Pulmonary arterial hypertension in connective tissue diseases

Among connective tissue diseases, pulmonary arterial hypertension (PAH) is frequently associated with systemic sclerosis and systemic lupus erythematosus. PAH is less common in mixed connective tissue diseases and Sjogren's syndrome, and rare in rheumatoid arthritis. PAH in systemic sclerosis may he either isolated (prevalence about 8 %) or associated with interstitial lung disease. Echocardiographic screening for PAH is worthwhile in patients with systemic sclerosis, especially as treatments for idiopathic PAH (endothelin receptor antagonists, phosphodiesterase-5 inhibitors, and prostanoids) are effective in this setting. The prevalence of PAH among patients with systemic lupus erythematosus is poorly known; immunosuppressive treatment is sometimes effective by itself but most patients benefit from PAH treatment. PAH associated with connective tissue diseases has a worse prognosis than idiopathic PAH.