Favorable CIS and recanalization were strong predictors of a good outcome. By using this new index as an adjunct to other criteria, the CIS may improve patient selection and help break the 50% barrier.

Background and Purpose-Although atherosclerotic plaque in the carotid and coronary arteries is accepted as a cause of ischemia, vertebral artery ostium (VAO) atherosclerotic plaque is not widely recognized as a source of ischemic stroke. We seek to demonstrate its implication in some posterior circulation ischemia. Methods-This is a nonrandomized, prospective, single-center registry on consecutive patients presenting with posterior circulation ischemia who underwent VAO stenting for significant atherosclerotic stenosis. Diagnostic evaluation and imaging studies determined the likelihood of this lesion as the symptom source (highly likely, probable, or highly unlikely). Patients were divided into 4 groups in decreasing order of severity of clinical presentation (ischemic stroke, TIA then stroke, TIA, asymptomatic), which were compared with the morphological and hemodynamic characteristics of the VAO plaque. Clinical follow-up 1 year after stenting assessed symptom recurrence. Results-One hundred fourteen patients underwent stenting of 127 lesions; 35% of the lesions were highly likely the source of symptoms, 53% were probable, and 12% were highly unlikely. Clinical presentation correlated directly with plaque irregularity and presence of clot at the VAO, as did bilateral lesions and presence of tandem lesions. Symptom recurrence at 1 year was 2%. Conclusions-Thirty-five percent of the lesions were highly likely the source of the symptoms. A direct relationship between some morphological/hemodynamic characteristics and the severity of clinical presentation was also found. Finally, patients had a very low rate of symptom recurrence after treatment. These 3 observations point strongly to VAO plaque as a potential source of some posterior circulation stroke. (Stroke. 2011;42:2544-2549.)

BACKGROUND AND PURPOSE:The WASID study established the risk of subsequent ischemic stroke at 1 year in subjects with symptomatic intracranial atherosclerotic stenosis (70%-99%) at 18%. The efficacy of different methods of endovascular revascularization in stroke prevention still has not been established. We compared the stroke rate in our registry at 1 year following intervention with the WASID results to identify which method, if any, provides the most benefit in stroke prevention. This result from the BMC-IRR follows a previously published article comparing stent placement and angioplasty outcomes.