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How to Evaluate Valvular Stenosis and Regurgitation: What

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How to Evaluate
Vavlvular Stenosis
and Regurgitation:
What Numbers
Really Matter
Margaret Park, BS, RVT, RDCS,
FASE
How to Evaluate Valvular
Stenosis and Regurgitation:
What Numbers Really Matter
Margaret M. Park, BS, RVT, RDCS, FASE
Cleveland Clinic
Heart and Vascular Institute
Objectives
As a result of this presentation, the attendee should be able to:
1.
2.
3.
4.
5.
Apply a logical approach to imaging patients with valvular
stenosis and regurgitation.
Describe the various quantitative parameters that can be obtained
by 2D Doppler echocardiography in the evaluation of valve
stenosis and/or regurgitation.
Discuss parameters useful for the quantification of valvular
regurgitation such as aortic pressure half time and aortic flow
reversal.
Implement the proximal flow convergence method and understand
how it can be simplified.
Apply technical tips to your everyday analysis of valvular disease.
ASE Guidelines and Standards
Echocardiographic Assessment of Valve
Stenosis: EAE/ASE Recommendations for
Clinical Practice, Baumgartner et al,
Journal American Society of
Echocardiography, January 2009
ase@asecho.org
ASE Guidelines and Standards
Recommendations for the Evaluation of
the Severity of Native Valvular
Regurgitation with Two-dimensional and
Doppler Echocardiography, Zoghbi et al,
Journal American Society of
Echocardiography 2003;16:777-802
ase@asecho.org
Evaluation of Valvular Stenosis
Narrowing of the valve orifice
• Aortic valve stenosis (AS)
• Pulmonic valve stenosis (PS)
• Mitral valve stenosis (MS)
• Tricuspid valve stenosis (TS)
Evaluation of Valvular Stenosis
•
•
•
•
•
Thickening/calcification
Restricted leaflet mobility(opening)
Underlying etiology
Comprehensive Doppler exam
Utilize ALL available Doppler
windows
Evaluation of Valvular Stenosis
•
•
•
•
•
•
Correct measurement requires
parallel beam alignment to flow
Accurate pressure gradients depend
on accurate velocity data
Bernoulli equation (modified)
Pressure gradient = 4 x V2
Imaging Probe/color flow Doppler
Non-imaging probe
Aortic Valve stenosis
•
Determine etiology
• Degenerative – senile
• Congenital – bicuspid aortic valve
• Rheumatic – (post inflammatory)
• Classification – level of obstruction
• Valvular
• Subvalvular
• Supravalvular
Aortic Valve Stenosis
2D Evaluation
• Number of cusps
• Thickness and calcification
• Leaflet mobility
• Cooptation lines, Y, inverted
Mercedes Benz sign
• LV function
• Other valve abnormalities
Aortic valve stenosis
Echo-Doppler assessment
• Maximal Velocity Gradient
• Mean Velocity Gradient
• Valve area (continuity Equation)
• LVOT diameter
• LVOT velocity
Measurement of LVOT diameter
Image modified from ASE Guidelines and standards;
Echocardiographic Assessment of Valve Stenosis:
EAE/ASE Recommendations for Clinical Practice ,
Baumgartner et al
Repeat three times
and use the largest
diameter
•Inner edge to inner
edge
•Septum to MV leaflet
•Parallel to AV
•.5 - 1.0 cm from valve
Pulsed wave (PW) of LVOT
Image modified from ASE Guidelines and standards;
Echocardiographic Assessment of Valve Stenosis:
EAE/ASE Recommendations for Clinical Practice ,
Baumgartner et al
Place sample
volume(SV) at same
