Abstract
The operative results and left ventricular function were compared in diabetic (29 cases) and non-diabetic subjects (63 cases) who had undergone aortocoronary (A-C) bypas surgery. The rate of patency of the A-C bypass graft was lower in the diabetic (80.2%) than in the non-diabetic group (92.0%). Mean graft flow measured during the surgery was 44 m//min in the diabetic group. This was significantly lower than that of the non-diabetic group (57 m//min). The number of coronary arteries with resistance of more than 100 mmHg/m//sec was significantly larger in the diabetic group than in the non-diabetic group. There was no significant difference in the ejection fraction and the end-diastolic pressure of the left ventricle before and after the surgery in either of the two, groups.
The heart rate and double product increased, significantly after the surgery in both groups, but the rate of increase was more pronounced among the diabetics. The ejection fraction of the left ventricle did not improve postoperatively in the diabetic group, whose ejection fraction was 60% or less. But it increased significantly after the surgery in the non-diabetic group. Fractional shortening was significantly increased after the surgery in the non-diabetic group, in whom aortocoronary bypass operation had been performed on the anterior descending branch of the left coronary artery and the patency of the graft had been ascertained by postoperative coronary angiography. But it did not improve significantly in the diabetic group.
Thus, it was concluded that the rate of patency of the graft and the grade of improvement of the left ventricular function were significantly worse in the diabetic than in the non-diabetic group.
As a result, it was considered that the A-C bypass operation in diabetic patients should be restricted to those with absolute indications.