Influence of measurement and sizing techniques in thoracic endovascular aortic repair on outcome in acute complicated type B aortic dissections

OBJECTIVES: Thoracic endovascular aortic repair (TEVAR) is the first-line therapy in acute complicated type B aortic dissections (cTBAD). Nevertheless, no evidence-based consensus on the optimal measurement technique and sizing for TEVAR in cTBAD exists. The aim was to evaluate how different measurement and sizing techniques for TEVAR affect long-term outcomes. METHODS: Retrospective analysis investigating the association between sizing and postoperative results after TEVAR in patients with cTBAD, treated between January 2003 and December 2020. Diameter measurements were performed perpendicular to a centreline in pre-interventional Computed tomography angiographies. Oversizing was determined by measuring aortic diameter in zone 2 of the aortic arch in relation to the implanted stent graft, and categorized into 2 sizing groups (≤10% and >10%). The primary outcome was freedom from aortic-related events. Secondary outcomes included mortality and a comparison of 3 alternative measurement techniques considering the estimated pre-dissection diameter. RESULTS: Fifty-seven patients (median age 69, interquartile range 59.6–78.2 years) were included. Stent graft oversizing by ≤10% showed a trend towards fewer aortic-related events hazard ratio 0.455 (95% confidence interval 0.128–1.624, P = 0.225). The 3 measurement techniques using the pre-dissection aortic diameter differed by a mean of 1.7–4.0 mm with a variability of up to 8.4 mm. In none of the 57 patients, the same stent graft would have been chosen based on the different measurement techniques using an oversizing ≤10%. CONCLUSIONS: TEVAR oversizing of ≤10% in patients with cTBAD might reduce aortic-related events up to 50%. Consensus on measurement techniques of the pre-dissection aortic diameter and stent graft sizing is of paramount importance.