point as diameter
measurement
•Apical 5 chamber or
long axis views
•Avoid high PRF
•Laminar flow curve
•Low wall filter
Doppler Peak or maximum
Continuous wave (CW) jet velocity
CW, suprasternal notch
Use all available
windows, align jet
parallel to flow
•Apical
•Right sternal
border
•Suprasternal notch
•Subcostal
Aortic valve Area (AVA)
Continuity Equation - simplified
•
•
•
AVA = CSA (LVOT) x TVI (LVOT) / TVI (AS)
CSA = 3.14 x r2
Radius (r) = ВЅ measured diameter (radius
is squared to determine area)
Area = CSA (LVOT) x V (LVOT) / V (AS)
Area = cm2
AVA Calculation
Continuity Equation
Using Velocity time integral (VTI)
AVA= .785 x (LVOT)2 x LVOT (VTI) /
AV (VTI)
AVA= .785 x (2.0 cm)2 x 11.0 cm / 59cm
AVA= .6cm2
AVA Calculation
Simplified Continuity Equation
Using peak (max) velocity
AVA= .785 x (LVOT)2 x (V) LVOT / (V)AV
AVA= .785 x (2.0 cm)2 x 56.0 cm/s / 288 cm/s
AVA= .6cm2
AS Severity Scale
Normal
Mild
Moderate Severe
Mean
0
Gradient(mm Hg)
<25
25-40
>40
Peak Gradient
(mm Hg)
<35
35-60
>60
1.6-3.0
1.0-1.5
<1.0
0
Valve Area (cm2) 3.0-4.0
Feigenbaum’s Echocadiography , Seventh edition , William Armstrrong and Tom Ryan,
2010
Dimensionless Index
•
•
•
•
Useful when LVOT cannot be
measured
Velocity ratio = V (LVOT) / V (AS)
Severe = .25 or less
Corresponds to a valve area of 25%
of normal
AVA Planimetry
Insert your slide text in
this area.
•Bullet
•Bullet
•Bullet
Planimetry by 2D echo
•
•
•
•
•
TTE, TEE, 3D echo
Anatomic (geometric) cross sectional
area measured freehand from 2D or
3D echo
Difficult to perform accurately
Useful if Doppler not available
TEE best
Mitral Stenosis
•
•
•
•
•
•
•
Valve anatomy
Commissural fusion- Psax
Leaflet thickening, calcification- Plax
Valve mobility- Plax
Annular calcification
Rheumatic vs degenerative
Congenital- subvalvular apparatus
Mitral Stenosis
•
•
•
•
•
Doppler diastolic pressure gradient
Bernoulli equation, change pressure
=4V2
Apical window parallel alignment of
beam to MV flow, continuous wave
Mean pressure gradient derived from
MV trace
Atrial fibrillation requires average ~ 5
MV Pressure Gradient
Mean pressure gradient 6-12 moderate, >12 mmHg severe
Mitral Stenosis
•
•
•
•
•
MV area, planimetry
Direct measure of MV area
Psax, measure at leaflet tips
Scan from base to apex to find
largest area
Mid-diastole, cineloop through frozen
image
MVA by Planimetry
Mitral Stenosis
•
•
•
•
•
Doppler - Pressure Half time
Deceleration slope of MV inflow
MVA = 220 / pressure half time
Atrial fibrillation average of 5
Avoid short diastole during selection
Mitral Stenosis
•
•
Pressure half time (PHT) (t ВЅ)
MVA= 220 / t ВЅ
DT= time from peak velocity to zero
baseline
PHT proportionally related to DT
PHT is always 29% of the DT
T1/2 =DT x 0.29
Mitral Valve Severity
• Cut off point for MVA <1.5 cm with
symptoms
Pulmonary Artery Systolic
Pressure
• Continuous Wave
Doppler jet velocity
пЃ„P=4x(4.6)2
пЃ„P=85 mmHg
RVSP=85
RVSP=85 mmHg+RAP
(RAP
(RAP is estimated)
Right Atrial Pressure Estimation
Brief
sniff
IVC SIZE
Diameter decrease
Estimated RAP
< 1.7cm
> 50%
0-5 mmHg
> 1.7cm
> 50%
6-10 mmHg
>1.7 cm
< 50%
10-15 mmHg
>1.7 cm
No change, 0%
> 15 mmHg
Tricuspid Valve Stenosis
•
•
•
•
•
Similar to mitral valve stenosis
methods
Respiratory variation on Doppler
especially with inspiration
Anatomical assessment of valve
Thickness, calcification
