What are the results of venoarterial extracorporeal membrane oxygenation bridging to heart transplantation?

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was whether heart transplantation is a viable treatment option in patients in refractory cardiogenic shock who could not be weaned off venoarterial extracorporeal membrane oxygenation (VA ECMO). Altogether, 373 papers were found using the reported search, of which 7 papers represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. Evidence is derived from 3 papers based on registry analysis, 1 multi-institutional study and 3 single-institution reviews. Early post-transplant mortality of ECMO-bridged recipients ranges from 18.7% to 33.3% and 1-year survival from 44.6% to 72.0%. High acuity of recipient illness reflected by poor renal function, mechanical ventilation, advanced age, elevated serum lactate predict inferior outcome. We conclude that heart transplantation results in patients bridged with VA ECMO are inferior when compared to published outcome of non-bridged recipients. In the era of severe organ shortage and intense public and regulatory scrutiny of the results, the decision to transplant a patient directly of VA ECMO needs to be made on a case-by-case basis. Potential gain in decreasing the waiting list mortality of these critically ill patients needs to be weighed against poorer post-transplantation mortality rates and mid- and long-term outcomes.