title: Unexplained pulmonary hypertension.
mesh_terms: D006801:Humans; D006976:Hypertension, Pulmonary / Q000473:pathology; D011651:Pulmonary Artery / Q000473:pathology; D011655:Pulmonary Embolism / Q000473:pathology; D011667:Pulmonary Veins / Q000473:pathology; D013927:Thrombosis / Q000473:pathology