Functional capacity of patients with chronic left ventricular failure

Upright bicycle exercise to symptomatic maximum and anaerobic threshold was performed by 44 male patients with clinical class II to IV chronic congestive heart failure and in 16 similarly aged normal male volunteer subjects.

Abstract

Severity of congestive heart failure is usually graded by clinical and resting hemodynamic criteria, although patients are most often symptomatic during exertion. Upright bicycle exercise to symptomatic maximum and anaerobic threshold was performed by 44 male patients with clinical class II to IV chronic congestive heart failure, and in 16 similarly aged normal male volunteer subjects. Patients achieved a maximal oxygen consumption of 13.3 ± 0.8 (SEM) ml/kg/min compared to 21.9 ± 1.2 ml/kg/min in normal subjects (p 20, II = 14–20, III = 10–13, IV = < 10. These groups were clearly separated by exercise duration but not by hemodynamic parameters at peak exercise. Clinical classification of patients (New York Heart Association criteria) agreed with the exercise classification in only 16 of 44 patients. Resting heart rate, blood pressure, cardiac index and pulmonary wedge pressure also failed to correlate with exercise capacity. Thus, maximal exercise testing is preferred to grade the symptomatic severity of congestive heart failure.