Article Text

Download PDFPDF
Intra-arterial therapies for acute ischemic stroke: unsafe and without proven value
  1. William J Powers
  1. Correspondence to Dr W J Powers, Department of Neurology, University of North Carolina, 170 Manning Drive, Chapel Hill, NC 27599, USA; powersw{at}

Statistics from

Request Permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.


Intravenous tissue plasminogen activator (IV-tPA) has been demonstrated by randomized, blinded, controlled clinical trials to provide a statistically significant improvement in clinical outcome in acute ischemic stroke when administered within 4.5 h of onset to carefully selected patients.1–3 Outcomes are still poor in some eligible patients, including those with intracranial large artery thrombotic occlusions and many patients do not meet the stringent eligibility requirements.4 Intra-arterial therapies (IAT) to open large artery occlusions, both with thrombolytic drugs and mechanical devices, have been developed to address these needs. This review summarizes the current evidence for the safety and efficacy of these therapies.


All IAT carry substantial risks of causing neurological worsening. Rates of early symptomatic intracerebral hemorrhage in published studies are consistently 8–11%.5–10 These therapies cannot be considered safe when 1 in 10 patients will be worse off because of the treatment. However, they might still be clinically effective if the overall clinical benefit is sufficient to outweigh these adverse effects.

Clinical efficacy

IAT with thrombolytic drugs has been studied by randomized, controlled clinical trials with clinical endpoints as primary outcome measures. In contrast, published studies of IAT with FDA approved devices for mechanical clot extraction or dissolution have all been single arm studies with no concurrent controls and primary outcome measures based on improving angiographic findings, not clinical outcomes.

Randomized controlled clinical trials of IAT with thrombolytic drugs

There have been five randomized, controlled clinical trials of IAT with thrombolytic drugs for acute ischemic stroke: The Australian Urokinase Stroke Trial, the SYNTHESIS (Local Versus Systemic Thrombolysis for Acute Ischemic Stroke) pilot study, PROACT (Prolyse in Acute Cerebral Thromboembolism Trial) I, PROACT II and MELT (Middle Cerebral Artery Embolism Local Fibrinolytic Intervention Trial). (An additional trial did not have randomized or concealed treatment allocation.11) The Australian Urokinase Stroke Trial was a 1:1 randomized, controlled, open label, blinded follow-up trial …

View Full Text


  • Linked articles 010335.

  • Funding This work was supported by the H Houston Merritt Distinguished Professorship of Neurology at the University of North Carolina at Chapel Hill.

  • Competing interests None.

  • Provenance and peer review Commissioned; not externally peer reviewed.

Linked Articles

  • Point-Counterpoint
    Kristine A Blackham