[Effect of nicardipine cardioplegia on A-V conduction system in coronary bypass surgery]

The effect of diltiazem and nicardipine cardioplegia on A-V conduction system was analyzed in 75 patients undergoing coronary bypass operation. The dose of these drugs into the crystalloid cardioplegia was 10 micrograms/kg in nicardipine group (n = 29) and 100 micrograms/kg in diltiazem group (n = 46). Among these patients, there was no operative death and no patient required IABP after surgery and there was no difference on the post operative CK-MB level, on the cardiac index and on the pulmonary pressure between two groups. The number of patients who had complete A-V block after release of aortic cross clamping was significantly smaller in nicardipine group than in diltiazem group: 45.7% in diltiazem group vs. 6.9% in nicardipine group at 30 minutes and 21.7% vs. 6.9% at 60 minutes. We conclude that the suppressive effect on A-V conduction system was significantly lower in nicardipine cardioplegia than in diltiazem cardioplegia in the patients undergoing coronary bypass operation.