Nonuniform loss of regional flow reserve during myocardial ischemia in dogs.
Nonuniform loss of regional flow reserve during myocardial ischemia in dogs.
复制标题
犬心肌缺血期间局部血流储备的不均匀损失。
DOI：
10.1161/01.res.67.2.253
复制
发表时间：
1990
影响因子：
20.1
通讯作者：
Hoffman,JI
中科院分区：
文献类型：
--
作者：
Coggins,DL;Flynn,AE;AustinJr,RE;Aldea,GS;Muehrcke,D;Goto,M;Hoffman,JI
为了确定在心肌缺血期间持续存在的冠状动脉血管扩张储备是否存在于所有左心室区域，我们通过使用放射性微球在70、50、40和30 mm Hg下灌注左主冠状动脉时测量了8只犬中每只犬192个左心室片（平均重量，201 mg）的局部血流量。在腺苷输注之前和期间测量流量以确定流量储备。在40和30毫米汞柱灌注产生缺血在所有的狗。在70 mm Hg时，100%的左心室区域具有显著的血流储备，而在50、40和30 mm Hg灌注时分别为92%、55%和8%。在50、40和30 mm Hg时，心外膜下比心内膜下有更大量的血流储备和更多的区域对腺苷产生反应。我们的结论是，冠状动脉血流储备持续在缺血期间，只有一个子集的左心室区域和持续血流储备的区域数量与灌注压下降。这些发现可能是最好的解释模型中，局部缺血是一个最大的冠状动脉血管扩张剂和持续的药理学血管扩张储备时，全球标记物表明缺血只是反映了持续的内源性血流储备心肌地区尚未缺血。
To determine whether coronary vasodilator reserve that persists during myocardial ischemia is present in all left ventricular regions, we measured regional blood flow in 192 left ventricular pieces (mean weight, 201 mg) in each of eight dogs by using radioactive microspheres while perfusing the left main coronary artery at 70, 50, 40, and 30 mm Hg. Flows were measured before and during adenosine infusion to determine flow reserve. Perfusion at 40 and 30 mm Hg produced ischemia in all dogs. At 70 mm Hg, 100% of left ventricular regions had significant flow reserve, compared with 92%, 55%, and 8% during perfusion at 50, 40, and 30 mm Hg, respectively. A greater amount of flow reserve and a greater number of regions responded to adenosine in the subepicardium than in the subendocardium at 50, 40, and 30 mm Hg. We conclude that coronary flow reserve persists in only a subset of left ventricular regions during ischemia and that the number of regions with persistent flow reserve decreases with perfusion pressure. These findings may best be explained by a model in which regional ischemia is a maximal coronary vasodilator and persistent pharmacological vasodilator reserve seen when global markers indicate ischemia simply reflects persistent endogenous flow reserve in myocardial regions not yet ischemic.