Angioplasty With or Without Stenting for Intracranial Artery Stenosis
Intracranial artery stenosis causes 10% of all ischemic strokes. The annual rate of recurrent vascular ischemic events is very high (20%).1,2 Angioplasty with or without stent placement is feasible; however, its safety and efficacy have not been systematically studied.
We sought to determine the efficacy and safety of angioplasty combined with best medical treatment compared with best medical treatment alone for preventing recurrent ischemic strokes, death, and vascular events in patients with ischemic stroke or transient ischemic attack resulting from intracranial artery stenosis.
We searched the Cochrane Stroke Group Trials Register (last searched March 2006), the Cochrane Central Register of Controlled Trials (CENTRAL; The Cochrane Library Issue 1, 2006), MEDLINE (1966 to March 2006), EMBASE (1980 to February 2006), and Science Citation Index (1945 to March 2006). We searched reference lists of relevant articles and contacted authors and experts in the field.
Randomized or otherwise-controlled studies comparing best medical care plus angioplasty of the intracranial cerebral arteries, with or without stent placement, with best medical care alone were included. Studies were included only if data for clinically significant end points such as recurrent ischemic stroke, hemorrhagic stroke, and death were available.
Data Collection and Analysis
Two review authors selected trials for inclusion, independently assessed trial quality, and extracted the data. Calculation of relative treatment effects with subgroup analysis was done when possible.
No randomized controlled trials were found. There were 79 articles of interest, consisting of open-label series with 3 or more cases. The overall perioperative rate of stroke was 7.9% (95% CI, 5.5% to 10.4%), the perioperative death rate was 3.4% (95% CI, 2.0% to 4.8%), and the perioperative stroke or death rate was 9.5% (95% CI, 7.0% to 12.0%). No comments can be made on the effectiveness of the procedure.
Angioplasty with or without stent placement for the prevention of stroke in patients with intracranial artery stenosis is feasible, although this procedure carries a significant morbidity and mortality risk. Evidence from randomized, controlled trials is needed to assess its safety and effectiveness in preventing recurrent territorial stroke before it is recommended for routine clinical practice.
Implications for Practice
There is insufficient evidence to recommend angioplasty of the intracranial arteries, with or without stent placement, for secondary stroke prevention in clinical practice.
Implications for Research
A controlled, clinical trial comparing angioplasty, with or without stent placement, with best medical treatment must target the population at highest risk of recurrent stroke.2 Assuming a stroke rate of 20% per year and considering the procedural complication rates from this review, a trial with an α of 0.05, power of 80%, and an expected relative risk reduction of 25% would require 950 participants per treatment arm and a perioperative rate of stroke or death of <7%. A similar trial with an expected relative risk reduction of 50% would require 220 participants per treatment arm and a perioperative rate of stroke or death <3%.
Note: The full text of this review is available in the Cochrane Library. It should be cited as follows: Cruz-Flores S, Diamond AL. Angioplasty for intracranial artery stenosis (Cochrane Review). In: The Cochrane Library, Issue 3, July 19, 2006. Oxford: Update Software. Copyright Cochrane Library, reproduced with permission.
We would like to acknowledge and thank Hazel Fraser and Brenda Thomas for their help with searching for trials and their comments.
- Received July 22, 2006.
- Accepted August 14, 2006.
Kasner SE, Chimowitz MI, Lynn MJ, Howlett-Smith H, Stern BJ, Hertzberg VS, Frankel MR, Levine SR, Chaturvedi S, Benesch CG, Sila CA, Jovin TG, Romano JG, Cloft HJ; Wafarin Aspirin Symptomatic Intracranial Disease Trial Investigators. Predictors of ischemic stroke in the territory of a symptomatic intracranial arterial stenosis. Circulation. 2006; 113: 555–563.