Effects of isometric exercise on the diastolic function in patients with severe aortic stenosis with or without coronary lesion

Background There is no literature evaluating the effect of exercise on patients with aortic stenosis, in which patients with and without coronary artery disease were assessed separately. Objective To assess the effects of isometric exercise on the diastolic function in patients with aortic stenosis (AS). Methods 18 patients with AS, and 5 control patients were studied (group 1, G1). Patients with AS were divided in: group 2 (G2, n=10), without coronary lesion, and group 3 (G3, n=8), with coronary lesion. All patients underwent cardiac catheterization and performed isometric exercise until heart rate increased 32±9%. Left ventricular systolic pressure and end diastolic pressure (LVEDP), t1/2 (relaxation index), and the +dP/dtmax were all measured. Results The +dP/dtmax increased in G1, G2, and G3 during exercise returning to their basal values once exercise had concluded. While exercising, the LVEDP increased in G1, G2 and G3, returning to its original baseline value only in G1 and G2. The t1/2 increased, while exercising, in G2 and G3, and continued to be elevated after the exercise in both groups although it was only statistically significant in G3. The control group did not show significant changes. Conclusions Isometric exercise decreases relaxation rate and increases LVEDP in patients with AS. After exercise, relaxation and LVEDP remained altered only in the patients with coronary lesion. The alteration in lusitropism and increased LVEDP after exercising suggest the presence of stunned myocardium.