Phonocardiographic Diagnosis of Aortic Ball Variance

Abstract

Fatty infiltration causing changes in the silastic poppet of the Model 1000 series Starr-Edwards aortic valve prostheses (ball variance) has been detected with increasing frequency and can result in sudden death. Phonocardiograms were recorded on 12 patients with ball variance confirmed by operation and of 31 controls. Ten of the 12 patients with ball variance were distinguished from the controls by an aortic opening sound (AO) less than half as intense as the aortic closure sound (AC) at the second right intercostal space (AO/AC ratio less than 0.5). Both AO and AC were decreased in two patients with ball variance, with the loss of the characteristic high frequency and amplitude of these sounds. The only patient having a diminished AO/AC ratio (0.42) without ball variance at reoperation had a clot extending over the aortic valve struts. The phonocardiographic findings have been the most reliable objective evidence of ball variance in patients with Starr-Edwards aortic prosthesis of the Model 1000 series.

Systolic Time Intervals, Phonocardiograms and Sound Spectrograms in Patients with Starr-Edwards Aortic Valve Prostheses

“…For the early recognition of valvular dysfunction in Starr-Edwards aortic valve prostheses model 1000, Hylen et al [8] introduced the estimation of the AO/AC ratio on phonocardiograms recorded from the second right intercostal space. Unfortunately, this ratio displayed a wide scatter for reasons which arc not clear.…”

“…Since the introduction of prosthetic ball valves in the surgical treat ment of valvular heart disease, ball variance has been reported in a sub stantial number of patients [8][9][10]13]. Left untreated, this mechanical dysfunction can result in sudden death.…”

“…Therefore, an early diagnosis and reoperation are important. A method for detecting dysfunction of the valve prosthesis relies on comparing the intensity of the prosthetic aortic opening sound with that of the closing sound (AO/AC ratio) on the phonocardiogram [8]. Hylen et al have also introduced a sound spectrographic method to improve the accuracy of diagnosis of ball variance [9,10].…”

Sound Spectroanalytic Diagnosis of Malfunctioning Prosthetic Heart Valve

“…preamplifier, a filter (160/24 db octave) and a sound spectrograph (Rion Co. S.G. (7). Contour sound spectrograms (SSG) were drawn and peak frequency, wave pattern and frequency-intensity curves were investigated as characteristics of implanted valvular function.…”

“…Evaluation of implanted prosthetic valvular function and diagnosis of malfunc tion have been done by means of phonocardiography (Hylen et al 1968; Osawa et al 1972), cineangiocardiography (Linhart and Wheat 1966;Edgett et al . 1967) and echo-cardiography (Johnson et al .…”