[Operation for discrete subvalvular aortic stenosis].

33 patients with discrete subvalvular aortic stenosis, membranous in 14 cases, fibromuscular rige in 16 and tunnel in 3 were treated surgically in the past ten years. This spectrum of abnormalities can be differentiated by echocardiography and angiocardiography. Our policy is to excise the membrane or fibromuscular rige. When the outflow tract has remain narrow owing to concentric thickening of that portion of the septum and free wall proximal to aortic annulus, a septal myomectomy is indicated. Because the operation of subaortic stenosis is safe and effective, once the diagnosis is established, operation is a reasonable surgical treatment alternative. Operative mortality rate was 6%. Follow-up results of all survivors are satisfactory.