Introduction

Patients with atrial flutter (AFL) are at risk of stroke; however, the stratification of stroke risk is difficult. It remains unknown whether left atrial appendage thrombus (LAAT) in AFL patients on chronic oral anticoagulation (OAC) contributes significantly to that risk.

Aim of the research

To assess the prevalence and predictors of LAAT, and its role in the prediction of mortality, stroke, and systemic thromboembolic events among consecutive AFL patients on OAC admitted for electrical cardioversion.

Material and methods

This was a prospective, single-centre cohort study. The participants underwent transoesophageal echocardiography before electrical cardioversion. A total of 69 patients were enrolled. The primary outcome was the presence of LAAT. All participants were followed up for 12 months to evaluate the incidence of systemic thromboembolic events, stroke, and death.

Results

Despite uninterrupted OAC, irrespective of the anticoagulant agent type, LAAT was present in 10.1% of patients referred for cardioversion due to typical AFL of > 48-hour duration. The significant predictor of LAAT was prior stroke/transient ischaemic attack/thromboembolic event (OR = 14.75; 95% CI: 2.17–108.33). No deaths, strokes, or systemic thromboembolic events occurred during the follow-up period.

Conclusions

The predictive role of LAAT in relation to mortality, stroke, and systemic thromboembolic events among patients with AFL and chronic oral anticoagulation remains unclear.