ISSN:
1741-0444
Keywords:
Fast Fourier transform
;
In vitro comparison
;
Sound
;
Starr-Edwards 2400 prosthesis
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Chemistry and Pharmacology
,
Medicine
Notes:
Abstract A comparative study was made of the sounds produced by a normal Starr-Edwards 2400 aortic valve prosthesis with those produced by the same valve but having a simulated overgrowth at the apex of the struts. Comparisons were made over the entire cardiac cycle for time and amplitude, power-density spectra, power-distribution spectra, power-distribution surfaces associated with individual valves, and three-dimensional power-distribution-difference surface. Power-density spectra were compared for portions of the cycle corresponding to the opening, systolic, and closing sounds of the valve. Physical parameters of an acoustical model were estimated from the power-density spectra. The results showed that each comparison gave information pertinent to the simulated malfunction. Opening. systolic and closing sounds, respectively, were different for each valve. The opening sound of the abnormal valve displayed a much lower frequency. Systolic sounds for the two valves were similar in frequency, but the normal valve produced more total power for this sound. The closing sound of the abnormal valve occurred later than that of the normal valve. These differences were more clearly seen when viewed in the frequency domain.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF02443744
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