Patients with congestive heart failure suffer from decreased exercise tolerance and functional deterioration. Exercise has been shown to increase aerobic capacity, delay anaerobic metabolism and increase vagal tone. Belardinelli and colleagues studied the effect of a long-term moderate exercise program on outcome and quality of life, seeking also to identify patients who benefit the most from exercise training.
In this prospective, randomized controlled trial, 99 of 110 eligible patients with stable, chronic heart failure agreed to participate. Most of the patients were men. Patients were excluded if they had an ejection fraction of greater than 40 percent, arrhythmias, unstable angina, recent acute myocardial infarction, decompensated congestive heart failure, hemodynamically significant valvular disease, uncontrolled hypertension, renal insufficiency or significant pulmonary, orthopedic or neurologic limitations. One half of the patients underwent a 14-month exercise program initiated with a two-month conditioning period consisting of exercise three times per week. The program required a warm-up, followed by riding an exercise bike at 60 percent of their peak oxygen consumption for 40 minutes. After eight weeks, patients dropped down to two exercise sessions per week for 12 months. The control group did not exercise.
Ninety-four patients completed the protocol, with an average attendance at training sessions of 89 percent. No patient had a significant cardiovascular event during training sessions. In the exercise group (but not in the control group), self-reported quality of life questionnaires demonstrated significant and continued improvement starting at two months and continuing throughout the follow-up period. More than half of the patients had cardiac events—37 in the control group and 17 in the exercise group. Of the nonfatal events, eight occurred in the exercise group and 17 in the control group. Hospital readmission rates for heart failure were significantly lower in the exercise group as well.
The authors conclude that a long-term moderate exercise program improves functional capacity and hospital readmission rates in patients with stable chronic heart failure. Quality of life improved for patients in the exercise group in this study, although this hasn't been the case in all studies similar to this one. Mortality is also lower in the exercise group. This benefit can be achieved with only two to three exercise sessions each week.