Finn Aloke V, Joner Michael, Nakazawa Gaku, Kolodgie Frank, Newell John, John Mike C, Gold Herman K, Virmani Renu
Cardiac Unit, Department of Internal Medicine, Massachusetts General Hospital, Boston, USA.
Circulation. 2007 May 8;115(18):2435-41. doi: 10.1161/CIRCULATIONAHA.107.693739. Epub 2007 Apr 16.
Late stent thrombosis (LST) after Cypher and Taxus drug-eluting stent placement has emerged as a major concern. Although the clinical predictors of LST have been reported, specific morphological and histological correlates of LST remain unknown.
From a registry totaling 81 human autopsies of drug-eluting stents, 46 (62 lesions) had a drug-eluting stent implanted >30 days. We identified 28 lesions with thrombus and compared those with 34 of similar duration without thrombosis using computer-guided morphometric and histological analyses. LST was defined as an acute thrombus within a coronary artery stent in place >30 days. Multiple logistic generalized estimating equations modeling demonstrated that endothelialization was the best predictor of thrombosis. The morphometric parameter that best correlated with endothelialization was the ratio of uncovered to total stent struts per section. A univariable logistic generalized estimating equations model of occurrence of thrombus in a stent section versus ratio of uncovered to total stent struts per section demonstrated a marked increase in risk for LST as the number of uncovered struts increased. The odds ratio for thrombus in a stent with a ratio of uncovered to total stent struts per section >30% is 9.0 (95% CI, 3.5 to 22).
The most powerful histological predictor of stent thrombosis was endothelial coverage. The best morphometric predictor of LST was the ratio of uncovered to total stent struts. Heterogeneity of healing is a common finding in drug-eluting stents with evidence of LST and demonstrates the importance of incomplete healing of the stented segment in the pathophysiology of LST.
西罗莫司和紫杉醇药物洗脱支架置入术后的晚期支架内血栓形成（LST）已成为一个主要问题。尽管已有LST的临床预测因素报道，但LST具体的形态学和组织学关联仍不清楚。
在一项总计81例药物洗脱支架人体尸检的登记研究中，46例（62个病变）植入药物洗脱支架超过30天。我们识别出28个有血栓的病变，并使用计算机辅助形态测量和组织学分析将其与34个持续时间相似但无血栓形成的病变进行比较。LST定义为冠状动脉支架内植入30天以上的急性血栓。多因素逻辑广义估计方程模型显示，内皮化是血栓形成的最佳预测因素。与内皮化最相关的形态学参数是每切片未覆盖支架支柱与总支架支柱的比例。支架切片内血栓形成与每切片未覆盖支架支柱与总支架支柱比例的单因素逻辑广义估计方程模型显示，随着未覆盖支柱数量增加，LST风险显著增加。每切片未覆盖支架支柱与总支架支柱比例>30%的支架内血栓形成的比值比为9.0（95%CI，3.5至22）。
支架内血栓形成最有力的组织学预测因素是内皮覆盖。LST最佳的形态学预测因素是未覆盖支架支柱与总支架支柱的比例。愈合异质性是LST证据的药物洗脱支架中的常见发现，表明支架段愈合不完全在LST病理生理学中的重要性。
