Off-pump coronary surgery: Effect on early mortality and stroke

Abstract

Background: Avoiding cardiopulmonary bypass in coronary artery bypass grafting is thought to reduce early mortality and morbidity. Methods: We used our prospective database to compare all patients having off-pump coronary surgery (n = 389) with those having on-pump coronary surgery (n = 2412) between March 15, 1995, and November 1, 2000. Patients were grouped by age (years) in decades (>90, 80-89, 70-79, 60-69, <60 years). The Northern New England risk model was applied. Thirty-two independent variables were entered into a stepwise logistic regression analysis with the end points being surgical mortality and postoperative stroke. Results: Patients undergoing off-pump operations were older (70.9 ± 12 vs 68.1 ± 11 years; P < .001), and their Northern New England predicted risk was higher (11.9% ± 13% vs 9.2% ± 10%; P < .001). However, patients having on-pump bypass had significantly more bypass grafts constructed (3.3 ± 0.8 vs 1.9 ± 0.8; P < .001) and triple-vessel coronary artery disease (58% vs 28%; P < .001). There were no significant differences in postoperative mortality, stroke rate, complications, and length of stay between the groups. Logistic regression analysis did not show that cardiopulmonary bypass was a risk factor for either surgical mortality (odds ratio, 1.08; P = .83) or stroke (odds ratio, 1.59; P = .27). Conclusion: Off-pump coronary bypass did not reduce early mortality and morbidity. Early and late results should be compared in a prospective randomized study.