Risk factors among patients undergoing repeat aorta-coronary bypass procedures.

It is estimated that as many as 7% of patients who have an aorta-coronary bypass operation will require a second bypass procedure within 10 to 12 years. Using information from the Milwaukee Cardiovascular Data Registry, we matched 166 men who underwent two coronary bypass operations at least 6 months apart, between 1968 and 1981, with 428 patients who had a single procedure. Patients were matched according to date of operation and left ventricular wall motility function for analysis of risk factors for repeat operation. Elevated triglyceride levels were found to be the strongest risk factors associated with reoperation. In addition, both younger age and less complete revascularization during the first operation were significant predictive factors of repeat operation. The results suggest that efforts to reduce plasma triglyceride levels and ensure adequate revascularization may significantly reduce the need for repeat coronary bypass.