CT angiography-based collateral flow and time to reperfusion are strong predictors of outcome in endovascular treatment of patients with stroke.
BACKGROUND
Collateral flow (CF) is an effective predictor of outcome in acute ischemic stroke (AIS) with potential to sustain the ischemic penumbra. However, the clinical prognostic value of CF in patients with AIS undergoing mechanical thrombectomy has not been clearly established. We evaluated the relationship of CF with clinical outcomes in patients with large artery anterior circulation AIS treated with mechanical thrombectomy.


METHODS
Baseline collaterals of patients with AIS (n=135) undergoing mechanical thrombectomy were independently evaluated by CT angiography (CTA) and conventional angiography and dichotomized into poor and good CF. Multivariable analyses were performed to evaluate the predictive effect of CF on outcome and the effect of time to reperfusion on outcome based on adequacy of the collaterals.


RESULTS
Evaluation of CF was consistent by both CTA and conventional angiography (p<0.0001). A higher rate of patients with good collaterals had good functional outcome at 3-month follow-up compared with those with poor collaterals (modified Rankin Scale (mRS) 0-2: 60% vs 10%, p=0.0001). Patients with poor collaterals had a significantly higher mortality rate (mRS 6: 45% vs 8%, p=0.0001). Multivariable analyses showed that CF was the strongest predictor of outcome. Time to reperfusion had a clear effect on favorable outcome (mRS ≤2) in patients with good collaterals; in patients with poor collaterals this effect was only seen when mRS ≤3 was considered an acceptable outcome.


CONCLUSIONS
CTA is a valid tool for assessing the ability of CF to predict clinical outcome in patients with AIS treated with mechanical thrombectomy. Limiting time to reperfusion is of definite value in patients with good collaterals and also to some extent in those with poor collaterals.
Department of Neuroscience, Comprehensive Stroke Center, University of Tor Vergata, Rome, Italy.|Santa Lucia Foundation, Rome, Italy.
Fabrizio
F
Sallustio
Department of Neuroscience, Comprehensive Stroke Center, University of Tor Vergata, Rome, Italy.|Santa Lucia Foundation, Rome, Italy.
Caterina
C
Motta
Department of Neuroscience, Comprehensive Stroke Center, University of Tor Vergata, Rome, Italy.
Silvia
S
Pizzuto
Department of Neuroscience, Comprehensive Stroke Center, University of Tor Vergata, Rome, Italy.
Marina
M
Diomedi
Department of Neuroscience, Comprehensive Stroke Center, University of Tor Vergata, Rome, Italy.
Angela
A
Giordano
Department of Neuroscience, Comprehensive Stroke Center, University of Tor Vergata, Rome, Italy.
Vittoria Carla
VC
D'Agostino
Department of Neuroscience, Comprehensive Stroke Center, University of Tor Vergata, Rome, Italy.
Domenico
D
Samà
Interventional Neuroradiology Unit, Heart and Vessels Department, Careggi University Hospital, Florence, Italy.
Salvatore
S
Mangiafico
Department of Neuroscience, Careggi University Hospital, Florence, Italy.
Valentina
V
Saia
Emergency Department, University of Tor Vergata, Rome, Italy.
Jacopo Maria
JM
Legramante
Interventional Radiology and Neuroradiology, Department of Diagnostic Imaging, University of Tor Vergata, Rome, Italy.
Daniel
D
Konda
Interventional Radiology and Neuroradiology, Department of Diagnostic Imaging, University of Tor Vergata, Rome, Italy.
Enrico
E
Pampana
Interventional Radiology and Neuroradiology, Department of Diagnostic Imaging, University of Tor Vergata, Rome, Italy.
Roberto
R
Floris
Department of Neuroscience, Comprehensive Stroke Center, University of Tor Vergata, Rome, Italy.
Paolo
P
Stanzione
Interventional Radiology and Neuroradiology, Department of Diagnostic Imaging, University of Tor Vergata, Rome, Italy.
Roberto
R
Gandini
Department of Neuroscience, Comprehensive Stroke Center, University of Tor Vergata, Rome, Italy.|Santa Lucia Foundation, Rome, Italy.
Giacomo
G
Koch
D000368:Aged; D002545:Brain Ischemia / Q000000981:diagnostic imaging / Q000601:surgery*; D002533:Cerebral Angiography / Q000379:methods / Q000639:trends*; D003097:Collateral Circulation / Q000502:physiology; D000072226:Computed Tomography Angiography / Q000379:methods / Q000639:trends*; D057510:Endovascular Procedures / Q000379:methods / Q000639:trends*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D015424:Reperfusion / Q000379:methods / Q000639:trends*; D020521:Stroke / Q000000981:diagnostic imaging / Q000601:surgery*; D013997:Time Factors; D016896:Treatment Outcome
CT Angiography; Stroke; Thrombectomy