Pulmonary arterial hypertension and cor pulmonale were found in a woman with inactive systemic lupus erythematosus (SLE). The patient died of right heart failure 5 years later. Postmortem study showed SLE reparative lesions, plexogenic arteriopathy and vasculitis in the lung vessels. Since no active SLE was found, the pulmonary vasculitis was attributed to plexogenic arteriopathy.