To investigate the incidence of appropriate cardioverter-defibrillator (CD) shocks and mortality in patients with heart failure treated with combined cardiac resynchronization plus CD therapy (CRT-CD) versus CD therapy.
Of 529 patients, mean age 71 years, with heart failure and a mean left ventricular ejection fraction of 29%, 209 (40%) were treated with CRT-CD and 320 (60%) with CD therapy. Mean follow-up for appropriate CD shocks and for mortality was 34 months.
Appropriate CD shocks occurred in 112 of 320 patients (35%) treated with CD therapy versus 52 of 209 patients (25%) treated with CRT-CD (p = 0.014). Mortality occurred in 50 of 320 patients (16%) treated with CD therapy versus 12 of 209 patients (6%) treated with CRT-CD (p = 0.0006). Using the variables age, gender, ejection fraction, smoking, hypertension, diabetes, dyslipidemia, ischemic etiology, and use of beta blockers, angiotensin-converting enzyme inhibitors (ACEI) or angiotensin receptor blockers (ARBs), amiodarone, sotalol, digoxin, and statins, stepwise Cox regression analysis showed that significant independent variables for appropriate CD shocks were statins (risk ratio = 0.35, p < 0.0001), smoking (risk ratio = 2.52, p < 0.0001), and digoxin (risk ratio = 1.92, p = 0.0001). Significant independent variables for mortality were use of CRT (risk ratio = 0.32, p = 0.0006), statins (risk ratio = 0.18, p < 0.0001), ACEI or ARBs (risk ratio = 0.10, p < 0.0001), hypertension (risk ratio = 24.15, p < 0.0001), diabetes (risk ratio = 2.54, p = 0.0005), and age (risk ratio = 1.06 for each 1 year increase, p < 0.0001).
Statins reduce and smoking and digoxin increase appropriate CD shocks. Use of CRT-CD, statins, and ACEI or ARBs reduce mortality, and hypertension, diabetes, and older age increase mortality.
Use of CRT-CD, statins, and ACEI or ARBs in patients with heart failure and low ejection fraction reduce mortality. In these patients, statins reduce and digoxin increases appropriate CD shocks.
Harit Desai, No Financial Disclosure Information; No Product/Research Disclosure Information