Giant left atrium in undersized mitral ring annuloplasty.

Enlargement of left atrium occurs in patients with longstanding mitral valve disease due to chronic pressure and volume overload and occasionally left atrium reaches a massive enlargement, condition known as giant left atrium. It is most commonly associated with rheumatic mitral valve disease, both stenosis and regurgitation. This unique case deals with a 70-year-old woman who developed a giant left atrium due to a severe mitral regurgitation from complete prolapse of both mitral leaflets, as a consequence of previous undersized mitral ring annuloplasty.