Impact of cardiac resynchronization therapy on clinical outcomes in patients with continuous-flow left ventricular assist devices

Background Implantable cardioverter-defibrillators (ICDs) can improve survival in left ventricular assist device (LVAD) recipients. However, the impact of cardiac resynchronization therapy (CRT-D) on outcomes in continuous-flow left ventricular assist device (CF-LVAD) patients is not known. We sought to determine if CRT-D improved clinical outcomes in CF-LVAD patients compared with ICDs alone. Methods and Results Sixty-one consecutive CF-LVAD patients with an ICD or CRT-D were evaluated. Impacts of CRT-D on mortality, all-cause hospitalization, and incidence of atrial (AA) and ventricular (VA) arrhythmias after LVAD implantation was compared with patients with ICD alone. Of the 61 LVAD patients, 31 (age 59.8 ± 16 years, 84% male) had CRT-D and 30 (age 57.2 ± 13 years, 74% male) had ICD. Before LVAD implantation, no significant differences were noted between the groups in demographic and clinical characteristics, LVAD indications, and incidence of AA and VA. Over 682 ± 45 days of LVAD support, 8 patients (25.8%) died in the CRT-D arm versus 5 (16.7%) in the ICD arm (P =.35). No differences were noted between the CRT-D and ICD groups in all-cause (96.8 vs 93.3%; P =.63) and HF (19.4 vs 26.7%; P =.78) hospitalizations, left ventricular (LV) end-diastolic diameter (6.4 ± 1.5 vs 6.2 ± 1.1 cm, P =.47), and incidence of AA (35.4% vs 33.3%; P =.80), VA (29% vs 26.6%; P =.86), and ICD shocks (22.6% vs 16.7%; P =.93). Beta-blocker and antiarrhythmic drug use after LVAD implantation was similar in both groups. Conclusions In patients with refractory HF who received CF-LVADs, CRT-D, compared with ICD, did not significantly improve mortality, all-cause hospitalization, LV dimensions, and incidence of AA and VA.