Clements I P, Christian T F, Higano S T, Gibbons R J, Gersh B J
Division of Cardiovascular Diseases and Internal Medicine, Mayo Clinic and Foundation, Rochester, Minn. 55905.
Circulation. 1993 Oct;88(4 Pt 1):1527-33. doi: 10.1161/01.cir.88.4.1527.
In acute myocardial infarction, residual flow to the infarct zone either through antegrade flow in the infarct-related coronary artery or collateral flow from the non-infarct-related arteries is often present before reperfusion therapy. The purpose of this study was to assess the influence of antegrade flow in the infarct-related artery and/or collateral flow to the infarct zone before successful direct angioplasty on infarct size and myocardial salvage in patients with acute evolving myocardial infarction.
Sixty patients with acute evolving myocardial infarction underwent direct successful angioplasty without prior thrombolytic therapy. The myocardium at risk of infarction, the final infarct size, and myocardial salvage were measured by tomographic perfusion imaging with 99mTc sestamibi. Antegrade flow in the infarct-related artery before intervention was graded according to the Thrombolysis in Myocardial Infarction (TIMI) study group classification. Collateral flow to the infarct zone before angioplasty was also graded (0 through 3, 0 being no collateral flow). The presence of even minimal antegrade flow before angioplasty (TIMI grade 1) in the infarct-related artery compared with absent flow was associated with a significant reduction in final infarct size (9 +/- 17% versus 23 +/- 19% of left ventricle, P = .02) and a significant increase in myocardial salvage (23 +/- 16% versus 14 +/- 13% of left ventricle, P = .05) after angioplasty. When antegrade flow in the infarct-related artery was absent before angioplasty, the presence of collateral flow before angioplasty resulted in a significantly smaller final infarct size (P = .01) and more myocardial salvage (P = .05) after angioplasty. Both antegrade infarct-related artery flow and collateral flow to the infarct zone had significant independent ability to predict infarct size after angioplasty. When collateral grade and TIMI grade were added to provide an estimate of residual flow, a model including residual flow, myocardium at risk, and the interaction of residual flow and infarct site explained 83% of the variability in infarct size after angioplasty.
The presence of antegrade flow in the infarct-related artery and/or collateral flow to the infarct zone before direct angioplasty in acute evolving infarction results in a smaller infarct size after direct successful angioplasty.
在急性心肌梗死中，在再灌注治疗前，梗死区域通常存在通过梗死相关冠状动脉的前向血流或来自非梗死相关动脉的侧支血流。本研究的目的是评估急性进展性心肌梗死患者在成功进行直接血管成形术之前，梗死相关动脉的前向血流和/或梗死区域的侧支血流对梗死面积和心肌挽救的影响。
60例急性进展性心肌梗死患者在未进行过溶栓治疗的情况下接受了直接成功的血管成形术。采用99mTc-甲氧基异丁基异腈断层灌注成像测量梗死危险心肌、最终梗死面积和心肌挽救情况。干预前梗死相关动脉的前向血流根据心肌梗死溶栓（TIMI）研究组分类进行分级。血管成形术前梗死区域的侧支血流也进行分级（0至3级，0级表示无侧支血流）。与无血流相比，血管成形术前梗死相关动脉中即使存在最小的前向血流（TIMI 1级）与最终梗死面积显著减小（左心室的9±17%对23±19%，P = 0.02）以及血管成形术后心肌挽救显著增加（左心室的23±16%对14±13%，P = 0.05）相关。当血管成形术前梗死相关动脉无前向血流时，血管成形术前存在侧支血流导致血管成形术后最终梗死面积显著减小（P = 0.01）和更多的心肌挽救（P = 0.05）。梗死相关动脉的前向血流和梗死区域的侧支血流都具有显著的独立能力来预测血管成形术后的梗死面积。当加入侧支分级和TIMI分级以评估残余血流时，一个包括残余血流、梗死危险心肌以及残余血流与梗死部位相互作用的模型解释了血管成形术后梗死面积变异性的83%。
急性进展性梗死患者在直接血管成形术之前，梗死相关动脉的前向血流和/或梗死区域的侧支血流的存在导致直接成功血管成形术后梗死面积较小。
