Isometric exercise testing and echocardiography at rest in aortic valve incompetence.

Thirty patients with aortic valve incompetence and 21 control subjects were examined by M-mode echocardiography at rest and radionuclide ventriculography during submaximal handgrip exercise. The patients had greater left ventricular dimensions and end-systolic wall stress values but peak systolic wall stress values did not differ. During exercise the controls' ejection fraction increased by 3 +/- 4%, 95% confidence interval (CI) from +1% to +5%, while the aortic incompetence patients showed no change -1% +/- 5%, CI from -3 to +1%. The 15 symptomatic aortic incompetence patients had a different ejection fraction response from the controls (-2 +/- 4%, p less than 0.01), CI from 4% to +1%, but the 15 asymptomatic patients had not (0 +/- 6%, not significant, CI from -3% to +3%). Three symptomatic and two asymptomatic patients with a decrease in ejection fraction below 5% during handgrip were not identified by left ventricular size and function of systolic loading conditions at rest. Neither echocardiographic or radionuclide parameters of left ventricular size and function at rest correlated with the individual ejection fraction changes during handgrip. Thus, in aortic valve incompetence, the radionuclide angiography assessed functional response to handgrip cannot be predicted by left ventricular size and function or systolic loading conditions at rest.