Rare cardiac outpouching in rheumatic mitral valve disease

A woman in her 40s with a decade-old history of exertional dyspnoea and palpitations presents with a long pansystolic murmur at the cardiac apex. Chest X-ray reveals cardiomegaly. Two-dimensional transthoracic echocardiography shows severe mitral regurgitation with an outpouching from the left atrium. The image obtained from the apical four-chamber window is shown in ( figure 1). Colour Doppler of the mitral valve was also obtained from the apical four-chamber window (figure 2). CT angiography confirms the left atrial outpouching (figure 3). She undergoes mitral valve replacement and excision of the outpouching (figure 4).