This study was designed to test the hypothesis that asanguineous reperfusion with a standard
crystalloid cardioplegic solution results in improved myocardial salvage after a period of global
ischemia. Four groups of 6 dogs each were placed on
cardiopulmonary bypass. Control group A (work only) performed two hours of controlled work by contracting against a saline-filled left intraventricular balloon. Control group B (
ischemia only) underwent 45 minutes of global normothermic
ischemia before simple blood reperfusion while supported on bypass. Groups C and D were subjected to
ischemia and reperfusion as in group B, followed by controlled
work stress as in group A. Group D, however, received 500 mL of St. Thomas' Hospital
solution immediately before blood reperfusion. Morphological analysis showed no significant injury in groups A and B, whereas group C had 11.4% +/- 2.4%
necrosis of heart mass versus 2.5% +/- 1.1% in group D (p less than 0.001). Biochemical data from left ventricular biopsies showed no significant differences between groups B, C, and D. Functional analyses showed deterioration of diastolic compliance in group C (p less than 0.05), although a significant difference in systolic functional indexes could not be detected. Myocardial protection and salvage was improved by initial reperfusion with an asanguineous
cardioplegic solution versus reperfusion with blood alone.