Early Outcomes of Direct Heart Transplant Off Veno-Arterial Extracorporeal Membrane Oxygenation Support after New Heart Allocation Policy: Analysis Based on Etiology of Cardiomyopathy

Purpose The new heart allocation policy from October 2018 prioritizes patients on venoarterial extracorporeal membrane oxygenation (VA-ECMO) at the highest listing status, which may influence treatment strategies in acute cardiogenic shock. The aim of this study is to evaluate the outcomes of direct orthotopic heart transplant (OHT) from VA-ECMO at our institute after the allocation change. Methods From October 2018 to September 2020, 56 adult patients received OHT at our center. Of these, 10 patients (17.9%) underwent OHT from VA-ECMO. The outcomes of these patients were compared between myocardial infarction (MI) (N=5) and Non-MI patients (N=5). Results Patients in the MI group were significantly older than the non-MI group (59.8+/-11.1 vs 32.6+/-7.9 years-old, P=0.016). Eight patients were blood type A and 2 patients were blood type O. Pre-ECMO cardiopulmonary resuscitation was performed in 2 patients (40%) in the MI group and 3 patients (60%) in the Non-MI group. The length of VA-ECMO support before transplant was 5.8+/-4.1 days in MI group, and 3.0+/-1.9 days in Non-MI group (P=0.222). Mean ischemic time of a donor heart (MI: 173.8 +/- 65 min vs. Non-MI: 179.2+/-65 min, P=0.548) was comparable. There was no hospital mortality in either group. VA-ECMO support was continued in 80% of patients in MI group, and 20% in Non-MI group (P=0.206) post-OHT. Temporary hemodialysis was required in 3 patients in MI group (60%) and none in Non-MI group (P=0.168). Tracheostomy was performed in 2 patients in MI group who were decannulated before discharge. There was one mortality in MI group (63 year-old, post-cardiotomy patient) 8 months after transplant due to renal failure and infection. Conclusion Compared to Non-MI patients, MI patients bridged to OHT from VA-ECMO were older, frequently required continuation of mechanical support, and had more adverse events such as renal failure or respiratory failure. Although further experience and follow-up is necessary, our series of direct OHT off VA-ECMO after new allocation policy showed favorable overall outcomes, especially in patients on VA-ECMO support without shock from MI.