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PubMed · 1817175

[New method for estimating left ventricular myocardial elasticity by vibration analysis].

H Honda·Y Koiwa·T Ohyama·T Takagi·J Kikuchi·N Hoshi·J P Butler·T Takishima
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Abstract

We solved numerical solutions of Advani-Lee's equation, which treats free vibrations of fluid-filled spherical shells, and forms the basis for non-invasive estimation of left ventricular myocardial elasticity. Numerical results showed that elasticity is approximated by E = 86.5.a2.f2 (E: elasticity (dyn/cm2), a: internal radius (cm), f: eigen-frequency (Hz)). To examine the accuracy of this theoretical equation in estimating elasticity, we made 7 spherical shells of silicone rubber, and compared the estimated elasticity by this equation with that by a standard stretch test. The elasticity calculated by Advani-Lee's equation and by stretch test proved to be nearly identical. Therefore, we concluded that we can estimate the elasticity of a spherical shell using this equation. We calculated the myocardial elasticity at the first heart sound emission in 25 normal persons with a simplified (approximated form of) Advani-Lee's equation. The mean elasticity in normal subjects was (7.04 +/- 2.46) x 10(5) dyn/cm2.

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ElasticityHeart Function TestsHeart SoundsHumansVentricular Function, LeftVibrationEnglish AbstractJournal Article

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H Honda, Y Koiwa, T Ohyama, T Takagi, J Kikuchi, N Hoshi, J P Butler, T Takishima. 1991. [New method for estimating left ventricular myocardial elasticity by vibration analysis].. https://pubmed.ncbi.nlm.nih.gov/1817175/

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