Reoperative coronary bypass surgery: Effect of patent grafts and retrograde cardioplegia

Objective: To determine the effects of patent or diseased aorta-coronary by pass grafts and retrograde cardioplegia on mortality during reoperative cor onary bypass surgery. Methods: We conducted a retrospective review of prospectively gathered data , supplemented by systematic chart review, of all patients (n = 744) underg oing reoperative coronary bypass surgery at our institution between 1990 an d 1997, Independent predictors of survival were determined by stepwise logi stic regression analysis. Results: At least one patent or stenosed graft to the left anterior descend ing artery was present in 50% of patients, to the circumflex territory in 2 7% of patients, and to the right coronary artery territory in 33% of patien ts. The previous left anterior descending graft was a saphenous vein in 82% and a left internal thoracic artery in 18%, of patients. In-hospital morta lity occurred in 42 (5.6%) patients. Patent or diseased grafts of any coron ary artery territory did not significantly increase the risk of mortality. Retrograde cardioplegia use increased in more recent years, was more freque nt in patients with stenosed grafts, and was associated with improved survi val. Independent predictors of mortality were as follows (with odds ratios and 95% confidence intervals in parentheses): failure to use retrograde car dioplegia (odds ratio 2.81; 1.28-6.20), New York Heart Association class (o dds ratio 2.69; 1.25-5.81), peripheral vascular disease (odds ratio 2.60; 1 .25-5.41), and left ventricular grade (2.07; 1.31-3.27). Conclusions: In this series, patent or stenosed grafts were not associated with an increased risk of mortality during reoperative coronary bypass surg ery, possibly because of increased use of retrograde cardioplegia in this p atient group. We strongly recommend the routine use of retrograde cardiople gia during redo coronary bypass surgery.