Evaluation of the response to pharmacological stress in chronic aortic regurgitation.

We evaluated the hemodynamic response of patients with chronic aortic regurgitation and decreased ejection fraction (EF), mean value +/- SD (37 +/- 9), to dobutamine stress echocardiography (DSE). Eleven patients were studied with DSE. Nine patients were in New York Heart Association (NYHA) Class II and two in NYHA Class III. Ten patients received medical treatment in the only other periodic evaluation. With DSE in nine patients, a significant decrease in left ventricular end-diastolic and end-systolic diameters (LVEDD and LVESD) as well as LV end-diastolic and end-systolic volumes (LVEDV and LVESV) was documented in comparison to resting values. EF and fractional shortening (FS) improved significantly with DSE. Systolic wall stress (SWS) and pulmonary arterial systolic pressure (PASP) did not change. Average follow-up was 6.7 months. Three patients underwent valve replacement with mechanical prostheses. Two of them are in NYHA Class I and the other died of LV failure 3 days after surgery. One patient deteriorated beyond surgical treatment and was in NYHA Class II. The other seven patients remain in NYHA Class II and await valve replacement. In patients with chronic aortic regurgitation and depressed EF, the variables relevant to myocardial reserve appear to be EF, FS, LVEDD, LVESD, LVEDV, and LVESV.