[Membranous subvalvular aortic stenosis. Its detection by transthoracic and transesophageal 2-D Doppler...

Five patients (four males and one female, aged 29 to 75 years) with subaortic stenoses were examined by transthoracal and transoesophageal echocardiography, including two-dimensional Doppler echocardiography. In only one patient could the obstruction of the left ventricular outflow tract be definitively evaluated by transthoracal echocardiography, whereas by transoesophageal echocardiography the presence of a subaortic membrane could be demonstrated in all patients. The latter method thus proved to be reliable in evaluating the extent of obstruction.