[Myocardial protection with verapamil in open cardiac surgery--a clinical study for the optimal use]

To determine the optimal use of Verapamil as a myocardial protective agent during open heart surgery, patients were divided into 3 groups of 15 patients each of the same severity and operative difficulty. In group I, Verapamil was added to the blood cardioplegia in a concentration of 1 mg/L. In group II, 0.2 mg/kg of verapamil was added in the pump prime and in group III, in addition to the same amount of pump prime, an additional 0.1 mg/kg of Verapamil was added to the bypass circuit at 60 minutes after the start of bypass and continuous drip of 0.5 micrograms/kg/min for 24 hours after surgery. Only group III continued to maintain an effective concentration of verapamil, that was said in a range between 15 and 100 ng/ml in the serum during and after surgery. It is suggested from the present study that recommendable verapamil administration is as in group III with no severe arrhythmias, significantly less usage of catecholamines without mortality.