Ghaleh B, Shen Y T, Vatner S F
Department of Medicine, Harvard Medical School, Brigham & Women's Hospital, Boston, Mass, USA.
Circulation. 1996 Nov 1;94(9):2210-5. doi: 10.1161/01.cir.94.9.2210.
Myocardial blood flow distribution is known to be heterogeneous. It is also known that not all of the area at risk (AAR) infarcts with coronary artery occlusion (CAO) and coronary artery reperfusion (CAR). The goal of the present study was to determine whether the proportion of AAR that is salvaged or infarcted can be predicted by the pre-CAO level of myocardial blood flow, which varies considerably in individual samples as a result of natural heterogeneity.
The effects of 90-minute CAO followed by 5- to 7-day CAR were examined in six conscious baboons instrumented with aortic and left atrial catheters and coronary artery occluders. AAR was determined by dual perfusion. Myocardial blood flow was measured by radioactive microspheres before and after CAO and CAR. The AAR was cut into small pieces (0.21 +/- 0.01 g) and separated into two categories; salvaged (n = 252) or infarcted (n = 133). Analysis of myocardial blood flow distribution revealed two distinct populations (P < .01); infarcted tissues demonstrated higher pre-CAO myocardial blood flow than salvaged tissues. Importantly, 50% of the salvaged tissue samples were characterized by pre-CAO myocardial blood flows of < 0.90 mL.min-1.g-1 compared with 29% for infarcted samples, whereas 51% of infarcted samples were characterized by pre-CAO myocardial blood flows of > 1.12 mL.min-1.g-1 compared with 22% of salvaged samples. Endocardial analyses were qualitatively similar to transmural analyses.
This study suggests that heterogeneity of pre-CAO myocardial blood flows can predict the proportion of myocardium salvaged by CAR and can further explain the spatial heterogeneity of infarction that occurs after CAR, potentially independent of CAR injury.
已知心肌血流分布是不均匀的。也已知并非所有的危险区域（AAR）在冠状动脉闭塞（CAO）和冠状动脉再灌注（CAR）时都会梗死。本研究的目的是确定能否通过CAO前的心肌血流水平来预测挽救或梗死的AAR比例，由于自然的不均匀性，个体样本中的心肌血流水平差异很大。
在6只植入主动脉和左心房导管以及冠状动脉闭塞器的清醒狒狒中，研究了90分钟CAO后接着5至7天CAR的效果。通过双重灌注确定AAR。在CAO和CAR前后，用放射性微球测量心肌血流。将AAR切成小块（0.21±0.01克）并分为两类：挽救的（n = 252）或梗死的（n = 133）。心肌血流分布分析显示出两个不同的群体（P <.01）；梗死组织在CAO前的心肌血流高于挽救组织。重要的是，50%的挽救组织样本在CAO前的心肌血流<0.90 mL·min-1·g-1，而梗死样本为29%，而51%的梗死样本在CAO前的心肌血流>1.12 mL·min-1·g-1，挽救样本为22%。心内膜分析在质量上与透壁分析相似。
本研究表明，CAO前心肌血流的不均匀性可以预测CAR挽救的心肌比例，并可以进一步解释CAR后发生的梗死的空间不均匀性，这可能独立于CAR损伤。
