Title :
Effects of thrombus simulants on acoustic characteristics of artificial heart-valves
Author :
Lariviere, J. ; Mussivand, T. ; Goubran, R.
Author_Institution :
Dept. of Syst. & Comput. Eng., Carleton Univ., Ottawa, Ont., Canada
Abstract :
Thrombus simulants were attached to the inflow valve housing and in-vitro sound recordings were made of mechanical aortic valves in a mock circulatory loop driven by a pulsatile artificial heart (ventricle). The valves were isolated from the ambient sound by means of a semi-anechoic chamber. Nine trials of >60 cycles each were recorded and the power spectra within 10 frequency bands (from 0 to 1000 Hz) were calculated using pole-zero modelling and Fast Fourier Transforms (FFTS) and submitted to ANOVA (analysis of variance) tests. FET results showed a significant difference (p<0.01) in power levels within the 650 to 750 Hz band between valves with and without thrombus simulants when blockage exceeded 10% of total flow area. Pole-zero results showed a significant difference (p<0.05) when blockage exceeded 25% of total flow area
Keywords :
bioacoustics; cardiology; fast Fourier transforms; poles and zeros; prosthetics; 0 to 1000 Hz; acoustic characteristics; artificial heart-valves; fast Fourier transforms; in-vitro sound recordings; inflow valve housing; mechanical aortic valves; mock circulatory loop; pole-zero modelling; power spectra; pulsatile artificial heart; semianechoic chamber; thrombus simulants effects; Analysis of variance; Anechoic chambers; Arteries; Artificial heart; Frequency; Heart valves; Microphones; Pulse circuits; Surface impedance; Testing;
Conference_Titel :
Engineering in Medicine and Biology Society, 1995., IEEE 17th Annual Conference
Conference_Location :
Montreal, Que.
Print_ISBN :
0-7803-2475-7
DOI :
10.1109/IEMBS.1995.579360
