LEFT-VENTRICULAR CONTRACILITY AFTER HYPOTHERMIC PRESERVATION - PREDICTIVE VALUE OF P-31 - NUCLEAR-MAGNETIC-RESONANCE SPECTROSCOPY

Early graft failure accounts for a substantial portion of the mortalit y after heart transplantation. This factor underscores the need for th e development of reliable methods for predicting graft performance and thus ensuring optimal clinical outcome. The aim of this study was to describe the link between myocardial metabolism evaluated throughout p reservation with the use of phosphorus 31-nuclear magnetic resonance s pectroscopy and ventricular contractility after reperfusion. Thirteen pig hearts were excised and preserved from 3 to 12 hours with clinical techniques. During preservation the hearts underwent, phosphorus 31-n uclear magnetic resonance spectroscopy. After reperfusion, left ventri cular contractility was evaluated with an isolated heart model undergo ing isovolumetric contraction. Throughout storage, beta-adenosine trip hosphate remained stable and intracellular pH and phosphocreatine decr eased exponentially, whereas inorganic phosphate increased exponential ly. Intracellular pH, phosphocreatine, inorganic phosphates measured a t the onset of preservation, and intracellular pH and phosphocreatine measured at the end of preservation correlated significantly with the left ventricular contractility after reperfusion. We conclude that the metabolic state of myocardium at excision is especially important and that phosphorus 31-nuclear magnetic resonance evaluation of the heart during preservation appears to provide reliable indexes for predictin g subsequent ventricular contractility after reperfusion.