Hypertrophic subaortic stenosis: Clinical and hemodynamic studies with special reference to pulse contour measurement ∗

Abstract

Three cases of hypertrophic subaortic stenosis are presented. The following clinical and hemodynamic characteristics are demonstrated: 1. 1. A diamond-shaped holosystolic murmur was present at the fifth left intercostal space, inside the cardiac apex; the aortic second sound was well heard. The murmur was less intense at the base and not transmitted well into the neck. 2. 2. There was synchronism of the rapid upstroke time and slope of the simultaneously recorded left ventricular and central aortic pressure curves. Also present was a parallelism of the radial artery upstroke time with that of the central aortic pressure curve. A prolonged ejection time was seen and a large secondary systolic wave, representing the subaortic muscular obstruction, was noted. 3. 3. It is our belief that the unusual central and peripheral arterial pulse contour in hypertrophic subaortic stenosis represents, by itself, a diagnostic feature of this disease if not complicated by other anomalies. 4. 4. The beats following premature ventricular contractions always exhibited lower arterial pulse pressure than did the normal beats. 5. 5. Angiocardiography showed a cone formation and marked diminution of the outflow tract lumen during systole, about 3 cm. below the valve, and normal contour of the valvular cusps. 6. 6. Of special interest is that two of the three patients had subacute bacterial endocarditis, responding to penicillin therapy. 7. 7. One patient died following attempted surgical correction of the hypertrophic subaortic stenosis.