Early Experience with Inner Branch Stent-Graft System for Endovascular Repair of Thoraco-Abdominal and Pararenal Abdominal Aortic Aneurysm

Objectives: We aim to evaluate technical and clinical outcomes with E-nside stent-graft for thoraco-abdominal aortic aneurysm (TAAA) and pararenal abdominal aortic aneurysm (PAAA) endovascular treatment at our University Hospital Center. Methods: Retrospective analysis of patients electively treated by inner branched EVAR (iBEVAR) between 05/2021 and 03/2023. Demographics, procedural and clinical data were analyzed. Technical success and clinical outcomes, such as access-site related complications were reported. Perioperative and early mortality rate, freedom from aortic reintervention, Target vessels (TVs) patency and endoleak rate were evaluated during the follow-up. Technical aspects (external iliac artery diameter, iliac tortuosity, extent of aortic coverage) were retrospectively analyzed. Results: Twenty-two patients included (age 75.9±5.5; 72.7% male). Aneurism extent was Craw-ford I=4 (18.2%), III=8 (36.4%), IV=5 (22.7%), V=1 (4.5%) and PAAA=4 (18.2%). Mean aortic di-ameter was 63.5±9.9mm. The technical success 95.5% (assisted primary success 100%). The clini-cal success 86.4%. Perioperative and early freedom from all-cause mortality rate 90.9% and 90%, respectively. No case of inter-stage aortic-related mortality reported, as no permanent/temporary spinal cord ischemia (SCI). Seventy-eight out of 81 patent TVs were incorporated through a bridging stent (96.3%). TV success 95.1%. Mean external iliac artery (EIA) diameter 7.5±1.1mm. Twelve patients (six women, 100%) were considered outside the instructions for use (IFU) due to narrow iliac arteries. One access-site related complication reported. Conclusions: Our experience confirms that E-nside has promising technical and clinical success rates, as low reintervention rate, but requires a great sacrifice of healthy aorta and adequate iliac arteries that still represent a limitation, especially among women. Mid- to long-term studies and prospective registries are mandatory to evaluate long-term efficacy and safety, as a comparison between E-nside and other alternative off-the-shelf solution.