Redo sternotomy versus left ventricular assist device explant as risk factors for early mortality following heart transplantation.

Abstract

There is an increasing proportion of patients with a previous sternotomy (PS) or durable left ventricular assist device (LVAD) undergoing heart transplantation (HT). We hypothesized that patients with LVAD support at the time of HT have a lower risk than patients with PS and may have a comparable risk to patients with a virgin chest (VC). This is a single-centre retrospective cohort study of all adults who underwent primary single-organ HT between 2002 and 2017. Multivariable Cox regression analyses were performed to compare 30-day and 1-year mortality between transplanted patients with a VC (VC-HT), a PS (PS-HT) or an LVAD explant (LVAD-HT). Three hundred seventy-nine patients were analysed (VC-HT: 196, PS-HT: 94, LVAD-HT: 89). A larger proportion of patients in the LVAD-HT group were males (83%), had blood group O (52%), non-ischaemic aetiology (70%) and sensitization (67%). The PS-HT group had a higher frequency of patients with congenital heart disease (30%) and PSs compared to LVAD-HT patients (P < 0.001). PS-HT and LVAD-HT patients required a longer bypass time (P < 0.001) and showed a greater estimated blood loss (P < 0.001). Postoperatively, LVAD-HT required haemodialysis more frequently than the VC-HT group (P = 0.031). Multivariable analyses found that PS-HT patients had increased 30-day mortality compared to VC-HT [hazard ratio (HR) 2.63, 95% confidence interval (CI) 1.15-6.01; P = 0.022] while LVAD-HT did not (HR 2.17, 95% CI 0.96-4.93; P = 0.064). At 1-year, neither PS-HT nor LVAD-HT groups were significantly associated with increased mortality compared to VC-HT. Transplants in recipients with PS-HT demonstrated increased early mortality compared to VC-HT patients. Although LVAD explant is often technically challenging, this population demonstrated similar mortality compared to those VC-HT patients. The chronic and perioperative support provided by the LVAD may play a favourable role in early patient outcomes compared to other redo sternotomy patients.