Gender Differences in Clinical Outcomes after Left Ventricular Assist Device (LVAD) Implantation - Does Device Strategy Matter?

Abstract

Findings regarding outcomes after LVAD implantation in women and men are inconsistent, which may be due to combining data from patients differing in device strategy. The present analyses explored gender differences at baseline in medical and psychosocial patient characteristics and multiple clinical outcomes, stratified for patients bridged to transplantation (BTT) and those intended for destination therapy (DT). 8,461 patients in DT (20% women), and 11,189 patients in BTT (22% women), who received a primary continuous-flow LVAD between 6/2006 and 12/2017 and were registered with INTERMACS, were analyzed by device strategy and gender. Outcomes included death, transplant, device explant due to recovery, and device replacement due to complications. Associations of gender with time until each competing outcome were evaluated using cumulative incidence function and cause-specific Cox proportional hazard models, controlling for age, disease severity, hematological parameters, and psychosocial factors (e.g., marital status, social support, depression, history of alcohol abuse, and smoking). In both BTT and DT, women were younger, reported less substance abuse, were less likely to be white, married and working for an income, but more likely to be depressed than men. In BTT, men were more likely to be currently smoking, whereas in DT, women were more likely to be smoking. In DT, women were also more likely to be overweight. Regarding outcomes, during a mean follow up of 19 months, women had an increased rate of death compared to men in BTT [HR 1.11, 95% CI (1.00-1.23), p < .05], but not in DT [HR 1.01, 95% CI (0.91-1.12)]; women's rate of device replacement, however was increased only in DT [HR 1.19, 95% CI (1.03-1.39), p < .05]. Only in BTT had women a lower rate to be transplanted than men [HR 0.83, 95% CI (0.76-0.90), p < .001]. In both BTT and DT, women had higher rates for explant due to heart function recovery than men, even after controlling for medical and psychosocial covariates [DT: HR 1.79, 95% CI (1.27-2.56), p < .01; BTT: HR 1.33 95% CI (1.00-1.79), p < .05]. The results indicate that women and men differ in outcomes depending on intended device strategy. Thus, distinguishing between device strategies may help to understand gender differences in clinical outcomes after LVAD implantation.