Differentiating discrete subaortic stenosis (DSAS) from aortic valve stenosis (AVS) may be difficult, even at cardiac catheterization. Twenty-two patients with DSAS were studied echocardiographically and compared with 41 patients with AVS and 234 normal subjects. A ratio of left ventricular outflow tract to aortic root (LVOT: AO) < 0.80 determined LVOT narrowing in 19 of 22 DSAS patients. The a...

The discrete form of subaortic stenosis is thought to be an acquired lesion, the aetiology of which may be a combination of factors which include an underlying genetic predisposition, turbulence in the left ventricular outflow tract, and various geometric and anatomical variations of the left ventricular outflow tract. A review of hypotheses relating to its aetiology is provided

The mechanism of the apparent early closure of the aortic valve in patients with discrete membranous subaortic stenosis was studied. Discrete membranous subaortic stenosis was simulated in vitro to assess the fluid dynamic characteristics in the region of the aortic valve that may be responsible for the early closure. In the presence of a simulated fixed membranous subaortic obstruction, early ...