主动脉脱套与TEVAR术中支架源性主动脉脱套

Aortic intimal intussusception and intraoperative stent-graftinduced aortic intimal intussusception during TEVAR

急性主动脉夹层发生时内膜撕裂,如果撕裂形态呈现为周径上的环形破口,破口远端的内膜会脱离主动脉管壁并形成独立的内膜管腔,这个管腔顺着血流方向塌陷之后就会形成顺行脱套病变,即主动脉脱套。主动脉脱套发病率低,其总数的90%发生在主动脉夹层自然病程中,也可以是胸主动脉腔内修复术(TEVAR)的并发症。随着近年TEVAR技术的普及和手术数量的增加,手术相关并发症的数量也逐渐增加,但是TEVAR术中支架源性主动脉脱套(ISAII)的报道极为有限。该病作为一种罕见的夹层或并发症,并不被大多数医生所熟知,因此本文旨在介绍主动脉脱套和ISAII的概念、特点、诊断、分型以及处理原则与方法、注意事项,为临床工作提供理论支持,让更多患者受益。出现在自然病程中的主动脉脱套,有时需要心电门控计算机体层成像血管造影或心脏超声结合使用才能明确诊断,这种病变大部分情况下可以在开放手术中直视下修补;但是在TEVAR手术中,脱套病变往往只能通过数字减影血管造影发现,而且大部分情况下优先推荐血管腔内技术修复。如果没有及时发现脱套病变,将会出现灾难性后果。在TEVAR术中,如果在常规造影后发现ISAII,首先需要保留手术器械和通路。其次需要造影明确脱套分型,根据不同的分型,分清主动脉结构的改变,选择不同的处理方案。ISAII分三型,Ⅰ型ISAII病变局限于胸主动脉支架覆盖部位,无需额外支架植入;Ⅱ型ISAII病变位于支架覆盖远端,但局限于胸主动脉段,治疗上需要在胸主动脉段植入覆膜支架,固定内膜团块,开通真腔;Ⅲ型ISAII病变位于腹主动脉段,最危险,对术者的手术决策和技术要求也最高。除了胸主动脉覆膜支架植入,还需要在腹主动脉段使用裸支架固定内膜团块,开通真腔血供。

When an acute aortic dissection occurs,the intima tears.If the tear forms a circumferential rupture,the intima distal to the tear detaches from the aortic wall and forms an independent intimal lumen.As this lumen collapses along the direction of blood flow,it creates an antegrade intimal detachment,known as aortic intimal intussusception.Aortic intimal intussusception is rare,with 90%of cases occurring during the natural progression of an aortic dissection,but it can also be a complication of thoracic endovascular aortic repair(TEVAR).With the increasing prevalence and number of TEVAR procedures in recent years,the incidence of surgery-related complications has also risen.However,reports on intraoperative stent graft-induced aortic intimal intussusception(ISAII)during TEVAR are extremely limited.This condition,being a rare type of dissection or complication,is not well-known to most physicians.Therefore,this article aims to introduce the concept,characteristics,diagnosis,classification,treatment principles and methods,and precautions of aortic intimal intussusception and ISAII,providing theoretical support for clinical practice and benefiting more patients.Aortic intimal intussusception occurring during the natural progression of the disease sometimes requires a combination of electrocardiogram-gated computed tomography angiography or cardiac ultrasound for a definitive diagnosis.In most cases,such lesions can be repaired under direct vision during open surgery.However,during TEVAR procedures,intussusception lesions are often only detectable by digital subtraction angiography,and in most cases,endovascular techniques are recommended for repair.If the intussusception lesions are not promptly identified,catastrophic consequences can occur.During TEVAR,if ISAII is detected after routine angiography,it is crucial to first preserve the surgical instruments and access routes.Next,angiography is required to clarify the type of intussusception and to distinguish the structural changes in the aorta,selecting the appropriate treatment strategy based on the classification.ISAII is classified into three types.Type I ISAII lesion is confined to the stent-covered area of the thoracic aorta and do not require additional stent implantation.TypeⅡISAII lesion is located distal to the stent-covered area but are confined to the thoracic aorta.Treatment involves implanting a covered stent in the thoracic aorta to fix the intimal flap and restore true lumen patency.TypeⅢISAII lesion is located in the abdominal aorta,which is the most dangerous and requires the highest level of surgical decision-making and technical skill.In addition to implanting a covered stent in the thoracic aorta,a bare stent is needed in the abdominal aorta to fix the intimal flap and restore true lumen blood supply.