Anticoagulant Management in Patients with Atrial Fibrillation

ABSTRACT

Atrial fibrillation (AF) is the most common cardiac arrhythmia and is associated with a high risk of embolic stroke (cause in 15% of all strokes and 30% of strokes in those >75 years of age). Anticoagulation with warfarin will reduce stroke risk by about two thirds. The main risks of anticoagulation, namely bleeding, can be minimized by maintaining anticoagulation control within the international normalized range range of 2.0 to 3.0 (target: 2.5). To have a public health impact, patients with AF need efficient and correct identification, with appropriate treatment directed at those patients at most risk from the condition.

KEYWORDS

Atrial fibrillation - anticoagulation - stroke risk

REFERENCES

• 1 Szekely P. Systemic embolism and anticoagulant prophylaxis in rheumatic heart disease.  BMJ. 1964;  1(5392) 1209-1212
• 2 Levine H J, Pauker S G, Salzman E W. Antithrombotic therapy in valvular heart disease.  Chest. 1989;  95(2, suppl) 98S-106S
• 3 Fleming H A, Bailey S M. Mitral valve disease, systemic embolism and anticoagulants.  Postgrad Med J. 1971;  47(551) 599-604
• 4 Wolf P A, Abbott R D, Kannel W B. Atrial fibrillation as an independent risk factor for stroke: the Framingham Study.  Stroke. 1991;  22(8) 983-988
• 5 Evans W, Swann P. Lone auricular fibrillation.  Br Heart J. 1954;  16(2) 189-194
• 6 Reid D D, Brett G Z, Hamilton P JS, Jarrett R J, Keen H, Rose G. Cardiorespiratory disease and diabetes among middle-aged male Civil Servants. A study of screening and intervention.  Lancet. 1974;  1(7856) 469-473
• 7 Rose G, Baxter P J, Reid D D, McCartney P. Prevalence and prognosis of electrocardiographic findings in middle-aged men.  Br Heart J. 1978;  40(6) 636-643
• 8 Flegel K M, Shipley M J, Rose G. Risk of stroke in non-rheumatic atrial fibrillation.  Lancet. 1987;  1(8532) 526-529
• 9 Lip G YH. Does paroxysmal atrial fibrillation confer a paroxysmal thromboembolic risk?.  Lancet. 1997;  349(9065) 1565-1566
• 10 Feinberg W M, Blackshear J L, Laupacis A, Kronmal R, Hart R G. Prevalence, age distribution, and gender of patients with atrial fibrillation. Analysis and implications.  Arch Intern Med. 1995;  155(5) 469-473
• 11 Lake F R, Cullen K J, de Klerk N H, McCall M G, Rosman D L. Atrial fibrillation and mortality in an elderly population.  Aust N Z J Med. 1989;  19(4) 321-326
• 12 Phillips S J, Whisnant J P, O'Fallon W M, Frye R L. Prevalence of cardiovascular disease and diabetes mellitus in residents of Rochester, Minnesota.  Mayo Clin Proc. 1990;  65(3) 344-359
• 13 Furberg C D, Psaty B M, Manolio T A, Gardin J M, Smith V E, Rautaharju P M. Prevalence of atrial fibrillation in elderly subjects (the Cardiovascular Health Study).  Am J Cardiol. 1994;  74(3) 236-241
• 14 Fitzmaurice D A, Hobbs F DR, Jowett S et al.. Screening versus routine practice in detection of atrial fibrillation in patients aged 65 or over: cluster randomised controlled trial.  BMJ. 2007;  335(7616) 383-386
• 15 Petersen P, Boysen G, Godtfredsen J, Andersen E D, Andersen B. Placebo-controlled, randomised trial of warfarin and aspirin for prevention of thromboembolic complications in chronic atrial fibrillation. The Copenhagen AFASAK study.  Lancet. 1989;  1(8631) 175-179
• 16 Stroke Prevention in Atrial Fibrillation Investigators . Stroke Prevention in Atrial Fibrillation Study. Final results.  Circulation. 1991;  84(2) 527-539
• 17 The Boston Area Anticoagulation Trial for Atrial Fibrillation Investigators . The effect of low-dose warfarin on the risk of stroke in patients with nonrheumatic atrial fibrillation.  N Engl J Med. 1990;  323(22) 1505-1511
