Additional factors of thrombosis of the left atrial appendage in nonvalvular atrial fibrillation

Abstract

Aim. To study the clinical and echocardiographic parameters associated with thrombosis of the left atrial appendage (LAA) and identify independent predictors of LAA thrombosis in patients with nonvalvular atrial fibrillation (AF) before the planned catheter ablation (CA) or cardioversion. Material and methods . A retrospective data analysis of 638 patients with nonvalvular AF directed to hospitalization from 2014 to 2017 for CA or cardioversion was performed. All patients underwent clinical and instrumental examination, including transthoracic and transesophageal echocardiography (TEE). Results . According to TEE the patients were divided into 2 groups: group 1 - 44 patients (7%) with LAA thrombosis and group 2 - 594 patients (93%) without LAA thrombosis. Patients in group 1 had higher risk on CHA2DS2-VASc scale, they were more likely to have coronary artery disease, arterial hypertension, congestive heart failure (stage IIA), obesity >II class, persistent AF. Patients in both groups did not differ in anticoagulant therapy. Patients with LAA thrombosis had enlarged left atrium and right ventricle, increased right atrial volume, left ventricular (LV) end-systolic and end-diastolic diameter, higher LV myocardial mass index, lower LV ejection fraction and blood flow velocity in LAA. Using logistic regression, such independent predictors of LAA thrombosis were detected as severe obesity >II class (OR 2.75; 95% CI 1.33-5.68; p=0.006), persistent AF (OR 2.31; 95 % CI 1.07-4.99; p=0.033), increased diameter of the left atrium (OR 1.13; 95% CI 1.03-1.24; p=0.009), eccentric LV hypertrophy (OR 3.13; 95% CI 1.04-9.40; p=0.042). Conclusion. Thus, in our study we determined independent predictors of LAA thrombosis in patients with nonvalvular AF including clinical factors (obesity and persistent AF) and echocardiographic parameters (diameter of the left atrium and eccentric hypertrophy).