无心跳供者心脏热缺血及冷保存过程中心肌活性的检测

Evaluation of non-beating heart graft viability by dielectric analysis and myocardial tactile sensor system

目的:探索一种简单而且迅速地检测无心跳心肌活性的方法,对热缺血和冷保存过程中无心跳心肌介电特性和心肌硬度的变化进行探讨。方法:杂种小猪随机分成对照组和实验组,呼吸机停止前15min,分别静注等渗盐水及前列腺素E1(PGE1)。窒息诱导心脏停跳,供者心暴露在室温下25°C 20min,然后低温保存60min。用电生理分析仪和超声波硬度计分别测定介电特性指标tanδm和心肌硬度ΔF,并计算Δtanδm和ΔΔF(Δtanδm定义为某一时刻的tanδm减去测定开始时的tanδm,ΔΔF定义为某一时刻的ΔF减去测定开始时的ΔF)。结果:对照组的tanδm逐渐减少,而实验组的tanδm在热缺血7min后出现一过性峰值,然后逐渐下降。实验组Δtanδm值高于对照组(P<0.001)。实验组ΔΔF值低于对照组(P<0.001)。结论:Δtanδm和ΔΔF之间有明显的相关关系。结果提示硬度指标可以用来评价无心跳心肌活性。同时也证明PGE1对心肌有保护作用。

Objective： We investigated the correlation between the dielectric properties and the myocardial tactile of non-beating heart graft during warm ischemia and cold preservation, and the effect of prostaglandin E1 （ PGE1 ） on these predictors of myocardial viability. Methods ： Following cardiac arrest induced by asphyxia, the cardiac graft was exposed to 20-minute warm ischemia and 60-minute cold preservation with and without the administration of PGE1. The tanδm and the myocardial tactile were measured using an impedance analyzer and a tactile sensor system, respectively. Results：Tanδm of the heart graft without PGE1 reduced gradationally. However, that of the heart graft with PGE1 showed the gradational reduction with the peak at 7 minutes after initiation of warm ischemia. △tanδm was subtracted the value at the initiation of warm ischemia from that of specific tanδm. △tanδm with PGE1 was higher than that without PGE1 （P 〈0.001 ）. △△F was subtracted the value at the initiation of warm ischemia from that of specific △F. △△F with PGE1 was lower than that without PGE1 （P 〈0. 001 ）. There was significant correlation between △tanδm and △△F. Conclusion： Myocardial tactile could represent the viability of non-beating heart graft, and PGE1 could preserve the myocardial viability.