Impact of cardiac resynchronization therapy-defibrillator implantation on the association between body mass index and prognosis in patients with heart failure.

Abstract

This study aimed to examine the association between body mass index (BMI) and prognosis in heart failure patients after cardiac resynchronization therapy-defibrillator (CRT-D) implantation. We retrospectively investigated 125 patients (33 overweight [BMI ≥25 kg/m(2)], 75 normal weight [BMI 18.5-24.9 kg/m(2)], and 17 underweight patients [BMI <18.5 kg/m(2)]) who underwent CRT-D implantation. The clinical outcome endpoints were all-cause death and appropriate shock therapy. During the follow-up period (mean 3.1 ± 1.8 years), 23 patients died (1 [3.0 %] overweight, 17 [22.7 %] normal weight, and 5 [29.4 %] underweight patients), and appropriate shock events were observed in 14 patients (2 [6.1 %] overweight, 10 [13.3 %] normal weight, and 2 [11.8 %] underweight patients). All patients survived shock therapy. After adjusting for confounding factors, overweight patients had significantly fewer outcomes relating to all-cause death and appropriate shock events (hazard ratio 0.27, 95 % confidence interval 0.08-0.91, p = 0.034) than normal weight patients. However, the prognostic difference between overweight and normal weight patients could be diminished as a result of the successful shock therapies (p = 0.067). Additionally, prognosis did not differ between overweight and normal weight patients among the responders, but did differ among the non-responders. The underweight patients had a poorer prognosis after CRT-D implantation compared with the other groups. Although high BMI was associated with better outcomes among heart failure patients with CRT-D implantations, the difference in the prognosis between overweight and normal weight patients was reduced because of defibrillator therapy and the improvement in cardiac function provided by CRT-D implantation.