Early- and long-term comparison of the on- and off-pump bypass surgery in patients with left ventricular dysfunction.

Objective: The adverse effects of extracorporeal circulation increase the morbidity and mortality risk of coronary bypass surgery, especially in patients with left ventricular dysfunction. The purpose of this study was to provide a comparison of the early and long-term outcome between patient groups with left ventricular dysfunction (LVEF<40% or LVPS>or=15) operated with or without using cardiopulmonary bypass.

Methods: Fifty-one patients with left ventricular dysfunction, who were operated on between October 1992 and March 1994, were investigated retrospectively. They were divided into two groups: BH-group included 26 patients and cardiopulmonary bypass group had 25 patients. Mean age and risk factors were identical. All patients received one vessel bypass left internal mammary artery to left descending artery.

Results: There was no early mortality and perioperative myocardial infarction in either group. In the early postoperative period the need of cardiac support therapy was significantly higher in the cardiopulmonary-bypass group than in the beating heart-group: 32% versus 7.7% (p<0.05). The need for blood products (for fresh frozen plasma 3.63 +/- 2.15u versus 2.5 +/- 1.34u; p = 0.023; for packed red blood cells 1.8 +/- 0.75u versus 1.25 +/- 0.46u; p = 0.048), the extubation time (18.2 +/- 5.5 hours versus 15.3 +/- 3.8 hours; p = 0.03) and the hospital stay (10.64 +/- 3.2 days versus 7.92 +/- 2.25 days; p = 0.001) were higher in the cardiopulmonary bypass -group than in the beating heart-group. Actuarial survival for the beating heart-group was 92.3 +/- 5.2% at 6 years, and for the cardiopulmonary bypass group was 92 +/- 5.4% at 6 years (p = 0.67).

Conclusions: In spite of more than four times as many patients in the cardiopulmonary bypass group requiring inotropic support after surgery, survival and cardiac death rates were similar for both groups. Off-pump bypass surgery conserves the blood constituents. The benefits of both techniques to improve the left ventricular performance score and ejection fraction were similar, but postoperative extubation time, length of intensive care unit and hospital stay were reduced significantly in the beating heart group. With these good results of the beating heart coronary bypass surgery and considering its cost effectiveness, we concluded that coronary bypass on a beating heart can be an alternative to cardiopulmonary bypass technique in selective patient groups.