Ten Years of Advances in Neuroendovascular Procedures

The evolution and role of endovascular therapy for the treatment of intracranial atherosclerotic disease

Intracranial atherosclerotic disease (ICAD) is being seen as an increasingly important cause of transient ischemic attack and stroke. Attention on this disease entity has been focused as a result of two recent events: the publication of the WASID trial and the recent Food and Drug Administration approval of the Wingspan-Gateway stent system. This manuscript will review the evolution of the role of endovascular therapy in the management of ICAD. In addition, the available devices currently available for endovascular therapy will be reviewed with an eye toward peri-procedural and follow-up complication rates.

Intracranial atherosclerotic disease: an update

The consensus conference on intracranial atherosclerosis provides a comprehensive review of the existing literature relevant to the epidemiology, diagnosis, prevention, and treatment of intracranial atherosclerosis, and identifies principles of management and research priorities. Patients who have suffered a stroke or transient ischemic attack attributed to stenosis (50-99%) of a major intracranial artery face a 12 to 14% risk for subsequent stroke during the 2-year period after the initial ischemic event, despite treatment with antithrombotic medications. The annual risk for subsequent stroke may exceed 20% in high-risk groups. In patients with intracranial atherosclerotic disease, short-term and long-term anticoagulation is not superior to antiplatelet treatment. Overall, the subgroup analyses from randomized trials provide evidence about benefit of aggressive atherogenic risk factor management. Intracranial angioplasty with or without stent placement has evolved as a therapeutic option for patients with symptomatic intracranial atherosclerotic disease, particularly those with high-grade stenosis with recurrent ischemic symptoms, medication failure, or both. A multicenter randomized trial is currently under way to compare stent placement with intense medical management for patients with high-grade symptomatic intracranial atherosclerotic disease.

Intracranial atherosclerotic disease

Symptomatic intracranial arterial stenosis carries one of the highest rates of recurrent stroke (10%-20% per year) despite antithrombotic therapy. Stroke prevention strategies for intracranial atherosclerotic disease follow the guidelines for secondary stroke prevention that target atherogenic risk factors. These include following standard stroke prevention guidelines of weight loss for overweight patients, moderate physical exercise (at least 30 minutes most days), cessation of cigarette smoking, and a low-fat, low-cholesterol diet. Pharmacologic treatments include antiplatelet agents, statins, blood sugar control for diabetics, and antihypertensive medications. Goals may include low-density lipoprotein cholesterol less than 100 mg/dL (< 70 mg/dL in high-risk patients). The absolute blood pressure reduction target is uncertain, but average long-term reductions of 10/5 mm Hg are recommended. Angioplasty with stent placement for the treatment of symptomatic severe intracranial stenosis (>/= 70%) is currently being evaluated in a phase 3 randomized controlled trial. It is unclear whether angioplasty with stent placement is superior to angioplasty alone for the treatment of intracranial stenosis, so both endovascular methods are currently acceptable. Complication and success rates for intracranial angioplasty and stent placement are highly variable, so the widespread application of this procedure is generally not recommended outside of clinical trials and experienced centers.

Comparison of endovascular and surgical treatments for intracranial aneurysms: an evidence-based review

Intracranial aneurysms can be treated with endovascular or surgical techniques. We provide an objective comparison of these treatments, using data from single-centre studies, multicentre studies with and without independent outcome ascertainment, and randomised clinical trials. We compared the outcomes of patients who were candidates for endovascular treatment, surgical treatment, or both. In patients with ruptured intracranial aneurysms, rates of aneurysm obliteration were higher, and need for second treatment was lower, after surgery than after endovascular treatment. However, in observational studies and randomised trials, outcome at discharge, at 2-6 months, and at 1 year, and later survival, were all better after endovascular treatment than after surgery. The results suggest that the higher rates of incomplete obliteration and retreatment after endovascular treatment do not affect patients' clinical outcome. In observational studies of patients with unruptured intracranial aneurysms, discharge outcomes were better and hospital costs were lower after endovascular treatment than after surgery. These patients showed no difference between the two treatments in 1-year outcomes and later rebleeding, although few data were available for this comparison.