Grant: Project Grant

Stroke is the 3rd leading cause of death and primary cause of disability in Canada and globally. Stroke caused by narrowing of the brain arteries from cholesterol plaques is the commonest cause of stroke. Many patients with narrowing of brain arteries suffer "silent" strokes, that are only picked up by MRI scans of the brain, in addition to the diagnosed symptomatic stroke. "Silent" strokes are about four times common as symptomatic stroke and overtime lead to significant memory and gait difficulties. Currently when someone has a stroke due to narrowed arteries they are treated with aspirin, blood pressure and cholesterol-lowering medications to prevent another stroke. However even with these treatments, there is a high risk of recurrent stroke (1 in 20 chance in 30 days and 1 in 10 chance at one year) A recent study in patients with narrowing of arteries in heart and limbs that added low-dose rivaroxaban (blood thinner) to aspirin showed a 50% reduction of stroke without an increase in bleeding into the brain or fatal bleeding. We plan to assess if use of low-dose rivaroxaban and aspirin is safe (no increase bleeding into brain) in patients with stroke due to narrowing of brain arteries. The ultimate goal of this pilot study is to gather necessary information to plan for a larger study to assess for effectiveness of this combination in preventing recurrent symptomatic and "silent" strokes. If this combination is eventually confirmed to reduce stroke by 50%, it would be the biggest advance in secondary stroke prevention in the past 30 years. We will enrol 100 patients from 10 Canadian sites and randomly assign to the combination treatment (50) or aspirin (50). Patients will qualify to be in the study if they are over 40 years and has a stroke or transient ischemic attack (warning stroke) due to narrowing of the brain arteries by plaque. Patients will be followed for 2 years and have an MRI scan at the beginning and end of the study to look for "silent" strokes.