Surgical Outcomes of HeartMate2 to HeartMate3 Pump Exchange: A Single Center Experience

Abstract

Purpose Little data exist regarding the surgical complexity of Heartmate2 (HM2) to HeartMate3 (HM3) pump exchange for the indication of HM2 pump thrombosis. In this analysis, we compare the operative and post hospital course between HM2 to HM2 vs. HM2 to HM3 exchange for pump thrombosis in a small case series. Methods A single center cohort of HeartMate 2 patients (n=351) was evaluated for exchange data. Individual patients with an exchange for HM2 pump thrombosis (n=29) were included in the analysis (HM2 to HM2 n=24, HM2 to HM3 n=5). Peri-operative and immediate post-operative outcomes were compared with t tests, rank sum and fishers exact tests, where appropriate. Results Baseline characteristic of patients undergoing HM2 to HM2 exchange and HM2 to HM3 exchange were similar (Table). All patients undergoing HM2 to HM2 exchange underwent a subcostal approach. All patients with a HM2 to HM3 exchange underwent median sternotomy. HM2 to HM3 pump exchange had a longer median cardiopulmonary bypass time, a longer median ICU stay, longer median ventilator days, and overall length of stay than HM2 to HM2 pump exchange (Table). Six months after surgery, no patients who underwent HM2 to HM3 exchange had recurrent hemolysis, while 7/24 (29%) who underwent HM2 to HM2 exchange had recurrent hemolysis. Conclusion HM2 to HM3 pump exchange is feasible, however this operation is more complex and has a longer recovery time than HM2 to HM2 subcostal exchange. It will be important to consider minimally invasive strategies going forward to allow this exchange to be performed with less morbidity. A larger sample size will be required to analyze long term outcomes after HM2 to HM3 exchange.