The Impact of Arterial Collateralization on Outcome after Intra-Arterial Therapy for Acute Ischemic Stroke

Abstract

BACKGROUND AND PURPOSE:Although intra-arterial therapy for acute ischemic stroke is associated with superior recanalization rates, improved clinical outcomes are inconsistently observed following successful recanalization. There is emerging concern that unfavorable arterial collateralization, though unproven, predetermines poor outcome. We hypothesized that poor leptomeningeal collateralization, assessed by preprocedural CTA, is associated with poor outcome in patients with acute ischemic stroke undergoing intra-arterial therapy.

Impact of collaterals on the efficacy and safety of endovascular treatment in acute ischaemic stroke: a systematic review and meta-analysis

“…The quality of three studies was graded as <6 of the NOS, due to the inadequate follow-up and low comparability of the cohorts. The included studies were carried out in different countries or regions: 11 studies (1434 participants) in Europe,13–23 10 (707 participants) in Asia,24–33 8 (435 participants) in North America12 34–40 and 1 (87 participants) in Australia,41 and the remaining 5 were cross-continental studies (879 participants) 2 9 42–44. Concerning the mode of endovascular treatment, 8 studies (454 participants) reported correlations between collateral status and efficacy and/or safety outcomes in patients receiving intra-arterial thrombolysis;12 13 22 24 25 34 39 40 also, there were four studies (421 participants) in patients receiving mechanical therapies, including mechanical clot disruption with or without urgent angioplasty/stenting,2 20 30 44 while other studies reported such data in cohorts with various modes of EVT.…”

“…For the collateral grades being correlated with outcomes, 12 studies used the American Society of Intervention and Therapeutic Neuroradiology/Society of Interventional Radiology (ASITN/SIR) collateral flow grading system45 by digital subtraction angiography (DSA),2 9 17 18 27 31 32 37 38 42–44 mostly defining ASITN/SIR collateral grades of 3–4 and 0–2 as good and poor collaterals, respectively; 11 studies used other grading methods by DSA;12 14–16 22 25 26 33–35 39 9 studies used different grading methods on CT angiography (CTA);13 19 20 23 28 30 36 40 41 and the other studies used CT perfusion or combined grading methods with different imaging modalities 21 24 29…”

Collateral state and the effect of endovascular reperfusion therapy on clinical outcome in ischemic stroke patients

“…2013; Seeta Ramaiah et al. 2014) and yielded equivocal results. Some found a differential effect of reperfusion after EVT on clinical outcome depending on collateral status (Nambiar et al.…”

“…2013), others did not (Seeta Ramaiah et al. 2014). A compelling hypothesis in favor of an association is that good collaterals preserve the penumbra until reperfusion occurs (Miteff et al.…”

Real-Time Estimation of Core Infarct in Angiography Using Collateral Flow

“…The connection between leptomeningeal collateral flow (LMF) and survival of brain parenchyma during acute ischemia has been confirmed in a large number of clinical studies [1][2][3][4][5][6][7][8][9] . Better collateral flow is associated with smaller infarct volumes, less hemorrhagic transformation, higher recanalization rates and better clinical outcome.…”