The effects of supine exercise on left ventricular volume in heart disease

Left ventricular end-diastolic volume (EDV) was measured by thermodilution in 30 patients with heart disease. Those with little physiologic abnormality varied in their response to exertion. In some, EDV decreased while forward stroke volume (FSV) was maintained or increased. In others, EDV and FSV rose during exercise. Patients with aortic insufficiency usually had a decrease in EDV with exercise, whether FSV increased or decreased. In patients with other lesions, FSV and EDV tended to vary together. Changes in EDV and left ventricular end-diastolic pressure with exercise were usually not in the same direction, and the factors which may explain this unexpected finding are discussed. It is concluded that end-diastolic pressure, as usually measured in the left ventricle during cardiac catheterization, will not reliably describe EDV or its changes with exercise.