Porto Italo, Selvanayagam Joseph B, Van Gaal William J, Prati Francesco, Cheng Adrian, Channon Keith, Neubauer Stefan, Banning Adrian P
Department of Cardiology, John Radcliffe Hospital, Oxford, OX3 9DU, UK.
Circulation. 2006 Aug 15;114(7):662-9. doi: 10.1161/CIRCULATIONAHA.105.593210. Epub 2006 Aug 7.
Myocardial necrosis can occur during percutaneous coronary intervention (PCI) despite optimal adjunctive pharmacology and careful technique. We investigated the mechanisms of procedural infarction using angiographic analysis, intravascular ultrasound, and delayed-enhancement magnetic resonance imaging.
Fifty-two patients (64 vessels) who underwent complex PCI were studied. All patients were preloaded with clopidogrel and received glycoprotein IIb/IIIa inhibitors. "Adjacent" myonecrosis was defined as the presence of an area of new gadolinium hyperenhancement close to the stent. "Distal" myonecrosis was defined as situated at least 10 mm downstream from the stent. Fifteen vessels (23%) had evidence of new hyperenhancement after PCI. Of these, 8 (12%) had the distal type, and 7 (11%) had the adjacent type. Intravascular ultrasound showed a significantly greater reduction in plaque volume (91.6+/-51.5 versus 8+/-14 versus 20+/-35 mm3; P < 0.001) in the group with distal hyperenhancement compared with patients without new hyperenhancement or adjacent hyperenhancement. In the entire sample, a significant correlation was seen between changes in plaque volume (rho = 0.58, P < 0.001) after PCI and the mass of new necrosis measured by magnetic resonance imaging. Thrombolysis in Myocardial Infarction perfusion grade assessment of a closed microvasculature after PCI carried an odds ratio of 8.0 (95% confidence interval, 1.4 to 46.1; P = 0.02) for the occurrence of hyperenhancement, whereas side-branch occlusion was associated with an odds ratio of 16.2 (95% confidence interval, 2.6 to 102.5; P = 0.03). However, a closed microvasculature was associated with distal hyperenhancement (P = 0.02), and side-branch occlusion was associated with adjacent hyperenhancement (P < 0.001).
These data suggest that distal embolization of plaque material occurs in contemporary PCI of native coronary arteries. Efforts to minimize procedural necrosis may require careful review of side branch anatomy and/or use of distal protection during extensive coronary stenting.
尽管采用了最佳的辅助药物治疗并谨慎操作技术，但经皮冠状动脉介入治疗（PCI）过程中仍可能发生心肌坏死。我们使用血管造影分析、血管内超声和延迟强化磁共振成像研究了手术梗死的机制。
对52例（64支血管）接受复杂PCI的患者进行了研究。所有患者均预先服用氯吡格雷并接受糖蛋白IIb/IIIa抑制剂治疗。“相邻”心肌坏死定义为靠近支架处存在新的钆增强区域。“远端”心肌坏死定义为位于支架下游至少10毫米处。15支血管（23%）在PCI后有新的增强证据。其中，8支（12%）为远端型，7支（11%）为相邻型。血管内超声显示，与无新增强或相邻增强的患者相比，远端增强组的斑块体积显著减小（91.6±51.5对8±14对20±35立方毫米；P<0.001）。在整个样本中，PCI后斑块体积变化（rho=0.58，P<0.001）与磁共振成像测量的新坏死质量之间存在显著相关性。PCI后闭塞微血管的心肌梗死溶栓灌注分级评估显示，发生增强的比值比为8.0（95%置信区间，1.4至46.1；P=0.02），而侧支闭塞的比值比为16.2（95%置信区间，2.6至102.5；P=0.03）。然而，闭塞微血管与远端增强相关（P=0.02），侧支闭塞与相邻增强相关（P<0.001）。
这些数据表明，在当代天然冠状动脉PCI中会发生斑块物质的远端栓塞。尽量减少手术坏死的努力可能需要仔细评估侧支解剖结构和/或在广泛冠状动脉支架置入过程中使用远端保护装置。
