RS21 - Five-Year Pivotal Trial Outcomes of a Conformable Endoprosthesis in Abdominal Aortic Aneurysms with Short Non-Angulated Infrarenal Seal Zones

Objectives: The Gore Excluder Conformable AAA Endoprosthesis (EXCC) received FDA approval in December 2020 for treatment of abdominal aortic aneurysms (AAA). In 2024, EXCC received FDA approved expanded treatment indication for highly angulated (≤90 degrees) and short (≥10mm) infrarenal aortic proximal seal zones (necks). Our objective is to report the five-year outcomes of the EXCC United States (US) pivotal clinical trial in the short, non-angulated cohort.

Methods: The EXCC investigational device exemption (IDE) pivotal trial short neck sub-study was prospectively conducted across 31 US sites and included patients with infrarenal necks measuring ≥10mm length and ≤60 degrees angulation. Five-year outcomes assessed patient safety (mortality, reintervention, rupture, conversion to open repair), device effectiveness (freedom from endoleak, migration, fracture, erosion, occlusion), and freedom from aneurysm sac expansion. These were assessed by core lab and adjudicated by independent review committee.

Results: 80 patients received EXCC implantation of which 53 (66%) were available for five-year follow-up. Patients were 88.8% male, mean 73.5 ± 8.14 years-old, 93.8% White, and had a mean BMI 29.5 kg/m2. The mean maximum AAA diameter was 57.7 mm (range 42.5-82.7mm) and the mean infrarenal aortic angle was 35.7 degrees (range 3-59 degrees). The neck length measured ≥10mm to < 15mm in 23 (29%) patients and ≥15mm length in 57 (71%). Table 1 details patient safety, device effectiveness and aneurysm-related outcomes across the five-year study period. No devices manifested obstruction, occlusion, erosion, or migration. There were no Type I or Type III endoleaks. AAA expansion ≥5mm was noted in 8 (10%) patients and 9 (11.3%) patients underwent reintervention, predominantly embolization for Type II endoleak. One patient (1.3%) experienced AAA rupture, while no patients underwent conversion to open repair. Overall five-year aneurysm-related mortality was zero for the cohort. There were no differences in AAA expansion (9.5% versus 10.5%, p=NS) or reinterventions (8.7% versus 12.3%, p=NS) between patients with a ≥10mm to < 15mm seal zone compared to patients with a ≥15mm seal zone, respectively.

Conclusions: The five-year outcomes of the EXCC US pivotal trial demonstrate excellent patient safety and device effectiveness endpoints. There is complete absence of aneurysm-related mortality, conversion to open repair, significant endoleak, or device occlusion/migration. Reinterventions and AAA sac expansion are infrequent and do not differ between short or standard infrarenal seal zone lengths. The EXCC device is safe and effective through five years for AAA necks measuring ≥10mm length and ≤60 degrees angulation.