The Pros and Cons of Brain Stents for Stroke Patients

June 4, 2015

Two studies show that stroke patients are more likely to recover when blood flow to the brain is restored by stents that remove the clots that are causing damage.

Brain stents show promise for certain, but not all, stroke patients.

Two studies show that stroke patients are more likely to recover when blood flow to the brain is restored by stents that remove the clots that are causing damage. Both studies were stopped early after demonstrating overwhelming benefits for the patients who underwent clot removal. 

The studies were simultaneously presented at the International Stroke Conference in Nashville, TN, and published in The New England Journal of Medicine earlier this year.

A report led by Canadian researchers found that rapid endovascular treatment improved functional outcomes and reduced mortality. The authors noted that up to 80% of patients with a proximal vessel occlusion in the anterior circulation die within 90 days after stroke onset or do not regain functional independence despite alteplase treatment. They evaluated rapid endovascular treatment in addition to standard care in patients with acute ischemic stroke with a small infarct core, a proximal intracranial arterial occlusion, and moderate-to-good collateral circulation.

The researchers enrolled 316 patients from 22 centers worldwide, including 238 who received intravenous alteplase. They randomly assigned 118 patients to receive standard care or 120 patients to standard care plus endovascular treatment with the use of available thrombectomy devices.

After 3 months, 53% of patients undergoing clot retrieval were functionally independent as compared with 29% of those given only drugs. Deaths also were lower (10%) with thrombectomy as compared with standard care (19%).

In the second study, Australian and New Zealand researchers randomly assigned 70 patients with ischemic stroke who were receiving alteplase less than 4.5 hours after the onset of ischemic stroke to either undergo endovascular thrombectomy with the Solitaire FR (Flow Restoration) stent retriever (35 patients) or to continue receiving alteplase alone (35 patients).

The surgical procedure restored blood flow to the brain in all patients, while drug therapy did so for only 37% of patients. After 3 months, thrombectomy led to neurological improvement in 71% of patients as compared with 40% of those on medical therapy.

Balloon Stents Contraindicated for Intracranial Stenosis

For patients with intracranial stenosis, one of the most common etiologies of stroke, a balloon-expandable stent may not be the appropriate treatment, according to an international, multicenter, randomized, parallel group trial.

The researchers randomized patients with symptomatic intracranial stenosis to receive treatment with a balloon-expandable stent plus medical therapy (59 patients) or medical therapy alone (53 patients). Enrollment was halted after negative results from another trial prompted an early analysis of outcomes. 

Intracranial hemorrhage within 30 days occurred in more patients in the stent group (8.6%) as compare to none in the medical group. The 1-year primary outcome of stroke or hard transient ischemic attack occurred in more patients in the stent group (36.2%) versus the medical group (15.1%). Twice as many patients in the stent group (24.1%) had a worsening of baseline disability score as in the medical group (11.2%).

The researchers concluded that these findings do not support the use of a balloon-expandable stent for patients with symptomatic intracranial arterial stenosis.