Preoperative prediction of type II endoleak following standard EVAR

Introduction: Type II endoleak (T2EL) consists the most common complication after the endovascular repair of an abdominal aortic aneurysm (EVAR). Despite been generally considered as a benign condition, aortic sac expansion is possible, and for this reason patients should be kept under close surveillance. Aim of the study was to identify preoperative parameters that are related with a T2EL and create a predicting-scoring model. Methods: A prospective clinical study was made. All patients who underwent EVAR throughout a 12-month period in two hospitals, were included. Patients were followed for 12 months using a pre-specified protocol. Various clinical, anatomical and device specific parameters were examined as potential factors of T2EL, using univariate and multivariable analysis. Results: Overall, 73 patients were included. Three patients were excluded due to Type I endoleak. From the rest 70 patients, 17 (24.3%) developed a T2EL (Endoleak group). These patients were compared to the patients who did not develop a T2EL (No-Endoleak group, N=53). The analysis demonstrated that 3 parameters were related with the development of T2EL: the preoperative anticoagulant treatment, the number of patent arteries in the preoperative CT scan, and the nitinol skeleton of the endograft. Based on the multivariable analysis, the ABS-10 risk scoring system for the preoperative prediction of a T2EL was created as following: 4 points for prior chronic use of Anticoagulants, 1 point for each patent arterial Branch from the aneurysm sac, and 5 points for a nitinol endograft Skeleton. A score of 7 presented sensitivity 88%, specificity 62%, positive predictive value 43%, and negative predictive value 94%. Conclusions: A risk scoring system for the prediction of T2EL after standard EVAR was created. A score of less than 7 practically excludes the possibility of T2EL. External validation in larger populations is needed. Preoperative prediction of type II endoleak following standard EVAR 153 mal sac enlargement11, although the treatment of T2EL without changes of the aneurysmal sac remains controversial12-19. Little is known about the factors that can predict a T2EL preoperatively. A high suspicion of a postoperative T2EL after EVAR would be helpful for the proper selection of patients regarding the proper type of treatment they would receive including open repair. On the contrary, a minimal risk of T2EL will allow treating physicians choosing patients who will benefit of an EVAR without the question of a potential long-term hazard. Aim of this study was to determine factors that may be potentially predictive of early T2EL after standard EVAR, taking into consideration patients’ clinical data, aneurysm anatomic features, and endograft details.