Q. Show Measurement of mitral valve?

Measurement of mitral valve and gradients across mitral valve are of importance in clinical decision making. Mitral valve area can be measured by planimetry from para sternal short axis view. Alternatively it can also be measured by different Doppler methods including continuity equation, pressure half time (PHT), and proximal isovelocity surface area methods. Mitral stenosis is considered mild if mitral valve area is >1.5 cm2 , moderate if it is between 1.1 to 1.5 cm² and severe if it is equal to or less than 1.0 cm². In patients with atrial fibrillation valve area as well as trans valvular gradients are better measured as an average of 5-10 cycles. In the presence of aortic regurgitation, ASD and non compliant left ventricle mitral valve area calculation by PHT method is fallacious. Similarly continuity equation is not applicable in the presence of mitral regurgitation. Errors in measurement are decreased if the color flow mapping is used to direct the continuous wave Doppler beam. While calculated valve area is independent of cardiac output, gradients can be erroneously low with bradycardia and low cardiac output state even in the presence of tight mitral stenosis.

Table:  Echocardiographic Score Used to Predict Outcome of Balloon Valvulopasty

Tran esophageal echocardiogram is helpful in detecting left atrial clots prior to planned balloon valvuloplasty or after an embolic event. Valve morphology can also be better assessed.