Atrial fibrillation stroke

Hart RG, Palacio S, Pearce LA. Atrial fibrillation, stroke, and acute antithrombotic therapy. Analysis of randomized clinical trials. Stroke 2002 33 2722-2727. 

Lin HJ, Wolf PA, Kelly-Hayes M, Beiser AS, Kase CS, Benjamin EJ, D Agostino RB. Stroke severity in atrial fibrillation. Stroke 1996 27 1760-1764. 

Jprgensen HS, Nakayama H, Reith J, Raaschou HO, Olsen TS. Acute stroke with atrial fibrillation. Stroke 1996 27 1765-1769. 

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. 

Hylek EM, D Antonio J, Evans-Molina C, et al. Translating the results of randomized trials into clinical practice the challenge of warfarin candidacy among hospitalized elderly patients with atrial fibrillation. Stroke 2006 37(4) 1075-80. 

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... 

Expert opinion is a source, frequently elicited by survey, that is used to obtain information where no or few data are available. For example, in our experience with a multicountry evaluation of health care resource utilization in atrial fibrillation, very few country-specific published data were available on this subject. Thus the decision-analytic model was supplemented with data from a physician expert panel survey to determine initial management approach (rate control vs. cardioversion) first-, second-, and third-line agents doses and durations of therapy type and frequency of studies that would be performed to initiate and monitor therapy type and frequency of adverse events, by body system and the resources used to manage them place of treatment and adverse consequences of lack of atrial fibrillation control and cost of these consequences, for example, stroke, congestive heart failure. This method may also be used in testing the robustness of the analysis [30]. 

The Heparin in Acute Embolic Stroke Trial (HAEST) was a multicenter, randomized trial of the effect of LMWH (dalteparin 100 lU/kg sc twice daily) or aspirin (160 mg once daily) for the acute treatment of 449 patients with ischemic stroke and atrial fibrillation (AF). The primary outcome was the rate of recurrent stroke within 14 days. No difference in rates of early recurrence (8.5% dalteparin treated vs. 7.5% aspirin treated) or good 3-month functional outcome was found. The frequency of early slCH was 2.7% on dalteparin versus 1.8% on aspirin. 

Berge E, Abdelnoor M, Nakstad PH, Sandset PM, on behalf of the Haest Study Group. Low molecular-weight heparin versus aspirin in patients with acute ischemic stroke and atrial fibrillation a double blind randomised study. Lancet 2000 335 1205-1210. 

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. 

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 1449-1457. 

Atrial fibrillation leads to the development of HF, as a result of tachycardia-induced cardiomyopathy.25 Atrial fibrillation increases the risk of mortality approximately two-fold compared to that in patients without AF 23 the causes of death are likely stroke or HF. 

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). 

The electrocardiogram will determine whether the patient has atrial fibrillation, which is a major risk factor for stroke. 

Atrial fibrillation (most important and treatable cardiac cause of stroke)... 

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. 

This trace shows the volume of the left ventricle throughout the cycle. The important point is the atrial kick seen at point a. Loss of this kick in atrial fibrillation and other conditions can adversely affect cardiac function through impaired LV filling. The maximal volume occurs at the end of diastolic filling and is labelled the left ventricular end-diastolic volume (LVEDV). In the same way, the minimum volume is the left ventricular end-systolic volume (LVESV). The difference between these two values must, therefore, be the stroke volume (SV), which is usually 70 ml as demonstrated above. The ejection fraction (EF) is the SV as a percentage of the LVEDV and is around 60% in the diagram above. 

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. 

Restoration of sinus rhythm in atrial fibrillation may dislodge thrombi that have developed as a result of stasis in the enlarged left atrium. The risk of stroke and systemic arterial embolism is decreased by anticoagulation in such patients. 

Johnson CE, Lim WK, Workman BS. People aged over 75 in atrial fibrillation on warfarin the rate of major hemorrhage and stroke in more than 500 patient-years of follow-up. J Am Geriatr Soc 2005 53 655-659. 

Wolf PA, Abbott RD, Kannel WB. (1991) Atrial fibrillation as an independent risk factor for stroke the Framingham Study. Stroke 11, 983-8. 

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. 

Poller, L. and F.R.C. Path The Effect of Low Dose Warfarin on the Risk of Stroke in Patients with Nonrheumatic Atrial Fibrillation, New Eng J. Med.. 129 (July 1L 1992),... 

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

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