Prediction of Graft Function from Hypothermic Machine Perfusion Parameters in Heart Transplantation from Donation after Circulatory Death

Purpose To investigate primary graft function of hearts from circulatory dead donors (DCD) preserved with oxygenated hypothermic machine perfusion (oHMP) (XVIVO Heart preservation system) following either direct procurement and perfusion (DPP) or normothermic regional perfusion (NRP) with subsequent transplantation and correlate graft function to oHMP perfusion parameters. Methods In a porcine model, DCD was instituted with circulatory arrest of 15 min, followed by preservation with either DPP and oHMP or NRP and oHMP. After 180 min preservation, orthotopic heart transplantation (HTX) was performed. Dobutamine and norepinephrine were titrated for inotropic and vasoconstrictive support. After weaning from cardiopulmonary bypass, ventricular function was assessed by pressure-volume admittance and Swan-Ganz catheters. Left ventricular contractility was correlated to available HMP parameters using spearman rank correlation. Results Functional warm ischemic time (FWIT) was similar between groups (DPP 19±1 and NRP 18±1 min, p = 0.23), while time from withdrawal to oxygenated reperfusion was significantly longer in the DPP group (DPP 39±6 and NRP 21±1 min, p < 0.001). End-oHMP coronary flow was negatively correlated to contractile function, while oxygen uptake was positive correlated contractile function. Delta values of perfusion parameters did not correlate to contractile function. Conclusion Coronary flow and oxygen extraction during oHMP may be important predictors of early graft contractile function post-HTX from DCD donors.