Campos Carlos M, Fedewa Russell J, Garcia-Garcia Hector M, Vince D Geoffrey, Margolis M Pauliina, Lemos Pedro A, Stone Gregg W, Serruys Patrick W, Nair Anuja
Department of Interventional Cardiology, Erasmus University Medical Centre, Rotterdam, The Netherlands Department of Interventional Cardiology Heart Institute (InCor), University of São Paulo Medical School, Sao Paulo, Brazil.
Department of Biomedical Engineering, Cleveland Clinic Foundation, Cleveland, OH, USA.
Eur Heart J Cardiovasc Imaging. 2015 Oct;16(10):1112-9. doi: 10.1093/ehjci/jev039. Epub 2015 Mar 1.
The objectives of the present study are to describe the algorithm for VH(®) IVUS using the 45-MHz rotational IVUS catheter and the associated ex vivo validation in comparison to the gold standard histology.
The first phase of the present study was to construct the 45 MHz VH IVUS algorithm by using a total of 55 human coronary artery specimens [111 independent coronary lesions and 510 homogenous regions of interest (ROIs)], obtained at autopsy. Regions were selected from histology and matched with their corresponding IVUS data to build the plaque classification system using spectral analysis and statistical random forests. In the second phase, the ex vivo validation of the VH IVUS algorithm assessed a total of 1060 ROIs (120 lesions from 60 coronary arteries) in comparison with histology. In an independent manner, two interventional cardiologists also classified a randomly selected subset of the ROIs for assessment of inter- and intra-observer reproducibility of VH IVUS image interpretation.When including all ROIs, the predictive accuracies were 90.8% for fibrous tissue, 85.8% for fibro fatty tissue, 88.3% for necrotic core, and 88.0% for dense calcium. The exclusion of ROIs in the acoustically attenuated areas improved the predictive accuracies, ranging from 91.9 to 96.8%. The independent analysis of randomly selected 253 ROIs showed substantial agreement for inter-observer (k = 0.66) and intra-observer (k = 0.88) reproducibility.
Tissue classification by 45 MHz VH IVUS technology, when not influenced by calcium-induced acoustic attenuation, provided combined tissue accuracy >88% to identify tissue types compared with the gold standard histologic assessment, with high inter- and intra-observer reproducibility.
本研究的目的是描述使用45MHz旋转式血管内超声（IVUS）导管的VH（®）IVUS算法，以及与金标准组织学相比的相关离体验证。
本研究的第一阶段是通过使用总共55个人类冠状动脉标本[111个独立的冠状动脉病变和510个同质感兴趣区域（ROI）]构建45MHz VH IVUS算法，这些标本是在尸检时获得的。从组织学中选择区域，并将其与相应的IVUS数据匹配，以使用光谱分析和统计随机森林构建斑块分类系统。在第二阶段，VH IVUS算法的离体验证与组织学相比，共评估了1060个ROI（来自60条冠状动脉的120个病变）。另外，两名介入心脏病专家还以独立的方式对随机选择的ROI子集进行分类，以评估VH IVUS图像解释的观察者间和观察者内的可重复性。当纳入所有ROI时，纤维组织的预测准确率为90.8%，纤维脂肪组织为85.8%，坏死核心为88.3%，致密钙为88.0%。排除声学衰减区域中的ROI提高了预测准确率，范围从91.9%到96.8%。对随机选择的253个ROI的独立分析显示，观察者间（k = 0.66）和观察者内（k = 0.88）的可重复性具有高度一致性。
与金标准组织学评估相比，45MHz VH IVUS技术进行的组织分类在不受钙诱导的声学衰减影响时，识别组织类型的联合组织准确率>88%，具有较高的观察者间和观察者内可重复性。
