Improved myocardial protection by creatine phosphate in cardioplegic solution. An in vivo study in the pig during normothermic ischemia.

The effect of creatine phosphate in potassium cardioplegia was studied in a pig heart model in vivo. Fifteen pigs divided into two groups were placed on cardiopulmonary bypass and subjected to 1 hour of cardioplegic arrest at normothermia. In group I (control), in which a potassium cardioplegic solution was used, only two out of eight animals could successfully be weaned from bypass. In group II, on the other hand, in which creatine phosphate (10 mmol/l) was added to the cardioplegic solution, six out of seven animals could be weaned from bypass and the heart performance assessed by volume loading. Group II also exhibited better maintenance of high-energy phosphates during ischemia, with significantly higher adenylate charge potential, than group I. In all animals weaned from bypass--two in group I and six in group II--the ventricular performance was decreased compared with that before induction of ischemia. The results indicate that creatine phosphate could be an effective constituent in potassium cardioplegia.