Mazzaccaro Daniela, Ambrogi Federico, Milani Valentina, Modafferi Alfredo, Marrocco-Trischitta Massimiliano Maria, Malacrida Giovanni, Righini Paolo, Nano Giovanni
Operative Unit of Vascular Surgery, IRCCS Policlinico San Donato, Milan, Italy.
Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy.
Ann Vasc Surg. 2020 Aug;67:213-222. doi: 10.1016/j.avsg.2020.02.026. Epub 2020 Mar 20.
The aim of this study is to investigate the correlation of clinical and ultrasound parameters with characters of vulnerable atherosclerotic carotid plaque, as evaluated at preoperative magnetic resonance angiography (MRA), in patients submitted to carotid endarterectomy (CEA), in order to develop a clinical risk score for plaque vulnerability.
Preoperative data of patients submitted to CEA for significant carotid stenosis from January 1, 2012 to December 31, 2016 were retrospectively collected. The available case series was randomly divided into 2 groups, including a training (60%) and a validation series (40%). Data of plaque vulnerability were assessed at preoperative MRA scans. Univariate analysis was used on the training series to correlate the preoperative covariates available to the features of plaque vulnerability. Therefore, a backward selection procedure was performed again on the training series and on the validation series to assess if the same variables were associated to data of plaque vulnerability, in order to obtain a prediction model for the risk of plaque vulnerability. Odds ratios (ORs) with 95% confidence intervals were reported. P values <0.05 were considered statistically significant.
The training case series consisted of 352 patients, while the validation case series of 248 patients. After univariate analysis and logistic regression, on the training and the validation series respectively, 6 variables were significantly associated to features of vulnerable plaque at preoperative MRA. These included male sex (OR 2.05), diabetes mellitus (OR 3.06), coronary artery disease (OR 1.95), neutrophil/lymphocyte ratio (OR 17.99), platelet counts (OR 1.03), and gray-scale median value (OR 0.84). A nomogram was then obtained from the final logistic model, in order to predict the probability of the presence of vulnerable carotid plaque, using a weighted points system. This risk score was then applied to the validation series. The validation data were found to have a C-index of 0.934.
Sex, diabetes mellitus, coronary artery disease, neutrophil/lymphocyte ratio, platelet counts, and gray-scale median value were significantly associated to the features of vulnerable plaque at preoperative MRA in patients undergoing CEA. In particular, when combined together in a "risk score," these variables provided an accurate probability of the presence of a vulnerable plaque at MRA scans.
本研究旨在探讨在接受颈动脉内膜切除术（CEA）的患者中，临床和超声参数与术前磁共振血管造影（MRA）评估的易损性动脉粥样硬化颈动脉斑块特征之间的相关性，以便制定斑块易损性的临床风险评分。
回顾性收集2012年1月1日至2016年12月31日因严重颈动脉狭窄接受CEA治疗的患者的术前数据。将可用病例系列随机分为两组，包括训练组（60%）和验证组（40%）。术前MRA扫描评估斑块易损性数据。对训练组进行单因素分析，以将术前可用的协变量与斑块易损性特征相关联。因此，再次对训练组和验证组进行向后选择程序以评估相同变量是否与斑块易损性数据相关，以便获得斑块易损性风险的预测模型。报告具有95%置信区间的比值比（OR）。P值<0.05被认为具有统计学意义。
训练病例系列包括352例患者，验证病例系列包括248例患者。经过单因素分析和逻辑回归，在训练组和验证组中，分别有6个变量与术前MRA扫描时易损斑块的特征显著相关。这些变量包括男性（OR 2.05）、糖尿病（OR 3.06）、冠状动脉疾病（OR 1.95）、中性粒细胞/淋巴细胞比值（OR 17.99）、血小板计数（OR 1.03）和灰度中位数（OR 0.84）。然后从最终逻辑模型中获得列线图，以便使用加权积分系统预测易损颈动脉斑块存在的概率。然后将该风险评分应用于验证组。发现验证数据的C指数为0.934。
在接受CEA治疗的患者中，性别、糖尿病、冠状动脉疾病、中性粒细胞/淋巴细胞比值、血小板计数和灰度中位数与术前MRA扫描时易损斑块的特征显著相关。特别是，当这些变量组合成一个“风险评分”时，它们提供了MRA扫描时易损斑块存在的准确概率。
