Acoustic Mapping within the Heart

Abstract

A cylindrical barium titanate element has been placed at the distal end of a specially designed catheter and used in studies of the heart sounds of dogs and humans. Heart sounds have been recorded with the element located in the four chambers of the heart as well as in the great vessels leading from the heart. X-ray photographs monitored the location of the catheter tip in each case. The sounds have been recorded on tape and simultaneously on a photographic galvanometer recorder, all studies were continuously monitored by electrocardiogram. Sound spectrographic analysis of the several sounds was made and analyzed.

Comparison of the frequency response characteristics of catheter‐mounted piezoelectric and micromanometric phonotransducers

“…Cardiac auscultation has been a mainstay of clinical practice for centuries [6]. Heart sounds provide information about cardiac contractile state, heart rhythm, and acquired and congenital disorders of the heart and vessels [7-91.…”

“…Catheter-mounted phonocardiographic transducers were first introduced in the 1950s [l]. Early studies were useful in establishing the risk associated with passing sound catheters and identifying sites of greatest intensity of heart sounds and murmurs [6][7][8]12,13]. Four types of systems have been used in the catheterization laboratory to record intravascular sounds: 1) condenser microphones, 2 ) piezoelectric transducers, 3) fluid column transmission systems, and 4) micromanometric transducers.…”

“…Intravascular piezoelectric phonotransducers using barium titanate transducer elements were employed in 1957 by Lewis and Wallace [6,12]. These transducers were attached to single 5F or double lumen 7 1/2F catheters.…”

Phonocardiography in the Horse: 1. The Intracardiac Phonocardiogram

“…THE technique of intracardiac phonocardiography was described in detail by Yamakawa, et al (1954). Since then many papers have appeared describing successful recording of sounds directly from the chambers of the human heart (Soulit, et al, 1954;Lewis, Deitz, Wallace and Brown, 1957;Wallace, Brown, Lewis and Deitz, 1957;Laurens, eta/., 1959;Beuren and Apitz, 1963;Luisada, Liu, Szatkowki and Slodki, 1963 ;Kosmak, et al, 1964;Resnekov and Somerville, 1964;Segal, Novak and Kasparin, 1964;Dahl, 1966;Wennevold, 1966Wennevold, , 1967Wennevold, , 1968O'Toole, et al, 1976;Sabbah and Stein, 1976a, b).…”