Evaluating the conditions of patients with congestive heart failure by exercise testing.

To evaluate the conditions of patients with congestive heart failure and to follow up their response to therapy, investigators have used standard clinical classification systems and roentgenographic, ultrasonic, and scintigraphic evaluations of left ventricular function and volumes. While useful in the initial characterization of the patient's condition, many of these measurements are imprecise or detect only small changes after therapy. The functional capacity or cardiac reserve is best evaluated by measuring maximal oxygen consumption during a standard exercise protocol. Potential limitations of exercise testing in following up therapy include the effects of placebo, training, and posture, and the choice of submaximal or maximal testing. The efficacy of investigational inotropic or vasodilator therapy on the patient's central or peripheral circulations should also be measured by hemodynamic monitoring at rest and during exercise to determine the optimal therapy for a particular patient with heart failure.