Chung-Ang University Hospital, Seoul, Korea.
Am J Cardiol. 2012 Mar 15;109(6):794-9. doi: 10.1016/j.amjcard.2011.10.042. Epub 2011 Dec 21.
We used virtual histology intravascular ultrasound (VH-IVUS) to assess culprit plaque rupture in 172 patients with ST-segment elevation acute myocardial infarction. VH-IVUS-defined thin-capped fibroatheroma (VH-TCFA) had necrotic core (NC) > 10% of plaque area, plaque burden > 40%, and NC in contact with the lumen for ≥ 3 image slices. Ruptured plaques were present in 72 patients, 61% of which were located in the proximal 30 mm of a coronary artery. Thirty-five were classified as VH-TCFA and 37 as non-VH-TCFA. Vessel size, lesion length, plaque burden, minimal lumen area, and frequency of positive remodeling were similar in VH-TCFA and non-VH-TCFA. However, the NC areas within the rupture sites of VH-TCFAs were larger compared to non-VH-TCFAs (p = 0.002), while fibrofatty plaque areas were larger in non-VH-TCFAs (p < 0.0001). Ruptured plaque cavity size was correlated with distal reference lumen area (r = 0.521, p = 0.00002), minimum lumen area (r = 0.595, p < 0.0001), and plaque area (r = 0.267, p = 0.033). Sensitivity and specificity curve analysis showed that a minimum lumen area of 3.5 mm2, a distal reference lumen area of 7.5 mm2, and a maximum NC area of 35% best predicted plaque rupture. Although VH-TCFA (35 of 72) was the most frequent phenotype of plaque rupture in ST-segment elevation myocardial infarction, plaque rupture also occurred in non-VH-TCFA: pathologic intimal thickening (8 of 72), thick-capped fibroatheroma (1 of 72), and fibrotic (14 of 72) and fibrocalcified (14 of 72) plaque. In conclusion, not all culprit plaque ruptures in patients with ST-segment elevation myocardial infarction occur as a result of TCFA rupture; a prominent fibrofatty plaque, especially in a proximal vessel, may be another form of vulnerable plaque. Further study should identify additional factors causing plaque rupture.
我们使用虚拟组织学血管内超声（VH-IVUS）评估了 172 例 ST 段抬高型急性心肌梗死患者的罪犯斑块破裂情况。VH-IVUS 定义的薄帽纤维粥样瘤（VH-TCFA）的坏死核心（NC）占斑块面积的>10%，斑块负荷>40%，NC 与管腔接触的图像切片数≥3 个。72 例患者存在破裂斑块，其中 61%位于冠状动脉近端 30mm 内。35 例被分类为 VH-TCFA，37 例为非 VH-TCFA。VH-TCFA 和非 VH-TCFA 的血管大小、病变长度、斑块负荷、最小管腔面积和正性重构的频率相似。然而，VH-TCFA 破裂部位的 NC 面积大于非 VH-TCFA（p=0.002），而非 VH-TCFA 的纤维脂肪斑块面积较大（p<0.0001）。破裂斑块腔大小与远端参考管腔面积（r=0.521，p=0.00002）、最小管腔面积（r=0.595，p<0.0001）和斑块面积（r=0.267，p=0.033）相关。敏感性和特异性曲线分析表明，最小管腔面积 3.5mm2、远端参考管腔面积 7.5mm2 和最大 NC 面积 35% 可最佳预测斑块破裂。尽管 VH-TCFA（72 例中有 35 例）是 ST 段抬高型心肌梗死中最常见的斑块破裂表型，但非 VH-TCFA 也会发生斑块破裂：病理性内膜增厚（72 例中有 8 例）、厚帽纤维粥样瘤（72 例中有 1 例）、纤维性（72 例中有 14 例）和纤维钙化性（72 例中有 14 例）斑块。总之，并非所有 ST 段抬高型心肌梗死患者的罪犯斑块破裂都是 TCFA 破裂所致；突出的纤维脂肪斑块，特别是在近端血管中，可能是另一种易损斑块。进一步的研究应确定导致斑块破裂的其他因素。
