Article Text

Download PDFPDF
Understanding IMS III: old data shed new light on a futile trial
  1. Joshua A Hirsch1,
  2. R Gilberto Gonzalez2
  1. 1NeuroEndovascular Program, Massachusetts General Hospital, Boston, Massachusetts, USA
  2. 2Department of Neuroradiology, Massachusetts General Hospital, Boston, Massachusetts, USA
  1. Correspondence to Dr Joshua A Hirsch, NeuroEndovascular Program, Massachusetts General Hospital, 55 Fruit Street, Gray 241B, Boston, MA 02114, USA; hirsch{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.


Neurointerventionalists and other believers in intra-arterial thrombolysis (IAT) were disappointed to learn that the Interventional Management of Stroke (IMS) III trial was halted at a prespecified endpoint. Already there are a number of articles citing rationales for failure of bridging therapy to demonstrate what would seem like an intuitive benefit over intravenous tissue plasminogen activator (tPA) monotherapy.1 There are genuine questions relating to patient selection and device availability as to the ability of IMS III to demonstrate a positive effect. In this brief comment we explore an area not necessarily well-known to the broader neurointerventional community that might confound any bridging trial.

At the most basic level, acute ischemic stroke is caused by the lack of cerebral blood flow. This leads to neurologic dysfunction and brain tissue injury. Hence, prompt restoration of blood flow is the most logical therapeutic approach. Reperfusion remains the only proven method to treat large vessel stroke, and the criticality of recanalization is well-known to neurointerventionalists and is an active part of clinical practice.2 ,3

IMS III was a ‘bridging’ trial; patients were first treated with intravenous tPA, then randomized to mechanical recanalization versus no additional therapy. ‘Bridging’ had been shown to benefit patients.4 ,5 The rationale was to maximize chances for rapid clot lysis, restoring blood …

View Full Text


  • Funding None.

  • Competing interests None.

  • Provenance and peer review Commissioned; internally peer reviewed.