ABSTRACT
Definition Mitral stenosis (MS) refers to flow limiting constriction of the mitral valve. The orifice of a normal mitral valve is 4.0-5.0 cm2. Symptoms generally do not develop until the orifice is restricted to <2.5 cm2. Valve areas of 1.5-2.5 cm2 with mean pressure gradients <5 mmHg (0.7 kPa) are considered mild. Valve areas of 1.0-1.5 cm2 or mean pressure gradients 5-10 mmHg (0.7-1.3 kPa) are considered moderate.Valve areas of <1.0 cm2 or mean gradients >10 mmHg (1.3 kPa) are considered severe.
