Patients were randomly assigned to cold, tepid, or warm blood cardioplegia, coinciding with normothermic, tepid, and hypothermic cardiopulmonary bypass. All patients received a standard anesthetic protocol combining narcotic and inhalational anesthesia. Each patient entering the study had extensive clinical data collected prospectively incorporating most aspects of measurable determinants related to myocardial preservation. Additionally, neurologic tests were performed by a blinded neurologist and rated by an objective scoring system, the Mathew scale. The studies were performed preoperatively, on the third or fourth postoperative day, and at one month following surgery. Hematologic data were measured for fibrinolytic potential.