Pulmonary arterial hypertension associated to connective tissue diseases.

Pulmonary arterial hypertension is a well-known complication of connective tissue diseases such as systemic sclerosis, systemic lupus erythematosus, mixed connective tissue diseases, and to a lesser extent, rheumatoid arthritis, dermatopolymyositis and primary Sjögren's syndrome. In these patients, pulmonary hypertension may occur in association with left heart disease, interstitial fibrosis or as a result of a isolated pulmonary arteriopathy. The incidence of pulmonary arterial hypertension in the limited form of systemic sclerosis is about 10%. The pathophysiologic mechanisms leading to pulmonary arterial hypertension remain unknown. Symptoms and clinical presentation are very similar to idiopathic pulmonary arterial hypertension but mortality was confirmed to be higher. Echocardiography is the reference investigation for the detection of pulmonary arterial hypertension but the results should be confirmed by right heart catheterization. Treatment appears more complex as compared to idiopathic pulmonary arterial hypertension. Intravenous epoprostenol therapy has been shown to be effective in a special trail. Also, the endothelin receptor antagonists bosentan and sitaxentan, the phosphodyesterase-type-5 sildenafil and subcutaneous treprostinil have shown favourable results.