title: Stroke prevention in nonvalvular atrial fibrillation.
abstract: There has been considerable uncertainty about the best way to prevent stroke in patients with nonvalvular atrial fibrillation. Recent studies have suggested that low-dose warfarin therapy, in addition to producing fewer bleeding complications, may be as effective as higher-dose therapy in preventing thromboembolic events. Four large, prospective, randomized trials have examined the risks and benefits of warfarin therapy for stroke prophylaxis in patients with nonvalvular atrial fibrillation. All four studies showed a substantially reduced incidence of stroke and a low incidence of significant bleeding in patients treated with warfarin. One of these studies also showed that aspirin reduced the incidence of stroke. The benefits associated with long-term low-dose warfarin therapy appear to exceed the risks for serious bleeding in most patients with atrial fibrillation. Aspirin may be a viable therapeutic option for patients who are unable to take warfarin or for those in subgroups at a low risk for stroke.
authors.affiliation: Palo Alto Veterans Affairs Medical Center, CA 94304.
authors.forename: G W
authors.initials: GW
authors.lastname: Albers
authors.forename: J E
authors.initials: JE
authors.lastname: Atwood
authors.forename: J
authors.initials: J
authors.lastname: Hirsh
authors.forename: D G
authors.initials: DG
authors.lastname: Sherman
authors.forename: R A
authors.initials: RA
authors.lastname: Hughes
authors.forename: S J
authors.initials: SJ
authors.lastname: Connolly
mesh_terms: D001241:Aspirin / Q000627:therapeutic use; D001281:Atrial Fibrillation / Q000150:complications* / Q000209:etiology / Q000628:therapy; D002561:Cerebrovascular Disorders / Q000209:etiology / Q000517:prevention & control*; D006801:Humans; D015201:Meta-Analysis as Topic; D010975:Platelet Aggregation Inhibitors / Q000627:therapeutic use*; D012307:Risk Factors; D014859:Warfarin / Q000627:therapeutic use*
chemical_list: D010975:Platelet Aggregation Inhibitors; D014859:Warfarin; D001241:Aspirin