Factors that Contribute to the Failure of Thromboprophylaxis in Patients with Atrial Fibrillation: A Hospital-Based Cross-Sectional Study

Background: Currently, there is a paucity of data on the reasons for the occurrence of thromboembolic events in patients with atrial fibrillation (AF). This study attempted to unravel the factors contributing to the failure of stroke prevention in AF patients. Subjects and Methods: This single-center, cross-sectional study prospectively enrolled patients with non-valvular AF with a history of thromboembolism from January 2017 to September 2021. Data on clinical characteristics, awareness of AF diagnosis, use of oral anticoagulants (OACs) prior to the first thromboembolic event, and reasons for either non-use or discontinuation of OACs were collected through a questionnaire survey administered to the patients or their family members. The index date was defined as the date of the first thromboembolic event. Results: Based on the patients’ awareness of their AF diagnosis prior to the index date, they were categorized into two groups: Group A ( n = 309), consisting of those who were unaware of their diagnosis, and Group B ( n = 443), consisting of those who were aware. Of the 402 patients in Group B who were at high risk of stroke before the index date, 75.9% (305/402) had never received anticoagulant therapy. The primary reason for this was that patients were not informed about the elevated risk of stroke associated with AF. Another 24.1% (97/402) of them had ever been treated with OACs, but 43.3% (42/97) of them had already discontinued OACs, for which minor bleeding was the most common factor (15/42). Of the 55 patients who continuously received anticoagulation therapy, 33 received the inappropriate treatment of OACs. Conclusions: This study revealed that the major factors contributing to the failure of stroke prevention in patients with AF included unawareness of AF diagnosis, unawareness of stroke risk due to AF, discontinuation of OACs due to minor bleeding, and inappropriate use of OACs. Measures should be taken to increase patient and physician awareness of AF and AF-related stroke risk.