Background: Atrial fibrillation (AF) and flutter (AFl) increase the risk of thromboembolism. The aim of the study was to assess the prevalence of left atrial thrombus (LAT) in AF/AFl in relation to oral anticoagulation (OAC). Methods: LATTEE (NCT03591627) was a multicenter, prospective, observational study enrolling consecutive patients with AF/AFl referred for transesophageal echocardiography before cardioversion or ablation. Results: Of 3109 patients enrolled, 88% were on chronic, 1.5% on transient OAC and 10% without OAC. Of patients on chronic OAC, 39% received rivaroxaban, 30% dabigatran, 14% apixaban and 18% vitamin K antagonists (VKA). Patients on apixaban were oldest, had the worst renal function and were highest in both bleeding and thromboembolic risk, and more often received reduced doses. Prevalence of LAT was 8.0% (7.3% on chronic OAC vs. 15% without OAC; p < 0.01). In patients on VKA, prevalence of LAT was doubled compared to patients on non-VKA-OACs (NOACs) (13% vs. 6.0%; p < 0.01), even after propensity score weighting (13% vs. 7.5%; p < 0.01). Prevalence of LAT in patients on apixaban was higher (9.8%) than in those on rivaroxaban (5.7%) and dabigatran (4.7%; p < 0.01 for both comparisons), however, not after propensity score weighting. Conclusions: The prevalence of LAT in AF is non-negligible even on chronic OAC. The risk of LAT seems higher on VKA compared to NOAC, and similar between different NOACs.

Introduction. Atrial fibrillation (AF) is associated with high risk of ischemic stroke. The most frequent thrombus location in AF is the left atrial appendage (LAA). Transthoracic echocardiography (TTE) is a basic diagnostic examination in patients (pts) with AF. Objectives. To analyse the relations between basic echocardiographic features, well-established stroke risk factors, type of AF, and anticoagulation therapy with the incidence of left atrial appendage thrombus (LAAT). Patients and Methods. The study group consisted of 768 pts with AF (mean age, 63 years), admitted to three high-reference cardiology departments. Five hundred and twenty-three pts were treated with non-vitamin K antagonist oral anticoagulants (NOACs) and 227 (30%) with vitamin K antagonists (VKAs). The subjects underwent TTE and transesophageal echocardiography (TEE) before cardioversion or ablation. Results. LAAT was significantly more frequent in pts with reduced left ventricular ejection fraction (LVEF): in 10.6% (7 pts) with LVEF<40% and in 9.0% (9 pts) with LVEF 40-49%, while only in 5.5% (33 pts) with LVEF>50%. Compared to pts without LAAT, those with LAAT presented with lower LVEF and higher left atrial diameter (LAD). Multivariate logistic regression revealed the following variables as independent predictors of LAAT: previous bleeding, treatment with VKA, and LVEF. Conclusion. LAAT is related to lower LVEF and higher LAD. LVEF is one of the independent predictors of LAAT. Even in the case of adequate anticoagulant therapy, it might be prudent to consider TEE before cardioversion or ablation in patients with low LVEF and LA enlargement, especially in the coexistence of other thromboembolic risk factors.

The velocity of left atrium appendage (LAA) wall motion during atrial fibrillation (AF) is a potential marker of mechanical remodelling. In this study, we investigated whether the velocity of LAA wall motion during AF predicted the success of electrical cardioversion and long-term sinus rhythm maintenance. Standard echocardiographic data were obtained by transthoracic echocardiography, and LAA wall motion velocities were measured by transoesophageal echocardiography. With logistic regression and receiver operating characteristic curve analyses, we related echocardiographic and clinical data to cardioversion outcomes and sinus rhythm maintenance at 12 months. Of 121 patients prospectively included in the study, electrical cardioversion restored sinus rhythm in 97 (81.2%), and 51 (42%) patients maintained sinus rhythm at 12 months. Patients in whom cardioversion restored sinus rhythm had higher LAA wall motion velocities than did the patients with failed cardioversions (p <0.001). Compared to patients with AF at 12 months, patients who maintained sinus rhythm had lower maximum and end-diastolic left atrial volumes (p � 0.01), lower E/e' ratios (p = 0.005), higher s' values (p = 0.013), and higher LAA motion velocities (p < 0.001). On multivariate logistic regression, only LAA wall motion velocity and E/e' ratios remained significant predictors of sinus rhythm maintenance at 12 months (p � 0.04). LAA wall motion velocity was also a significant predictor of sinus rhythm maintenance when corrected for clinical variables (p = 0.039). Conclusion: LAA wall motion velocity, as a marker of mechanical remodelling, can predict short-term and long-term sinus rhythm maintenance after electrical cardioversion in AF.

Background: Atrial fibrillation (AF) and chronic kidney disease (CKD) are associated with an increased risk of ischemic stroke. The aim of this study was to compare the clinical characteristics, the incidence of left atrial appendage (LAA) thrombus and its predictors, and spontaneous echo contrast (SEC) in a population of patients with AF depending on estimated glomerular filtration rate (eGFR) values. Methods: This study included 1962 patients who underwent transesophageal echocardiographic examination (TEE) prior to cardioversion or ablation in the years 2014-2018 in three cardiac centers. Results: More than a quarter of AF patients had decreased eGFR (< 60 mL/min/1.73 m 2) and were characterized as a high-risk population, with more comorbidities, higher thromboembolic and bleeding risk compared to those with normal renal function. Oral anticoagulation (OAC) was prescribed in 97% and 93% of patients with decreased and normal eGFR, respectively, with a higher prevalence of prescribed non-vitamin K antagonist oral anticoagulants (NOACs). The incidence of LAA thrombus (24%, 9% and 4%) and SEC (25%, 25% and 19%) increases simultaneously with a decrease in eGFR (< 30, 30-59 and > 60 mL/min/1.73 m 2 , respectively). Among patients prescribed reduced doses of NOAC, those with decreased eGFR were more often observed with LAA thrombus (10% vs. 2.5%). Non-paroxysmal AF, heart failure and previous bleeding were predictors of LAA thrombus, irrespective of eGFR value. CKD was the predictor of LAA thrombus in all patients including those with non-paroxysmal AF, males, without diabetes, without hypertension and with CHA2DS2-VASc < 2. Conclusions: Despite OAC, patients with concomitant AF and CKD remain at high risk for LAA thrombus formation.