Thursday, January 21, 2016

MITRAL VALVE STENOSIS (my class notes)


MITRAL STENOSIS

Classic M-mode findings for Mitral Stenosis:

v Thickened mitral valve leaflets

v Decreased mitral valve E-F slope

v Anterior motion of the posterior mitral valve leaflet













Two dimensional echo finding for rheumatic MV stenosis:

v Hockey-stick appearance of the anterior mitral valve leaflet

v Increase left Atrial dimension

v Thickened MV leaflets and subvalvular apparatus

Other Two dimensional echo/Doppler finding include:

v D-shaped left ventricle

v Left Atrial thrombus

v Abnormal interventricular septal wall motion

v Increase right heart dimension

v Increased TV regurgitation jet velocity

v Increased E velocity

v Increased Pressure half-time

v Turbulent flow

MVA:  Severe stenosis = less than 1.0 cm2

            Moderate           = 1.1 to 1.5 cm2

            Mild stenosis     = 1.6 to 2.5 cm2

Normal MVA = 4 to 6 cm2

MVA (cm2) = 220/PHT (msec)

The abnormal range for PHT in patient with MV stenosis is 90 to 400 msec. MV stenosis is considered severe when PHT is 220 msec or longer.

PHT (msec) = Deceleration Time x 0.29

Mean Pressure gradient (tracing CW Doppler spectral wave form)

v Severe stenosis = more than 10 mmHg

v Moderate           = 4 to 10 mmHg

v Mild stenosis     = less than 4 mmHg

SEVERE MITRAL VALVE STENOSIS:

Ø MEAN PRESSURE GRADIENT MORE THAN 10 mmHg

Ø MITRAL VALVE AREA LESSN THAN 1.0 cm2

Ø PRESSURE HALF TIME MORE THAN 220 msec