Effect of graded coronary flow reduction on ionic, electrical, and mechanical indexes of ischemia in the pig.
Effect of graded coronary flow reduction on ionic, electrical, and mechanical indexes of ischemia in the pig.
复制标题
分级冠脉流量减少对猪缺血离子、电和机械指标的影响。
DOI：
10.1161/01.cir.76.5.1127
复制
发表时间：
1987
期刊：
影响因子：
37.8
通讯作者：
Gettes,LS
中科院分区：
文献类型：
--
作者：
Watanabe,I;Johnson,TA;Buchanan,J;Engle,CL;Gettes,LS
本研究旨在确定心肌缺血的离子、电学和力学指标的相对敏感性。我们使用离子选择性和双极插入电极、心外膜单极电极、抽吸电极和超声晶体来确定开胸猪在分级冠状动脉血流减少期间心肌内细胞外钾（[K+]e）和细胞外pH（pHe）、局部激动、心外膜TQ-ST段、单相动作电位时程（MAPD）和局部收缩力的变化。建立颈动脉-冠状动脉分流术，通过滚子泵灌注左前降支冠状动脉。分流的冠状动脉流量以5分钟的间隔逐步减少。在25头猪中，与各变量初始变化相关的大致心肌血流量如下：中层心肌[K+]e、pHe和TQ-ST段0.7 ~ 0.8 ml/min/g，心外膜下[K+]e和TQ-ST段0.6 ~ 0.7 ml/min/g，节段缩短0.5 ~ 0.6 ml/min/g，心肌收缩0.5 ~ 0.6 ml/min/g，心肌收缩0.5 ~ 0.6 ml/min/g，心肌收缩0.5 ~ 0.6 ml/min/g。局部激动和心外膜TQ-ST段，0.3 ~ 0.4 ml/min/g;心外膜MAPD，0.15 ~ 0.2 ml/min/g。我们的研究结果表明，[K+]e，pHe和TQ-ST段的变化提供了最敏感的手段检测心肌缺血和确定干预措施的影响，能够影响缺血过程。
This study was performed to determine the relative sensitivities of ionic, electrical, and mechanical indexes of myocardial ischemia. We used ion-selective and bipolar plunge electrodes, epicardial unipolar electrodes, a suction electrode, and ultrasonic crystals to determine the changes in intramyocardial extracellular potassium ([K+]e) and extracellular pH (pHe), local activation, epicardial TQ-ST segment, monophasic action potential duration (MAPD), and regional contractility during graded coronary flow reduction in open-chest pigs. A carotid-to-coronary shunt was created to perfuse the left anterior descending coronary artery via a roller pump. The shunted coronary flow was reduced in a stepwise fashion at 5-min intervals. In 25 pigs, the approximate myocardial blood flow associated with the initial changes in each variable was as follows: midmyocardial [K+]e, pHe, and TQ-ST segment, 0.7 to 0.8 ml/min/g; subepicardial [K+]e and TQ-ST segment, 0.6 to 0.7 ml/min/g; segmental shortening, 0.5 to 0.6 ml/min/g; local activation and epicardial TQ-ST segment, 0.3 to 0.4 ml/min/g; epicardial MAPD, 0.15 to 0.2 ml/min/g. Our results indicate that changes in [K+]e, pHe, and TQ-ST segment provide the most sensitive means of detecting myocardial ischemia and of determining the effect of interventions capable of influencing the ischemic process.