IYSC04 - Accuracy of Deployment and Conformability of the GORE Thoracic Branch Endoprosthesis

Objectives: To investigate the accuracy of deployment and conformability of the GORE Thoracic Branch Endoprosthesis (TBE).

Methods: We conducted a prospective multicenter study, with inclusion of consecutive patients treated by a Gore TBE (2024-2025) at two referral centers.
Pre- and post-operative computed tomography angiogram with centerline reconstruction was used for three-dimensional analysis. Endpoints were accuracy of deployment, conformability, and freedom from related reintervention.
Accuracy of deployment was evaluated as the distance between the left common carotid artery and proximal end of the stent graft, and gate alignment (angle between the left subclavian artery and the inner-branch gate). Conformability was assessed as bird-beak angle, lack of wall apposition at the proximal sealing zone, and branch angulation (angle between the inner branch and the side branch).
Multivariate analyses were performed to identify association between endpoints and preoperative anatomical variables.

Results: We included 42 patients, of which 38% had degenerative descending thoracic aneurysm, 33% acute or chronic type B dissection (33%), 21% a penetrating aortic ulcer or intramural hematoma, 8% a failed prior thoracic endovascular repair. All endografts were deployed in zone 2 and 21 procedures (50%) were performed urgently.
Preoperative arch type was categorized as type I in 6 patients (14%), type II in 15 (36%), and type III in 21 (50%). Median preoperative aortic tortuosity angle was 42° (IQR 36–49°). Technical success was achieved in 100% of cases.
At the post-implantation analysis, an optimal accuracy of deployment was achieved in 14 patients (33%), while 28 (67%) had suboptimal accuracy (median 2.5 mm, IQR 1.0–4.0) and a median gate alignment of 16° (IQR 8–22). Aortic arch tortuosity was linearly associated with the accuracy (P=.005). (Figure 1)
Median value of lack of wall apposition was 2.5 mm (IQR 1.0–4.0). Sixteen patients (38%) had a lack of apposition >5 mm, and median bird-beak angle was 10° (IQR 8–13°). On linear regression, arch tortuosity (P=.018), steeper arch angulation (P=.002) and steeper branch angulation (P=.015) were significantly associated with bird beak angle. (Figure 2)
Two reinterventions for type Ia endoleak were required during follow-up (median 12 months), both in cases with lack of wall apposition >8 mm.

Conclusions: The GORE TBE provides high technical success and acceptable accuracy and conformability. However, aortic tortuosity and arch angulation significantly influence wall apposition and alignment. These findings highlight the central role of preoperative anatomical characteristics in patient selection, planning, and optimization of TBE deployment. Longer term clinical data are still needed.