Exercise Training in Pulmonary Hypertension

The response to exercise training reported in this issue of Circulation 1 should change the way we perceive and treat selected patients with pulmonary hypertension (PH) and brings into focus the problem of measuring the effects of drug therapy in this condition.2Article p 1482 In a highly structured 15-week program of daily exercise, patients with PH experienced a mean increase of 96±61 meters in the 6-minute walking test from a baseline of 439±82. The increase in the 6-minute walking distance after exercise training was greater than that achieved with prostacyclin formulations, endothelin receptor antagonists,3 and phosphodiesterase inhibitors. By comparison, the baseline and incremental increases in the 6-minute walking distance in studies of successful drug therapies range from a low of 297+31 meters with epoprostenol4 to 342+51 with sildenafil.5 The study group consisted of 24 patients with idiopathic pulmonary arterial hypertension and 6 patients with chronic thromboembolic PH. Fifteen patients were initially entered into the active exercise program, and 15 control patients crossed over to the exercise program after the first 15 weeks. Although not explicitly stated, it appears that there were no patients with the scleroderma spectrum of disease entered in the study, presumably because of the inability to exercise. Other patients with musculoskeletal limitations were excluded as well. Clearly, the cohort in the present study had a higher baseline physical capacity than patients reported in most drug trials, and this may be partly responsible for the greater increase in 6-minute walk than previously reported. …