Response of Left Ventricular Volume and Ejection Fraction to Exercise in Normal Persons and Patients With Angina Pectoris

Abstract

The response of the left ventricle to exercise-induced stress has been of interest to cardiologists and physiologists for many years [1–3]. It is clinically relevant to the problems associated with the detection of latent coronary artery disease and establishing the hemodynamic significance of suspicious lesions. Borer et al. [4] recently demonstrated that nontraumatic gated equilibrium radionuclide angiography could be used to separate persons with a normal ejection fraction response to stress from patients with coronary artery disease in whom ejection fraction fails to increase or even falls with exercise. Prior to this, exercise-induced changes in ventricular function could be assessed only be direct measurements of left ventricular pressure at cardiac catheterization or by contrast ventriculographic calculations of ventricular volume at rest and at peak exercise by using area-length formulae based on certain geometric assumptions concerning ventricular shape [1, 3]. While current nuclear angiographic methods can accurately determine ejection fraction without the need to directly calculate chamber volume, the assessment of left ventricular volume by radionuclide angiography has until now required essentially the same type of area-length measurements required for contrast ventriculography and echocardiography [5].