复流后高灌注心表冠脉血流与心肌微循环血流不匹配现象的实验研究  

Discrepancy between the blood flow in hyperperfused epicardial coronary vessels and myocardial microcirculation following reperfusion:a study in canines

作　　者：冯金华[1] 区文超[1] 刘俭[1] 宾建平[1] 查道刚[1] 刘伊丽[1] 

机构地区：[1]第一军医大学南方医院心内科,广州广东510515

出　　处：《第一军医大学学报》2003年第6期591-594,共4页Journal of First Military Medical University

基　　金：军队"九五"课题分支项目(98Z072)~~

摘　　要：目的探讨短时间(2 min)冠脉缺血再灌注后反应性充血期心表冠脉血流与心肌微循环血流的动力学改变。方法12只成龄杂种犬开胸分离冠脉,环扎前降支第一间隔支以下部位2次,每次2 min,分别观察并记录缺血前后及再灌注后心率、收缩压、舒张压、平均压和再灌注后5、10、15、30、45、60、90和120 s时的心表冠脉血流和相应区域的心肌微循环血流。Doppler超声冠脉血流仪测心表冠脉血流,心肌声学造影测心肌微循环血流。结果反应性充血期心表冠脉血流和心肌微循环血流均有高灌注反应,但两者的动力学改变不同,表现出血流动态不一致即血流不匹配现象,并且心表冠脉血流的峰值血流明显高于心肌微循环血流。结论心肌短时间的缺血再灌注后会出现反应性充血期,这期间心表冠脉血流与心肌微循环血流发生不匹配现象,主要机制可能是毛细血管的征募和通血毛细血管的开放,对心肌的影响主要是增加心肌灌注,同时也使冠脉微循环的储备降低。Objective To investigate the hemodynamic changes in the epicardial coronary blood flow (ECBF) and myocardial microcirculation (MMC) during reactive hyperemia (RH) in response to reperfusion following 2-min ischemia in the left anterior descending coronary artery of canines. Methods Twelve adult mongrel dogs were used, whose left anterior descending coronary artery was separated and ligated for 2 min twice below the first branch. The heart rate, systolic blood pressure, diastolic blood pressure, mean blood pressure, ECBF and MMC were measured respectively before and after the ligation and at 5, 10, 15, 30, 45, 60, 90 and 120 s after reperfusion. ECBF was determined with Doppler coronary flowmeter and MMC derived from the ultrasonic intensity measured by myocardial contrast echocardiography. Results During the course of RH, ECBF and MMC both evinced responses to hyperperfusion but in manners different in view of their hemodynaminc changes, demonstrating the mismatch between them in this condition. ECBF exhibited a much higher peak flow increase than MMC. Conclusions RH occurs in response to reperfusion after short-term (2 min) myocardial ischemia, when the discrepancy arises between ECBF and MMC. The primary mechanism might involve the recruitment of the capillaries and the opening of the shunt through the capillaries, and as a consequence, the myocardial perfusion is increased at the cost of decreased reserve of the coronary microcirculation.

关 键 词：反应性充血 再灌注 冠脉血流 心肌微循环 血流动力学 

分 类 号：R541[医药卫生—心血管疾病]