Histological evaluation of acute ischemic stroke thrombi may indicate the occurrence of vessel wall injury during mechanical thrombectomy

• DOI: 10.1136/neurintsurg-2021-017310
• Publication Date: 2021-05-11T17:25:24Z
• Authors: Oana Madalina Mer...; Mehdi Abbasi; Seán Fitzgerald; Daying Dai; Ram Kadirvel; Ricardo A Hanel; Albert J Yoo; Mohammed A Almekh...; Kennith F Layton; Josser E Delgado ...; Peter Kvamme; Vitor Mendes Pereira; Babak S Jahromi; Raul G Nogueira; Matthew J Gounis; Biraj Patel; Amin Aghaebrahim; Eric Sauvageau; Parita Bhuva; Jazba Soomro; Andrew M Demchuk; Ike C Thacker; Yasha Kayan; Alexander Copelan; Pouya Nazari; Donald Robert Can...; Diogo C Haussen; Alhamza R Al-Bayati; Mahmoud Mohammaden; Leonardo Pisani; Gabriel Martins R...; Ajit S Puri; John Entwistle; Alexander Meves; Jorge L Arturo Larco; Luis Savastano; Harry J Cloft; David F Kallmes; Karen M Doyle; Waleed Brinjikji
• Keywords: Neurosurgery; 610; Endothelial Cells; Thrombosis; stroke; Brain Ischemia; 3. Good health; Stroke; vessel wall; 03 medical and health sciences; Treatment Outcome; 0302 clinical medicine; Neurology; thrombectomy; Cardiovascular Diseases; Humans; Nervous System Diseases; Radiology; Ischemic Stroke; Thrombectomy

BackgroundSeveral animal studies have demonstrated that mechanical thrombectomy (MT) for acute ischemic stroke (AIS) may cause vessel wall injury (VWI). However, the histological changes in human cerebral arteries following MT are difficult to determine.ObjectiveTo investigate the occurrence of VWI during MT by histological and immunohistochemical evaluation of AIS clots.MethodsAs part of the multicenter STRIP registry, 277 clots from 237 patients were analyzed using Martius Scarlett Blue stain and immunohistochemistry for CD34 (endothelial cells) and smooth muscle actin (smooth muscle cells).ResultsMT devices used were aspiration catheters (100 cases), stentriever (101 cases), and both (36 cases). VWI was found in 33/277 clots (12%). There was no significant correlation between VWI and MT device. The degree of damage varied from grade I (mild intimal damage, 24 clots), to grade II (relevant intimal and subintimal damage, 3 clots), and III (severe injury, 6 clots). VWI clots contained significantly more erythrocytes (p=0.006*) and less platelets/other (p=0.005*) than non-VWI clots suggesting soft thrombus material.Thrombolysis correlated with a lower rate of VWI (p=0.04*). VWI cases showed a significantly higher number of passes (2 [1–4] vs 1 [1–3], p=0.028*) and poorer recanalization outcome (p=0.01*) than cases without VWI.ConclusionsHistological markers of VWI were present in 12% of AIS thrombi, suggesting that VWI might be related to MT. VWI was associated with soft thrombus consistency, higher number of passes and poorer revascularization outcome. There was no significant correlation between VWI and MT device.