[Preventing cerebrovascular accidents during atrial fibrillation]. / Prévention des accidents vasculaires cérébraux dans la fibrillation auriculaire.

ABSTRACT

Atrial fibrillation, the most commonly encountered arrhythmia in clinical practice, is associated with substantial morbidity and mortality. Its incidence and prevalence are increasing, and it represents a growing clinical and economic burden. Recent research has highlighted new approaches to both pharmacological and non-pharmacological management. Pooled data from trials comparing antithrombotic treatment with placebo show that warfarin reduces the risk of stroke by 62% and that aspirin alone reduces the risk by 22%. Overall, in high-risk patients, warfarin was better than aspirin in preventing strokes, with a relative risk reduction of 36%, but the risk of major hemorrhage with warfarin was twice that with aspirin. Anticoagulation treatment needs to be tailored individually for patients on the basis of age, comorbidities, and contraindications. However, warfarin remains under-prescribed in clinical practice, for reasons related to patients (comorbidities) and physicians. The limitations of warfarin treatment have prompted the development of new anticoagulants with predictable pharmacokinetics that do not require as frequent monitoring. Ximelagatran, an oral direct thrombin inhibitor, was compared with warfarin in the SPORTIF program, which found both agents to be broadly effective in the prevention of embolic events, but observed abnormal liver function tests in 6% of patients on ximelagatran. Liver function monitoring during treatment is thus needed. Idraparinux, a factor Xa inhibitor administered by once weekly subcutaneous injections, is being evaluated in patients with atrial fibrillation. The ACTIVE trial is currently assessing the role of aspirin plus clopidogrel, compared with adjusted dose warfarin, in the prevention of vascular events in high-risk patients with atrial fibrillation. Angiotensin-converting enzyme inhibitors and angiotensin II receptor-blocking drugs interfere with atrial remodeling and show promise in atrial fibrillation, as suggested in the LIFE trial. Preliminary studies suggest that statins may reduce the risk of recurrence after electrical cardioversion. Finally, percutaneous methods for occlusion of the left atrial appendage are currently under investigation in patients at high risk of thromboembolism but with contraindications for chronic warfarin.