Long-term outcome of patients treated by TEVAR for type B aortic dissection or intramural hematoma depending on a healthy vs non-healthy proximal landing zone

Abstract

Abstract Objective Thoracic endovascular aortic repair (TEVAR) is the first-line therapy for complicated type B aortic dissection (TBAD) or intramural hematoma (IMH). However, depending on the location of the primary entry tear, there is paucity of data as to whether the proximal landing zone (PLZ) of the stent prosthesis must be in a non-dissected healthy part (healthy landing zone = HLZ) or in the dissected aorta (non-healthy landing zone= non-HLZ). Methods Retrospective analysis of patients who underwent TEVAR for acute (<14 days) or subacute (<3 months) TBAD or IMH from 2003–2020 at a single center. A HLZ was defined as a non-dissected aortic segment (length ≥2 cm). Primary endpoints were freedom from aortic reintervention and -growth (≥5 mm). Secondary endpoints involved stroke, retrograde type A aortic dissection, proximal stent graft induced new entry (pSINE), debranching failure, 30-day and overall mortality. Results 94 patients (age 70 years (interquartile-range (IQR): 59 to 78) were included. 84 (89%) presented with a TBAD and only ten (11%) with an IMH. CTA analysis revealed a HLZ in 62 (66%) patients. Debranching of the left subclavian artery was performed in 21 (22%) patients to extend the PLZ. The median follow-up time was 20 (IQR: 4.6 to 72.9) months. The overall aortic reintervention rate was 22%. Estimated re-intervention rate at 12 months was 13.1% for HLZ vs. 16.1% for non-HLZ and at 5 years 16.8% for HLZ 29.9% vs. for non-HLZ (P=0.187). Aortic growth was observed in 12 patients after 2.2 years (IQR: 0.8 to 5.9), with no significant difference in patients with HLZ vs. non-HLZ (11% vs 16%,P=0.535). No significant differences were observed for the secondary endpoints. 30-day mortality was 10% in both groups, P=1.0. Overall survival was 47% in the HLZ group vs. 41% in the non-HLZ group, P=0.663. A Cox proportional hazard model for reintervention with mortality as a competing risk showed a trend towards better long-term outcome for patients with a HLZ, hazard ratio 0.451 (95%-CI: 0.186–1.09, P=0.078). Conclusion In the majority of patients, it was possible to land in a HLZ. Consistently, reintervention rates, aortic growth, and mortality were higher in patients with non-HLZ compared with HLZ over the mid- and long-term. However, these differences were not statistically significant. Therefore, larger studies are urgently needed.