Aims Guideline-adherent therapy for stroke prevention in atrial fibrillation has been associated with better outcomes, in terms of thromboembolism (TE) and bleeding. Methods and results In this report from the EuroObservational Research Programme-Atrial Fibrillation (EORP-AF) Pilot General Registry, we describe the associated baseline features of 'high risk' AF patients in relation to guideline-adherent antithrombotic treatment, i.e. whether they were adherent, over-treated, or under-treated based on the 2012 European Society of Cardiology (ESC) guidelines. Secondly, we assessed the predictors of guideline-adherent antithrombotic treatment. Thirdly, we evaluated outcomes for all-cause mortality, TE, bleeding, and the composite endpoint of 'any TE, cardiovascular death or bleeding' in relation to whether they were ESC guideline-adherent treatment. From the EORP-AF cohort, the follow-up dataset of 2634 subjects was used to assess the impact of guideline adherence or non-adherence. Of these, 1602 (60.6%) were guideline adherent, whilst 458 (17.3%) were under-treated, and 574 (21.7%) were over-treated. Non-guideline-adherent treatment can be related to region of Europe as well as associated clinical features, but not age, AF type, symptoms, or echocardiography indices. Over-treatment per se was associated with symptoms, using the EHRA score, as well as other comorbidities. Guideline-adherent antithrombotic management based on the ESC guidelines is associated with significantly better outcomes. Specifically, the endpoint of 'all cause death and any TE' is increased by >60% by undertreatment [hazard ratio (HR) 1.679 (95% confidence interval (CI) 1.202-2.347)] or over-treatment [HR 1.622 (95% CI 1.173-2.23)]. For the composite endpoint of 'cardiovascular death, any TE or bleeding', over-treatment increased risk by.70% [HR 1.722 (95% CI 1.200-2.470)]. Conclusion Even in this cohort with high overall rates of oral anticoagulation use, ESC guideline-adherent antithrombotic management is associated with significantly better outcomes, including those related to mortality and TE, as well as the composite endpoint of 'cardiovascular death, any TE or bleeding'. These contemporary observations emphasize the importance of guideline implementation, and adherence to the 2012 ESC guidelines for stroke prevention in AF.
- Atrial fibrillation