The Role of Transoesophageal Echocardiography Before Cardioversion of Atrial Fibrillation: Avoiding Overuse

Atrial fibrillation (AF) is the most common cardiac arrhythmia and remains a major cause of stroke, heart failure, hospitalization, and cardiovascular mortality. Electrical cardioversion is an effective strategy for restoring sinus rhythm in symptomatic patients; however, it carries a risk of thromboembolic complications when left atrial thrombi are present. Adequate oral anticoagulation substantially reduces this risk and has become a cornerstone of peri-cardioversion management. In this setting, transoesophageal echocardiography (TOE) represents the reference imaging modality for excluding left atrial appendage (LAA) thrombus and can facilitate early cardioversion in appropriately selected patients. However, the use of TOE varies considerably across institutions and patient populations, and its role has evolved from a potentially routine examination to a more targeted diagnostic strategy. Its main value lies in patients in whom adequate and uninterrupted anticoagulation cannot be reliably established, in those with additional factors associated with an increased likelihood of thromboembolism, or when early cardioversion is clinically desirable. Conversely, routine TOE before cardioversion in patients with well-documented, adequate, and uninterrupted anticoagulation provides limited additional benefit and may not be justified given the semi-invasive nature of the examination and the procedural resources required. This review examines the pathophysiological basis of thromboembolism associated with cardioversion, current guideline recommendations, the diagnostic performance of TOE, and its evolving role in the era of direct oral anticoagulants (DOACs), with particular emphasis on the appropriate selection of patients who may benefit from a TOE-guided cardioversion strategy.