Endoleak management and postoperative surveillance following endovascular repair of thoracic aortic aneurysms

摘要

As with endovascular repair of abdominal aortic aneurysms (EVAR), thoracic endovascular aortic repair (TEVAR) has become an accepted and preferred alternative to open surgical repair for the treatment of thoracic aortic aneurysms (TAAs). The incidence of TAAs is approximately 6/100,000 person-years, the risk of rupture for large TAAs is as high as 74% without repair, and >90% of patients do not survive a ruptured TAA. TEVAR offers the potential for aneurysm exclusion while avoiding a thoracotomy and aortic cross-clamping as well as the increased morbidity and mortality associated with open surgical repair. Unlike the minimal imaging required after open repair, however, patients undergoing TEVAR require lifelong postoperative surveillance imaging to detect some of the complications unique to EVAR. These include endoleak formation, endograft migration, endograft fracture, and aortic neck dilatation. (See the article by Drs Halandras and Milner for a more detailed description of late complications other than endoleak.) Although the detection and management of endoleaks after EVAR has been well documented, less has been reported about endoleaks after TEVAR. Despite recent advances in endovascular technology, endoleaks (primarily proximal type I endoleaks) remain an Achilles' heel of endovascular TAA repair because of the challenge of achieving a proximal seal between the endograft and the distal aortic arch. This article will address the incidence, mechanisms, and risk factors for endoleak formation after TEVAR, and will present the strategies and results for endoleak management and treatment as well as recommendations for surveillance imaging after TEVAR.