT-D have translated into patient benefit in for properly selected patients in routine clinical practice<\/p>\n