title: Abnormal pulmonic sound during acute massive pulmonary embolism.
abstract: The findings in two patients with angiographically proven massive pulmonary embolism and with clinical and phonocardiographic evidence of abnormal respiratory movement of the pulmonic sound are reported. One patient with complete right bundle-branch block and another with normal conduction had a wide and fixed split second sound with a loud pulmonic component. Both patients had a moderate degree of pulmonary hypertension. Approximately two weeks after administration of heparin, the pulmonic sound moved normally during respiration in both patients. Thromboembolic pulmonary hypertension regressed in one patient and remained unchanged in the other. Changes in impedance through the large pulmonary arteries are are postulated to be responsible for the abnormal movement of the  pulmonic valve during both phases of respiration. Wide expiratory splitting of the second sound should be an important clue in the diag nosis of acute massive pulmonary embolism, and the reappearance of a normal inspiratory splitting could be used at the beside to assess indirectly the rate of resolution of the blood clots.
mesh_terms: D000208:Acute Disease; D000368:Aged; D004562:Electrocardiography; D005260:Female; D006326:Heart Auscultation; D006347:Heart Sounds; D006801:Humans; D006976:Hypertension, Pulmonary / Q000175:diagnosis; D008297:Male; D008875:Middle Aged; D010701:Phonocardiography; D011651:Pulmonary Artery / Q000000981:diagnostic imaging; D011655:Pulmonary Embolism / Q000175:diagnosis* / Q000000981:diagnostic imaging; D011859:Radiography