Atherosclerotic plaque composition assessed by virtual histology intravascular ultrasound and cerebral embolization after carotid stenting
Atherosclerotic plaque composition assessed by virtual histology intravascular ultrasound and cerebral embolization after carotid stenting
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DOI：
10.1016/j.jvs.2010.05.101
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发表时间：
2010-11-01
影响因子：
4.3
通讯作者：
Clagett, G. Patrick
中科院分区：
文献类型：
--
作者：
Timaran, Carlos H.;Rosero, Eric B.;Clagett, G. Patrick
目的：先前的研究已经探讨了临床和形态参数在颈动脉介入治疗中远端栓塞术中的预测价值。动脉粥样硬化斑块的成分，使用虚拟组织学血管内超声(VH-IVUS)成像，通过IVUS导管在远端放置过滤器后穿过病变获得，尚未被评估为脑栓塞的标志。本研究的目的是评估VH-IVUS检测的动脉粥样硬化斑块成分与颈动脉支架置入术(CAS)后脑血栓形成的关系。方法：在10个月的时间里，对24例接受CAS手术的患者进行前瞻性评估。所有患者在干预时都接受了VH-IVUS检查，CAS期间的经颅多普勒(TCD)监测，以及术前和术后24小时的弥散加权磁共振成像(DW-MRI)检查。使用VH-IVUS，斑块成分的特征是纤维化、纤维脂肪、致密钙和坏死核。评估CAS期间多普勒检测到的微栓子信号(MES)的频率以及DW-MRI检测到的术后急性栓塞灶的发生率和部位，以确定是否进行了脑栓塞。结果：30天内无一例发生短暂性脑缺血发作、中风或死亡。17例患者(71%)在DW-MRI上发现新的急性脑血栓。在这些病例中，所有病例均为同侧病变，12例(50%)为对侧病变。在整个研究组中，同侧DW-MRI病变的中位数为1个(范围从0到3)，TCD MES计数为227个(四分位数范围从143到315)。VH-IVUS容积分析显示，DW-MRI发现同侧亚临床型脑梗塞患者的中位密度钙体积有增大的趋势(33.2±24.5 mm(3例)vs11.4±6.1 mm(3例)；P=0.08)。斑块成分散点图显示DW-MRI中纤维脂肪斑块体积(Spearman r=0.49；P=0.016)与新的同侧病变数目之间有统计学意义的相关性。颈动脉内支架置入术中，TCD测量的脑栓塞程度与斑块负荷、坏死灶、纤维脂肪和纤维体积相关。结论：VH-IVUS测定的斑块成分与颈动脉支架置入术后的脑栓塞程度只有微弱的相关性。具体地说，在接受远端栓塞术的患者中，有一种较大的致密钙量的趋势。值得注意的是，坏死核心的比例，传统上被认为是脆弱或不稳定斑块的主要成分，当使用滤器进行血栓保护时，与CAS术后亚临床脑栓塞并不一定相关。VH-IVUS在评估CAS期间斑块成分中的作用仍未确定，值得进一步研究。(《花瓶外科杂志》2010；52：1188-95。)
Objective: Previous studies have investigated the predictive value of clinical and morphologic parameters for distal embolization during carotid interventions. The composition of the atherosclerotic plaque, using virtual histology intravascular ultrasound (VH-IVUS) imaging obtained with an IVUS catheter that is advanced through the lesion after a filter has been placed distally, has not been evaluated as a marker for cerebral embolization. The purpose of this study was to assess the relationship between atherosclerotic plaque composition determined with VH-IVUS and the occurrence of cerebral embolization after carotid artery stenting (CAS).Methods: During a 10-month period, 24 patients undergoing CAS procedures using a filter device for embolic protection were prospectively evaluated. All patients underwent VH-IVUS exams at the time of the intervention, transcranial Doppler (TCD) monitoring during CAS, and pre- and 24-hour postprocedural diffusion-weighted magnetic resonance imaging (DW-MRI) exams. Using VH-IVUS, plaque components were characterized as fibrotic, fibrofatty, dense calcium, and necrotic core. The frequency of Doppler-detected microembolic signals (MES) during CAS and the incidence and location of acute postprocedural embolic lesions detected with DW-MRI were assessed to determine cerebral embolization. Univariate and correlation analyses were used to assess the association between plaque composition and frequency of cerebral embolization.Results: No periprocedural transient ischemic attacks, strokes, or deaths occurred within 30 days. Seventeen patients (71%) demonstrated new acute cerebral emboli in DW-MRI. Of these, all revealed ipsilateral lesions and 12 (50%) had contralateral lesions. For the entire study group, the median number of ipsilateral DW-MRI lesions was 1 (range, 0 to 3), and TCD MES counts were 227 (interquartile range, 143-315). Volumetric VH-IVUS analysis revealed that there was a trend for larger median dense calcium volume in patients with ipsilateral subclinical cerebral embolism detected with DW-MRI (33.2 +/- 24.5 mm(3) vs 11.4 +/- 6.1 mm(3); P = .08). Scatter plots of plaque components revealed statistically significant correlation between fibrofatty plaque volume (Spearman r = 0.49; P = .016) and number of new ipsilateral lesions in DW-MRI. Degree of cerebral embolization during CAS measured with TCD correlated with plaque burden, necrotic core, fibrofatty, and fibrous volumes.Conclusions: Plaque composition, as determined by VH-IVUS, only weakly correlates with the degree of cerebral embolization after carotid stenting. Specifically, there is a trend for larger dense calcium volume in patients with distal embolization. Of note, the proportion of necrotic core, which has traditionally been considered the main component of a vulnerable or unstable plaque, is not definitely associated with subclinical cerebral embolization after CAS when a filter device for embolic protection is used. The role of VH-IVUS in evaluating plaque composition during CAS remains unestablished and warrants further investigation. (J Vase Surg 2010;52:1188-95.)