Department of Cardiology, Union Hospital, Fujian Medical University, and Fujian Institute of Coronary Artery Disease, Fuzhou 350001, P. R. China.
Exp Biol Med (Maywood). 2013 Nov 1;238(11):1223-32. doi: 10.1177/1535370213493704. Epub 2013 Oct 1.
This study aimed to evaluate the utility of virtual histology intravascular ultrasound (VH-IVUS) for recognizing vulnerable plaque compared to histological pathological analysis. Four-month-old New Zealand rabbits (n = 16) were randomly divided into two groups: one fed a high-fat diet and subjected to balloon injury (experimental, n = 10) and one fed a high-fat diet alone (control, n = 6). Blood lipid profiles of overnight-fasted rabbits were measured at week 2 (beginning of study) and week 12 (end of study). At week 12, experimental group rabbits underwent IVUS under anaesthesia. Rabbits were sacrificed and a 5-cm segment of the abdominal aorta was removed. Arterial sections were subjected to pathological and immunohistochemical analyses. Serum lipid levels increased in all rabbits fed with high-fat diet, with low-density lipid cholesterol (LDL-C) levels increasing the most. Levels of six biomarkers (high sensitivity C-reactive protein, matrix metalloproteinase-3, interleukin [IL]-1, IL-10, tumour necrosis factor-α, and oxidized [ox]-LDL) showed no differences between the two groups at week 2, but were higher in the experimental group at week 12. A total of 276 atherosclerotic plaques in the experimental group were analysed. VH-IVUS had sensitivities of 87% and 92% for detection of noncalcified and calcified thin-cap fibroatheromas, respectively. VH-IVUS correctly identified 85% and 89% of noncalcified and calcified fibroatheromas, respectively. For detection of pathological intimal thickening, VH-IVUS showed a sensitivity of 79% and positive predictive value of 78%. Linear regression analysis showed a strong correlation between histology and VH-IVUS for the percent area of fibrous fibro-fatty tissue, necrotic calcified tissue, and confluent necrotic core. The intra-observer and inter-observer variability of the intimal and medial-adventitial boundaries was low. Endothelial injury followed by a high-fat diet in rabbits is a viable method for inducing atheroma, and VH-IVUS is a feasible, reproducible, and valuable means of vulnerable plaque identification in vivo.
本研究旨在评估虚拟组织学血管内超声（VH-IVUS）与组织病理学分析相比，在识别易损斑块方面的效用。将 4 月龄新西兰兔（n=16）随机分为两组：一组给予高脂饮食并进行球囊损伤（实验组，n=10），一组给予高脂饮食（对照组，n=6）。在第 2 周（研究开始时）和第 12 周（研究结束时）测量禁食过夜的兔子的血脂谱。在第 12 周，实验组兔子在麻醉下进行 IVUS 检查。处死兔子，取出腹主动脉 5cm 段。对动脉切片进行病理和免疫组织化学分析。所有给予高脂饮食的兔子的血清脂质水平均升高，其中低密度脂蛋白胆固醇（LDL-C）水平升高最多。在第 2 周时，两组之间六种生物标志物（高敏 C 反应蛋白、基质金属蛋白酶-3、白细胞介素[IL]-1、IL-10、肿瘤坏死因子-α和氧化[ox]-LDL）的水平没有差异，但在第 12 周时实验组水平较高。对实验组的 276 个动脉粥样硬化斑块进行了分析。VH-IVUS 对非钙化和钙化薄帽纤维粥样瘤的检测灵敏度分别为 87%和 92%。VH-IVUS 正确识别非钙化和钙化纤维粥样瘤的比例分别为 85%和 89%。对于病理性内膜增厚的检测，VH-IVUS 的灵敏度为 79%，阳性预测值为 78%。线性回归分析显示，组织学和 VH-IVUS 对纤维纤维脂肪组织、坏死钙化组织和融合坏死核心的百分比面积具有很强的相关性。内-中膜边界的观察者内和观察者间变异性较低。兔子的内皮损伤后再给予高脂饮食是诱导动脉粥样硬化的可行方法，而 VH-IVUS 是一种可行、可重复且有价值的体内易损斑块识别方法。
