OBJECTIVE/BACKGROUND Proximal type I endoleaks are associated with abdominal aortic aneurysm (AAA) growth and rupture and necessitate repair. The Nellix™ EndoVascular Aneurysm Sealing (EVAS) system is a unique approach to AAA repair, where the appearance and treatment of endoleaks is also different. This study aimed to analyse and categorise proximal endoleaks in an EVAS treated cohort. METHODS All patients, treated from February 2013 to December 2015, in 15 experienced EVAS centres, presenting with proximal endoleak were included. Computed tomography scans were analysed by a core laboratory. A consensus meeting was organised to discuss and qualify each case for selection, technical aspects, and possible causes of the endoleak. Endoleaks were classified using a novel classification system for EVAS. RESULTS During the study period 1851 patients were treated using EVAS at 15 centres and followed for a median of 494 ± 283 days. Among these, 58 cases (3.1%) developed a proximal endoleak (1.5% early and 1.7% late); of these, 84% of 58 patients were treated outside the original and 96% outside the current, refined, instructions for use. Low stent positioning was the most likely cause in 44.6%, a hostile anatomy in 16.1%, and a combination of both in 33.9%. Treatment, by embolisation or proximal extension, was performed in 47% of cases, with a technical success of 97%. CONCLUSION The overall incidence of proximal endoleak after EVAS is 3.1% after a mean follow-up period of 16 months, with 1.5% occurring within 30 days. Their occurrence is related to patient selection and stent positioning. Early detection and classification is crucial to avoid the potential of sac rupture.

中文翻译：

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编辑选择-使用Nellix™装置封闭血管内动脉瘤后I型近端内漏的发生和分类。

目的/背景I型近端内漏与腹主动脉瘤（AAA）的生长和破裂有关，需要修补。Nellix™血管内动脉瘤封闭（EVAS）系统是AAA修复的独特方法，内渗漏的外观和处理也有所不同。这项研究旨在分析和分类在EVAS治疗的队列中的近端内漏。方法纳入2013年2月至2015年12月在15个经验丰富的EVAS中心接受治疗的所有患者，这些患者均表现为近端内漏。核心实验室对计算机断层扫描进行了分析。组织了一次共识会议，讨论并确定每种情况的选择，技术方面以及内漏的可能原因。使用新颖的EVAS分类系统对内漏进行分类。结果在研究期间，在15个中心使用EVAS治疗了1851例患者，中位时间为494±283天。其中58例（3.1％）发生近端内漏（早期为1.5％，晚期为1.7％）。在这些患者中，有58％的患者中有84％接受了原始治疗以外的治疗，而有96％的患者接受了现行的使用说明书之外的治疗。支架定位低是最可能的原因，占44.6％，对人体解剖结构的敌意为16.1％，两者的结合为33.9％。47％的病例通过栓塞或近端伸张进行了治疗，技术成功率为97％。结论在平均随访16个月后，EVAS后近端内漏的总发生率为3.1％，其中30天之内发生率为1.5％。它们的发生与患者选择和支架定位有关。