Congenital Mitral Valve Stenosis: Anatomic Variants and Surgical Reconstruction

Congenital mitral valve stenosis is a heterogeneous group of lesions that can occur as an isolated defect or, more commonly, in association with other left heart obstructive defects. Age at presentation, presence and severity of pulmonary hypertension, and location of the primary obstructing lesion have been shown to be important risk factors for survival and long-term outcomes. Anatomic features vary, and obstructing tissue or tethering structures can be present at all levels of the valve, including supra-annular, intra-leaflet, and sub-valvar. Surgical techniques aim to remove abnormal tissue that is causing the obstruction or impediment to adequate leaflet mobility, and improve the mobility of the sub-valve structures. We describe a series of surgical options for mitral valve reconstruction that address the specific pathologies frequently found in congenital mitral stenosis.