MR CLEAN: a multicenter randomized clinical trial of endovascular treatment for acute ischemic stroke in The Netherlands.

Endovascular treatment increases the likelihood of recanalization in patients with acute ischemic stroke caused by proximal intracranial arterial occlusion. The purpose of the Multicenter Randomized Clinical trial of Endovascular treatment for Acute ischemic stroke in the Netherlands (MR CLEAN) is to assess the safety and effect on functional outcome of endovascular treatment in such patients.
DESIGN:

MR CLEAN is a pragmatic phase III multicenter randomized clinical trial with blind outcome assessment. We compare endovascular treatment (intra-arterial thrombolysis, mechanical thrombectomy or both) with no treatment, against a background of optimal medical management, which may include intravenous alteplase.
Patients should have a clinical diagnosis of acute ischemic stroke, confirmed by MRI or CT, an NIHSS score of 2 points or more, a relevant intracranial arterial occlusion, demonstrated by CTA, MRA or TCD and the possibility to start endovascular treatment within 6 hours after stroke onset.
The exact choice of endovascular treatment modality for each patient is left to the discretion of the local investigator and treating physicians. The steering committee will release recommendations and guidelines for treatment and selection of patients in the study.

STUDY OUTCOMES:

The primary outcome is the score on the modified Rankin scale 3 months after inclusion in the study. Secundary outcomes are the NIHSS score at 48 hours, vessel patency, score on the Barthel index, and the occurrence of major bleeding.
Randomization will be stratified for treatment with iv rtPA, stroke severity according to the National Institutes of Health Stroke Scale, intended mechanical thrombectomy and center. We will estimate the effect of treatment by means of the sliding dichotomy approach, which considers the whole range of the mRS. In total, 500 patients will be included.

DISCUSSION:

MR CLEAN is a pragmatic trial. Centers from other countries than the Netherlands are welcome to join the study. Inclusion of patients will take 4 years, and starts early in 2010.

The null hypothesis for this study is that endovascular treatment for acute ischemic stroke with onset of less than six hours in patients with a symptomatic intracranial proximal arterial occlusion, leads to a similar distribution of functional outcomes as standard treatment.

First patient in: april 2010.

Last patient out: July 2014.

Intra-arterial treatment (rtPA and/or mechanical thrombectomy) versus no intra-arterial treatment. The treatment is provided in addition to best medical management, including intravenous thrombolysis.