Background: Direct-current cardioversion (DCC) for atrial fibrillation carries a risk of stroke, probably associated with the temporary atrial stunning following cardioversion. The presence of a cardiac thrombus, usually localized in the left atrial appendage (LAA), is recognized as a clear contra-indication to the cardioversion. However, the presence of atrial sludge without LAA thrombus in trans-esophageal echocardiography (TEE) remains, for many cardiologists, a relative contra-indication to the cardioversion. The aim of this study was to evaluate the safety of DCC in patients presenting atrial sludge without LAA thrombus.
Methods: We prospectively included all consecutive patients demonstrating atrial sludge without LAA thrombus in TEE and undergoing DCC for persistent atrial fibrillation (AF). Safety of DCC was evaluated by the occurrence of clinical events at 1 month following cardioversion, i.e., up to the end of the atrial stunning period, as assessed by clinical examination and the standardized and validated Questionnaire for Verifying Stroke-Free Status (QVSFS).
Results: Over a period of 2 years, 21 patients presenting atrial sludge without LAA thrombus underwent DCC for AF. During the follow-up period of 1 month after DCC, no clinical embolic event, cardiac event, or unscheduled consultations/hospitalizations occurred. At 1 month, 67% of the patients remained in sinus rhythm.
Conclusion: No clinical event occurred in patients demonstrating atrial sludge without thrombus and undergoing DCC for AF. These findings support current guidelines that only keep atrial thrombus as a contraindication to cardioversion, but warrant further investigation in large studies.
Keywords: Atrial fibrillation; Cardioversion; Sludge.