Effects of Atrial Fibrillation on Exercise Performance in Patients with Cardiac Disease

Cardiac performance in 25 male and 40 female cardiac patients with atrial fibrillation was compared with that of age, sex, and function-matched controls with sinus rhythm. All had rheumatic valvular heart disease treated with digitalis. Multistage maximal exercise was tested on a motor-driven treadmill with increasing work loads every 3 minutes to the limits of fatigue. Mean heart rates of patients with atrial fibrillation were greater at rest, at all levels of exercise, and immediately after it regardless of sex or anatomic lesion; however, recovery heart rate was significantly higher in the males than in the females with sinus rhythm. As is true for normals, mean duration and intensity of exercise was greater in male than in female cardiac patients regardless of rhythm or anatomic lesion.