Risk factors for distal stent graft-induced new entry in type B aortic dissections: Systematic review and meta-analysis

Background: After the use of thoracic endovascular aortic repair in the management of type B aortic dissection (TBAD), there has been increasing recognition of the phenomenon of stent graft-induced new entry (SINE) as a late complication of thoracic endovascular aortic repair, with risk factors for SINE identified. We performed a meta-analysis of contemporary studies to establish the risk factors for distal SINE (dSINE). Methods: A systematic search of the literature was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines to investigate the risk factors for dSINE. Data from population-cohort and caseecontrol studies were extracted to compute a conventional meta-analysis by combining the odds ratio using the generic inverse variance function on RevMan 5.3. Furthermore, a meta-analysis of proportions using the Freeman-Tukey double arcsine transformation was performed to compare the incidence of acute and chronic TBAD. Results: Seventeen studies assessing the data of 3962 patients met the eligibility requirements and were included in the review. The pooled proportion of dSINE in TBAD cases treated with thoracic endovascular aortic repair is 10.1%. The relative risk of incidence of dSINE in chronic TBAD compared to acute TBAD is 3.12. The chronicity of TBAD and excessive distal oversizing ratio was demonstrated to be positively associated with dSINE with odds ratios of 2.25 and 2.06, respectively. Stent grafts with connecting bars were also positively associated with dSINE, but this lacked statistical significance. Conclusions: This meta-analysis demonstrated that chronic TBAD and an excessive distal oversizing ratio are both positively and independently associated with the incidence of dSINE tears in TBAD. This should be taken into consideration when planning interventions in these patient cohorts.