LEFT HEART VOLUME CHARACTERISTICS FOLLOWING VENTRICULAR SEPTAL-DEFECT CLOSURE IN INFANCY

Left ventricular and left atrial volume, left ventricular ejection fraction, and left ventricular muscle mass were determined preoperatively and postoperatively in 13 patients who underwent surgical closure of ventricular septal defects in the 1st 2 yr of life. Left ventricular end-diastolic volume and systolic output averaged 255 .+-. 19% (.+-. SEM [standard error of the mean]) and 240 .+-. 19% of normal, respectively, before operation but fell to within normal limits postoperatively. Left ventricular ejection fraction was normal preoperatively (100 .+-. 4% of normal) and remained so after correction (106 .+-. 3%, NS [not significant]). Left ventricular mass was mildly elevated at the preoperative catheterization (271 .+-. 21%) and decreased significantly following repair (P < 0.001). The postoperative left atrial volume (147 .+-. 14%) remained abnormal (P > 0.05). When early surgical closure of a ventricular septal defect is necessary because of failure of medical management, good results with regard to postoperative left ventricular size and function can be expected.