Conservative Treatment of Retrograde Aortic Dissection after Endovascular or Hybrid repair of descending aorta pathologies.

Background: Retrograde type A dissection (RTAD) represents a rare but possible lethal complication of thoracic endovascular aortic repair. Intervention is often recommended but conservative management has been advocated in selected cases.

Methods: We performed a systematic review of the literature through MedLine and Cochrane databases over the last 24 years to identify reported cases of RTAD managed conservatively. Primary endpoint was the overall and aortic-related mortality, the morbidity and need for intervention during follow-up. The underlining causes and indications for conservative management were also investigated. (Protocol on Prospero CDR RD42024542966) RESULTS: A total of 2305 papers identified, and 10 articles were included (20 cases). Reasons for conservative treatment were age(n=8,40%) and/or haemodynamic stability(n=16,80%) and/or unfitness for surgery(n=12,60%). Causes of RTAD were fragile aortic wall in acute type B aortic dissection (n=10,50%), Marfan syndrome (n=2, 10%), use of stents with proximal barbs/bare springs (n=5, 25%), diameter of the ascending aorta>40 mm(n=2, 10%), and intraoperative type IA endoleak (n=2, 10%). Three patients (15%) were lost at follow-up immediately after discharge; one(5%) died in-hospital from aortic rupture. At a mean follow-up of 33.5 months (range 9-60), overall survival was 88.2%(n=15/17and aortic-related mortality (n=2/20). No complications nor interventions during the follow-up period were reported.

Conclusion: Mortality rate following RTAD is high and surgery allow improve survival. Conservative management might represent a viable option for selected patients. However, current evidence is poor and needs to be validated by further and more robust data before such a strategy could be suggested more widely.