EFFECTS OF SHORT-TERM SUPPLEMENTATION WITH COENZYME-Q10 ON MYOCARDIALPROTECTION DURING CARDIAC OPERATIONS

Background. Coenzyme Q10 (CoQ10) is a naturally occurring vitamin-like substance that may have a beneficial role in ischemia-reperfusion inj ury. Coenzyme Q10 administered either as an additive to cardioplegia o r as long-term preoperative oral supplementation has been reported to ameliorate myocardial injury after cardiac operations. Methods. To det ermine whether short-term oral supplementation with large doses of CoQ 10 (600 mg in divided doses 12 hours before operation) was effective i n myocardial protection, 20 patients with well-preserved left ventricu lar function (ejection fraction greater than 0.50) undergoing elective coronary revascularization were enrolled in a prospective, double-bli nd, placebo-controlled, randomized trial. Serial concentrations of CoQ 10, myoglobin, creatine kinase MB fraction, and cardiac troponin T wer e measured preoperatively and 1, 6, 24, 72, and 120 hours postoperativ ely. Efficacy of myocardial protection was also assessed by clinical o utcome and serial changes in electrocardiographic indices. Results. Th e patient groups were similar with respect to preoperative and intraop erative characteristics. There was no significant difference in the pr eoperative plasma levels cif CoQ10. These levels fell significantly in both groups after operation, although the magnitude of the decrease w as less in the CoQ10-supplemented group (43% versus 60%). In both grou ps, there were significant postoperative increases in myoglobin, creat ine kinase MB fraction, and cardiac troponin T. The magnitude of incre ases in cardiac troponin T was greater in the CoQ10-supplemented group , reaching marginal overall statistical significance (p = 0.06). Concl usions. Short-term supplementation with large doses of CoQ10 does not lead to improved myocardial protection in patients undergoing coronary revascularization with well-preserved ventricular function and relati vely short ischemic times.