While cardiac transplantation remains the most effective therapy for end-stage heart failure, it continues to be plagued by a severe donor shortage. Many potentially suitable organs are not transplanted due to concerns of inadequate preservation with hypothermic static storage. Experimental and clinical studies suggest that machine perfusion preservation improves myocardial preservation. The purpose of this study is to test the hypothesis that a novel hypothermic machine perfusion preservation device maintains allograft oxidative metabolism, limits lactate accumulation, and more effectively preserves high energy phosphate stores compared to cold storage in a human model.