Factors influencing clinically meaningful recanalization after IV-rtPA in acute ischemic stroke

Recanalization may not result in better clinical outcomes after ischemic stroke. We determined the incidence and significant predictors of CMR, defined as CT angiographic recanalization and a good clinical outcome, after IV-rtPA in acute ischemic stroke. A CMR score was devised and tested.

One hundred twenty-six consecutive patients with anterior circulation ischemic stroke receiving IV-rtPA were retrospectively reviewed. Imaging included a baseline NCCT and CTA. Recanalization was assessed on a 24-hour CTA. Clinical outcome was determined by the 90-day mRS. CMR was defined as CTA recanalization and a good clinical outcome (mRS ≤2). Logistic regression analysis determined predictors of CMR. The predictive ability of a CMR score was tested with AIC.

CMR occurred in 29% (36/126). Patients with CMR had fewer neurologic deficits (P = .001) and higher ASPECTS (P = .041) at baseline than those without CMR. Baseline NIHSS score did not predict proximal occlusion (OR 0.959; 95% CI [0.907-1.014]; P = .141). Multivariate analysis showed admission NIHSS score (P = .001) and the site of vessel occlusion (P = .022) to be significant CMR predictors. CMR was significantly less likely in patients with proximal occlusions (ICA, P = .005; proximal M1, P = .021). A CMR score better predicted CMR than either NIHSS or vessel occlusion site alone (P < .0001).

Milder baseline stroke deficit and distal vessel occlusion are significant predictors of CMR. A combination of these parameters better predicts CMR than either parameter alone.