Every 15-min delay in recanalization by intra-arterial therapy in acute ischemic stroke increases risk of poor outcome

Background: Intra-arterial therapy has improved recanalization rates compared with intravenous thrombolysis for acute ischemic stroke; however, superior clinical efficacy has not been convincingly demonstrated. Time to recanalization is postulated as a mechanism hindering the efficacy of intra-arterial therapy.

Aim: To investigate the effects of time to recanalization on clinical outcome postintra-arterial therapy for acute ischemic stroke.

Methods: Clinical data were collected prospectively for consecutive patients undergoing intra-arterial therapy for acute ischemic stroke at a single center between 2009 and 2013. Ninety-day functional outcome was assessed by the modified Rankin scale. Univariate analyses identified candidate clinical variables for inclusion in the multivariable model; multivariable logistic regression analyses identified variables independently associated with good outcome, defined as modified Rankin scale 0-2.

Results: One hundred and seven patients were included in the analysis. Median (interquartile range) age was 67 (54-77) years, 41 (38%) were female, and median (interquartile range) baseline National Institute of Health Stroke Severity score was 18 (13-22). Median time from symptom onset to recanalization was 330 min (interquartile range 277-397). Fifty-four (50%) patients achieved a favorable modified Rankin scale at 90 days. Age, successful recanalization, and time to recanalization were independently associated with good outcome at 90 days in multivariable logistic regression analysis. For every 15 min delay in recanalization, the odds of good outcome decreased by 10%.

Conclusions: Longer time to recanalization was associated with poorer functional outcome post intra-arterial therapy. We recommend that a systematic approach to minimize time delay to treatment is warranted in intra-arterial therapy for acute ischemic stroke.