腹主动脉瘤EVAR术后进展性Ⅱ型内漏的相关危险因素及风险预测模型研究

Risk factors and a risk prediction model for progressive type Ⅱ endoleak after EVAR for abdominal aortic aneurysm

摘要:

背景与目的 Ⅱ型内漏（T2EL）是腹主动脉瘤腔内修复术（EVAR）后最常见的并发症之一，其中部分患者可进展为瘤腔持续扩张并需再次干预。明确EVAR术后进展性T2EL的危险因素并进行风险分层，有助于优化围术期管理和随访策略。本研究旨在分析EVAR术后进展性T2EL的相关危险因素及其危险阈值，并构建预测模型。方法 回顾性分析2013年3月—2024年12月在天津医科大学总医院行EVAR术后出现T2EL的腹主动脉瘤患者临床资料。依据随访期间是否达到T2EL干预指征（瘤体最大直径与基线相比增加≥10 mm），将患者分为进展组（n=21）和稳定组（n=62）。比较两组患者的临床特征、解剖条件及手术相关因素，采用多因素Logistic回归分析筛选进展性T2EL的独立危险因素，通过受试者工作特征（ROC）曲线确定危险阈值，并构建列线图预测模型，对模型进行判别度、校准度及临床实用性评价。结果 进展组患者的瘤体最大直径、肠系膜下动脉（IMA）开口直径及通畅腰动脉（LA）数量均显著高于稳定组（均P<0.05）。多因素分析显示，瘤体最大直径、IMA开口直径及通畅LA数量是EVAR术后进展性T2EL的独立危险因素（均P<0.05）。ROC曲线分析表明，瘤体最大直径≥54.30 mm、IMA开口直径≥2.82 mm及通畅LA数量≥6条时，发生进展性T2EL的风险显著增加。基于上述因素构建的列线图模型一致性指数为0.858，经Bootstrap内部验证后校正一致性指数为0.837，模型具有良好的判别能力、校准度及临床获益。结论 瘤体最大直径、IMA开口直径及通畅LA数量是EVAR术后进展性T2EL的重要危险因素。基于上述因素构建的列线图预测模型可有效评估进展性T2EL的发生风险，但仍需多中心、前瞻性研究进一步验证。

Abstract:

Background and Aims Type Ⅱ endoleak (T2EL) is the most common complication after endovascular abdominal aortic aneurysm repair (EVAR). While many cases remain benign, a subset may progress with aneurysm sac enlargement and require reintervention. Identifying risk factors for progressive T2EL and establishing a reliable risk stratification model may improve perioperative decision-making and postoperative surveillance. This study aimed to investigate the risk factors and threshold values for progressive T2EL after EVAR and to develop a nomogram-based prediction model.Methods Clinical data of patients who developed T2EL after EVAR for abdominal aortic aneurysm between March 2013 and December 2024 were retrospectively reviewed. Patients were classified into a progressive group (n=21) or a stable group (n=62) based on whether intervention criteria (An increase in the maximum aneurysm diameter of ≥10 mm compared with baseline) were met during follow-up. Clinical characteristics, anatomical parameters, and operative variables were compared. Multivariate Logistic regression was performed to identify independent risk factors for progressive T2EL. Receiver operating characteristic (ROC) curves were used to determine optimal cutoff values. A nomogram prediction model was constructed and internally validated using discrimination, calibration, and decision curve analyses.Results The progressive group had a significantly larger maximum aneurysm diameter, greater inferior mesenteric artery (IMA) ostial diameter, and a higher number of patent lumbar arteries (LA) compared with the stable group (all P<0.05). Multivariate analysis identified these three variables as independent risk factors for progressive T2EL after EVAR (all P<0.05). ROC analysis demonstrated increased risk of progressive T2EL in patients with a maximum aneurysm diameter ≥54.30 mm, IMA ostial diameter ≥2.82 mm, and ≥6 patent LA. The nomogram achieved a C-index of 0.858, which remained robust after internal validation (corrected C-index: 0.837), showing good discrimination, calibration, and clinical utility.Conclusion Maximum aneurysm diameter, IMA ostial diameter, and the number of patent LA are key predictors of progressive T2EL after EVAR. The proposed nomogram provides effective individualized risk assessment, although external validation is required before widespread clinical application.