Machine perfusion compared to cold storage for preservation of hearts from non-heart beating donors

PURPOSE: With respect to organ shortage, Non heart Beating Donors (NHBD) are an alternative source of graft for transplantation. In renal transplantation, machine perfusion (MP) has proven to be superior to cold storage (CS) in NHBD. Heart transplantation from NHBD is currently not performed because of the prolonged ischemia and risk of primary non-functioning. METHODS: 16 pigs were prospectively randomized in 2 groups of NHBD. After anoxia induced cardiac arrest, hearts were harvested and preserved for 4 hours. In the first group, organs were preserved in a classical CS solution. In the second group, hearts were preserved by hypothermic MP on a modified Heartport system (Organ Recovery System; Des Plaines; IL). After preservation, the hearts were reperfused on a Langen-dorff system during 1 Hour. Myocardial energy states (intracellular lactate, nucleotides and phosphocrea-tine/creatine ratio) were evaluated in myocardial biopsies taken respectively before cardiac arrest (1) and 4 hours after preservation (2). Hemodynamic performances (Maximum pressure, maximum dP/dt, minimum dP/dt) of the reperfused grafts were recorded with an intraventricular balloon connected to a pressure transducer. RESULTS: Hearts from the MP group showed significant less lactate accumulation (4 vs 12,4μmole/g; p=0,004), lower AMP/ATP ration (0,083 vs 0,69; p=0,049) and higher phosphocreatine/creatine ratio (33 vs 6; p=0,002). There were no differences between the 2 groups in hemodynamic data (all p=NS). CONCLUSION: compared to CS, MP allows better preservation of the energy states of the grafts in an in vitro model of pig NHBD. Whether this improves hemodynamic performances of the graft has further to be investigated