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Pulmonary arterial hypertension (PAH) is a recognized but rare complication of rheumatoid arthritis (RA). Different pathologic lesions have been described, including inflammatory pulmonary vasculitis and the more classic plexiform vasculopathy with intimal hyperplasia and smooth muscle hypertrophy. Therefore, treatment of RA-associated PAH may require aggressive immunomodulatory therapy in addition to the standard PAH drugs. Case studies also report PAH resulting from chronic venous thromboembolic disease and occasionally complicating overlap syndromes, particularly in patients with coexisting clinical serologic characteristics of scleroderma.

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