Impact of deactivated CRT on ventricular arrhythmia occurrence and survival in LVAD patients

Abstract Background The majority of LVAD patients with an active CRT device are CRT non-responders. Currently, there is no convincing evidence of any clinical benefit from continuing CRT therapy in patients on LVAD support. Objectives This study aimed to evaluate the impact of deactivating CRT therapy in patients with LVAD support on the incidence of ventricular arrhythmias, as well as on transplant-free survival and overall survival. Methods We conducted a retrospective cohort study of 178 patients with active CRT devices who underwent LVAD implantation at our Heart Center between September 2011 and December 2023. Results A total of 158 LVAD patients with an active CRT were included in our study. We excluded patients who received a heart transplant or died during the index hospitalization, in addition to those with CRT duration of less than one month after LVAD implantation. The patients were predominantly male (89%), had NICM (64%), and were on average 63±8 years old. All LVADs were continuous-flow devices (72 HVAD, 8 HeartMate II, and 78 HeartMate 3). In 48 patients (30%) CRT was turned off during the LVAD support for various reasons, most commonly due to LV lead dysfunction. The median time from LVAD implantation to CRT deactivation was 18.5 months. The incidence of ventricular arrhythmias (including both MVT and VF) within the first year after LVAD implantation was comparable between the CRT-on and CRT-off groups (37% vs. 40%, p=0.649). In both univariate (p=0.018) and multivariate analyses, CRT deactivation was associated with improved transplant-free survival (p=0.020, adjusted for sex, age, and underlying cardiomyopathy). The estimated 3-year transplant-free survival was 49% (95% CI: 40–58%) in the CRT-on group and 81% (95% CI: 70–92%) in the CRT-off group. No significant differences in overall survival were observed between the two groups. Conclusions Deactivation of LV lead pacing in LVAD patients with CRT had no impact on the incidence of ventricular tachyarrhythmias and may be associated with improved transplant-free survival.