Idiopathic hypertrophic subaortic stenosis. IV

The ventricular volumes and the myocardial fibre length have been analysed frame by frame from cine angiography of the left ventricle at 75 frames per second through the diastolic period in 4 patients with idiopathic hypertrophic subaortic stenosis (IHSS) and 10 control patients. The fibre length was analysed by means of geometric models previously described. The isovolumetric relaxation period lasted equally long, and no difference was found between the rates of ventricular filling during the rapid filling period in the two groups. The peak and mean rates of fibre lengthening were reduced during the early rapid filling period in IHSS. (Auth.)