Comparison of LVAD as BTT with Direct Heart Transplantation

Abstract

<h3>Purpose</h3> Left ventricular assist devices (LVAD) are often used to support end-stage heart failure and as a bridge-to-transplant therapy (BTT) to heart transplantation (HTx). We compared survival outcomes of continuous-flow LVAD (CF-LVAD) used BTT versus HTx patients. <h3>Methods</h3> Adult HTx and BTT patients were extracted from UNOS database (2005-2020) for analysis. CF-LVADs were implanted at and during the time of listing. Descriptive analysis (Chi-square and Mann-Whitney U testing) were performed using variables such as age, gender, ethnicity, blood groups, ventilator and ECMO usage, ventilator time, and length of stay (LOS). A Kaplan-Meier (K-M) curve compared the survival outcomes, which were analyzed by the log-rank test. Data were expressed as mean ± standard deviation using SPSS 25.0 inc. A p<0.05 value was considered significant. <h3>Results</h3> Out of 76,482 total HTx patients, adult BTT and HTx patients (n=33,297) were analyzed. 9,420 received CF-LVAD whereas n=23,877 underwent direct HTx. Data for both groups showed 74% male, 66% white, 21% black, 8% Hispanic, 3% Asian, and 2% other; mean age 53 ± 12 years; mean LOS 21 ± 25 days; blood groups O-39%, A-40%, B-15%, AB-6%; ECMO usage 1.2%; and ventilator usage 1.7%. 35% received ventilator at the time of transplant (Tx), 26% received ventilator within 3 months of Tx, and 39% received ventilator more than 3 months prior to Tx. When compared between groups, there were significant differences in age (p<0.001), gender (p<0.001), ethnicity (p<0.001), blood groups (p<0.001), ventilator time (p<0.001), ECMO usage (p<0.001), and LOS (p<0.001) and no statistical significance in ventilator usage (p=0.08). K-M graph showed 90% overall survival at 1-year (p=0.150), 86% survival at 3-years (p=0.221), 82% survival at 5-years (p=0.084), and 76% survival at 10-years (p=0.380). <h3>Conclusion</h3> The 10-year analysis period showed no statistical significance in survival differences between HTx patients with and without LVAD. All other variables except ventilator usage had significant differences in the two groups.