Impact of sex on the burden of sustained ventricular tachyarrhythmic events following LVAD implant: preliminary data from the PIVATAL Trial

Introduction Prior data suggest that there are sex-differences in the risk of ventricular tachyarrhythmias (VTA) in patients with heart failure with reduced ejection fraction (HFrEF). However, limited data exist on the risk of VTA in high-risk males and females with advanced HFrEF who undergo left ventricular assist device (LVAD) implant. In this study we aimed to compare possible sex-differences in clinical and arrhythmic outcomes between men and women patients who were enrolled in the PIVATAL trial. Methods The PIVATAL trial is an ongoing prospective, multi-center randomized trial designed to evaluate the outcome of intra-operative VTA ablation vs. medical management in 100 high risk patients with history of sustained VTA while undergoing LVAD implant. In this interim blinded analysis, we compared the clinical characteristics, VTA incidence and mortality following LVAD implant in men and women patients based on independently adjudicated VTA and clinical outcome data on the first 89 patients enrolled in the trial. Results Overall mean age was 59±11 years, 26% were women and average INTERMACS score was 3.4. The average LVEF was 17±5%. Of the 89 patients enrolled to date, 48 underwent intra-operative VT ablation. Male patients were older (60 vs. 54 years) and had a higher rate of renal dysfunction and hypertension (Table 1). At 15 months of follow-up, the cumulative incidence of first VT/VF (treated or monitored), after accounting for the competing risk of death, was the same in male patients (42%) vs. female (42%), with high early recurrence rates of 34% and 36% at 6 months, respectively (p = 0.57 for the overall difference during follow-up; Figure 1A). Mortality was non-significantly higher in men (28% vs. 12% at 15 months, p = 0.32 (Figure 1B). The rate of peri-LVAD implant complications was similar between males and females and none of the complications was related to the intra-operative ablation procedure. Conclusion In this interim analysis of the PIVATAL trial, women experienced similarly high rates of recurrent VT/VF and mortality to men following LVAD implant, despite presenting with generally lower-risk baseline clinical characteristics. These findings suggest that advanced substrate-related arrhythmogenic risk in advanced HFrEF may outweigh sex-specific predispositions in this high-risk population. Final PIVATAL analyses will further assess response to intra-operative VT ablation by sex.