Mobility, diastolic doming, reduced
leaflet mobility
Tricuspid Valve Stenosis
•
•
•
•
•
•
Mean pressure gradient, > 5 mm Hg
Inflow TV (TVI), > 60 cm
Valve area by continuity equation<
1cm2
Right atrial enlargement > moderate
Dilated IVC
Combination lesion- TS/TR
Pulmonic Stenosis
•
•
•
•
•
•
Transpulmonary pressure gradient
Simplified Bernoulli Equation
P= 4V2
CW- Parallel to flow
Infundibular and subvalvular
stenosis may require analysis of full
Bernoulli equation
PW can help identify jet location
Pulmonic Stenosis
Pulmonic Valve Stenosis
Peak Velocity (m/s)
•
Mild
Moderate
Severe
<3
3-4
>4
36-64
>64
Enter Objectives
here
<36
Peak Gradient
•RVOT
•RVH
•RV function/ size
Mitral Regurgitation
• Determining severity requires multiple
methods
• Jet Area / Pattern / Characteristics
• CW signal strength
• Vena Contracta Width
• PISA
• Pulmonary vein flow
• Regurgitant volume / Regurgitant fraction
Regurgitation - Jet Area
Factors affecting Jet Area
• LA pressure/ size
• Systemic BP
• Jet Direction (eccentricity)
• Nyquist limit 50-60 cm
• % of jet area/LA area
• Mild - severe
• <20%, >40%
Regurgitation- Vena Contracta
• Parasternal long axis
• Zoom view
• Measure narrowest portion of jet as it
emerges from the orifice
• Useful with central and eccentric jets
• Not useful with multiple jets
Vena Contracta
Stroke Volume (SV)
• CSA LVOT diameter x LVOT VTI = Ao SV
• Mitral annulus diameter x MV VTI = MV SV
LVOT Diameter
x
LVOT VTI
= SV
.785 x (LVOT D)2= CSA
Pulsed wave
Regurgitant Volume (RV)
• Calculating Regurgitant Volume
• RV MV = SV (MV) – SV (AV)
• Calculate Regurgitant Fraction
• RF= RV / SV
• RF (MV) = RV (MV) / SV (MV)
Effective Regurgitant Orifice
Area (EROA)
• CW Doppler of regurgitation jet (optimal)
• Trace jet for VTI
• EROA = RV (MV) / VTI (MR)
Proximal Isovelocity Surface Area
(PISA Method)
• Zoomed images of the mitral valve
• Color flow Doppler – adjust the regurgitant aliasing velocity
(baseline shift towards flow direction) down to 30-40 cm/sec
range to better define the aliasing velocity
– Lowering the Nyquist limit will also achieve a well defined PISA
hemisphere (lowers wall filter)
• Measure PISA radius in peak systole
• Note aliasing velocity (Va)
• Obtain CW Doppler with cursor parallel in the center of flow.
Trace MR envelope for VTI and also mark peak velocity (V)
• EROA (cm2) = Flow (cc/sec) / V (cm/sec)
• flow= 6.28 x (r 2) x (aliasing velocity)
Image Modified from Echo in Context
PISA for Evaluation of Mitral
Regurgitation
PISA is Proximal Isovelocity Surface Area - It is located at the flow convergence of
the regugitant valve
• Magnify (zoomed) mode
• Shift color Doppler baseline
• Obtain a PISA with a Nyquist limit at approximately 30- 40 cm/sec
PISA for Evaluation of Mitral
Regurgitation
Apical
4 chamber
Capture PISA from the
BEST apical view
Apical
2 chamber
Apical
long axis
PISA for Evaluation of Mitral
Regurgitation
Place the CW Doppler
cursor parallel in
the center of mitral
regurgitation
Tricuspid Regurgitation
Align Doppler
parallel to flow
Aortic Regurgitation
1.
2.
3.
4.
Anatomy of the Aortic valve
Mechanism of the leak
Left ventricular function
PISA
Count leaflets
3
2
1
Pressure Half Time
Aortic Regurgitation
Suprasternal notch, aortic diastolic flow reversal
Pulmonic Insufficiency
Thank you!
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