Risk factors for post-transplant low output syndrome

Abstract

Objectives: Due to a serious heart donor shortage, the criteria for acceptance for transplantation have been expanded. This study assesses donor-related factors associated with postoperative low output syndrome (LOS) and long-term survival of recipients. Methods: From 1999 to February 2011, 36 heart transplantations were performed at our institute, of which 28 donor hearts (78%) were considered to be marginal due to high inotropic requirement (n = 11), recent episode of cardiac arrest (n = 11), female to male transplantation (n = 11), reduced left ventricular contraction (n = 6), old age (n = 6), small donor heart (n = 5), donor-recipient size mismatch (n = 2), ventricular hypertrophy (n = 2) or prolonged ischaemic time (n = 1). St Thomas solution (n = 6) and Celsior (n = 30) were used for preservation. Ischaemic damage in post-transplant cardiac patients was graded by perioperative ischaemic myocardial injury (PIMI) score (scores 0-3). Results: The donor age was 39 ± 11 years old, which was not significantly different to that of the recipients. 50% of the donors were female. Thirty-three donors (92%) required catecholamine at an average of 8.0 ± 5.2 μg/hg/min and echocardiogram findings showed that left ventricular ejection fraction was 65 ± 10%. All recipients survived during the perioperative period (one patient died from sepsis at 4 years after transplantation) for a 10-year survival rate of 95%. Severe primary graft dysfunction was observed in two patients who required intra-aortic balloon pumping or veno-arterial extra-corporeal membrane oxygenation, and five other patients showed postoperative LOS (cardiac index < 2.2 l/min/m2). Left ventricular diastolic diameter smaller than 36 mm (P = 0.0002), high inotropic requirement (P = 0.0089) and left ventricular ejection fraction less than 55% (P = 0.0383) were related to post-transplant LOS. All patients recovered cardiac function and were discharged from the intensive care unit after an average of 6 days. Although preservation with Celsior was not related to LOS, it had relationships with lower CKMB level (P = 0.0013) and lower PIMI score (P = 0.0054). Conclusions: Cautious donor selection is essential when the donor heart has a small ventricular diameter or requires a high level of inotropic support. However, long-term survival in recipients with marginal donor hearts can be anticipated with adequate treatment. © The Author 2012. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.