title: [A study on problems in the diagnosis of primary pulmonary hypertension: report of 11 cases].
mesh_terms: D000293:Adolescent; D000328:Adult; D004452:Echocardiography; D004562:Electrocardiography; D005260:Female; D006344:Heart Septal Defects, Atrial / Q000503:physiopathology; D006801:Humans; D006976:Hypertension, Pulmonary / Q000175:diagnosis* / Q000000981:diagnostic imaging; D008297:Male; D011859:Radiography