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Specimen picture showing the base of the heart with the location of two- and four-chamber echocardiographic views superimposed (double-headed arrows). (1) Base of the adult heart specimen showing the mitral valve with double-headed arrows superimposed demonstrating the two- and four-chamber echocardiographic approach. Δ, anterolateral commissure; ▴, posteromedial commissure; A1–A3, divisions of the aortic mitral leaflet; P1–P3, divisions of the mural leaflet of the mitral valve; LAA, left atrial appendage; PT, pulmonary trunk; NC, non-coronary cusp of the aorta; LCC, left coronary cusp of the aorta; RCC, right coronary cusp of the aorta.
Three-dimensional transesophageal images, surgical view (live 3D zoom mode). This shows ischaemic mitral regurgitation. The patient suffered an inferoposterior infarction with resultant tethering of the posteromedial papillary muscle. The image depicts the failure of coaptation (dotted region) of leaflets in the P2 and P3 regions. These segments are resticted to closure in systole.
ECHOCARDIOGRAPHIC EVALUATION OF MITRAL VALVE DISEASE -MITRAL REGURGITATION
Brief review of Mitral apparatus,MR
Etiology of MR
Differentiation of Primary and Secondary MR
Acute and Chronic MR
Grading the severity of MR
Mitral Regurgitation (MR) represents a pathologic leak of
blood under systolic pressure from LV to LA.
MR occurs during systole, which constitutes 1/3 of cardiac
cycle at normal resting Heart rate.
Can be due to primary disease of mitral leaflets.
Secondary to abnormality of mitral apparatus.
Acute MR – Acute pulmonary congestion.
Chronic MR – compensated, well tolerated for decades.
Mitral valve apparatus
Normal mitral apparatus is a saddle shaped ellipse with its
most apical points seen in the apical four chamber view and
its most basal points seen in the long axis view.
Mitral annulus is smaller in systole than in diastole.
Normal area of overlap or apposition, some degree of mitral
annular dilation may be tolerated without significant
Normal Dilated cardiomyopathy
Non planar mitral annulus shape present reduced,flattened
Area,cm2 7-12 11-20
circumference 7-11 8-18
% area change diastole/systole 20-42 13-23
Posterior part is easily dilated compared to Anterior part of
annulus. All current operative mitral valve repair techniques
are based on this principle of asymmetric annular dilatation.
Mitral valve annuloplasty reduces the mitral valve inlet area
by reducing the circumference of the posterior leaflet. This is
the rationale for using a partial posterior annuloplasty ring.
Anterior mitral leaflet area to MA area ratio of 1.5-2.0 has
been found sufficient to prevent mitral regurgitation.*
*Chaput et al,
Mitral leaflet adaptation to ventricular remodelling occurrence
and adequacy in patients with functional MR,Circulation 2008;118:845-52
Described by Dr. Alain Carpentier.
Understanding of mitral valve pathology.
Long term prognosis depends upon etiology, treatment strategy
depends on dysfunction, surgical management depends upon lesion.
Carpentier A, Adams DH, Filsoufi F. Carpentier’s Reconstructive Valve Surgery.
From Valve Analysis to Valve Reconstruction. 2010 Saunders Elsevier.
Describes the mechanism of Mitral valve dysfunction.
Opening and closing of the mitral leaflets.
Carpentier A. Cardiac valve surgery – “the French correction”
J Thorac Cardiovasc Surg 1983;86:323-37
At the leaflets
Excessive motion of the leaflets.
Prolapse of leaflets
Sequelae of a myxomatous mitral valve.
Degree of resultant regurgitation is directly related to the extent
of anatomic disruption.
Rupture of only a few isolated chordae – may not result in loss
of normal coaptation –absence of MR.
Eccentric direction of MR – orientation opposite in direction of
the leaflet with anatomic defect.
A1:P1 – anterolaterally – LA appendage.
A3:P3 – inferomedial location, close to tricuspid
The scallops A1 and P1 are when viewed Left from LA view by
the surgeon; whereas right and inferior on TEE.
TEE - 120 longitudinal plane – imaging plane intersects A2/P2
Confusion – orthogonal to the above view -60 .P1,A2,A3
visualized.(confusion between a flail P3 and A3 scallop in this
In general, Posterior flail is easier to repair than an anterior flail.
feigenbaum echoFig 12.57 a video.flv
feigenbaum echoFig 12.57 b video.flv
feigenbaum echoFig 12.58 a video.flv
feigenbaum echoFig 12.58 b video.flv
feigenbaum echoFig 12.59 a video.flv
feigenbaum echoFig 12.59 b video.flv
FLAIL MITRAL LEAFLET -
ECHOCARDIOGRAPHY SERIES BY
In more than 70% cases,it affects the posterior
leaflet and leads to severe MR.
