Atrial fibrillation stroke prevention

Zabalgoitia M, et al. Transesophageal echocardiographic correlates of clinical risk of thromboembolism in nonvalvular atrial fibrillation. Stroke Prevention in Atrial Fibrillation III Investigators. J Am Coll Cardiol 1998 3 I (7) 1622-1626. 

Stroke Prevention in Atrial Fibrillation Investigators. Adjusted-dose warfarin versus low-in-tensity, fixed dose warfarin plus aspirin for high-risk patients with atrial fibrillation Stroke Prevention in Atrial Fibrillation III randomised clinical ttial. Lancet (1996) 348, 633-8,... 

Warfarin is the most commonly prescribed oral anticoagulant, with four million U.S. patients taking the drug for treatment and prevention of atrial fibrillation, stroke, deep vein thrombosis, or pulmonary embolism, and for those who have had heart valve replacement surgery. Adverse reactions to warfarin... 

Coumarin is also widely used for long-term anticoagulation in chronic atrial fibrillation (particularly to avoid cardioembolic strokes), to prevent DVT or PE in patients with chronic hypercoagulability (e.g., congenital AT or protein C deficiency), or to prevent... 

Hart RG, Halperin JL, Pearce LA, Anderson DC, Kronmal RA, McBride R, Nasco E, Sherman DG, Talbert RL, Marler JR. Lessons from the stroke prevention in atrial fibrillation trials. Ann Intern Med 2003 138 831-838. 

FIGURE 6-9. Decision algorithm for stroke prevention in atrial fibrillation.27 Risk factors for stroke prior transient ischemic attack or stroke hypertension heart failure rheumatic heart valve disease prosthetic heart valve. Target International Normalized Ratio = 2.5 (range 2 to 3). 

Warfarin has not been adequately studied in non-cardioembolic stroke, but it is often recommended in patients after antiplatelet agents fail. One small retrospective study suggests that warfarin is better than aspirin.30 More recent clinical trials have not found oral anticoagulation in those patients without atrial fibrillation or carotid stenosis to be better than antiplatelet therapy. In the majority of patients without atrial fibrillation, antiplatelet therapy is recommended over warfarin. In patients with atrial fibrillation, long-term anticoagulation with warfarin is recommended and is effective in both primary and secondary prevention of stroke.12 The goal International Normalized Ratio (INR) for this indication is 2 to 3. 

The SPAF III Writing Committee for the Stroke Prevention in Atrial Fibrillation Investigators. Patients with nonvalvular atrial fibrillation at low risk of stroke dur-... 

Kondstaal P. Anticoagulants for preventing stroke in patients with nonrheumatic atrial fibrillation and a history of stroke or transient ischemic attacks. Cochrane Database Syst Rev 1999. Issue 4. 

A major focus of drug development has been to develop orally active anticoagulants that do not require monitoring. Rivaroxiban is the first oral factor Xa inhibitor to reach phase III clinical trials. The safety and efficacy of rivaroxiban appears to be at least equivalent, and possibly superior, to LMW heparins for prevention of deep vein thrombosis no routine monitoring is required. This drug is also in clinical trials for treatment of deep vein thrombosis and prevention of stroke in atrial fibrillation. 

Stroke Prevention in Atrial Fibrillation Study Group of Investigators Special Report. N. Eng J. Med., 863 (March 22, 1990). 

Go AS, Fang MC, Singer DE. Antithrombotic therapy for stroke prevention in atrial fibrillation. Prog Cardiovasc Dis. 2005 48 108-124. 

SPORTIF III Stroke prevention in nonvalvular atrial fibrillation Open-label 36 mg twice daily for at least 12 months Warfarin, target INR, 2.0-3.0 1704 1703 (60,83)... 

Atrial fibrillation is increasing in incidence in developed countries and, because of the risk of embolic stroke, most patients require continuous anticoagulation. A large number of patients with atrial fibrillation are currently treated with vitamin K antagonists. Results of clinical trials in patients with atrial fibrillation indicate that oral direct TIs may become potential drugs for the prevention of embolic stroke and may replace warfarin (62,78,79-81). 

