Intracardiac Phonocardiogram in Thirty Cases of Atrial Septal Defect

Abstract

Thirty cases of atrial septal defect proved by cardiac catheterization, surgery, or postmorten examination have been investigated with the technic of intracardiac phonocardiography, which provided precise localization of the source of heart sounds and murmurs. The site and mechanism of origin of the many auscultatory signs in uncomplicated atrial septal defect and in cases of Lutembacher's syndrome, tricuspid atresia, and persistent atrioventricular canal were elucidated by direct intracardiac sound recordings and simultaneous external chest phonocardiograms.THERE have been many recent reports of the auscultatory features of atrial septal defect and these have been reviewed both clinically and with the aid of chest phonocardiography.1-7The commonest auscultatory findings in uncomplicated atrial septal defect are a basal systolic ejection murmur, usually soft, and a wide, fixed splitting of the second sound over the pulmonary area. Less frequently an early blowing diastolic murmur is heard at the base and along the left sternal border iii the second and third left intercostal spaces. At the apex, or medial to it, systolic and diastolic murmurs may occasionally be present, together with an accentuated first sound. The systolic apical murmur is usually of regurgitant type (pansystolic) ; the diastolic apical murmur occurs in mid-diastole or inpresystole.There appears to be no general agreement about the site and mechanism of production of these signs. The relative importance of various factors such as the flow across the atrial septal defect, the increased flow through the tricuspid and pulmonary valves, and the From the

Phonocardiography in Atrial Septal Defects of the Osthim Secundum Type

“…A high pitched early diastolic sound-a tricuspid opening snap (8), was recorded in five cases. Three showed significant shunts and in the other two a mid diastolic murmur also suggested an increased flow through Ihe tricuspid valve (7,3,12).…”

“…An earlj' basal diastolic murmur known to be due to pulmo nary insufficiency (7,2) was recorded in 5 cases, all with very high pulmonary artery pressures (Fig. 3).…”

Phonocardiographic analysis of diastolic flow murmurs in secundum atrial septal defect and ventricular septal defect.

“…Intracardiac phonocardiography has provided support for the theory that the diastolic "flow rumble" of atrial septal defect originates at the tricuspid valve and that of ventricular septal defect at the mitral valve (Liu and Jacono, 1958;Feruglio and Sreenivasan, 1959;Feruglio and Gunton, 1960). It is commonly accepted that the presence of a "flow rumble" indicates a rather large left-to-right shunt (Wood, Magidson, and Wilson, 1954;Leatham and Segal, 1962;Segal, Novack, and Kasparian, 1964).…”

Phonocardiography in Clinical Practice

“…The phenomenon whereby an aortic systolic murmur seems loudest at the apex may be explained by considering that such murmurs have two chief components: noisy qualities produced by the jet of blood in the aorta and musical qualities generated by the stenotic valve leaflets. 8 The latter vibrations are best transmitted to the apex; the noisier components follow the course of the great arteries. Hence when the valvular factor is pronounced and overshadows the jet factor, the murmur is most easily appreciated inferiorly, and very little murmur is heard in the primary aortic area and neck.…”