Abstract T MP34: Perforator Proximity Is A Strong Independent Risk Factor For Peri-procedural Stroke In Intracranial Stenting For Atherosclerotic Disease With Aggressive Management Of Anti-platelet Therapy

Introduction: The majority of peri-procedural ischemic strokes in the SAMMPRIS trial were perforator strokes. Contemporary studies of intracranial stenting have not evaluated the proximity of atherosclerotic target lesions to major perforators. Methods: The current study evaluates a prospective aggressive anti-platelet therapy management approach at two institutions in a consecutive series of 158 patients with symptomatic intracranial atherosclerotic disease (ICAD) treated with angioplasty and stenting with self-expanding nitinol stents. Peri-procedural strokes were analyzed with respect to proximity of the target lesion to angiographically seen perforators and grouped as target lesion either within 2 mm, or greater than 2 mm from visible perforators. Results: A total of 158 patients with symptomatic ICAD were treated from 2005 to 2014. The periprocedural complication rate was 3.8% (6/158) with 1 subarachnoid hemorrhage, 0 intraparenchymal hemorrhages, 5 perforator strokes, and no stent thrombosis. With a mean follow up of 2.3 years, the total ipsilateral stroke and death rate was 6.3% (10/154). Of the 158 patients, 61 (38.6%) arteries were stented in the Middle Cerebral Artery or Basilar Artery. Twenty one of the target lesions were within 2 mm of visible perforators, and there were 4 perforator strokes (19%) in this subgroup. Forty of the target lesions were greater than 2 mm of visible perforators with one perforator stroke (2.5%) in this group. There was an approximately sevenfold higher risk of stroke with lesions within 2 mm of perforators compared to lesions greater than 2 mm in the same arteries. This was statistically significant (Fisher’s exact test, p = 0.0437). Conclusions: With aggressive monitoring and management of anti-platelet medications, intracranial stenting complications of stent thrombosis and distal emboli can be reduced, although there is still a significant risk of perforator strokes, particularly in the middle cerebral artery and basilar distributions. Target lesions within 2 mm of angiographically visualized perforators had a sevenfold higher risk for periprocedural stroke (p = 0.0437) than other lesions in the same arteries.