During the first three years of grant support, from August, 1991 to November, 1995, clinical research was conducted on a comparison of intraoperative high versus low mean arterial pressure (MAP) on outcomes after coronary artery bypass. In this study, 248 patients undergoing primary, nonemergency coronary bypass were randomized to either low (n = 124) or high (n = 124) mean arterial pressure during cardiopulmonary bypass. The impact of the mean arterial pressure strategies on the following outcomes was assessed: mortality, cardiac morbidity, neurologic morbidity, cognitive deterioration, and changes in quality of life. All patients were observed prospectively to six months after the operation. Results are described under the Results Section.