Safety and efficacy of mechanical embolectomy in acute ischemic stroke: results of the MERCI trial.

Abstract

BACKGROUND AND PURPOSE:

The only Food and Drug Administration (FDA)-approved treatment for acute ischemic stroke is tissue plasminogen activator (tPA) given intravenously within 3 hours of symptom onset. An alternative strategy for opening intracranial vessels during stroke is mechanical embolectomy, especially for patients ineligible for intravenous tPA.

METHODS:

We investigated the safety and efficacy of a novel embolectomy device (Merci Retriever) to open occluded intracranial large vessels within 8 hours of the onset of stroke symptoms in a prospective, nonrandomized, multicenter trial. All patients were ineligible for intravenous tPA. Primary outcomes were recanalization and safety, and secondary outcomes were neurological outcome at 90 days in recanalized versus nonrecanalized patients.

RESULTS:

Recanalization was achieved in 46% (69/151) of patients on intention to treat analysis, and in 48% (68/141) of patients in whom the device was deployed. This rate is significantly higher than that expected using an historical control of 18% (P<0.0001). Clinically significant procedural complications occurred in 10 of 141 (7.1%) patients. Symptomatic intracranial hemorrhages was observed in 11 of 141 (7.8%) patients. Good neurological outcomes (modified Rankin score < or =2) were more frequent at 90 days in patients with successful recanalization compared with patients with unsuccessful recanalization (46% versus 10%; relative risk [RR], 4.4; 95% CI, 2.1 to 9.3; P<0.0001), and mortality was less (32% versus 54%; RR, 0.59; 95% CI, 0.39 to 0.89; P=0.01).

CONCLUSIONS:

A novel endovascular embolectomy device can significantly restore vascular patency during acute ischemic stroke within 8 hours of stroke symptom onset and provides an alternative intervention for patients who are otherwise ineligible for thrombolytics.

• Authors: Wade S Smith, Gene Sung, Sidney Starkman, Jeffrey L Saver, Chelsea S Kidwell, Y Pierre Gobin, Helmi L Lutsep, Gary M Nesbit, Thomas Grobelny, Marilyn M Rymer, Isaac E Silverman, Randall T Higashida, Ronald F Budzik, Michael P Marks, MERCI Trial Investigators
• Journal: Stroke (Stroke) Vol. 36 Issue 7 Pg. 1432-8 (Jul 2005) ISSN: 1524-4628 [Electronic] United States
• PMID: 15961709 (Publication Type: Clinical Trial, Journal Article, Multicenter Study, Research Support, Non-U.S. Gov't)

Chemical References

• Tissue Plasminogen Activator

Topics

• Angiography
• Brain (pathology)
• Brain Ischemia (diagnosis, pathology, surgery)
• Cerebral Hemorrhage (pathology)
• Embolectomy (methods)
• Embolism
• Follow-Up Studies
• Humans
• Multivariate Analysis
• Prospective Studies
• Regression Analysis
• Reperfusion
• Risk
• Stroke (diagnosis, surgery)
• Thrombectomy (methods)
• Thrombolytic Therapy (methods)
• Time Factors
• Tissue Plasminogen Activator (therapeutic use)
• Treatment Outcome