[Functional state of the left heart in aortic regurgitation of varying degrees]

An attempt was made to noninvasively assess the myocardial reserve by using a bimanual isometric exercise (BIE) in patients with aortic failure depending on the degree of aortic regurgitation (AR). The patients with Grade I AR, like healthy subjects, showed their responses to BIE, by significantly enhancing systolic BP, heart rate (HR), left ventricular ejection fraction (LVEF), stroke index and decreasing the end systolic volume of the left ventricle, which indicated that the left ventricle had great compensatory potentialities. With physical exercise, the patients with Grade II AR displayed an inadequately small increase in LVEF and velocity of myocardial circular fiber contractions, which suggested latent ventricular failure and was an indicator of diminished myocardial reserve. In response to BIF, there was a significant reduction in LVEF along with a substantial increase in the maximal size of the left atrium in the patients with Grade III AR, attesting that myocardial functional potentialities were considerably reduced.