The rate of regression of ventricular hypertrophy in vectorcardiogram and electrocardiogram after surgery on congenital heart disease

Summary Scalar electrocardiograms and vectorcardiograms were performed on children with isolated congenital heart defects just before corrective surgery, 7 to 10 days after surgery, and 6 to 18 months later. The early and late changes were statistically analyzed. In 36 cases of pulmonary stenosis there was a reduction of right ventricular hypertrophy in early and late cardiograms. In 42 cases of secundum atrial defect no significant reduction of right ventricular hypertrophy was shown in the early cardiograms, although the late cardiograms did show this effect; voltages from the left ventricle were significantly increased in both the early and late cardiograms. In 49 cases of patent ductus arterious left ventricular hypertrophy was reduced in the early and late cardiograms. In 39 cases of valvular aortic stenosis a reduction of the S in V 1 was seen in the early ECG and there was a significant reduction of left ventricular hypertrophy in the late cardiograms. The very rapid reduction of hypertrophy was surprising and may be explained by electrical phenomena or atrophy of the ventricle