Ischemic stroke subtype is associated with outcome in thrombolyzed patients

Objectives The impact of ischemic stroke subtype on clinical outcome in patients treated with intravenous tissue‐type plasminogen activator ( IV ‐ tPA ) is sparsely examined. We studied the association between stroke subtype and clinical outcome in magnetic resonance imaging ( MRI )‐evaluated patients treated with IV ‐ tPA . Material and methods We conducted a single‐center retrospective analysis of MRI ‐selected stroke patients treated with IV ‐ tPA between 2004 and 2010. The Trial of ORG 10172 in Acute Stroke Treatment criteria were used to establish the stroke subtype by 3 months. The outcomes of interest were a 3‐month modified Rankin Scale score of 0–1 (favorable outcome), and early neurological improvement defined as complete remission of neurological deficit or improvement of ≥4 on the National Institute of Health Stroke Scale at 24 h. The outcomes among stroke subtypes were compared with multivariable logistic regression. Results Among 557 patients, 202 (36%) had large vessel disease ( LVD ), 153 (27%) cardioembolic stroke ( CE ), 109 (20%) small vessel disease, and 93 (17%) were of other or undetermined etiology. Early neurological improvement was present in 313 (56.4%) patients, and 361 (64.8%) patients achieved a favorable outcome. Early neurological improvement and favorable outcome were more likely in CE patients compared with LVD patients (odds ratio ( OR ), 2.1 (95% confidence interval, 1.4–3.3), and 2.0 (95% confidence interval, 1.2–3.3), respectively). Conclusions Cardioembolic stroke patients were more likely to achieve early neurological improvement and favorable outcome compared with LVD stroke following MRI ‐based IV ‐ tPA treatment. This finding may reflect a difference in the effect of IV ‐ tPA among stroke subtypes.