Left ventricular end-systolic wall stress to volume relationship before and after surgical closure of ventricular septal defect.

Left ventricular function was examined angiographically in 64 patients with ventricular septal defect and 13 postoperative patients with a preoperatively large shunt (postoperative group). The unoperated 64 patients were divided into three groups; small (left-to-right shunt ratio less than 35%), moderate (35%-50%), and large (greater than 50%). The control group consisted of 27 patients with Kawasaki disease. For assessing left ventricular function, left ventricular shape and the end-systolic wall stress to end-systolic volume index ratio, as well as left ventricular ejection fraction were examined. Left ventricular ejection fraction was higher in the small-shunt group (p less than 0.05) than in the control group, but normal in the other groups. Left ventricular end-diastolic shape was normal only in the small-shunt group and more spherical in the other groups. The large-shunt group alone manifested more spherical left ventricular end-systolic shape and lower end-systolic wall stress to end-systolic volume index (p less than 0.001). These findings suggest that the left ventricular dysfunction is present in patients with a left-to-right shunt larger than 50%, but this change was reversible in patients who underwent early repair of ventricular septal defect.