Ventricular Assist Device Utilization in Heart Transplant Candidates: Nationwide Variability and Impact on Waitlist Outcomes

Background: Continuous-flow left ventricular assist devices (CF-LVADs) have become a standard treatment choice in advanced heart failure patients. We hypothesized that practice patterns with regards to CF-LVAD utilization vary significantly among transplant centers and impact waitlist outcomes. Methods and Results: The United Network for Organ Sharing registry was queried to identify adult patients who were waitlisted for heart transplantation (HT) between 2008 and 2015. Each patient was assigned a propensity score based on likelihood of receiving a durable CF-LVAD before or while waitlisted. The primary outcomes of interest were death or delisting for worsening status and HT at 1 year. A total of 22 863 patients from 92 centers were identified. Among these, 9013 (39.4%) were mechanically supported. CF-LVAD utilization varied significantly between and within United Network for Organ Sharing regions. Freedom from waitlist death or delisting was significantly lower in propensity-score-matched patients who were mechanically supported versus medically managed (83.5% versus 79.2%; P<0.001). However, cumulative incidence of HT was also lower in mechanically supported patients (53.3% versus 63.6%; P<0.001). Congruous mechanical and medical bridging strategies based on clinical risk profile were associated with lower risk of death or delisting (hazard ratio, 0.88; P=0.027) and higher likelihood of HT (hazard ratio, 1.14; P<0.001). Conclusions: CF-LVAD utilization may lower waitlist mortality at the expense of lower likelihood of HT. Decision to use CF-LVAD and timing of transition should be individualized based on patient-, center-, and region-level risk factors to achieve optimal outcomes.