Atrial fibrillation and thrombo- embolism: anticoagulants or devices?

Atrial fibrillation, albeit on its own not a fatal arrhythmia, is associated with a significant risk of thrombo-embolism that may lead to disabling or fatal stroke.1 Of note, stroke still accounts for 14% of all causes of mortality in Europe.2 Thus, detection of atrial fibrillation and in turn preventive measures against thrombo-embolism are of utmost clinical importance as again outlined by the most recent ESC Guidelines.3 Importantly, the risk of thrombo-embolism must be determined in each individual patient with the CHA2DS2-VASc score4 or a growing number of other risk assessments.5 Based on risk and other characteristics of the patient, the most appropriate preventive measures should be selected. In a first two-part review article ‘Choosing a particular oral anticoagulant and dose for stroke prevention in individual patients with non-valvular atrial fibrillation’, Hans-Christoph Diener and colleagues from the University of Essen in Germany review the clinical use of antithrombotic drugs. In Part 16, the authors again remind us that patients with atrial fibrillation have a high risk of stroke and mortality, which can be considerably reduced by oral anticoagulants. Since four non-vitamin K oral anticoagulants have recently been developed and compared with warfarin in large randomized trials for the prevention of stroke and systemic embolism,7–9 physicians have a choice. They are, however. also faced with the difficult task of selecting suitable oral anticoagulants for a patient with a certain clinical profile pattern of risk factors and concomitant diseases. To address this issue, the authors analysed subgroups, such as those with coronary or peripheral artery disease, triple therapy, ablation and antiarrhythmic drug therapy, mechanical valves, and rheumatic valve disease, or only one risk factor from trials or only one episode of atrial fibrillation of vitamin K antagonists vs. non-vitamin K oral anticoagulants, for stroke prevention in atrial fibrillation, to identify those who might benefit from particular oral anticoagulants more than from others. Furthermore, as discussed in Part 2,10 the choice of oral anticoagulants may be influenced by individual clinical features or by patterns of risk factors and co-morbidities. Finally, the authors discuss the timing of initiation of anticoagulation and the use of non-vitamin K oral anticoagulant additional subgroups such as patients after stroke or transient ischaemic attack, those with acute stroke requiring thrombolysis or thrombectomy, those initiating or restarting oral anticoagulants treatment after stroke or transient ischaemic attack, with renal impairment on dialysis, with advanced age, those at high risk of gastrointestinal bleeding; and finally those with hypertension. For practising cardiologists, the authors present treatment algorithms for specific patient groups in order to help to promote optimal clinical outcomes.