Left Ventricular Response to Isometric Exercise in Aortic Valve Diseases and Its Value in the Optimal Timing of Aortic Valve Replacement

In order to evaluate the left ventricular response to isometric exercise in different types of aortic valve disease, isometric exercise tests were performed during cardiac catheterization in 14 patients with pure aortic stenosis, 20 with combined aortic stenosis and regurgitation, and 18 with pure aortic regurgitation. Patients with angina pectoris in whom coronary angiography had not been performed were excluded. Thirty-seven patients were recatheterized 12 months after aortic valve replacement, and the ventricular response to exercise was re-evaluated. Preoperatively, the ejection fraction did not change significantly during exercise in patients with aortic stenosis, tended to decrease in patients with combined valve lesion, and decreased significantly in patients with aortic regurgitation (p less than 0.001). In the three patients whose ejection fraction during preoperative exercise decreased to below 0.40, it remained below 0.50 after successful aortic valve replacement. It appears possible to reveal left ventricular dysfunction in many patients with aortic regurgitation and in some with combined aortic valve disease by means of isometric exercise. The severely depressed ventricular dysfunction during exercise does not appear to correct totally after surgery.