Honda H, Koiwa Y, Ohyama T, Takagi T, Kikuchi J, Hoshi N, Butler J P, Takishima T
First Department of Internal Medicine, Tohoku University School of Medicine, Aoba-ku Sendai.
J Cardiol. 1991;21(1):157-61.
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.
我们求解了阿德瓦尼-李方程的数值解，该方程用于处理充满流体的球壳的自由振动，是无创估计左心室心肌弹性的基础。数值结果表明，弹性可近似表示为E = 86.5.a2.f2（E：弹性（达因/平方厘米），a：内半径（厘米），f：固有频率（赫兹））。为检验该理论方程在估计弹性方面的准确性，我们制作了7个硅橡胶球壳，并将该方程估计的弹性与标准拉伸试验得到的弹性进行比较。结果证明，由阿德瓦尼-李方程计算得到的弹性与拉伸试验得到的弹性几乎相同。因此，我们得出结论，可使用该方程估计球壳的弹性。我们用简化的（近似形式的）阿德瓦尼-李方程计算了25名正常人第一心音发射时的心肌弹性。正常受试者的平均弹性为(7.04 +/- 2.46) x 10(5)达因/平方厘米。
