Postoperative Changes in the Electrocardiogram in Congenital Heart Disease

Electrocardiograms of 41 cases of coarctation and of 73 cases of patent ductus arteriosus were analyzed before and after surgical correction of the defect. The changes in the electrocardiogram which occurred after surgical repair of the coarctation were considered to be due to the diminished load on the left ventricle. In 65 of the cases of patent ductus arteriosus, electrocardiographic signs of left ventricular hypertrophy were recorded. Eight patients, seven of whom presented atypical murmurs, showed evidence of right ventricular or combined ventricular hypertrophy. Following ligation of the ductus, the electrocardiogram became normal in the majority of the cases.