Introduction: The SAMMPRIS study stopped recruiting patients due to higher than expected perioperative morbidity of primary stenting in patients with symptomatic intracranial stenosis. An alternative treatment, submaximal angioplasty without stenting, performed concurrently to SAMMPRIS, may offer benefits of revascularization (improved blood flow distal to the stenosis) with lower incidence of stenting-related risks (thromboembolism, vessel dissection, reperfusion hemorrhage).

Methods: Database review identified primary submaximal angioplasty procedures performed in 41 patients for treatment of >70% intracranial stenosis associated with an acute, symptomatic ischemic event in the distribution of the diseased vessel. For results analysis, 30-day events were reported as a percentage of patients treated. One-year periprocedure and ischemic-event-free survival was reported as a percentage of all patients treated and displayed graphically with a Kaplan-Meier survival curve.

Results: Three events in 41 patients included 1 intraprocedural vessel perforation, 1 reperfusion hemorrhage <24 hours postoperatively, and 1 transient ischemic attack 3 months postprocedurally (30-day event rate 2/41, 0.49%). Median clinical follow-up duration after submaximal angioplasty was 19 months, with >1 year follow-up available for 32 patients. One-year perioperative and ischemic-event-free survival was high(29/32 patients, 91%).

Conclusions: In this series, periprocedural safety of submaximal angioplasty in the setting of acute, symptomatic atherosclerotic intracranial stenosis was demonstrated. The complication profile compares favorably with rates of identically defined event-free survival for patients randomized to medical(88%) and surgical(77%) arms of SAMMPRIS, despite absence of aggressive medical management.

Patient Care: Submaximal angioplasty offers a treatment strategy for cerebal revascularization with lower risk than primary stenting for symptomatic intracranial atherosclerotic disease. This retrospective review sets the stage for prospective analysis of this technique in this setting.

Learning Objectives: By the conclusion of the session, participants should be able to 1) understand the results of the SAMMPRIS trial, and 2) discuss options for endovascular treatment of symptomatic intracranial atherosclerosis including submaximal angioplasty

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