Atrial fibrillation predicts good functional outcome following intravenous tissue plasminogen activator in patients with severe stroke

Atrial fibrillation (AF) is associated with poor outcome after intravenous thrombolysis probably due to greater pretreatment stroke severity. We conducted this retrospective study to determine whether AF is an independent predictor for clinical outcome in patients stratified by initial stroke severity.

A total of 143 acute ischemic stroke patients who received intravenous thrombolysis within 3h after onset were enrolled. The patients were categorized according to the baseline stroke severity by National Institute of Health Stroke Scale (NIHSS) score (≤10 vs. >10) and the presence of AF or not. Favorable 90-day outcome was defined as a modified Rankin Scale (mRS) score<2.

Among the 100 patients with severe stroke (NIHSS>10), those with AF (n=52) had a higher proportion of favorable 90-day outcome than those without AF (31% vs. 8%, P=0.005). After adjustment for age, baseline glucose level, and onset to treatment time, the difference remained significant (odds ratio 5.80, 95% confidence interval 1.63-20.68). In patients with mild stroke (NIHSS≤10), no difference in clinical outcome was found between AF (n=20) and non-AF (n=23) groups.

Presence of AF was associated with favorable 90-day outcome following intravenous thrombolysis in patients with severe stroke at baseline, while the association did not exist in patients with mild stroke.