mitral regurgitation. 2d assessment look carefully at the mitral valve apparatus

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MITRAL MITRAL REGURGITATION REGURGITATION

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MITRAL MITRAL REGURGITATIONREGURGITATION

2D ASSESSMENT2D ASSESSMENT

LOOK CAREFULLY AT THE LOOK CAREFULLY AT THE MITRAL VALVE APPARATUSMITRAL VALVE APPARATUS

Tenting Tenting

HOW TO ASSESS THE HOW TO ASSESS THE SEVERITYSEVERITY OF OF

MITRAL REGURGITATION ?MITRAL REGURGITATION ?

• Color flow imaging

• PW Doppler

• CW Doppler

• Quantitative Doppler

COLOR FLOW ASSESSMENTCOLOR FLOW ASSESSMENT

COLOR FLOW ASSESSMENT OF COLOR FLOW ASSESSMENT OF MITRAL REGURGITATIONMITRAL REGURGITATION

• JET AREA

- central jet <4cm2 or <20% of LA area = mild MR

- >40% of LA area and reaches the posterior wall of LA = severe MR

MR by Regurgitant Jet AreaMR by Regurgitant Jet Area

COLOR FLOW ASSESSMENT OF COLOR FLOW ASSESSMENT OF MITRAL REGURGITATIONMITRAL REGURGITATION

• JET SHAPE AND DIRECTION

- central, eccentric or wall jet

ex. Ab(N) in Posterior leaflet – anteriorly directed jet

Ab(N) in Anterior leaflet – posteriorly directed jet

Dilatation of LV or Mitral Annulus - central,

symmetric regurgitant jet

ANTERIORLY Directed MRANTERIORLY Directed MR

Posterior vs. Central Jet of MRPosterior vs. Central Jet of MR

PW Doppler Assessment of MRPW Doppler Assessment of MR

• Mitral Inflow – velocity increases with severe MR

“E” velocity >1.5 m/sec

• Pulmonary vein flow – systolic flow reversal in severe MR

PV FLOW - ReversalPV FLOW - Reversal

CW Doppler Assessment of MRCW Doppler Assessment of MR• Shape: symmetrical or asymmetrical

Chronic vs. Acute MR

• Density of signal

Quantitative DopplerQuantitative Doppler

• PISA / Volumetric methodVena Contracta, Effective Regurgitant

Orifice(ERO), Regurgitant Volume (RV)

• Continuity EquationEffective Regurgitant Orifice(ERO),

Regurgitant Volume (RV) and Regurgitant Fraction (RF)

Proximal Isovelocity Surface Area Proximal Isovelocity Surface Area (PISA)(PISA)

Measurements Required Measurements Required for PISA Methodfor PISA Method

•radius of flow convergence hemisphere (cm)radius of flow convergence hemisphere (cm)

•aliasing velocity on color bar (cm)aliasing velocity on color bar (cm)

•peak regurgitant velocity (cm)peak regurgitant velocity (cm)

•TVI of regurgitant CW jet (cm)TVI of regurgitant CW jet (cm)

PISA MethodPISA Method

• Shift color baseline in direction of flow

MR ↓

• Aliasing velocity will vary (20-40cm) ideal: an aliasing velocity that creates a

hemispheric shape

• Measure the radius (r) in mid-late systole {peak MR velocity} and take note of the aliasing velocity (Va)

PISA MethodPISA Method• Using CW doppler, obtain optimal

regurgitant jet• Measure peak regurgitant velocity (V)• Trace regurgitant VTI

PISA Calculation:

Flow (cc/sec) = 6.28 x [r (cm.)2] x Va (cm/sec)ERO (cm2) = Flow (cc/sec) V (cm/sec)RV (cc) = ERO (cm2) x VTI (cm)

MR by PISAMR by PISA

Severity Values for MRSeverity Values for MR

GRADE (MR) ERO (mm2) RV (cc)

Grade I – Mild < 20 < 30

Grade II - Moderate 20 – 29 30 – 44

Grade III – Moderately severe

30 – 39 45 – 59

Grade IV - Severe > 40 > 60

VENA CONTRACTAVENA CONTRACTA• physiologic or effective orifice area of regurgitant jets• have an advantage with PISA for eccentric jets because

it is affected less by the eccentricity of the jetHow to obtain:• Optimize color flow imaging of the regurgitant jet by

demonstrating the PISA, Vena contracta and regurgitant jet.

• Magnify the region of interest with zoom or regional expansion selection.

• Acquire the image using the cine-loop format.• Measure the smallest width immediately distal to the

regurgitant orifice, perpendicular to the direction of the jet.

Vena ContractaVena Contracta

CONTINUITY EQUATION CONTINUITY EQUATION METHODMETHOD

Measurements Required

Normal Values

Mitral Annulus Diameter (cm)

2.7 – 3.5 cm.

TVI of mitral annulus flow (cm)

7 – 13 cm.

LVOT diameter (cm) 1.8 – 2.4 cm.

TVI of LVOT flow (cm)

18 – 22 cm

CONTINUITY METHODCONTINUITY METHOD• CALCULATION OF MITRAL Regurgitant

Volume (RV)Step 1. Measure the Mitral annulus diameterStep 2. Obtain the TVI Mann.

Step 2. Calculate the MV stroke volumeMV inflow volume(cc)= (MAnn. dia.)2 x 0.785 x TVI MAnn.

Step 3. Measure the LVOT diameter.

Step 4. Obtain the TVILVOT.Step 5. Calculate the AV stroke volume AV outflow volume(cc)= (LVOT dia.)2 x 0.785 x TVI LVOT.

Step 6. Determine the Mitral RV

RV (cc) = MV inflow volume(cc) – AV outflow volume (cc)

Step 7. Calculate the ERO ERO = RV

VTI MR

• Calculation of Mitral Regurgitant Fraction (RF)

Step 8. Calculate the MV RF.

RF(%) = Mitral RV(cc) x 100

MV inflow volume (cc)

REGURGITANT FRACTION REGURGITANT FRACTION VALUESVALUES

Normal or Trivial MR Less than 20%

Moderate MR 30 – 50 %

Severe MR Greater than 50%

PITFALLS in Calculation of PITFALLS in Calculation of Regurgitant Volume / FractionsRegurgitant Volume / Fractions

1. Learning curve of the operator

2. Significant Doppler angle (more than 200) may lead to underestimation of velocity and TVI. Optimal: parallel to bld.flow

3. Incorrect placement of sample volume.

4. Not averaging enough measurements.

5. Incorrect measurement of Annulus diameters.

6. Formula is invalid if multivalvular regurgitant lesions or significant shunts present.

THANK YOU!