Role of myocardial perfusion imaging in evaluating thrombolytic therapy for acute myocardial infarction.
Role of myocardial perfusion imaging in evaluating thrombolytic therapy for acute myocardial infarction.
复制标题
心肌灌注成像在评估急性心肌梗死溶栓治疗中的作用。
DOI：
10.1016/s0735-1097(87)80062-1
复制
发表时间：
1987
影响因子：
24
通讯作者：
Beller,GA
中科院分区：
文献类型：
--
作者：
Beller,GA
铊-201心肌显像正日益被用作评价急性心肌梗死冠状动脉再灌注疗效的方法。成功再通后冠状动脉内示踪剂给药后新的铊摄取表明营养性血流已成功恢复。如果以这种方式给药的铊由具有完整肌膜的肌细胞在细胞内转运，也可以推测发生了一些心肌挽救。然而，如果再灌注后立即通过冠状动脉内途径注射铊，则再灌注心肌中铊的初始摄取可能主要代表充血流量，并且测量的区域铊计数可能与存活肌细胞的质量不成比例。当在闭塞期静脉注射铊时，溶栓后再分布的程度与血流恢复和心肌存活的程度成正比。当再灌注后立即首次静脉注射铊时，由于梗塞区明显充血后铊摄取“过量”，可能会高估心肌细胞的挽救作用。在接受溶栓治疗的患者中进行心肌铊造影的另一种方法是在治疗前和治疗后24小时或更晚进行两次单独的静脉注射。临床研究表明，连续图像上缺陷尺寸的改善预示着梗死相关血管的局部功能和通畅性的改善。最后，接受静脉溶栓治疗的急性心肌梗死患者是出院前运动铊-201闪烁扫描的候选人，用于风险分层和残余缺血检测。在梗死相关血管区或梗死区域内或远离梗死区域的多处缺损中显示铊再分布的患者将是血运重建的候选者，以降低随后缺血事件的发生率。
Myocardial thallium-201 scintigraphy is being increasingly employed as a method for assessing the efficacy of coronary reperfusion in acute myocardial infarction. New thallium uptake after intracoronary tracer administration after successful recanalization indicates that nutrient blood flow has been successfully restored, One may also presume that some myocardial salvage occurred if thallium administered in this manner is transported intracellularly by myocytes with intact sarcolemmal membranes. However, if one injects thallium by way of the intracoronary route immediately after reperfusion, the initial uptake of thallium in reperfused myocardium may predominantly represent hyperemic flow and regional thallium counts measured may not be proportional to the mass of viable myocytes. When thallium is injected intravenously during the occlusion phase the degree of redistribution after thrombolysis is proportional to the degree of flow restoration and myocardial viability. When thallium is injected for the first time intravenously immediately after reperfusion, an overestimation of myo- cardial salvage may occur because of “excess” thallium uptake in the infarct zone consequent to significant hyperemia. Another approach to myocardial thallium scintigraphy in patients undergoing thrombolytic therapy is to administer two separate intravenous injections before and 24 hours or later after treatment. Clinical studies have demonstrated that the improvement in defect size on serial images predicts improvement in regional function and patency of the infarct-related vessel.Finally, patients with acute myocardial infarction who receive intravenous thrombolytic therapy are candidates for predischarge exercise thallium-201 scintigraphy for risk stratification and detection of residual ischemia. Patients demonstrating thallium redistribution in the zone of the infarct-related vessel or multiple defects within or remote from the infarct region would be candidates for revascularization to reduce the incidence of subsequent ischemic events.