Two-year target vessel-related outcomes following use of off-the-shelf branched endografts for the treatment of thoracoabdominal aortic aneurysms

OBJECTIVE: The aim of this study was to assess clinical outcomes and target vessel patency through 2 years following thoracoabdominal aortic aneurysms (TAAA) repair with the off-the-shelf Zenith t-Branch Thoracoabdominal Endovascular Graft (William Cook Europe).

METHODS: This post-market observational study was conducted at three European sites with ambispective enrollment from 2012 to 2017. Patients underwent endovascular TAAA repair with the t-Branch graft and bridging stent grafts (BSGs) for the celiac (CA), superior mesenteric (SMA), left renal (LRA), and/or right renal (RRA) arteries. Follow-up was through 2 years, per sites' standard of care. Procedural and 1-year results were reported previously.

RESULTS: Eighty patients (mean age, 71.0±7.4 years; 70.0% men) were enrolled; six patients had symptomatic TAAAs, and 15 patients had contained ruptures. Technical success was achieved in 98.8% of patients (79/80). Median follow-up was 22.2 months (interquartile range, 9.2-25.1 months). At 24 months, Kaplan-Meier (KM) freedom from all-cause and aneurysm-related mortality were 78.5% and 98.6%, respectively. Beyond 12 months, 38 adverse events occurred in 20 patients, including two aortic ruptures (one study aneurysm and one non-study aneurysm) and six deaths (none aneurysm-related, as reported by the site). Compared with postprocedure, maximum aneurysm diameter decreased (>5 mm) in 84.6% (44/52), remained unchanged in 3.8% (2/52), and increased (>5 mm) in 11.5% (6/52) of patients with imaging follow-up after 12 months. No conversions to open repair, and no t-Branch graft or other endograft component migration or integrity issues were reported. No loss of patency was reported in the t-Branch or iliac limb grafts throughout the study. Throughout study duration, four patients had five imaging-reported BSG compressions, none of which required secondary intervention. KM freedom from secondary intervention was 76.3% at 24 months. Fourteen target vessel-related secondary interventions were performed, primarily consisting of stent placement for endoleak, stenosis, or occlusion. KM freedom from loss of primary patency was 94.8%, 100%, 91.3%, and 89.3% for the CA, SMA, LRA, and RRA, respectively, at 24 months. KM freedom from loss of secondary patency in the CA, SMA, LRA, and RRA were 96.3%, 100%, 98.2%, and 98.3% at 24 months, respectively. A total of 298 vessels were targeted, of which 12 were occluded over the study period.

CONCLUSIONS: Primary and secondary target vessel patency rates through 2 years demonstrated durable repair with the t-Branch graft in patients treated for symptomatic or asymptomatic thoracoabdominal aortic aneurysms.