Intracardiac phonocardiography in the diagnosis of large patent ductus arteriosus in early infancy

Ten infants under 6 months of age in congestive heart failure have been studied and were proved to have only a large patent ductus arteriosus. Auscultation and phonocardiography of the chest wall showed only a systolic murmur along the left sternal border. Intracardiac phonocardiography revealed a continuous murmur inside the pulmonary artery in 9 out of the 10 cases. The role of intracardiac phonocardiography in the diagnosis of large patent ductus arteriosus in early infancy is emphasized.