Extracorporeal heart perfusion before heart transplantation: the heart in a box

Cold static storage is a time-tested and simple method of preserving hearts retrieved from optimal donors after brain death (DBD). The increasing gap between supply and demand for donor organs together with changing donor and recipient characteristics have led to renewed interest in the use of machine perfusion to increase both the quality and quantity of donor hearts for transplantation.

Two major approaches to machine perfusion of donor hearts have been investigated - hypothermic (HMP) and normothermic machine perfusion (NMP). Recent preclinical studies with HMP confirm that it provides superior donor heart preservation to cold static storage. HMP systems have been developed for human heart preservation but have yet to be tested clinically. In contrast, NMP has undergone extensive clinical evaluation in human heart transplantation, including optimal and higher risk DBD donors. In addition, NMP has enabled distant procurement and successful transplantation of hearts retrieved from human donation after circulatory death donors.

Initial clinical experience suggests that NMP of donor hearts retrieved from higher risk DBD and donation after circulatory death donors enables well tolerated ex-vivo reanimation, preservation, and assessment of these organs. In particular, this technology allows successful utilization of extended-criteria donor hearts that would otherwise be discarded.