Anatomic Utility of Single Branched Thoracic Endograft During Thoracic Endovascular Aortic Repair.

Introduction: Single branched thoracic endografts (SBTEs) have been designed for pathology requiring zone 2 seal during thoracic endovascular aortic repair (TEVAR). Numerous criteria must be met to allow for their implantation. Our aim was to analyze anatomic suitability for a next generation SBTE.

Methods: We reviewed 150 TEVAR procedures between 2015 and 2019. Proximal seal was: zone 0 in 21 (16%), zone 1 in 4 (3%), zone 2 in 52 (40%), zone 3 in 45 (35%), and zone 4 or distal in 7 (5%). We analyzed the Zone 2 patient's angiograms and CT angiograms using centerline software to measure arterial diameters and length in relation to the left common carotid artery (LCCA), left subclavian artery (LSA) and proximal extent of aortic disease to determine if patients met anatomic criteria of a novel SBTE.

Results: Zone 2 average age was 64.4 ± 16.3 years; 34 patients were male (65%). Indications for repair were aneurysm (N = 9, 17%), acute dissection (N = 14, 27%), chronic dissection with aneurysmal degeneration (N = 7, 13%), intramural hematoma (N = 9, 17%), penetrating aortic ulcer (N = 5, 10%), and blunt traumatic aortic injury (BTAI, N = 8, 15%). LSA revascularization occurred in 27 patients (52%). Overall, 20 (38.5%) of the zone 2 patients met anatomic criteria. Patients with dissection met anatomic criteria less frequently than aneurysm (33% [10 of 30] vs 64% [9 of 14]). Patients treated for BTAI rarely met the anatomic criteria (1 of 8, 13%). The main anatomic constraints were an inadequate distance from the LCCA to the LSA takeoff and from the LCCA to the start of the aortic disease process.

Conclusion: Less than half of patients who require seal in zone 2 met criteria for this SBTE. Patients with aneurysms met anatomic criteria more often than those with dissection. The device would have little applicability in treating patients with BTAI.