Original title: A Randomized Trial of Intraarterial Treatment for Acute Ischemic Stroke. MR CLEAN Investigators. Reference: O.A. Berkhemer et al. N Engl J Med 2015;372:11-20.

In patients undergoing acute ischemic stroke caused by a proximal intracranial artery occlusion, intraarterial endovascular treatment is effective; however, there is no evidence of clinical or functional benefits. 

This study randomized patients undergoing stroke caused by proximal occlusion of an anterior artery (confirmed by images) to intraarterial treatment plus standard treatment vs. standard treatment only. Patients were eligible if found within 6 hrs of symptom onset. 

Primary endpoint was the modified Rankin scale score at 90 days. This scale measure the functional sequel of events from cero (asymptomatic) to six (death). 

500 patients from 16 centers in The Netherlands were enrolled (233 to intraarterial treatment and 267 to standard treatment). From the total number of patients, 445 (89%) had received intravenous perfusion of alteplase prior to randomization. Retrievable stents were used in 190 of the 233 patients (81.5%) randomized to intraarterial treatment.

There was an absolute difference of 13.5 percentage points (CI 95%, 5.9 to 21.2) in the modified Rankin scale in favor of intervention (32.6% vs 19.1%). There was no significant difference in mortality or symptomatic intracranial bleeding rate.

Conclusion

In patients undergoing acute ischemic stroke caused by proximal occlusion of an anterior artery, intraarterial treatment within 6 hrs of symptom onset is safe and effective.

Editorial Comment

Similar previous studies have not shown benefits and found it difficult to enroll patients, mainly due to delayed consultation after symptoms onset. Even though study findings are positive, in 9%  of patients receiving intraarterial treatment thrombus material spread to a new territory and 13% also received carotid PCI at the time. This complexity should be taken into account when interpreting study outcomes.

SOLACI