EHRA/EAPCI expert consensus statement on catheter-based left atrial appendage occlusion.

Atrial fibrillation (AF) is the most common clinically relevant cardiac arrhythmia. The estimated prevalence in the general population is 1–2% and increases with age.1–8 Patients with AF are at increased risk of thromboembolism, in particular ischaemic stroke. The risk of stroke in patients with non-valvular (essentially non-rheumatic) AF is ∼5% per year.9 Moreover, strokes related to AF are associated with a higher mortality and morbidity when compared with non-AF strokes, emphasizing the need for more effective stroke prevention in these patients.10 The CHADS2 score (cardiac failure, hypertension, age, diabetes, stroke counted double) was established to assess the risk of thrombo-embolic events in patients with AF of non-valvular origin.11 Although there is a clear relationship between the CHADS2 score and stroke rate, the CHA2DS2-VASc score has recently been introduced and adopted by the European Society of Cardiology (ESC) as well as by American Heart Association, American College of Cardiology, and Heart Rhythm Society and other national bodies’ guidelines for AF in an attempt to improve risk stratification in the low-risk group by considering additional stroke risk factors (gender, vascular disease) in addition to old factors including cardiac failure, hypertension, age (divided to two risk classes) diabetes, and stroke that may influence a decision for anticoagulation therapy.12 Prospective and randomized studies show that oral anticoagulation (OAC) significantly reduces the risk of thromboembolism.13 However, this treatment is underutilized in patients with AF due to poor patient compliance, contraindications, and potential bleeding complications.14–18 The pathogenesis of thrombogenesis in AF is multifactorial and includes the Virchow triad of events leading to thrombus formation, i.e. endothelial or endocardial damage or dysfunction, abnormal blood stasis, and altered haemostasis, platelet function, and fibrinolysis.19 There is evidence for endothelial damage, as …