Branch Thrombus after Endovascular Treatment with Arch Branched Devices for Aortic Arch Pathologies

Objective: The aim of this study was to describe the occurrence of branch thrombosis following endovascular treatment of aortic arch pathology using an arch branched device (ABD) and to determine whether this is influenced by clinical and geometric parameters. Methods: In this retrospective observational study of patients treated with an ABD in three centres, the primary endpoint was thrombus formation within a branch during follow up. Secondary endpoints were technical success, serious adverse events (SAEs), early and late death, stroke, and re-interventions. Geometric measurements (tortuosity index and curvature) were determined on pre- and post-operative computed tomography angiograms. Results: Thirty nine patients were treated and 68 antegrade branches were analysed (innominate artery, n = 27; common carotid artery [CCA], n = 40; left subclavian artery [LSA], n = 1). Thrombus was identified within seven branches (10%) on surveillance imaging (innominate artery, n = 6; CCA, n = 1; LSA, n = 0; p = .021) and was associated with a wider distal bridging stent diameter (median 14.0 mm [13.3, 15.3] vs. 8.7 mm [IQR 5.9]; p = .026), a higher degree of reversed tapering (4.3 mm [3.8, 5.2] vs. 1.2 mm [0.3, 3.1]; p = .023), use of polyethylene terephthalate (Dacron) covered (vs. expanded polytetrafluoroethylene) bridging stents (23% vs. 2%; p = .011), and higher body mass index (BMI) (32.1 kg/m ² [28.7, 36.2] vs. 25.7 kg/m ² [23.8, 29.2]; p = .029), but not with pre-operative or post-operative tortuosity index or curvature or alterations. Regarding secondary outcomes, the technical success rate was 97%, SAEs occurred in 15 patients (38%), early and late death rates were 8% and 23%, respectively, and early and late stroke rates were 5% and 23%, respectively. Conclusion: The risk of developing branch thrombosis after endovascular intervention with an ABD is considerable, especially of innominate artery branches, characterised by Dacron covered large diameter bridging stents, and in patients with a high BMI. Large prospective studies are required to analyse factors associated with branch thrombosis.