The impact of arterial collateralization on outcome after intra-arterial therapy for acute ischemic stroke.
OBJECTIVE
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.


METHODS
We retrospectively analyzed patients with acute ischemic stroke with intracranial ICA and/or MCA occlusions who received intra-arterial therapy. The collaterals were graded on CTA. Univariate and multivariate analyses were used to investigate the association between the dichotomized leptomeningeal collateral score and functional outcomes at 3-months mRS ≤2, mortality, and intracranial hemorrhages.


RESULTS
Eighty-seven patients were included. The median age was 66 years (interquartile range, 54-76 years) and the median NIHSS score at admission was 18 (interquartile range, 14-20). The leptomeningeal collateral score 3 was found to have significant association with the good functional outcome at 3 months: OR = 3.13; 95% CI, 1.25-7.825; P = .016. This association remained significant when adjusted for the use of IV tissue plasminogen activator: alone, OR = 2.998; 95% CI, 1.154-7.786; P = .024; and for IV tissue plasminogen activator and other confounders (age, baseline NIHSS score, and Thrombolysis in Cerebral Infarction grades), OR = 2.985; 95% CI, 1.027-8.673; P = .045.


CONCLUSIONS
We found that poor arterial collateralization, defined as a collateral score of <3, was associated with poor outcome, after adjustment for recanalization success. We recommend that future studies include collateral scores as one of the predictors of functional outcome.
From the Melbourne Brain Centre (S.S.R., B.Y.).
S
S
Seeta Ramaiah
L
L
Churilov
P
P
Mitchell
R
R
Dowling
B
B
Yan
D000368:Aged; D015901:Angiography, Digital Subtraction; D002545:Brain Ischemia / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000628:therapy; D002343:Carotid Artery, Internal / Q000000981:diagnostic imaging; D002533:Cerebral Angiography; D003097:Collateral Circulation; D005260:Female; D005343:Fibrinolytic Agents / Q000627:therapeutic use; D006801:Humans; D007269:Injections, Intra-Arterial; D008297:Male; D008578:Meninges / Q000098:blood supply; D008875:Middle Aged; D020768:Middle Cerebral Artery / Q000000981:diagnostic imaging; D012189:Retrospective Studies; D020521:Stroke / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000628:therapy; D015912:Thrombolytic Therapy / Q000379:methods*; D010959:Tissue Plasminogen Activator / Q000627:therapeutic use; D016896:Treatment Outcome
D005343:Fibrinolytic Agents; D010959:Tissue Plasminogen Activator