Transesophageal Echocardiography for Patients with Atrial Fibrillation

Abstract

Atrial fibrillation is the most common sustained arrhythmia. For patients presenting with their first episode of atrial fibrillation, transthoracic echocardiography is often helpful for initial management and evaluation. Many cardiac disorders associated with atrial fibrillation, including mitral valve disease, hypertensive heart disease [left ventricular (LV) hypertrophy], or focal ischemic heart disease (segmented LV systolic dysfunction) may be recognized by transthoracic echocardiography. The absence of both clinical risk factors and structural heart disease in transthoracic echocardiography identifies patients for whom chronic therapy with aspirin as opposed to warfarin may be preferred. Transthoracic echocardiography is not advocated for identification or exclusion of atrial thrombi because of its inability to detail small thrombi and to image the left atrial appendage. For the detection of left atrial thrombi, transesophageal echocardiography (TEE) is superior. The author recommends cardioversion for most patients who present with their first episode of atrial fibrillation (assuming the duration of the atrial fibrillation is brief, and reversible potential causes of atrial fibrillation have been treated). Patients with persistent atrial fibrillation of more than 1 year and those with a left atrial dimension of more than 6.0 cm are less likely to have long-term maintenance of sinus rhythm. Patients with atrial fibrillation for at least 2 days have a 6% risk of cardioversion-related clinical thromboembolism if cardioversion is not preceded by 3 to 4 weeks of warfarin. Transesophageal echocardiography may be beneficial in guiding early cardioversion and detecting left atrial thrombi. Systemic anticoagulation for 4 weeks after cardioversion inhibits the formation of new thrombi during the recovery of atrial function, and can be used for prophylaxis should the patient revert to atrial fibrillation. The presence of an atrial thrombus by TEE confers an adverse prognosis despite maintenance of systemic anticoagulation and avoidance of cardioversion. KeywordsAtrial FibrillationInternational Normalize RatioSinus RhythmTransesophageal EchocardiographyLeft Atrial AppendageThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.