Large vegetations can preclude leaflets coaptation and can
lead to severe MR.
vegetation on both leaflets of the mitral
Myxomatous Mitral Valve
Thickened redundant leaflets and chordae with excessive motion
and sagging of portions of the leaflets into the LA in systole.
Severity of disease ranges from mitral valve prolapse (minimal
displacement of the leaflets into the LA in systole),to severely
involvement of both leaflets by myxomatous disease with frankly
prolapsed or flail leaflet segments.
Billowing mitral valve
When a part of the mitral valve body protrudes into the left
atrium. However,the coaptation line is preserved beyond
the annular plane.
MR is usually mild in this condition.
Morphological abnormality with thickened leaflet (diastolic
thickness >5 mm) due to redundant tissue.
Video of MVP
feigenbaum echoFig 12.84 a video.flv
feigenbaum echoFig 12.84 b video.flv
Long redundant anterior leaflet that sags into the LA in
Chordal shortening and fusion are more prominent.
Fibrosis of the chordae attached to the posterior valve is more
frequent and explains the rigidity and reduced motion of the
posterior leaflet in diastole.
Semi open position of the PML through out cardiac cycle,the
motion of anterior leaflet in systole produces a false aspect of
Chordal disruption or elongation
Inadequate tensile support of the closed leaflets in systole.
Severe bowing of the leaflet or the leaflet segment, into the
LA, with the tip of the leaflet still directed towards the
Chordal rupture – flail segment of the leaflet such that the
leaflet is displaced into the LA in systole, tip of leaflet pointing
away from left ventricular apex.
3DTEE imaging is imp. in evaluation.
Delineation of the precise segments of anterior and posterior
leaflets involved will help in approach surgically.
Papillary Muscle Rupture
Acute severe MR.
Normal sized left atria.
Opposite to the direction of the
papillary muscle the jet
Normal contraction of the mitral annulus(decrease in
annular area in systole) is 25%.
Increased echogenicity with acoustic shadowing on the left
ventricular side of the posterior annulus in the elderly or in
patients with renal failure is a typical finding.
Mitral Annular Calcification
Seen in elderly, younger patients with hypertension, renal failure.
Increased rigidity of the annulus.
Impairs systolic contraction of the annulus.
Area of increased echogenicity on the LV side of the annulus
immediately adjacent to the attachment point of the posterior
Acoustic shadowing due to calcium.
Short axis view – annular calcium can be focal or extensive,
involving the entire U shaped posterior annulus.
Region of anterior mitral leaflet – posterior aortic wall
continuity is involved only rarely.
Regional LV dysfunction with abnormal contraction of the
papillary muscle or underlying ventricular wall.
In patients with MI, myocardial scarring results in MR at rest.
MR may be intermittent in patients with inducible ischemia.
Restricted leaflet motion.
Tethering of valve closure resulting in appearance of tenting or
tethering of mitral valve in systole.
TTE is useful – for evaluation of LV,RV,PAP, mechanism of MR.
Valve disruption or perforation from IE, chordal rupture ,papillary
TEE when TTE is inconclusive
Valvular vegetations,annular abscesses.
TEE to be performed as soon as possible in presence of acute and
hemodynamic instability after MI with hyperdynamic LV function
by TTE and no other cause for deterioration, looking for severe
MR due either to a papillary muscle or chordal rupture.
Nishimura et al,ACC/AHA 2014 VHD Guidelines.
Left atrial dilation
Left ventricular volume and stroke volume
Flail or perforated leaflet
Jet area indexed to left atrium
Central vs eccentric jets
Vena contracta width
Proximal isovelocity surface area
Volumetric flow/regurgitant volume
Effective regurgitant orifice
Pulmonary vein flow reversal
Forward flow calculation at the mitral annulus
Elevated E/A ratio (with normal left ventricular function)
Color doppler imaging is the primary echocardiographic tool
for detection and quantification of MR.
Spectral doppler – for confirmation, define duration of MR.
“ Not all color doppler signals appearing
within LA represent mitral regurgitation”.
Several potential sources of color
doppler flow signal in LA
Normal posterior motion of blood pool caused by mitral valve
Reverberation from aortic flow.
Normal pulmonary vein flow.
