Florid pulmonary veno-occlusive disease. A young woman presented with rapidly progressive dyspnea and clinical findings strongly suggestive of primary pulmonary hypertension or possible pulmonary embolism (or both). She died of acute right-sided heart failure. A diagnosis of pulmonary veno-occlusive disease was made at autopsy. Approximately 100 cases of this disease have been reported previously in the literature. We describe a patient with a particularly florid progression of this unusual disease. Death occurred within six weeks of the onset of symptoms. 