The CASSISS Randomized Clinical Trial

The CASSISS trial (China Angioplasty & Stenting for Symptomatic Intracranial Severe Stenosis), recently published in JAMA, is the most recent of several randomized controlled trials that have failed to show a benefit of percutaneous angioplasty and stenting over medical therapy for the prevention of stroke due to intracranial atherosclerotic stenosis. Current practice guidelines recommended that percutaneous angioplasty and stenting should not be performed routinely as a treatment for stroke prevention in patients with intracranial atherosclerotic stenosis. The CASSISS trial reinforces those recommendations and will not change practice, but it may provide some important lessons for future trial design.