Stroke: part I. A clinical update on prevention.

Clinical trials conducted during the past five years have yielded important results that have allowed us to refine our approach to stroke prevention. Treatment of isolated systolic hypertension prevents stroke and is generally well tolerated. New antiplatelet agents (clopidogrel and the combination of aspirin plus high-dose dipyridamole) have been shown to be effective in reducing vascular events in survivors of ischemic stroke, although aspirin remains the mainstay of antiplatelet therapy for stroke prevention. Several clinical trials support the benefit of lipid-lowering agents ("statins") in reducing stroke. Warfarin reduces stroke for high-risk patients with atrial fibrillation. Carotid endarterectomy is highly beneficial in reducing stroke for symptomatic patients with severe carotid stenosis (greater than 70 percent), but the benefit is less for symptomatic patients with a moderate degree of stenosis (50 to 69 percent) and for patients with asymptomatic carotid disease of any severity.