A Cardioprotective Perfusion Protocol Limits Myocardial Functional Decline During Ex Situ Heart Perfusion

Background: Ex situ heart perfusion is associated with a significant decline in graft quality related to oxidative stress, inflammation, endothelial dysfunction, and metabolic perturbations. We assessed the effects of a more optimized, cardioprotective normothermic perfusion approach compared to a conventional perfusion protocol in a slaughterhouse model using porcine hearts. Methods: A total of 12 hearts were harvested and subjected to 4 hours of normothermic perfusion. The optimized protocol consisted of an adenosine-lidocaine cardioplegic solution, subnormothermic initial reperfusion and controlled rewarming, hemofiltration and supplementation of methylprednisolone and pyruvate. This was compared to a conventional protocol consisting of St. Thomas II cardioplegic solution, normothermic initial reperfusion without hemofiltration or methylprednisolone, and a mixture of glucose and insulin for metabolic support. Results: Myocardial function was superior in the optimized group, while significant functional decline was absent. Hearts subjected to the conventional protocol demonstrated a significant reduction in function over time. Conclusions: We have developed a further optimized, cardioprotective normothermic ex situ heart perfusion approach and demonstrated significantly improved myocardial function and attenuated functional decline during 4 hours of normothermic perfusion, indicating improved preservation.