Guidelines for the Management of Patients With Atrial Fibrillation
Transesophageal Echocardiography is the most sensitive and specific technique to detect sources and potential mechanisms for cardiogenic embolism.The technology has been used to stratify stroke risk in patients with AF and to guide cardioversion.
Several TEE features have been associated with thromboembolism in patients with nonvalvular AF, including LA/LAA thrombus, LA/LAA SEC, reduced LAA flow velocity, and aortic atheromatous abnormalities.
Although these features are associated with cardiogenic embolism, prospective investigations are needed to compare these TEE findings with clinical and transthoracic echocardiographic predictors of thromboembolism.
Detection of LA/LAA thrombus in the setting of stroke or systemic embolism is convincing evidence of a cardiogenic mechanism. TEE of patients with AF before cardioversion has shown LA or LAA thrombus in 5% to 15%, but thromboembolism after conversion to sinus rhythm has been reported even when TEE did not show thrombus. These events typically occur relatively soon after cardioversion in patients who were not treated with anticoagulation, reinforcing the need to maintain continuous therapeutic anticoagulation in patients with AF undergoing cardioversion even when no thrombus is identified.
For patients with AF of greater than 48-h duration, a TEE-guided strategy or the traditional strategy of anticoagulation for 4 wk before and 4 wk after elective cardioversion resulted in similar rates of thromboembolism (less than 1% during the 8 wk).