Rate of Change in Physical Fitness and Quality of Life and Depression Following Exercise Training in Patients With Congestive Heart Failure

Abstract

Exercise training appears to improve peak oxygen consumption (VO₂) and quality of life (QOL) in heart failure patients, although disease etiology, patient demographics and medication may alter the rate of adaptation. The authors sought to identify rate of change from baseline in fitness, QOL, and depression following exercise training in a cohort of patients with congestive heart failure. Thirty male systolic heart failure patients (aged 63.8±8.3 years, baseline peak VO₂ 12.2±4.8 mL/kg/min, left ventricular ejection fraction 28.2±9.4%, New York Heart Association class II/II 22/8) undertook 52 weeks of exercise training, 16 weeks as an outpatient and a further 36 weeks of home exercise. Peak VO₂ and QOL was measured using the Minnesota Living With Heart Failure (MLWHF) questionnaire and depression using the Hare-Davis scale. The authors analyzed the rate of change in peak VO₂ and MLWHF after grouping patients according to clinical, demographic, and pharmacologic characteristics. Peak VO₂ measurements varied over time, with no effect of disease pathology or β-blocker on peak VO₂. The rate of change in physical MLWHF score was significantly greater (improved) during 0 to 16 weeks in patients with dilated pathology, but was not significantly affected by β-blocker use or age. The exercise training venue and supervision, or lack thereof, is the major determinant of adaptation to the intervention in heart failure patients, although age, β-adrenergic medication, and heart failure etiology also explain some of the variation in adaptive responses observed.