echocardiography in mitral stenosis
Last reviewed 01/2018
M-mode echocardiogram is diagnostic of mitral stenosis.
Mitral orifice remains open throughout diastole. There is thickening of the anterior cusp. The posterior cusp moves anteriorly (instead of posteriorly) in diastole because it is fused at the commissures with the anterior leaflet. The left atrium is dilated. The left ventricle is normal size.
The rate of left ventricular filling is slow unless there is also aortic regurgitation. The mitral orifice size is assessed with two-dimensional echocardiography.
Doppler scanning is used to assess jet velocity and therefore gradient. This demonstrates any associated mitral regurgitation but not its degree.
Transoesophageal echocardiography is used in assessing whether a stenotic mitral valve can be treated by a balloon valvotomy.
Balloon valvotomy is contraindicated if there is:
- heavy calcification of the valve
- pre-existing mitral regurgitation
- thrombus within the left atrium or left atrial appendage
- extensive scarring of the subvalvular apparatus