• 18 Connolly S J, Laupacis A, Gent M, Roberts R S, Cairns J A, Joyner C. Canadian Atrial Fibrillation Anticoagulation (CAFA) Study.  J Am Coll Cardiol. 1991;  18(2) 349-355
• 19 EAFT (European Atrial Fibrillation Trial) Study Group . Secondary prevention in non-rheumatic atrial fibrillation after transient ischaemic attack or minor stroke.  Lancet. 1993;  342(8882) 1255-1262
• 20 Ezekowitz M D, Bridgers S L, James K E Veterans Affairs Stroke Prevention in Nonrheumatic Atrial Fibrillation Investigators et al. Warfarin in the prevention of stroke associated with nonrheumatic atrial fibrillation.  N Engl J Med. 1992;  327(20) 1406-1412
• 21 Warfarin versus aspirin for prevention of thromboembolism in atrial fibrillation: Stroke Prevention in Atrial Fibrillation II Study.  Lancet. 1994;  343(8899) 687-691
• 22 Adjusted-dose warfarin versus low-intensity, fixed-dose warfarin plus aspirin for high-risk patients with atrial fibrillation: Stroke Prevention in Atrial Fibrillation III randomised clinical trial.  Lancet. 1996;  348(9028) 633-638
• 23 Sweeney K G, Gray D P, Steele R, Evans P. Use of warfarin in non-rheumatic atrial fibrillation: a commentary from general practice.  Br J Gen Pract. 1995;  45(392) 153-158
• 24 Atrial Fibrillation Investigators . Risk factors for stroke and efficacy of antithrombotic therapy in atrial fibrillation. Analysis of pooled data from five randomized controlled trials.  Arch Intern Med. 1994;  154(13) 1449-1457
• 25 Mant J, Hobbs F DR, Fletcher K BAFTA investigators et al. Warfarin versus aspirin for stroke prevention in an elderly community population with atrial fibrillation (the Birmingham Atrial Fibrillation Treatment of the Aged Study, BAFTA): a randomised controlled trial.  Lancet. 2007;  370(9586) 493-503
• 26 Albers G W. Atrial fibrillation and stroke. Three new studies, three remaining questions.  Arch Intern Med. 1994;  154(13) 1443-1448
• 27 Gage B F, Cardinalli A B, Albers G W, Owens D K. Cost-effectiveness of warfarin and aspirin for prophylaxis of stroke in patients with nonvalvular atrial fibrillation.  JAMA. 1995;  274(23) 1839-1845
• 28 He J, Whelton P K, Vu B, Klag M J. Aspirin and risk of hemorrhagic stroke: a meta-analysis of randomized controlled trials.  JAMA. 1998;  280(22) 1930-1935
• 29 National Institute for Health and Clinical Excellence . Atrial fibrillation.  Available at: http://www.nice.org.uk/Guidance/CG36 Accessed May 4, 2009; 
• 30 Go A S, Hylek E M, Chang Y et al.. Anticoagulation therapy for stroke prevention in atrial fibrillation: how well do randomized trials translate into clinical practice?.  JAMA. 2003;  290(20) 2685-2692
• 31 van Walraven C, Hart R G, Singer D E et al.. Oral anticoagulants vs aspirin in nonvalvular atrial fibrillation: an individual patient meta-analysis.  JAMA. 2002;  288(19) 2441-2448
• 32 van Walraven C, Hart R G, Connolly S et al.. Effect of age on stroke prevention therapy in patients with atrial fibrillation: the atrial fibrillation investigators.  Stroke. 2009;  40(4) 1410-1416
• 33 Hylek E M, Skates S J, Sheehan M A, Singer D E. An analysis of the lowest effective intensity of prophylactic anticoagulation for patients with nonrheumatic atrial fibrillation.  N Engl J Med. 1996;  335(8) 540-546
• 34 Hylek E M, Singer D E. Risk factors for intracranial hemorrhage in outpatients taking warfarin.  Ann Intern Med. 1994;  120(11) 897-902
• 35 Lancaster T, Mant J, Singer D E. Stroke prevention in atrial fibrillation.  BMJ. 1997;  314(7094) 1563-1564