Influence of diabetes on cardiac resynchronization therapy with or without defibrillator in patients with advanced heart failure

Abstract

Objectives: We performed a post hoc analysis to determine the influence of cardiac resynchronization therapy with a defibrillator (CRT-D) or without a defibrillator (CRT-P) on outcomes among diabetic patients with advanced heart failure (HF).

Background: In patients with systolic HF, diabetes is an independent predictor of morbidity and mortality. No data are available on its impact on CRT-D or CRT-P in advanced HF.

Methods: The database of the Comparison of Medical Therapy, Pacing and Defibrillation in Heart Failure trial was examined to determine the influence of CRT (CRT-D and CRT-P) on outcomes among diabetic patients. All-cause mortality or hospitalization, all-cause mortality or cardiovascular hospitalization, all-cause mortality or HF hospitalization, and all-cause mortality were analyzed among diabetic patients (n = 622). A Cox proportional hazard model, adjusting for age, gender, New York Heart Association, ischemic status, body mass index, left ventricular ejection fraction, heart rate, QRS, left or right bundle branch block, blood pressure, comorbidities (renal failure, carotid artery disease, peripheral vascular disease, hypertension, coronary artery bypass grafting, and atrial fibrillation), medications, and device (with or without defibrillator), was used to estimate hazard ratios (HRs) and significance.

Results: The overall outcome of diabetic patients was similar to that of nondiabetic patients in the optimal pharmacologic therapy arm. With CRT, diabetic patients experienced a substantial reduction in all-cause mortality or all-cause hospitalization (HR = 0.77, 95% confidence interval [CI] 62-0.97), all-cause mortality or cardiovascular hospitalization (HR = 0.67, 95% CI 0.53-0.85), all-cause mortality or HF hospitalization (HR = 0.52, 95% CI 0.40-0.69), and all-cause mortality (HR = 0.67, 95% CI 0.45-0.99) compared with optimal pharmacologic therapy. Procedure-related complications and length of stay were identical in diabetic and nondiabetic patients.

Conclusion: In diabetic patients with advanced HF, there is a substantial benefit from device therapy with significant improvement in all end points.