Atrial blood pool motion of overall low velocity
inappropriately visualised because of inappropriate gain and
MR when suspected to be confirmed in multiple views.
feigenbaum echoFig 12.43
Normal posterior motion of blood pool
caused by mitral valve closure Reverberation from aortic flow
Characteristics of True MR jet
Evidence of proximal flow acceleration.
Flow conforms to appearance of true jet
The down stream appearance is consistent with a volume of blood
being ejected through a relatively constraining orifice(vena
Flow signal appropriately confined to systole.
Color doppler signal are appropriate in color for the anticipated
direction and/or reveal appropriate variance or turbulence
Differentiation of Primary MR from
2D echo is recommended as first imaging modality.
PSax view permits the assessment of the six scallops and with
color doppler imaging, the localisation of the origin of the
regurgitant jet may identify prolapsing segments.
PLax view classically shows A2 and P2.
Angulation of probe towards aortic valve allows the
visualisation of A1 and P1.
Towards the tricuspid , the visualisation of A3 and P3.
Apical four chamber view –A3,A2,P1 (internal to external)
Two chamber view – P3,A2,A1( left to right).
3D imaging is superior to describe mitral pathology, especially
for anterior leaflet defects in degenerative disease and
commissural fusion in rheumatic process.
Enface view is identical to the surgical view in the operating
Secondary Mitral Regurgitation
Incomplete leaflet coaptation.
Either due to LA dilation or LV dilation.
The diameter of the mitral annulus is compared with the
anterior leaflet measured in diastole.
Annular dilation is present when the annulus/ anterior
leaflet ratio is more than 1.3 or when the diameter of the
mitral annulus is more than 35 mm.
Annulus becomes more circular (saddle shape usually).
Caldarera et al,Multiplane TEE and morphology of regurgitant mitral valves in surgical repair.
Eur Heart J. 1995;16(7):999-1006
LV remodelling and mitral valve
Unbalance between the increased tethering forces and the decreased
Reduced closing forces –
altered systolic annular contraction
reduced LV contractility.
global LV dyssynchrony at the level of basal segments
Reduced synchrony between the papillary muscles.
Asymmetric pattern 95% cases – systolic restriction of the PML
Seagull sign – traction on the anterior leaflet by secondary chordae.
Symmetric pattern - NICMP,MVD
Traction on the AML by the secondary chordae.
Altered geometry of the mitral valve apparatus is quantified by
the tenting area and the coaptation distance.
The tenting area is measured in mid systole as the area
enclosed between the mitral annulus plane and the mitral
Coaptation distance represents the apical displacement of the
coaptation point and is measured as the distance between the
mitral annular plane and the point of leaflet coaptation in the
apical four chamber view.
Distance between the posterior papillary muscle head and the
Lateral and posterior displacement of the papillary muscles.
Acute vs chronic MR
Acute MR Chronic MR
Etiology Leaflet perforation
Papillary muscle rupture
LA pressure Significantly elevated normal
LA size normal Dilated (compliant)
Doppler signal High initial velocity with a
rapid fall in late systole
High velocity through out
Pulmonary pressure high normal
LV dimensions normal increased
DOPPLER evaluation…an integrative approach
How to grade Mitral Regurgitation
Ruptured papillary muscles
Large coaptation defect .
Acute elevation of left atrial pressure can lead to
underestimation of MR severity with color flow imaging.
Color flow imaging
Regurgitant jet is frequently measured by planimetry.
The size and the extent of the jet into the LA increase with the
Regurgitant jet more than 40% of the LA area – SevereMR.
Source of technical errors.
Large eccentric jet ahering,swirling and reaching the posterior
wall of the left atrium is in favor of significant MR.
Small jets appearing just beyond the mitral leaflets usuallt
indicate mild MR.
Color flow area
Identifying central MR jets
Evaluation of spatial orientation of the jet.
Not recommended for use in the grading of MR severity of eccentric
jets, significantly underestimates the regurgitant volume (upto 40%)
when compared with central jets with the same volume.
Yoshida et al,
Color doppler evaluation of valvular regurgitation,Circulation 1988:78(4):840-7
< 4cm² or <20 cm² of LA size mild MR
4 - 10 cm² or 20 – 40cm²of LA size moderate MR
>10 cm²or 40 cm² of LA size severe MR
Influenced by hemodynamic and technical factors:
Low blood pressure, acute MR – underestimate.
Eccentric jet - underestimate.
Color gain and nyquist scale optimization.
There is now a general consensus as reflected in the recent
guidelines by both the American Society of Echocardiography and
the European Assosciation of Echocardiography, that color flow jet
assessment should only be used for diagnosing MR and not for MR
Precise quantification is by using vena contracta width and the flow
Qualitative approach to evaluate MR severity.
