Pulmonary hypertension due to vasculitis is a rare complication of rheumatoid arthritis (RA). We describe 2 patients with RA and pulmonary hypertension who died with a clinical diagnosis of idiopathic pulmonary hypertension. In each case postmortem examination revealed severe pulmonary vasculitis as the actual cause of the hypertension. Subclinical systemic vasculitis was found in one case and hepatic nodular regenerative hyperplasia in both cases. Pulmonary vasculitis must be included in the differential diagnosis of pulmonary hypertension associated with RA. Open lung biopsy should be considered in this clinical setting in an attempt to identify this potentially treatable cause of pulmonary hypertension.