The disappearance of a third heart sound in a case of calcific pericarditis after surgery together with a quantitative study of the time and frequency relations of the third heart sound in 70 cases suggests that the tensing of the pericardium is a factor in its production. The frequency characteristics of the third heart sound are such that it may be identified in the presence of a diastolic mu...

It is well recognized that a soft first heart sound is frequently found in rheumatic heart disease in children. When this has been marked it has been presumed that a severe degree of carditis existed. It is the purpose of this paper to point out certain relationships regarding the soft first heart sound and the accentuated first sound in rheumatic fever and discuss the reasons for their occurre...

The aim of this study, is to determine whether the fine characteristics of the fetal heart sounds could be used to identify intrauterine growth retarded fetuses. A preliminary evaluation, was conducted to compare these characteristics between intrauterine growth retarded fetuses and normal fetuses in the antenatal period after 36 weeks of gestation. Altogether, 7 IUGR fetuses were compared with...

Pulmonary valve movement and the related acoustic phenomena were investigated using high speed strip-chart echoand phonocardiographic recording. The opening of the pulmonary valve had no definite relationship to the acoustic phenomena, whereas the pulmonary ejection sound was closely related in time to the early systolic maximal opening of the valve. The concomitant pulmonary ejection systolic ...

An early diastolic sound in a patient with apical left ventricular disease is reported. Pulsed Doppler echocardiography showed blood flow within the left ventricular cavity during the isovolumic relaxation period whose peak flow velocity was synchronous with the onset of this diastolic sound. Because it occurred before filling started it could not have been either a third or fourth heart sound....

When an alternating current of high frequency is applied to the thorax, the first derivative of the impedance to this current is affected by the cardiac cycle resulting in a characteristic wave form. Phonocardiograms, electrocardiograms, and first derivative thoracic impedance cardiograms were recorded simultaneously in 91 subjects. The first derivative thoracic impedance cardiograms were found...

The sound pressure correlates of the second heart sound were studied in 22 patients during diagnostic cardiac catheterization. Simultaneous right ventricular and pulmonary artery pressures were recorded with equisensitive catheter-tip micromanometers together with the external phonocardiogram and ECG. In 12 patients having normal pulmonary vascular resistance (group 1), pulmonic closure sound w...