The importance of infrarenal sealing zone assessment in endovascular aneurysm repair

An abdominal aortic aneurysm (AAA) is a dilatation of the abdominal aorta and occurs in 2-8% of the population. AAAs carry a high risk of rupture, often resulting in fatalities. Therefore, patients undergo preventive treatment with endovascular aneurysm repair (EVAR). During EVAR, an endograft is inserted to exclude the aneurysm from blood flow. Ensuring adequate contact surface (sealing zone) between the endograft and the aortic wall below the renal arteries (infrarenal) is crucial to prevent complications, such as proximal leakage of blood into the aneurysm (type 1a endoleak).

Currently, annual CT-scans are performed to detect complications post-EVAR. However, the assessment of the infrarenal sealing zone is often overlooked, and complications are missed. This is why the primary goal of this thesis was to advocate for structured sealing zone assessment following EVAR.

Our approach began with defining the preoperative and postoperative sealing zones, and we developed a decision algorithm to determine the most appropriate follow-up strategy. Additionally, we demonstrated that the length of the postoperative sealing zone is a predictor for the development of type 1a endoleaks. A diminishing sealing zone length may indicate the onset of a type 1a endoleak as well. Furthermore, we explored the performance of a novel endograft for EVAR in patients with challenging aortic anatomy.

The sealing zone length serves as a crucial quality outcome measure that should be routinely evaluated. While there are still challenges to overcome, the time is ripe to incorporate structured sealing zone assessment into clinical EVAR practice to proactively prevent complications.