Optimal Timing of Thoracic Endovascular Aortic Repair for Uncomplicated Type B Aortic Dissection: A Systematic Review and Meta-Analysis

Objective: Type B aortic dissections (TBAD) have a high mortality rate and are challenging to both classify and manage. There is significant evidence supporting the use of early intervention in complicated TBAD with thoracic endovascular aortic repair (TEVAR). Currently, there is equipoise regarding the optimal timing for TEVAR in TBAD. This systematic review answers whether early TEVAR in the hyperacute or acute phase of the disease has improved aorta related events in the one year follow up period with no change in mortality rate when compared with TEVAR in the subacute or chronic phase.Data sources: A systematic review and meta-analysis was performed with Preferred Reporting Items for Systematic Reviews and Meta-Analyses literature search guidelines for MEDLINE, Embase, and Cochrane Reviews until 12 April 2021. Inclusion and exclusion criteria targeting the review objective and high quality research were employed by separate authors.Review methods: These studies were then reviewed for suitability, risk of bias, and heterogeneity using the ROBINS-I tool. Results were extracted for the meta-analysis with RevMan using odds ratios with 95% confidence intervals with I2 used to assess heterogeneity.Results: Twenty articles were included. A meta-analysis showed no significant difference between acute phase TEVAR (excluding the hyperacute phase) and subacute or chronic phase TEVAR for the all cause 30 day and one year mortality rates. Aorta related events in the 30 day post-operative period were unaffected by the timing of intervention but had significant improvement in aorta related events in the one year follow up favouring TEVAR in the acute phase compared with subacute or chronic phase. Risk of confounding was high but with low heterogeneity.Conclusion: Without prospective randomised controlled studies, it is evident that there is improved aortic remodelling in long term follow up with intervention in the acute setting from three to 14 days after symptom onset. This suggests that TEVAR in the acute period of TBAD is both safe and beneficial, and can be considered for early stent grafting based on clinical, anatomical and patient factors.