Ventricular Volume Studies in a Patient with Hypertrophic Subaortic Stenosis

Left ventricular volume studies were performed on a patient with hypertrophic subaortic stenosis utilizing cineangiocardiography. During the injection of contrast material the patient had a premature ventricular contraction followed by sinus rhythm. The ventricular volume measurements were made during the post PVC beat and subsequent sinus beats. The volume studies revealed normal end-diastolic volumes and small end-systolic volumes with an increased ejection fraction. Although the left ventricular stroke volume was greater during the post PVC beat than during subsequent beats, the simultaneous arterial systolic and pulse pressure did not rise. The elevated diastolic filling pressure, the normal end-diastolic volumes, and the failure of the end-diastolic volume to increase with a longer diastolic filling period are compatible with diastolic restriction in hypertrophic stenosis.