Intra-arterial therapies for acute ischemic stroke

BACKGROUND: There are no randomized trials comparing intra-arterial (IA) therapy with best medical treatment for acute ischemic stroke. To assess potential benefit from this therapeutic approach, we performed a systematic review of published IA series. Because outcome from stroke is highly dependent on baseline characteristics, we compared results against prognostic models adjusted for admission National Institute of Health Stroke Scale (NIHSS) scores and age. METHODS: We selected articles from MEDLINE and Cochrane Databases based on specified criteria that included 3-month clinical follow-up. Outcome functions from prognostic models were generated and difference from prediction calculated for each study. Best and worst mortality performers were identified and assessed for factors that distinguished them. RESULTS: We identified 27 reports with 30 treatment series representing 1,117 patients. Percent difference from predicted outcomes varied from -51 to +24.6% for mortality and -30.3 to +28.7% for good functional outcome. A mean overall difference in the percent that died compared with prediction was 0.25% (SD: ±3.5%; 95% CI: ±0.53) and in the percentage of those that achieved a good functional outcome compared with prediction was -0.15% (SD: ±2.7%; 95% CI: ±0.44). The quartile of better mortality performers relative to worst performers had a 4.8-point more severe NIHSS score at baseline (p = 0.028) and employed 50% lower doses of the most frequently used thrombolytic urokinase (p = 0.0034). CONCLUSION: We found considerable variability and lack of evidence for a net improvement in outcome after intra-arterial therapy relative to predicted natural history, substantiating the need for a prospective comparison with best medical therapy. The features associated with better performers identified here may be useful in designing such a trial.