Congenital heart diseases are broadly defined as those cardiac anomalies that are present at birth. By their very nature, such defects have their origin in embryonic development. Congenital mitral valve regurgitation is a rare disease occurring in infancy or childhood. In up to 60% of cases, congenital anomalies of the mitral valve occur in association with other cardiac lesions, and often more than one component of the mitral apparatus is involved. The true incidence of congenital mitral valve regurgitation (MVR) is difficult to determine accurately (0.21–0.42% from total mitral valve regurgitations); isolated congenital mitral regurgitation is uncommon.

The Carpentier classification of congenital mitral valve disease is the most commonly used nomenclature based on a functional analysis of the mitral valve leaflet. The contemporary anatomic classification has the advantage of minimizing observer variability in the diagnosis and it offers a much better liaison between the cardiologist and surgeon.