Mechanical thrombectomy in COVID-19 positive patients with large vessel occlusion: Pooled review of individual case series

Background: COVID-19 has been shown to induce a hypercoagulable state thereby increasing the risk of arterial thrombosis resulting in Large Vessel Occlusion Stroke (LVOs) Objective: We performed a systematic review of published reports to study the clinical characteristics, and outcomes of COVID-19 acute ischemic stroke (AIS) patients with LVO treated with mechanical thrombectomy (MT) and compared them with historical controls Methods: We conducted a systematic literature search from December 2019 to July 2020 using multiple combinations of keywords from PubMed and Ovid databases according to the PRISMA meta-analyses and systemic reviews guidelines and then pooled data from individual case series We included studies where COVID -19 associated LVO cases were treated with MT and their clinical outcomes were reported We then compared these findings with the historic patient data from the five landmark randomized MT trials, the Hermes collaborators (HC) Results: An initial search generated 12 studies but after excluding case reports and multiple reports comprising of the same series of patients, a total of five reports consisting of 51 patients were analyzed The mean age of patients was 59 years (IQR 36-75), and 40 (78 %) were men Median NIHSS on presentation was 20 (IQR 10-29) AIS with LVO was the presenting manifestation of COVID-19 in 16 (20%) of patients Intracranial ICA was the most common site of occlusion found in 27 (53%) of patients with multi-territory occlusion in 10 (20 %) Final recanalization TICI ≥ 2b was achieved in 33 (64%) of patients but reocclusion was noted in 7 (14 %) Modified Rankin score (mRS) 0-2 was reported in 12 (23 %) of patients with 40 % in-hospital mortality When compared to historic data from HC, COVID -19 patients were younger (59 vs 69 years), presented with a higher median NIHSS score (20 vs 17), and had a higher prevalence of ICA terminus occlusion (53% vs21% ) Similarly, patient outcomes were poor in the COVID -19 group with mRs 0-2 in (23 % versus46 %) and mortality (40 % vs 15 %) compared to Hermes group Conclusion: COVID -19 AIS patients with LVO who underwent MT were younger, had multipleterritory occlusions with a propensity for ICA terminus location, and had poor angiographic andclinical outcomes as compared to historic data