Outcomes of Mechanical Circulatory Support Therapy for Cardiogenic Shock Associated with Late Allograft Failure after Heart Transplantation

Abstract

Treatment of cardiogenic shock associated with late allograft failure after heart transplant (HT) is poorly characterized and infrequently reported. In this study, we examined the role of mechanical circulatory support (MCS) as a method to treat patients with severe late graft failure. From 2000 - 2018, there were 1275 adult HT at our institution. Of those, 26 patients (2.0%) were identified who required MCS for cardiogenic shock due to late allograft failure. Patient demographics and outcomes were retrospectively reviewed. Median age of the cohort was 37.3 years (IQR: 17.3) and 69% were male. Median time from initial transplant to MCS was 2.9 years. At the time of shock, median hemodynamic values were as follows: CVP 18 mmHg, mean PA pressure 29 mmHg, PCWP 25 mmHg, and CI 1.87 L/min/m2. On echocardiogram, median LVEF was 25% and 77% of patients had moderate or severe right ventricular dysfunction. Seven patients (27%) had severe allograft coronary disease, while all remaining patients had chronic or acute worsening rejection. Initial MCS used included veno-arterial extracorporeal membrane oxygenation in 15 patients (58%), biventricular assist device in 10 patients (38%), and total artificial heart in 1 patient (4%). 8 patients underwent revision of MCS during the same hospitalization, on average 18 days after initial placement. While on MCS, the most common treatments for rejection were pulse dose steroids (69%), thymoglobulin (54%), and plasmapheresis (31%), with nearly all patients receiving combination therapy. Six patients (23%) weaned from MCS following medical therapy. Median duration of MCS was 33 days (IQR 55). Major morbidities included bleeding events in 39%, new renal replacement therapy in 23%, major infection in 27%, and stroke in 23%. Eight patients (31%) underwent re-heart transplant, all within one year of MCS, and survival for this cohort was 100% at 1 year. However, for those patients who were not offered re-transplant or who died while awaiting re-transplant, 1 year survival was only 22%, with 61% of deaths occurring in the hospital. Late graft failure resulting in cardiogenic shock carries significant morbidity and mortality, despite use of contemporary MCS.