Exercise tolerance measurements in pulmonary vascular diseases and chronic heart failure

The hallmark symptoms of heart failure are dyspnoea and fatigue during exercise. In recent years, the physiologic response to progressive exercise using direct measures of ventilation and gas exchange, commonly termed the 'cardiopulmonary exercise test' (CPET), has evolved into an important clinical tool in the management of patients with heart failure. CPET provides a global assessment of the integrated response to exercise involving the pulmonary, cardiovascular, haematopoietic, neuropsychological and skeletal muscle systems. This information cannot be obtained through investigation of the individual organ system in isolation. The noninvasive, dynamic physiologic overview permits the evaluation of both submaximal and peak exercise responses providing the physician with relevant information for clinical decision making. The use of CPET in the management of chronic heart failure patients is increasing, with the understanding that resting pulmonary and cardiac function testing cannot reliably predict exercise performance and functional capacity and that, furthermore, overall health status and prognosis are better predicted by indices of exercise tolerance than by resting measurements.