Incidence of spontaneous echocontrast, ‘sludge’ and thrombi before cardioversion in patients with atrial fibrillation: new insights into the role of transesophageal echocardiography

Abstract

Transesophageal echocardiography (TEE)-guided cardioversion has been demonstrated to be well tolerated in patients with atrial fibrillation. Guidelines do not suggest whether patients with severe spontaneous echocontrast (SEC) and sludge can be safely submitted to cardioversion. In our observational study, we analyzed the prevalence of SEC in patients with atrial fibrillation taking different anticoagulant therapies, the incidence of embolic complications after cardioversion in patients with severe SEC or sludge and the usefulness of TEE in reducing embolic complications in these patients. The study population consisted of 1104 patients with atrial fibrillation, candidates for cardioversion and submitted to TEE. They were divided into four groups: effective conventional oral anticoagulation, short-term anticoagulation, subtherapeutic anticoagulation and effective oral anticoagulation for less than 3 weeks for different clinical reasons. Cardioversion was postponed in patients with atrial thrombosis; in the presence of severe SEC, the decision to cardiovert was left to the treating physician. Atrial thrombosis was detected in 65 (5.9%) patients, and SEC was detected in the majority of patients independent of the anticoagulant scheme; in 131 patients, it was severe and, in this group, sludge was identified in 57 patients. Cardioversion was performed in 922 patients and was successful in 849 (including 22 patients with severe SEC and four with sludge) with one minor embolic event. SEC and sludge are frequently observed in patients with atrial fibrillation undergoing cardioversion. A TEE approach may prevent the risk of embolic events. In the presence of severe SEC and sludge, treating physicians frequently postpone cardioversion, even though in the patients submitted to cardioversion, no events were observed.