Biochemical and Functional Effects of Creatine Phosphate in Cardioplegic Solution during Aortic Valve Surgery - a Clinical Study

During myocardial ischemia there is a drop in high-energy phosphates in the myocardium. Cold potassium cardioplegia decreases but does not altogether prevent this reduction. Supplementation of cardioplegic solutions with the high-energy compound creatine phosphate (10 mmol/L) compared to plain cardioplegic solutions was investigated in this study. Thirty patients scheduled for aortic valve replacement were included. The patients were randomized to group I (creatine phosphate) or group II (control). Postoperative hemodynamic evaluation revealed no significant differences between the groups. However, group I exhibited a tendency toward a better stroke-work index (135 +/- 18% vs. 102 +/- 5% recovery 15 minutes after bypass and 145 +/- 16% vs. 119 +/- 11% recovery 105 min after bypass). There were fewer patients in group I (5/15) needing inotropic support compared to group II (9/14). The myocardial content of ATP and creatine phosphate showed no significant differences during ischemia and reperfusion. It is concluded that the myocardial protection during ischemia was sufficient to prevent significant reductions of myocardial ATP and creatine phosphate irrespective of supplementation with CP.