Echocardiographic assessment of
Mitral regurgitation
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Detection
Assessment of severity
Etiology
Management strategy
• Detection-color doppler
• Appearance of color doppler in LA in systole
– postr motion of blood pool by MV closure
– Reverberation from aortic flow
– Normal pulmonary vein inflow
• Characteristics of true MR
– Proximal flow acceleration
– Ejection flow with a vena contracta
– Downstream appearance-blood ejected through a
constraining orifice
– Confined to systole
– Doppler signals appropriate in color
• Jet of MR
– Central or peripheral
– Single or multiple
• Eccentric jet
– Flail or partial flail of a leaflet-flow direction
opposite to involved leaflet
– Ischemia-restriction of motion of one leaflet
Determination of severity
• CW doppler signal intensity
• intensity of doppler signal proportional to number of
blood cells moving
• weak signal-mild regurgitation
– Limitations
• Affected by anatomic,physiological and technical
factors
• Comparison with CWSI of antegrade flow
• Shape of regurgitant signal-V cut off sign
• Mild MR-atrial pressure low and gradient remain high
throughout systole
• Significant MR-atrial pressure increased in end systole
and gradient decreases
• Produces a V shaped doppler signal
• Flow pattern in pulmonary vein
• AP-4C view-PW placed in right upper pulmonary vein
• Normal-systolic flow predominates
• Moderate MR-loss of systolic flow with brief systolic
reversal
• Severe MR –holosystolic flow reversal
• Pulmonary venous doppler-systolic VTI to
diastolic VTI ratio to assess severity of MR
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>1-mild
0.5 to 1-moderate
0 to 0.5-moderately severe
<0-severe
• Limitations
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AF-blunting of systolic component
Not detected if wall filters set too high
Absent in a dilated and compliant LA
False positive in eccentric jet directed to a vein
• Regurgitant jet area to left atrial area ratio
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<15-mild
15-30-moderate
35-50-moerately severe
>50-severe
• Limitations
• Doppler encoded size of jet overstates true volume of
flow from LV by amount of pre existing LA blood
recruited into motion
• Eccentric jet-smaller amount of recruitment and
underestimation of severity
• Low gain setting-underestimate severity
• High gain-cluttering of image with noise and
difficult to identify true outline of regurgitant
jet
• Non parallel alignment-lower frequency shifts
• Vena contracta
• Narrowest portion of MR jet downstream from the
orifice
• Vena contracta width correlates with severity-<3mm
mild,>6mm severe
• Remains accurate in acute regurgitation when jet area
may be misleading
• Recommended approach
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perpendicular to jet direction
Narrow sector width
Zoom mode
Minimum depth
Calculation of regurgitant volumes
and regurgitant fractions
• Stroke volume through all valves should be
equal in absence of shunts or reg.
• Stroke volume through a reg.valve will be
stroke volume plus reg.volume
• R vol= SV (MV) --- SV (LVOT)
• RF=Reg.V/SV(MV)x100
• SV through LVOT
• Annulus diameter
• PLAX view
• Level of aortic annulus in systole
• Inner edge to inner edge
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CSA=0.785xD²
VTI of LVOT from AP5C
LVOT SV=CSAxVTI
SV through MV –AP4C for annulus diameter
and VTI
• Reg.volume=SV(mv)-SV (lvot)
• Reg .fraction=RV÷SV(lvot)
• Stroke volume of LV can also be calculated
from 2-D echo by simpson biplane method
• ERO=RV/VTI(MR jet)
• Limitations
– Equations based on steady flow through
cylindrical tube
– Errors in diameter measurement-same phase as
VTI
– Errors in VTI –Poor alignment,incorrect
placement,improper tracing
– Intracardiac shunts
– Presence of multivalvular lesions
• PISA method for calculation of ERO area
• Acceleration of flow occurs proximal to regurgitant
orifice
• A series of isovelocity surfaces leading to high velocity
jet in the orifice
• Continuity principle-blood flow through a given
hemisphere must ultimately pass through the narrowed
orifice
• AP4C view
• Optimise color flow signal of regurgitant
orifice
• Decrease aliasing velocity by shifting color
baseline
• Aliasing limit noted
• Radius measured from aliased region to MV
• Reg.flow calculated
• Max.MR velocity calculated
• ERO=MR flow/velocity of MR jet
Eccentric jet
• MVP– Defined as systolic displacement of >2mm of one
or both mitral leaflets into the LA below the plane
of mitral annulus
– Mitral leaflets often thickened >5mm or
myxomatous
– MVP with thickening of leaflets prone for
complications
– Prolapse with otherwise normal leaflets and no
MR –low risk
MVP
• Rheumatic MR-commissural fusion,chordal
fusion and shortening
• Infective endocarditis-leaflet
destruction,perforation or deformity
• Marfan syn.-long redundant antr.leaflet,aortic
pathology
• Ischemic MR-restricted leaflet motion
• Papillary muscle rupture-a/c MI
• Functional MR-annular dilatation
• Mitral annular calcification-impair systolic
contraction leading to MR
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LV dilatation
LA dilatation
Decline in LV contractility
PA pressure from TR jet
Thank you