Flow-augmentation bypass in the treatment of acute ischemic stroke

Results of two randomized trials did not show benefit of revascularization with extracranial-intracranial (EC-IC) flow augmentation bypass in patients with symptomatic occlusion of internal carotid artery (ICA). However, patients with acute stroke were not included in these studies. Herein, we systematically analyze and discuss the literature about flow augmentation bypass for treatment of acute ischemic stroke.

This systematic review followed the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) statement. MEDLINE, Web of Science and EMBASE were independently searched by two reviewers for published series to identify literature relating to EC-IC bypass in the surgical management of acute ischemic stroke up to June 2020. Studies were categorized according to their level of evidence.

Nineteen studies met the inclusion criteria for the systematic literature review, including 16 level IV studies (ten case series and six6 case reports) and three level III studies (retrospective cohort case-control studies). Occurrence of fatal or non-fatal ischemic or hemorrhagic postoperative stroke, as well as clinical functional outcome at follow-up were considered as primary and secondary endpoints, respectively.

The literature about flow augmentation bypass for treatment of acute ischemic stroke is scarce and heterogenous, with only 19 studies. The results of the present systematic review encourage further study to explore and validate the use of EC-IC bypass in the treatment of anterior circulation acute ischemic stroke in highly selected patients (symptomatic and with persistent penumbra despite best medical/endovascular treatment).