A multi-institutional survey of interventional radiology for type II endoleaks after endovascular aortic repair: questionnaire results from the Japanese Society of Endoluminal Metallic Stents and Grafts in Japan.

Purpose: To investigate the current status of interventional radiology (IR) procedures for a type II endoleak (T2EL) in Japan, and to identify the technical aspects that affect treatment results.
Materials and Methods: A retrospective survey was conducted by distributing questionnaires to 25 institutions. The eligibility criteria were endovascular aortic repair (EVAR) performed using commercial stent grafts and IR performed for T2EL between January 2007 and December 2013. Technical success was defined as disappearance of the EL on digital subtraction angiography immediately after embolization, and imaging success was defined as no EL on contrast-enhanced computed tomography within 6 months. Statistical comparisons of the number of involved branches, embolization level, embolic material, and changes in aneurysm size were made between the imaging success and imaging failure groups. The technical and imaging success rates were also compared between the initial therapy and repeat groups.
Results: A total of 166 cases were investigated. Initial therapy was performed in 147 cases (88.6 %), with repeat therapy in 19 cases (11.4 %). Transcatheter arterial embolization (TAE) was used most frequently, in 161 cases (97 %), with direct puncture (DP) used in 5 cases (3 %). Both coil embolization for the branches and NBCA embolization for the sac were frequently chosen. The technical success rate was 83.2 % (TAE group), and the imaging success rate was 46.5 % (TAE + DP groups). Branch + sac embolization was performed more frequently in the imaging success group. There was no significant difference in the number of involved branches or embolic material between the imaging success and imaging failure groups. Enlargement of the aneurysm was more frequently seen in the imaging failure group. There were no significant differences in the technical success and imaging success rates between the initial therapy and repeat groups.
Conclusion: This is the first report of a multi-institutional questionnaire survey of IR procedures for T2EL after EVAR in Japan that was conducted to determine the current status. Enlargement of aneurysm size after embolization was more frequently seen in the imaging failure group. It is important to embolize both branch and sac to achieve imaging success, regardless of embolic material. Long-term outcomes need to be investigated.