Hidden problems in a case of atrial fibrillation

Atrial fibrillation (AF) is the most common cardiac arrhythmia. However, the relation between congenital heart defects and the predisposition to AF is not fully understood. A 65‐year‐old male was admitted into the emergency department due to progressive dyspnea, orthopnea, palpitations, and edema. Transthoracic echocardiogram showed bi‐atrial enlargement and dysplasia of the mitral leaflets with severe mitral regurgitation. Also, a membrane was noted in the LA, dividing the chamber into two parts, suggestive of cor triatriatum sinister. Coronary computed tomography angiography demonstrated a soft tissue septum in the left atrium. Multimodal evaluation is of vital importance for a complete approach, since, detected in time, it has an excellent prognosis.