Transcript MITRAL REGURGITATION - Al

MITRAL
REGURGITATION
2D ASSESSMENT
LOOK CAREFULLY AT THE
MITRAL VALVE APPARATUS
Tenting
HOW TO ASSESS THE
SEVERITY OF
MITRAL REGURGITATION ?
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Color flow imaging
PW Doppler
CW Doppler
Quantitative Doppler
COLOR FLOW ASSESSMENT
COLOR FLOW ASSESSMENT OF
MITRAL 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 Area
COLOR FLOW ASSESSMENT OF
MITRAL 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 MR
Posterior vs. Central Jet of MR
PW 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 - Reversal
CW Doppler Assessment of MR
• Shape: symmetrical or asymmetrical
 Chronic vs. Acute MR
• Density of signal
Quantitative Doppler
• PISA / Volumetric method
Vena Contracta, Effective Regurgitant
Orifice(ERO), Regurgitant Volume (RV)
• Continuity Equation
Effective Regurgitant Orifice(ERO),
Regurgitant Volume (RV) and Regurgitant
Fraction (RF)
Proximal Isovelocity Surface Area
(PISA)
Measurements Required
for PISA Method
•radius of flow convergence hemisphere (cm)
•aliasing velocity on color bar (cm)
•peak regurgitant velocity (cm)
•TVI of regurgitant CW jet (cm)
PISA 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 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 PISA
Severity Values for MR
ERO (mm2)
RV (cc)
< 20
< 30
Grade II - Moderate
20 – 29
30 – 44
Grade III –
Moderately severe
Grade IV - Severe
30 – 39
45 – 59
> 40
> 60
GRADE (MR)
Grade I – Mild
VENA 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 jet
How 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 Contracta
CONTINUITY EQUATION
METHOD
Measurements
Required
Normal Values
Mitral Annulus
Diameter (cm)
TVI of mitral annulus
flow (cm)
2.7 – 3.5 cm.
LVOT diameter (cm)
1.8 – 2.4 cm.
TVI of LVOT flow
(cm)
7 – 13 cm.
18 – 22 cm
CONTINUITY METHOD
• CALCULATION OF MITRAL Regurgitant
Volume (RV)
Step 1. Measure the Mitral annulus diameter
Step 2. Obtain the TVI Mann.
Step 2. Calculate the MV stroke volume
MV 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
VALUES
Normal or Trivial MR
Less than 20%
Moderate MR
30 – 50 %
Severe MR
Greater than 50%
PITFALLS in Calculation of
Regurgitant 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!