Type III Arch Configuration as a Risk Factor for Carotid Artery Stenting: A Systematic Review of Contemporary Guidelines on Management of Carotid Artery Stenosis

Background: Type III arch configuration is frequently reported as a stroke risk factor for carotid angioplasty and stenting (CAS). We reviewed contemporary guidelines on management of carotid artery stenosis to assess the clinical relevance attributed to this anatomic feature in current clinical practice. Methods: The study was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. The PubMed, EMBASE, and Web of Science databases were searched to identify all guidelines on extracranial carotid disease published between January 2008 and March 2020. A total of 435 articles were screened. For multiple guidelines from the same writing group, only the most recent updated version was considered. Eighteen documents were identified for qualitative analysis. Results: Four guidelines specifically reported type III arch as a predictive factor of periprocedural complications after CAS. Two of them also provided a low level of evidence of their recommendation. None of the documents indicated the exact criteria for aortic arch classification. Three different methods to describe type III arch configuration were identified. Conclusions: Type III arch configuration is inconsistently included among stroke risk factors for CAS in contemporary guidelines, and variably defined. Further studies on the level of concordance between the 3 existing definition criteria are warranted.