Effect of the Interaction between Recanalization and Collateral Circulation on Functional Outcome in Acute Ischaemic Stroke

Abstract

<jats:p> Identification of patients with acute ischaemic stroke who could most benefit from arterial recanalization after endovascular treatment remains an unsettled issue. Although several classifications of collateral circulation have been proposed, the clinical role of collaterals is still debated. We evaluated the effect of the collateral circulation in relation to recanalization as a predictor of clinical outcome. </jats:p><jats:p> Data were prospectively collected from 103 patients consecutively treated for proximal middle cerebral or internal carotid artery occlusion. The collateral circulation was evaluated with a novel semiquantitative-qualitative score, the Careggi collateral score (CCS), in six grades. Both CCS and recanalization grades (TICI) were analysed in relation to clinical outcome. A statistical analysis was performed to evaluate the effect of interaction between recanalization and collateral circulation on clinical outcome. </jats:p><jats:p> Out of the 103 patients, 37 (36.3%) had poor collaterals, and 65 (63.7%) had good collaterals. Patients with good collaterals had lower basal National Institute of Health Stroke Scale (NIHSS), more distal occlusion, smaller lesions at 24h CT scan and better functional outcome. After multivariate analysis, the interaction between recanalization and collateral grades was significantly stronger as a predictor of good outcome (OR 6.87, 95% CI 2.11–22.31) or death (OR 4.66, 95% CI 1.48–14.73) compared to the effect of the single variables. </jats:p><jats:p> Collaterals showed an effect of interaction with the recanalization grade in determining a favourable clinical outcome. Assessment of the collateral circulation might help predict clinical results after recanalization in patients undergoing endovascular treatment for acute ischaemic stroke. </jats:p>

Improving the Evaluation of Collateral Circulation by Multiphase Computed Tomography Angiography in Acute Stroke Patients Treated with Endovascular Reperfusion Therapies

“…Recent studies have shown that CC status evaluation with different techniques is a strong and independent prognostic marker for clinical outcomes after acute ischemic stroke [7,8,10,14,26,27,28]. In addition, CC status has been used to select patients for endovascular therapy [16].…”

“…The rationale for these results is the ability of CC to maintain blood flow beyond the ischemic penumbra before recanalization is achieved, reducing the infarct core and making a good clinical outcome more likely [6]. Therefore, knowledge of the degree of CC may help in the patient selection for endovascular reperfusion therapies, and improve the accuracy of imaging and clinical outcome prediction [7,8]. …”

CT perfusion and angiographic assessment of pial collateral reperfusion in acute ischemic stroke: the CAPRI study

“…Third, the actual correlation between CCS and CTP parameters remains to be elucidated because we did not use CBF to define infarct core and Tmax to delineate total hypoperfusion, as recently recommended 30. Fourth, the specific limitations of the CCS should also be considered, such as the need for a contralateral injection in the case of internal carotid artery occlusion which implies an additional delay during procedural DSA performance, lack of assessment of a potential supply from the posterior circulation and, finally, lack of a comparative assessment with other angiographic scales 12 13…”

“…The aim of this study was to evaluate the correlation between the collateral circulation, assessed with a recently proposed new angiographic score, the Careggi Collateral Score (CCS),12 13 and CTP findings in patients undergoing endovascular treatment after AIS.…”

Ischaemic stroke and ST-segment elevation myocardial infarction: fast-track single-stop approach

“…Thus, while the ischaemic penumbra corresponds to the maximum potentially salvageable brain tissue at a given point of time (moving target of interventions) the maximum tissue salvage is rarely achieved due to progressive character of IRI, and in case of intervention the risk of procedurerelated injury. In addition, the ultimate tissue salvage shall depend on modifying individual factors; foremost individually highly variable availability and efficacy of primary and secondary collaterals, 10,11 but also reactivity of brain tissue's neuro-immune-endocrine systems, pre-strokes status, ischaemic preconditioning, and topography of the lesion. 12,13 Necrotic core and ischaemic penumbra in AIS correspond to myocardial necrosis and myocardium at risk in STEMI patients.…”