Reperfusion injury remains a limiting factor in extending ischemic storage time for human heart transplantation. In this study, initial myocardial reperfusion with an oxygenated perfluorochemical (Fluosol) was investigated as a means of limiting such injury. Neonatal piglet hearts were arrested with crystalloid cardioplegia, excised, and stored for 12 hours in saline solution at 0 degrees C. Initial reperfusion (10 minutes) was either with whole blood (n = 6), unmodified perfluorochemical (n = 8), or aspartate/glutamate-enriched perfluorochemical cardioplegia (n = 6), and was followed by an additional 40 minutes of whole blood perfusion. Functional evaluation was then completed, and left ventricular biopsy specimens were taken. A control group (n = 7) was evaluated without an intervening period of ischemia. At a left ventricular end-diastolic pressure of 9 mm Hg, hearts stored in whole blood cardioplegia developed a left-ventricular stroke work index of 3.8 +/- 2.3 x 10(3) erg/g (mean +/- standard error of the mean). Under the same conditions, perfluorochemical-reperfused hearts achieved a stroke work index of 14.6 +/- 1.3 x 10(3) erg/g, significantly greater than that of the whole blood group (p < 0.001). Stroke work index for hearts reperfused with aspartate/glutamate-enriched perfluorochemical cardioplegia was 19.8 +/- 1.6 x 10(3) erg/g, significantly increased over that of the nonenriched perfluorochemical group (p < 0.01) and not different from values obtained in controls (19.2 +/- 0.8 x 10(3) erg/g).(ABSTRACT TRUNCATED AT 250 WORDS)