Late results after resection of fixed subaortic stenosis.

Resection of fixed subaortic stenosis was performed on 44 patients with median age 14 (range 2-61) years. Concomitant aortic valve pathology was present in 14 (32%) cases (congenital stenosis in 2, thick fibrotic cusps in 8 and incompetent cusps in 4) and other congenital cardiovascular malformations in eight (18%). There was no perioperative mortality. Of the six late deaths, three were due to non-cardiac causes. During follow-up (median 6, range 2-21 years), six reoperations were performed for residual or recurrent obstruction and/or aortic incompetence. Aortic valve replacement was required at two primary and four second operations. Actuarial 5-year and 10-year survival rates were 89% and 76%, respectively, and rates with freedom from cardiac death endocarditis and reoperation 83% and 64%. At follow-up evaluation two patients had significant aortic regurgitation and all survivors had a systolic ejection murmur. At Doppler echocardiography in 29 patients without reoperation, the median pressure difference in the left ventricular outflow tract was 10 (range 0-55) mmHg--in three cases greater than or equal to 30 mmHg. Careful follow-up is advisable after resection of fixed subaortic stenosis, because of the risk of residual or recurrent obstruction and of significant aortic valve incompetence.