From an anatomical perspective, the mitral valve apparatus is composed of annulus, leaflets, chords, and papillary muscles. The integration of this apparatus along with the freedom from supravalvar pathologic function (eg, supramitral ring) and left ventricular pathologic function (eg, hypoplastic ventricle) is essential for normal function. Therefore, structural abnormalities of the mitral valve causing stenosis can happen at different levels. A clinically useful system for the characterization of the anatomic types of congenital mitral valve stenosis divides it into the 4 following types: typical mitral stenosis, hypoplastic congenital mitral stenosis, supravalvar mitral stenosis, and parachute mitral valve. 3 An additional category is subvalvar stenosis, which is also known as mitral arcade. 4 The pathophysiology and resultant clinical presentation of congenital mitral stenosis are dependent on the anatomic variant, severity, associated lesions, and age. For clinical, practical, and prognostic reasons, congenital mitral stenosis can be categorized into neonatal and nonneonatal. In neonates, congenital mitral stenosis is unlikely to present as an isolated lesion; rather, it is frequently part of a “complex” or “syndrome” involving the left heart. Shone’s complex and variable degrees of hypoplastic left heart syndrome are the usual associations. Pulmonary hypertension and inadequacy of the left heart to support the systemic circulation are the most significant clinical consequences. Mitral stenosis presenting after the neonatal period is a different disease than that presenting in neonates. Children having otherwise reasonably normal hearts and mitral stenosis have already proven that their left heart is of adequate size for a biventricular arrangement. Mitral stenosis beyond infancy is more likely to be isolated. Description of the functional severity of stenosis is based on the widely accepted echocardiographic definition by the