Department of Cardiovascular Medicine, Toyohashi Heart Center, Aichi, Japan.
Department of Cardiovascular Medicine, National Cerebral and Cardiovascular Center, Osaka, Japan.
Int J Cardiol. 2018 Oct 1;268:1-10. doi: 10.1016/j.ijcard.2018.05.022. Epub 2018 May 10.
The histopathological validation of optical coherence tomography (OCT) in visualizing atherosclerotic plaques has been reported only in ex vivo studies. We sought to evaluate the accuracy of OCT in tissue characterization in vivo.
A total of 25 patients with stable angina pectoris who underwent directional coronary atherectomy (DCA) were included in the investigation, whereby OCT was performed before and after a single debulking. The debulked region was determined on OCT and classified into fibrous tissue, lipid, calcification, thrombus, and macrophage accumulation, which were compared with histology. Changes in OCT signal intensity in the deeper intimal region after DCA were also visually evaluated. Fibrous tissues were detected in all cases, while thrombus was identified only in 1 case, by both OCT and histology. The sensitivity, specificity, positive and negative predictive values, and predictive accuracy for lipid detection by OCT were 88.9%, 75.0%, 66.7%, 92.3%, and 80.0%; those for calcification were 50.0%, 100%, 100%, 91.3%, and 92.0%; and those for macrophage accumulation were 85.7%, 88.9%, 75.0%, 94.1%, and 88.0%, respectively. The false positive diagnoses for lipid were mostly attributed to the extracellular matrix accumulation containing less collagen. The false negative diagnoses for calcification were explained by the presence of lipid around the calcification. The OCT signal intensity in the deeper intimal region substantially increased after DCA in all cases.
The current study showed excellent predictive accuracy of in vivo OCT in tissue characterization, whereas the limitations of OCT were highlighted by an over-detection of lipid, under-detection of calcification, and underestimation of the deeper intimal matrix.
光学相干断层扫描（OCT）在可视化动脉粥样硬化斑块方面的组织学验证仅在离体研究中得到报道。我们旨在评估 OCT 在体内组织特征描述中的准确性。
共纳入 25 例稳定性心绞痛患者，均行定向冠状动脉斑块切除术（DCA），在单次斑块切除前后行 OCT 检查。根据 OCT 结果对斑块切除区进行分类，分为纤维组织、脂质、钙化、血栓和巨噬细胞聚集，并与组织学进行比较。此外，还对 DCA 后深层内膜区 OCT 信号强度的变化进行了直观评估。所有病例均在 OCT 和组织学上发现了纤维组织，而仅在 1 例中发现了血栓。OCT 检测脂质的敏感性、特异性、阳性预测值、阴性预测值和预测准确率分别为 88.9%、75.0%、66.7%、92.3%和 80.0%；检测钙化的敏感性、特异性、阳性预测值、阴性预测值和预测准确率分别为 50.0%、100%、100%、91.3%和 92.0%；检测巨噬细胞聚集的敏感性、特异性、阳性预测值、阴性预测值和预测准确率分别为 85.7%、88.9%、75.0%、94.1%和 88.0%。脂质的假阳性诊断主要归因于富含较少胶原蛋白的细胞外基质的积累。钙化的假阴性诊断可由钙化周围的脂质存在来解释。所有病例在 DCA 后深层内膜区的 OCT 信号强度均显著增加。
本研究表明，OCT 在体内组织特征描述方面具有优异的预测准确性，但其也存在局限性，包括脂质的过度检测、钙化的漏诊以及对深层内膜基质的低估。
