P381Atrial appendage thrombosis in atrial fibrillation patients treated with warfarin or direct oral anticoagulants before electrical cardioversion

Abstract

Purpose: To assess the prevalence and characteristic of left atrial appendage (LAA) and right atrial appendage (RAA) thrombi in non‐valvular atrial fibrillation (AF) patients after 4 weeks of treatment with warfarin or rivaroxaban/dabigatran before electrical cardioversion (ECV) to evaluate the duration of thrombi organization on treatment with warfarin or rivaroxaban/dabigatran to study importance of transoesophagealguided (TOE) stategy for oral anticoagulant therapy before ECV. Materials and methods: 504 patients with non‐valvular AF underwent TOE after 4 weeks of anticoagulant therapy prior to ECV in 2012‐2015 years. There were 3 anticoagulation groups: dose‐adjusted warfarin‐359 (71,2%) patients, rivaroxaban‐86 (17,0%) patients and dabigatran‐59 (11,7%) patients. ECV was performed in patients without thrombi or only after clot organization confirmed by TOE. Results: the mean age of the patients was 62621 years, and 54,2% were men. Duration of last AF episode was 1 month‐8 years. After 4 weeks of anticoagulant therapy TOE revealed LAA/RAA thrombi in warfarin group in 303 (84,4%)/11 (3,1%) patients, in rivaroxaban group in 75 (87,2%)/9 (10,5%) and in dabigatran group in 56 (94,9%)/1 (1,7%) patients, among them thrombus organization in LAA/RAA was observed in 138 (45,5%)/5 (45,5%) patients receiving warfarin, in 68 (90,6%)/6 (66,6%) patients receiving rivaroxaban and in 53 (94,6%)/1 (100%) patients receiving dabigatran, respectively. Patients with unorganized thrombi continued anticoagulant therapy and underwent TOE until revealing thrombus organization. Thus, mean duration of thrombus organization on warfarin therapy was 1066 weeks, on rivaroxaban‐564 weeks and on dabigatran‐462 weeks. Peri‐ECV thromboembolic complications were observed in 5 (1,4%) patients on warfarin therapy and in 2 (3,4%) patients on dabigatran therapy. Minor bleedings occured in 32 (8,9%) patients receiving warfarin. Conclusions: The prevalence of LAA and RAA thrombosis after 4 weeks of oral anticoagulant therapy is high treatment with rivaroxaban and dabigatran appeares to be effective and safe alternative to warfarin and allows to halve the time of thrombi organization in comparison with warfarin electrical cardioversion in effectively anticoagulated non‐valvular AF patients with organized thrombi in atrial appendages confirmed by TOE appeares to be safe.