Olsson SB. Stroke prevention with the oral direct thrombin inhibitor ximelagatran compared with warfarin in patients with non-valvular atrial fibrillation (SPORTIF III) randomised controlled trial. Lancet 2003 362 1691-1698. 

Albers GW, Diener HC, Frison L, et al. Ximelagatran vs warfarin for stroke prevention in patients with nonvalvular atrial fibrillation a randomized trial. J Am Med Assoc 2005 293 690-698. 

Lip GY Edwards SJ. Stroke prevention with aspirin, warfarin and ximelagatran in patients with non-valvular atrial fibrillation A systematic review and meta-analysis. Thromb Res 2006 ... 

Albers GW. Stroke prevention in atrial fibrillation pooled analysis of SPORTIF III and V trials. Am J Manag Care 2004 ... 

Olsson SB, Halperin JL. Prevention of stroke in patients with atrial fibrillation. Semin Vase Med 2005 5 285-292,... 

Group TEAFTS, Secondary prevention in non-rheumatic atrial fibrillation after transient ischaemic attack or minor stroke, Lancet 1993 342(8882) 1255-1262. 

Ostermayer SH, Reisman M, Kramer PH, et al. Percutaneous left atrial appendage transcatheter occlusion (PLAATO system) to prevent stroke in high-risk patients with non-rheumatic atrial fibrillation Results from the international multi-center feasibility trials. J Am Coll Cardiol 2005 46( I ) 9-14. 

Some of the association between atrial fibrillation and stroke must be coincidental because atrial fibrillation can be caused by coronary and hypertensive heart disease, both of which may be associated with atheromatous disease or primary intracerebral hemorrhage. Although anticoagulation markedly reduces the risk of first or recurrent stroke, this is not necessarily evidence for causality because this treatment may be working in other ways, such as by inhibiting artery-to-artery embolism, although trials of warfarin in secondary prevention of stroke in sinus rhythm have shown no benefit over aspirin (Ch. 24). 

Antithrombotic therapy to prevent stroke in patients with atrial fibrillation a meta-analysis. Annals of Internal Medicine 131 492-501... 

Hart RG, Halperin JL, Pearce, LA et al. (2003). Lessons from the Stroke Prevention in Atrial Fibrillation trials. Annals of Internal Medicine 138 831-838... 

Strachan DP, Carrington D, Mendall MA et al. (1999). Relation of Chlamydia pneumoniae serology to mortality and incidence of ischemic heart disease over 13 years in the Caerphilly Prospective Heart Disease Study. British Medical Journal 318 1035-1039 Stroke Prevention in Atrial Fibrillation Investigators (1992). Predictors of thromboembolism in atrial fibrillation II Echocardiographic features of patients at risk. Annals of Internal Medicine 116 6-12 Stroke Prevention in Atrial Fibrillation Investigators (1995). Risk factors for thromboembolism during aspirin therapy in patients with atrial fibrillation the Stroke Prevention in Atrial Fibrillation Study. Journal of Stroke and Cerebrovascular Disease 5 147-157... 

Fig. 7.2. A patient presenting with atrial fibrillation and a transient ischemic attack was found to have a cerebellar microbleed on gradient echo MRI (a) and was started on stroke prevention with aspirin rather than warfarin. Six months later, this patient had a symptomatic hemorrhage at the same site (b).

Harrell FE Jr., Lee KL, Mark DB (1996). Multivariable prognostic models issues in developing models, evaluating assumptions and adequacy, and measuring and reducing errors. Statistics in Medicine 15 361-387 Hart RG (2007). Antithrombotic therapy to prevent stroke in patients with atrial fibrillation. In Treating Individuals From Randomized Trials to Personalised Medicine, Rothwell PM (ed.) pp. 265-278. London Elsevier... 

Stevens DL, Matthews WB (1973). Cryptogenic drop attacks an affliction of women. British Medical Journal 1 439-442 Stroke Prevention in Atrial Fibrillation Investigators (1995). Risk factors for... 

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