Improvement of left ventricular function after surgical correction of chronic aortic regurgitation.

Serial left ventricular (LV) echocardiographic studies were performed in 21 patients before and after aortic valve replacement for chronic aortic regurgitation. The effect of valve replacement on LV dimensions, cross-sectional area of the LV muscle and LV function was determined from the echocardiographic data. The relation between degeneration of the myocardium and surgical outcome was also investigated. The average LV end-diastolic dimension decreased from 66.0 +/- 8.3 mm to 46.3 +/- 5.7 mm twelve months postoperatively. The average LV end-systolic dimension also fell from 43.4 +/- 8.1 mm to 31.1 +/- 5.0 mm. The muscle cross-sectional area decreased from 33.1 +/- 5.1 cm2 to 24.5 +/- 4.0 cm2, indicating a decrease in LV mass. The indices of contractility (fractional shortening, ejection fraction and mean velocity of circumferential fibre shortening) had a tendency to decrease one month after surgery, but they subsequently increased to the normal level 12 months after surgery. Nineteen out of 21 patients showed a favorable outcome as to the functional status. The remaining two patients had a large LV dimension and subnormal contractility, and they failed to show a significant reduction in the follow-up period. The muscle score in the two patients was greater than 8 points, which indicated irreversible impairment of the myocardium. Patients with persistent postoperative LV enlargement have a poor prognosis and should be identified so that aggressive medical treatment can be instituted.