Enhanced 24-hour in vitro heart preservation with adenosine and adenosine monophosphate.

Continuous hypothermic perfusion is an effective means of preserving ex vivo cardiac allografts. Using canine hearts, we assessed the ability of the high-energy phosphate precursors adenosine and adenosine monophosphate to enhance the protective effect of continuous hypothermic perfusion. Group 1 hearts (controls) were perfused for 24 hours with a modified Krebs-Henseleit solution. Group 2 hearts were perfused with control perfusate to which adenosine was added (20 mumol/L). Group 3 hearts were perfused with control perfusate with adenosine monophosphate (0.1 mmol/L). After perfusion heart weights increased similarly in all groups. Coronary vascular resistance increased during the preservation period in group 1 hearts, but decreased in groups 2 and 3 hearts. Developed pressures were 103 +/- 22 mm Hg in group 1, 163 +/- 27 mm Hg in group 2 (p less than 0.01), and 141 +/- 34 mm Hg (p less than 0.05) in group 3. The rate of pressure development in group 2 (2143 +/- 249 mm Hg) and group 3 (2059 +/- 395 mm Hg) hearts was significantly greater than in group 1 hearts (1434 +/- 363 mm Hg, p less than 0.01). Only group 3 myocardial adenosine triphosphate levels were significantly greater than controls (3.18 +/- 0.52 mumol/gm vs 2.12 +/- 0.74 mumol/gm, p less than 0.05) on completion of perfusion. Myocardial lactate levels at this time were significantly higher in group 1 hearts (7.48 +/- 3.96 mumol/gm) compared with groups 2 and 3 (0.34 +/- 0.58 mumol/gm and 1.50 +/- 0.91 mumol/gm, respectively, p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)