E ndovascular aneurysm repair (EVAR) is universally accepted as an alternative to open surgery for the treatment of infrarenal abdominal aortic aneurysms because of its association with lower perioperative mortality and morbidity (1). The main drawback of EVAR is the relatively high rate of re-interventions (approximately 20%) required during the follow-up (1); endoleaks are usually the culprit responsible for these re-interventions. Type II endoleaks are most common, with a frequency varying from 10% to 25%, in EVAR procedures (2). They are caused by retrograde perfusion of the aneurysm sac from collateral aortic branches.In the majority of cases, type II endoleaks are benign and resolve spontaneously during follow-up. However, it has been shown both clinically and experimentally that type II endoleaks are associated with increased sac pressure (3). Interestingly, in a multivariate analysis from a series of 873 patients, it was documented that type II endoleak persisting for more than six months was a significant predictor of aneurysm rupture (P = 0.03) (4). Considering the lack of regularity in imaging follow-up, especially on a long-term basis, it is obvious that a small but existing minority of patients with untreated type II endoleaks may suffer from aneurysm rupture.Several studies have investigated potential correlations between preoperative characteristics of the aortic anatomy and the development of type II endoleaks following an EVAR (5-9). Although some studies failed to identify anatomic predictors for type II endoleak development (5), others with larger numbers of patients showed that preoperative patency of the aortic branches increases the possibility of type II endoleak development (6-9). Sampaio et al. (8) have not only focused on preoperative patent arteries but have also studied the aneurysm sac thrombus load in relation to type II endoleak development.The aim of our study was to define these potentially high-risk patients that are candidates for a more intense follow-up protocol. We have specifically focused on persistent type II endoleaks (present at six months after EVAR) because these of all type II endoleaks are implicated most frequently in late adverse outcomes (4). Based on previous studies, we investigated the role of preoperative patent aortic branches and sac thrombus formation as potential predictors of persistent (longer than six months) type II endoleak development.
Materials and methods
Patient populationOne hundred forty-nine patients (144 males, 5 females) with infrarenal abdominal aortic aneurysm (AAA) were treated with EVAR in our institution by a team of interventional radiologists, anesthesiologists, and vascular surgeons. Only patients that strictly adhered to the
INTERVENTIONAL RADIOLOGY ORIGINAL ARTICLE
Risk factors for the development of persistent type II endoleaks after endovascular repair of infrarenal abdominal aortic aneurysmsElias Brountzos, Georgios Karagiannis, Irene Panagiotou, Chara Tzavara, Efstathios Efstathopoulos, Nikolaos KelekisFrom the 2nd Department o...