Bridge to transplant in the contemporary allocation era: a systematic review and meta-analysis of impella versus intra-aortic balloon pump
M V Montenegro, P G Batista, R R A Santos Silva, M Malik, L A Lucena, G C Gaelzer, M E Molinari, J Peres de Oliveira, R Huntermann, M Dandamudi, C Fischer Bacca, J GiorgiAbstract
Background
Temporary mechanical circulatory support (tMCS) is frequently required to stabilise advanced heart failure patients (AHF) awaiting heart transplantation (HTx) under Status 2 criteria. Contemporary practice has shifted towards greater use of surgically implanted microaxial pumps (Impella CP, 5.0, or 5.5) compared with intra-aortic balloon pump (IABP), yet comparative post-transplant outcomes remain uncertain.
Purpose
This study aimed to compare post-transplant outcomes in patients with AHF awaiting heart transplantation who received either Impella microaxial pumps or IABP as temporary mechanical circulatory support until the transplant.
Methods
PubMed, Embase, and Cochrane were systematically searched. We included studies comparing Impella versus IABP as a bridge-to-transplant in adult Status 2 candidates and pooled effect estimates using random-effects models. Across the provided eligible studies, 15,872 transplanted recipients were analysed.
Results
Compared with IABP, Impella support was associated with similar 1-year mortality (RR 0.49 [95% CI 0.05–4.66], P=0.53), short-term mortality (RR 1.66 [95% CI 0.46–5.94], P=0.4344), acute rejection (RR 1.23 [95% CI 0.65–2.32], P=0.52), first graft dysfunction (RR 1.08 [95% CI 0.70–1.66], P=0.73), dialysis post-transplant (RR 0.91 [95% CI 0.73–1.13], P=0.40), length of hospital stay (MD −0.05 days [95% CI −1.92 to 1.82], P=0.95), and bleeding at insertion (RR 2.84 [95% CI 0.61–13.20], P=0.16), with lower chronic rejection (RR 0.95 [95% CI 0.91–1.00], P=0.03) but higher post-transplant stroke risk (RR 1.64 [95% CI 1.18–2.28], P=0.003); Impella use was also associated with longer duration of mechanical circulatory support (MD 9.31 days [95% CI 2.34–16.27], P=0.008), greater need for mechanical ventilation at transplantation (RR 1.31 [95% CI 1.04–1.65], P=0.01), and nonsignificant trends towards longer waiting list time (MD 2.20 days [95% CI −0.07 to 4.47], P=0.05) and higher inotrope use at transplant (RR 1.09 [95% CI 0.98–1.21], P=0.09).
Conclusions
Compared with IABP, Impella support showed no clear mortality or graft-survival advantage and was associated with greater peri-transplant support requirements and higher post-transplant stroke risk.Grafical Abstract