THE EFFECTS OF EXERCISE TRAINING ON CARDIOVASCULAR STRUCTURE AND FUNCTION IN CONGESTIVE HEART FAILURE
M.M. Parnell*, D.P. Holst, D.M. Kaye.
Alfred Heart Centre and Alfred Baker Medical Unit, Baker Medical Research Institute, Prahran, Victoria.
Total systemic arterial compliance (SAC) contributes to cardiac afterload and is therefore a significant determinant of left ventricular work. Previous studies have suggested that arterial compliance may be reduced in congestive heart failure (CHF) patients. Given data that also show (i) SAC increases after a four-week exercise training program in normal, sedentary individuals and, (ii) CHF patients derive symptomatic benefit from a tailored exercise program, we aimed to investigate the effects of an eight-week exercise training program on arterial compliance, left ventricular dimensions and quality of life in CHF patients. Eighteen subjects (mean±SD; 57±11 years) were randomised to either an exercise training group or a control group where subjects were instructed to continue with their usual lifestyle. The exercise training group significantly increased their exercise capacity after training as measured by a six minute walk test, (mean±SEM; 499±38 to 568±55 metres; p<0.01). SAC increased from 0.59±0.17 to 0.75±0.2 arbitrary compliance units (p<0.05) following the exercise program. Quality of life was significantly improved following involvement in the exercise training program. Depression, measured using the Cardiac Depression Scale, demonstrated an improvement (108±11 to 84±19 units; p<0.01) and heart failure symptoms decreased from 49±26 to 27±14 units (p<0.01), determined using the Minnesota Living with Heart Failure Evaluation. However, left ventricular dimensions determined using M-mode 2D echocardiography, were not significantly altered during the study period. This study demonstrates that an exercise training program improves quality of lire and exercise capacity in CHF patients and that this may be due to an increase in arterial compliance. The beneficial effects of a tailored exercise program for patients with CHF may, in part, be due to an improvement in arterial function.
