等容舒张期左室心肌松弛性测定的新方法

A NEW METHOD FOR MEASURING LEFT VENTRICULAR ISOVOLUMIC MYOCARDIAL RELAXATION

在７８例接受左右心导管检查的患者中，对等容舒张期（ＩＶＲ）左室压力曲线的下降形式进行了数学分析，并应用简化的指数曲线方程测量了ＩＶＲ左室松弛时间常数（Ｔ）。结果显示，所有患者ＩＶＲ左室瞬时压的对数值与时间呈高度直线相关（ｒ＝０．９３７～０．９９８），理论与实测Ｔ值亦高度相关（ｒ＝０．９６８～０．９８８），表明ＩＶＲ左室压力呈指数曲线下降。本文方法为Ｔ值测量提供了简便可靠的新途径。

To develop a new method for measuring left ventricular myocardial relaxation, the descending limb of the left ventricular pressure curve during isovolumic relaxation was analysed mathematically in 78 cases aged 9-60 yrs. with rheumatic valvular disease, cardiomyopathy, old myocardial infarction, hypertensive heart disease or congenital heart disease who underwent both left and right heart catheterization, and the left ventricular isovolumic relaxation time constant (T) was calculated using a simplified exponential equation. The result showed that in all cases there was a significant linear correlation between the natural logarithmic value of the left ventricular instantaneous pressure and time during isovolumic relaxation (r=0. 937 - 0. 998, p<0. 001),and theoretically-calculated T correlated significantly with T measured from pressure curves (r=0. 968- 0. 988, p<0. 001). These results demonstrated that left ventricular pressure declines exponentially during isovolumic relaxation and our method offers a simple and reliable approach to the quantitative assessment of left ventricular myocardial relaxation.