Left panel shows pulse Doppler tracing with an early diastolic E wave and a late diastolic A wave (during atrial systole). In normal persons, there will be a gap between the two waves, when the atrial and ventricular diastolic pressures are equal (diastasis). Diastasis is absent in mitral stenosis as the pressures do not equalise – left atrial pressure is always higher and there is a gradient through out diastole. Mitral valve area can be estimated from the downward slope of the E wave. The slope becomes more flat as the severity of the mitral stenosis increases. The A wave is absent in atrial fibrillation.

Right panel shows two pictures, one with colour flow mapping and another without. The colour flow mapping shows the turbulent flow from left atrium to left ventricle through the stenosed mitral valve. The domed mitral leaflets in the open position with a narrow orifice is visible in the frame without colour flow mapping. Both images are in the apical four chamber view. RA: Right atrium; LA: Left atrium; LV: Left ventricle; RV: Right ventricle; MVO: Mitral valve orifice