Intra-arterial stenting is a safe, effective treatment option for patients with acute middle cerebral artery occlusion who have contraindications to intravenous (IV) thrombolysis, according to a study published online December 11, 2012, ahead of print in Radiology. Endovascular treatment also appears to be a viable alternative after thrombolysis failure.

David Školoudík, MD, PhD, of University Hospital Ostrava (Ostrava, Czech Republic), and colleagues conducted a case-control study in 131 patients with acute ischemic stroke due to middle cerebral artery occlusion who were treated at 2 Czech centers over a 2-year period.

Within 4.5 hours of stroke onset, 75 patients received IV thrombolysis, and about a third (n = 26) required no further recanalization therapy. The remaining 49 patients, for whom the procedure failed to reopen the blocked artery within 60 minutes, received either cerebral angioplasty plus stenting (n = 23) or no additional therapy (n = 26). Patients unable to undergo IV thrombolysis were allocated to endovascular treatment within 8 hours of stroke onset (n = 31) or to no recanalization therapy (n = 25).

Favorable clinical outcome was defined as modified Rankin scale (mRS) score of 0 to 2 at 3 months after stroke onset. Stenting was more effective at producing such an outcome than no further treatment both after failed thrombolysis and in patients with contraindications to thrombolysis. Positive differences for other outcomes reached statistical significance in the contraindicated group (tables 1 and 2).

Table 1. Patients with IV Thrombolysis Failure

Abbreviations: mRs, modified Rankin scale; NIH, National Institutes of Health.

Table 2. Patients with Contraindications to IV Thrombolysis

Abbreviations: mRs, modified Rankin scale; NIH, National Institutes of Health.

Periprocedural complications occurred after stenting in 1 patient (4.3%) who failed thrombolysis and in 1 patient (3.2%) unable to receive thrombolysis. The rates of symptomatic intracranial hemorrhage at 24 hours and mortality at 7 or 90 days did not differ by treatment within either subgroup.

On multivariable analysis, baseline NIH Stroke Scale score independently predicted poor functional outcome (OR 0.854; 95% CI 0.751-0.971; P = 0.004) and complete middle cerebral artery recanalization was associated with good functional outcome (OR 5.550; 95% CI 1.477-20.851; P = 0.006).

More Comparisons Needed

In patients unable to receive IV thrombolysis, or in whom such treatment fails, “intracranial stents achieve superior outcomes,” Dr. Školoudík and colleagues conclude. “These promising clinical outcomes were seen in the setting of remarkably high rates of recanalization [and] indicate that [these patients] should be offered local revascularization therapy.”

The procedure “seems to be safe,” they note, but stress that cerebral angioplasty and stenting needs further validation in prospective randomized trials involving direct comparisons with IV thrombolysis and/or conservative treatment. In addition, the authors conclude, “studies comparing the safety and efficacy of self-[expandable] stents with self-expanding retrievable stents not requiring the use of dual antiplatelet therapy should be also performed in the future.”

Small Market for Procedure?

In a telephone interview with TCTMD, Philip M. Meyers, MD, of Columbia University Medical Center (New York, NY), called the study results “quite outstanding.”

Stroke trials demonstrate variable results because the population is so heterogeneous, Dr. Meyers continued. Still, “all of our stroke studies seem to point to the idea that early recanalization of an occluded cerebral artery is better than no or delayed recanalization,” he added. “Many patients with acute ischemic stroke present too late for effective treatment.” Dr. Meyers noted that the challenge will be to treat stroke victims early enough to make a difference.

“The upshot is that intervention appears important in carefully selected patients with acute ischemic stroke,” he concluded, stressing that identifying the proper patients for endovascular treatment remains difficult. “For instance, there are 800,000 strokes per year in the United States. Only a fraction will benefit from treatment. Which fraction and how big a fraction are the unanswered questions.”

Study Details

The cohort included 74 men and 57 women, and the mean patient age was 65.8 years. Different stents were used depending on location and local anatomic conditions: Enterprise (Cordis Neurovascular, Miami Lakes, FL); Wingspan, Gateway, Neuroform, and Wallstent (Boston Scientific, San Leandro, CA); Multilink and Acculink (Abbott Vascular, Santa Clara, CA); and Zilver (Cook Medical, Bloomington, IN).

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