title: Atrial fibrillation.
abstract: The incidence and prevalence of atrial fibrillation are increasing because of both population ageing and an age-adjusted increase in incidence of atrial fibrillation. Deciding between a rate control or rhythm control approach depends on patient age and comorbidities, symptoms and haemodynamic consequences of the arrhythmia, but either approach is acceptable. Digoxin is no longer a first-line drug for rate control: beta-blockers and verapamil and diltiazem control heart rate better during exercise. Anti-arrhythmic drugs have only a 40%-60% success rate of maintaining sinus rhythm at 1 year, and have significant side effects. The selection of optimal antithrombotic prophylaxis depends on the patient's risk of ischaemic stroke and the benefits and risks of long-term warfarin versus aspirin, but is independent of rate or rhythm control strategy. Ischaemic stroke risk is best estimated with the CHADS2 score (Congestive heart failure, Hypertension, Age > or = 75 years, Diabetes, 1 point each; prior Stroke or transient ischaemic attack, 2 points). For patients with valvular atrial fibrillation or a CHADS(2) score > or = 2, anticoagulation with warfarin is recommended (INR 2-3, higher for mechanical valves) unless contraindicated or annual major bleeding risk > 3%. Aspirin or warfarin may be used when the CHADS(2) score = 1. Aspirin, 81-325 mg daily, is recommended in patients with a CHADS(2) score of 0 or if warfarin is contraindicated. Stroke rate is similar for paroxysmal, persistent, and permanent atrial fibrillation, and probably for atrial flutter.
authors.affiliation: Department of Cardiology, Concord Repatriation General Hospital, University of Sydney, Sydney, NSW. ben@gmp.usyd.edu.au.
authors.forename: Caroline
authors.initials: C
authors.lastname: Medi
authors.forename: Graeme J
authors.initials: GJ
authors.lastname: Hankey
authors.forename: Saul B
authors.initials: SB
authors.lastname: Freedman
mesh_terms: D000367:Age Factors; D000889:Anti-Arrhythmia Agents / Q000627:therapeutic use; D000925:Anticoagulants / Q000627:therapeutic use; D001281:Atrial Fibrillation / Q000628:therapy*; D005343:Fibrinolytic Agents / Q000627:therapeutic use; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D009200:Myocardial Contraction / Q000187:drug effects; D012307:Risk Factors; D020521:Stroke / Q000517:prevention & control
chemical_list: D000889:Anti-Arrhythmia Agents; D000925:Anticoagulants; D005343:Fibrinolytic Agents