Idiopathic hypertrophic subaortic stenosis. I. Interventricular septum during the systolic contraction.
Biplane left ventricular cineangiographies in 4 patients with typical obstructive idiopathic hypertrophic subaortic stenosis (IHSS) and in control patients with normal left ventricles were analysed. In the protruding hypertrophic muscular interventricular septum of IHSS a markedly reduced shortening occurs in either direction during the systolic contraction. It does not bend towards the right ventricle. It is suggested that the septum of IHSS acts as a suspender during the systolic contraction, thereby accounting for the fast stroke volume ejection and the high ejection fraction of IHSS.
D000328:Adult; D001020:Aortic Stenosis, Subvalvular / Q000000981:diagnostic imaging / Q000503:physiopathology*; D002312:Cardiomyopathy, Hypertrophic / Q000503:physiopathology*; D002932:Cineangiography; D005260:Female; D006346:Heart Septum / Q000000981:diagnostic imaging / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction; D013318:Stroke Volume; D013599:Systole