Peripheral muscle dysfunction in pulmonary hypertension

The prognosis of idiopathic pulmonary arterial hypertension (IPAH) has recently improved as a result of novel specific therapies. However, some treated patients with IPAH may have persistent dyspnoea and exercise intolerance. In this issue, Mainguy and colleagues describe a study of peripheral muscle function, morphology and the enzymatic profile in IPAH. The authors report significant morphological and functional changes in the quadriceps of patients with IPAH with a lower proportion of type 1 fibres, a lower maximal voluntary contraction and a higher potential for anaerobic than aerobic metabolism. Some of these changes correlated with the patients' functional capacity. In the accompanying editorial, Nathan and Fuld discuss the results and point out that, while the study …