Several small studies have reported benefits from exercise training in patients with chronic heart failure, but the overall risks and benefits of exercise in patients with this increasingly common condition have not been determined. The ExTraMATCH international collaborative group conducted a meta-analysis to compare the effects of exercise training with usual care in patients with chronic heart failure caused by left ventricular systolic dysfunction.
They searched electronic databases for randomized controlled studies conducted since 1990 that included medically supervised exercise programs of at least eight weeks’ duration in patients with stable heart failure and a left ventricular ejection fraction of less than 50 percent. The investigators of the nine eligible studies provided original data for analysis. The outcomes of interest were time to death and time to admission to the hospital for any cause. The studies included nearly 400,000 patients, and the mean follow-up period ranged from 22 to 1,213 days. On average, patients were about 60 years of age and had a 2.5 New York Heart Association classification for heart failure. Approximately 88 percent of participants were men. Different forms and intensity of exercise were used, including supervised cycling or walking, aerobic training, calisthenics, and interval training. Intensity measures included targets of 60 to 80 percent peak oxygen consumption and 60 to 80 percent peak heart rate. No evidence of publication bias was found.
The 88 deaths in the exercise group occurred at a median time of 618 days compared with 421 days for the 105 deaths in the control group. The significantly lower mortality in the exercise group was equivalent to a number needed to treat of 17 to prevent one death within two years. The median time to admission to the hospital for any reason also was significantly longer in the exercise group (426 compared with 371 days). No specific subgroup of patients, regardless of gender, heart failure classification, or degree of severity, appeared to benefit disproportionately from exercise. Exercise programs lasting more than 28 weeks appeared to have outcomes similar to shorter programs.
The authors conclude that medically supervised exercise training significantly improves survival and reduces hospital admission in patients with chronic heart failure caused by left ventricular systolic dysfunction. The effect appears to apply to all types of heart failure and across the full spectrum of patient characteristics. The authors call for more studies to better delineate the most effective types, duration, and intensity of exercise for patients with heart failure.
editor’s note: Many patients with heart disease are reluctant to exercise because of well-founded beliefs and common reports of heart patients dying during physical exertion (or memories of exercise-induced symptoms). This study indicates that mortality and hospital readmission rates improved in stable patients with heart failure who took part in supervised exercise programs. The key is in selection of patients and well-designed, supervised exercise plans. Family physicians may have to spend as much time persuading the overambitious cardiac patient to moderate strenuous exercise as encouraging the reluctant sedentary patient to start walking. As in most things, our skill in personalizing the research and giving expert advice to individual patients is of paramount importance. Tenacity, knowing local resources, and calling on family members to encourage patients and exercise with them are helpful.—a.d.w.