Left atrial (LA) anomalous muscular band is a rare congenital anomaly. A 54-year-old man with persistent atrial fibrillation (AF) underwent transesophageal echocardiography (TEE) for the evaluation of LA thrombosis. On two-dimensional TEE, an abnormal linear structure was identified in the LA (Picture 1). Three-dimensional TEE clearly revealed an anomalous muscular band (Picture 2). Three-dimensional computed tomography also revealed the anomalous band connecting the LA septum to the posterior LA wall (Picture 3). The incidence of LA anomalous band is approximately 2% in autopsy cases (1). LA anomalous band is composed of fibrosis and muscular tissue and is related to patent foramen ovale and Chiari's network in origin (1). One case report showed that the anomalous band caused mitral valve prolapse (2), but no detailed echocardiographic data were available. Assessing the structure of this band is difficult, but three-dimensional TEE allows for the detailed evaluation of this rare anomaly.
Picture 1.
Picture 2.
Picture 3.
Permission for publication of the images was obtained from the patient and the institutional review board.
The authors state that they have no Conflict of Interest (COI).
References
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