Theoretical Applicability of Different Occluder Systems for Entry Closure in Type B Aortic Dissection: An Image-Morphological Study.

Objective: Type B aortic dissection is a life-threatening medical condition. Endovascular closure of the primary entry by means of TEVAR is considered, nowadays, the gold standard if operative treatment is necessary. The aim of this study is to analyse the theoretical applicability of selective endovascular entry sealing using different occluder systems. Methods: A CT-graphic analysis of 102 patients who received TEVAR from January 2017 to June 2023 was performed. Patients with an intramural haematoma were excluded. The study patients were divided in two groups: type B aortic dissection (n = 87) and distal stent graft-induced new entry (n = 15). The TBAD group included patients with acute (n = 63), subacute (n = 12), and chronic aortic dissections (n = 12). The CTA analysis of the location, length, and width of the entry was performed using Aquarius iNtuition (TeraRecon, Inc., Foster City, CA, USA). After completion of the data collection, the possible application of all three occluder systems (ASD-Occluder, Septal-Occluder, and Amplatzer™-Occluder) was analysed, with reference to the Instructions for Use. Results: The ASD-Occluder from GORE is produced in five different sizes. It can be used in 81.4% (n = 83) of all patients in the overall study, including 82.8% TBAD (n = 72) and 73.3% of dSINE (n = 11) patients. When using the ASD-Occluder, 10.3% (n = 9) of patients are expected to have complete vascular coverage of the LSA based on our CTA analysis. The Septal-Occluder from GORE is offered in three different sizes. Complete entry closure can theoretically be achieved in fifty patients (57.5%) with TBAD and in nine patients (60%) with dSINE, based on CTA analysis and IFU criteria. With the use of the Septal-Occluder, 3.9% (n = 4) of the dSINE patients and 4.6% (n = 4) of the TBAD patients were expected to have complete aortic branch occlusion. The Amplatzer™-Occluder from Abbott is provided in 27 different sizes to effectively seal defects with a diameter of 4 to 56 mm. It can technically be used in 90.1% of patients (n = 92), of which 89.7% with TBAD (n = 78) and 93.3% with dSINE (n = 14) to completely seal the entry. Conclusions: CTA analysis in patients with TBAD and dSINE demonstrated that by the theoretical application of occluder systems, a seal of the entry would be achieved in 57.8% to 90.1% of the patients. However, in addition to entry closure, the use of occluder systems can also lead to unintentional partial (10.7-23.5%) or complete (3.9-22.5%) coverage of adjacent aortic branches. The clinical significance and applicability of the occluder system should be reviewed in future studies and practical applications to evaluate safety, efficacy, and possible complications in order to define the benefit-risk balance.