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

Avoiding cardiopulmonary bypass in coronary artery bypass grafting is thought to reduce early mortality and morbidity.

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.

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).

Off-pump coronary bypass did not reduce early mortality and morbidity. Early and late results should be compared in a prospective randomized study.