Chronic heart failure (HF) is a syndrome of impaired ventricular function resulting in clinical symptoms of fatigue, dyspnea, and decreased exercise capacity. These symptoms lead to a cyclical pattern of an increasing sedentary lifestyle with accompanying deconditioning and deterioration of muscle function. Until recently, the prescription for individuals with HF was rest and minimization of physical exertion.
The primary objectives of this randomized clinical trial were to determine whether subjects, with moderate to severe chronic HF, who completed a 12-week individualized program of cardiopulmonary training (exercise group) would have significantly greater (i) quality of life, measured by the Rand Short Form-36, and (ii) aerobic fitness, measured by oxygen uptake during symptom limited maximal metabolic treadmill testing, than subjects who met weekly with an investigator and received vital sign measurements (non-exercise group).
A randomized controlled clinical trial was utilized. Individuals who met the inclusion criteria were randomly assigned to either an exercise or control group. Individuals in the exercise group received 36 weeks of exercise training (primary outcome variables were measured at 12 weeks). Participants in the control group received weekly visits with a nurse for 12 weeks.
Fifty-one male volunteers gave written informed consent. Thirty-one of these subjects completed baseline testing and were randomized 15 into the exercise (62.8±10.5 yr of age, LVEF 29.8±6.9) and 16 into the non-exercise control (66.6±9.6 yr of age, LVEF 29.2±6.5). Subjects in the exercise group participated in a 12-week supervised moderate intensity PoleStriding aerobic exercise program (three times per week for the first six weeks, thereafter visits were reduced to two times per week). Non-exercise group subjects came to the laboratory weekly for 12 weeks for vital sign measurements. Quality of life was measured by the Rand SF-36, the Minnesota Living With Heart Failure Questionnaire and the Cardiac Exercise Self-Efficacy Instrument. Significant improvements in physical function subscale of the SF-36 were observed in the exercise group when compared to the non-exercise control group (P = 0.007). No significant differences were found on the remaining subscales of the SF-36 fundamentally because subject scores, before randomization, were within ± one standard deviation from norms for apparently healthy individuals. After 12 weeks a 9% increase in oxygen uptake in the exercise group (17.52±6.07 to 19.10±5.42) was significantly greater than the non-exercise group P=0.014. The exercise group continued to improve over baseline (16%) at 24 weeks and showed a clinically significant decrease in functional aerobic impairment. Subjects in the exercise group reported a significant decline in perceived difficulty in dealing with symptoms from heart failure (32%, P < 0.04), whereas non-exercising control subjects showed no change. A 17% improvement in self-efficacy for exercise was observed in the exercise group and no change was found in the non-exercise control group. A modest 9% improvement in self-reported kilocalorie expenditure in the exercise group and a 5% improvement were noted in the non-exercising control group. During the intervention period the exercise group had significantly more outpatient visits (P = 0.001) but a similar number of inpatient admissions. The results of this randomized controlled clinical trial provide empirical evidence that moderate exercise training in subjects with chronic heart failure significantly improves perceptions of physical function (P = 0.007) and aerobic power (P = 0.014) when compared to non-exercising control subjects. Subjects’ responses on the Living with Heart Failure Questionnaire indicates that a supervised 12-week program of exercise training results in a marked decrease in heart failure patients’ perceived difficulty with symptoms from heart failure.
Exercise training in patients with heart failure is a viable intervention to improve their quality of life.
External Links for this Project
- Collins E, Langbein WE, Dilan-Koetje J, Bammert C, Hanson K, Reda D, Edwards L. Effects of exercise training on aerobic capacity and quality of life in individuals with heart failure. Heart & lung : the journal of critical care. 2004 May 1; 33(3):154-61. [view]
- Collins EG, Langbein E, Orebaugh C. Can exercise training improve QOL in heart failure patients? A pilot study. Paper presented at: International Society for Heart & Lung Transplantation Annual Meeting; 1998 Jun 1; Chicago, IL. [view]