[Differential diagnosis of obstructions to left ventricular outflow (author's transl)].

A total of 127 patients with different forms of obstruction to left ventricular outflow are studied. There were eight cases with supravalvular aortic stenosis, 79 with valvular aortic stenosis, 25 with hypertrophic subaortic stenosis, and 15 with subvalvular aortic stenosis. Clinical findings and electrocardiographic, radiographic, and angiohemodynamic data corresponding to these groups are reported, as well as the differential characteristics for each category from a clinical, electrocardiographic and radiographic point of view. The presence of a typical face, asymmetrical carotid and brachial pulses, absence of aortic ejection click and little or no aortic button on the chest roentgenogram reveals a supravalvular aortic stenosis. Valvular aortic stenosis shows aortic ejection click, poststenotic dilation of the ascending aorta, electrocardiographic signs of left ventricular hypertrophy and associated aortic regurgitation. Hypertrophic subaortic stenosis is characterized by a typical arterial pulse, marked "a" wave in the jugular venous pulse, double apical impulse on palpation and appearance or modification of the systolic ejection sound with Valsalva's maneuver.