Useful adjunct to other quantitative measurements.
Adequate alignment of the beam with MR jet profile is crucial for
an accurate representation of MR severity.
Difficult to obtain in eccentric jet.
Soft density, incomplete envelope mild
Dense signal with triangular shape severe
Continuous wave doppler
Qualitative guide to MR severity.
Dense MR signal with a full envelope indicates more severe
MR than a faint signal.
CW envelope may be truncated (notch) with a triangular
contour and an early peak velocity. – elevated pressure and a
prominent regurgitant pressure wave in the left atrium due to
Difficult in case of eccentric MR.
Vena contracta width
Easy and quick method
Relatively independent of hemodynamic factors.
Limited by its narrow range.
Image optimization needed
Zoom mode with narrow sector and plane perpendicular to the jet
is essential to improve spatial and temporal resolution.
2 chamber view (commissural view) is parallel to the mitral
leaflet coaptation line, even mild degrees of functional
regurgitation can appear to show a wide VC(not recommended)
< 0.3 cm mild MR
0.3 – 0.7 cm moderate MR
> 0.7 cm severe MR
•Can be used in eccentric jet.
•Accurate in acute MR.
•Not valid for multiple MR Jets.
The accuracy of vena contracta is based on the assumption
that the regurgitant orifice is circular,which is often the case in
organic MR. However,regurgitant orifice in functional MR is
rather elongated and non circular,limiting the validity of vena
To note,the respective values of vena contracta width are not
additive for multiple jets.
Adds additional information to MR severity.
Complement to other methods.
Normal flow pattern is assosciated with mild to moderate MR
Reversal of a systolic wave is highly reliable marker of severe or
moderate to severe regurgitation.
Blunted systolic waves – less predictive value.
Non significant MR jet can be selectively directed at a pulmonary
vein, causing reversal of flow in that particular vein, potential
overestimation of MR severity.
Assess the flow pattern in 2 or more different pulmonary veins before
concluding a positive finding of blunting or reversal systolic flow
compatible with significant MR.
Systolic dominance mild MR
Systolic flow reversal severe MR
Influenced by LA pressure and LV relaxation
Not accurate in atrial fibrillation
Mitral inflow pattern
Qualitative and complementary approach to MR severity.
Mitral to aortic time velocity integral (TVI) ratio of the pulsed
wave doppler profile of mitral and aortic valves could be used to
quantify isolated organic MR.
A ratio greater than 1.4 suggests severe MR.
< 1.0 mild MR.
A wave dominant excludes severe MR.
E wave >1.5 cm/sec – severe MR
Influenced by LA Pressure and LV relaxation.
Not accurate in Atrial Fibrillation
Effective Regurgitant Orifice Area (EROA)
Useful to define the intermediate degrees of MR.
European recommendations for MR quantification have taken
into account the different characteristics of primary and
40 mm² Primary MR
20 mm² Secondary MR
Guidelines on the management of valvular heart disease 2012 ,
ESC,Eur J Cardiothoracic Surg 2012;42(4):S1-44
2D Proximal Isovelocity Surface Area
Current recommended quantitative approach.
Qualitatively, presence of flow convergence at a Nyquist limit of
approximately 50 -60 cm/sec(routine examination) would suggest
PISA calculations are based on following parameters.
EROA = 2r² Va/Peak MRV(CW)
EROA = effective regurgitant orifice area
Va = alaising velocity
RV (cc) = EROA TVI MR (cm)
RV = regurgitant volume
TVI = MV time –velocity integral
PISA method assumes that the ROA is constant through out
systole and is hemispheric in shape.
PISA based methods tends to be more accurate for organic than
for functional MR.
PISA radius is constant in patients with organic rheumatic MR,
increases progressively along the systole period in patients with
mitral valve prolapse.
In functional MR, an early peak is followed by a progressive
midsystolic decrease, sometimes with another late systolic
MR volume = Mitral inflow – aortic outflow
Mitral inflow volume = TVI CSA (mitral annulus)
Aortic outflow = TVI CSA(LVOT)
TVI at the level of mitral annular plane, as this is where the cross-
sectional area is measured.
Cross sectional area of mitral annulus is assumed to be circular and
calculated as r²,where r is the diameter measured in the apical
chamber view divided by 2.
Anatomically mitral annulus is D shaped,more like an ellipse rather
than a circle.
Circular assumption is reasonable for who have developed atleast
moderate MR(annular dilation)
Ellipse - ab - diameters measured in A2C,A4C views.
This method assumes there is no aortic regurgitation.
In that case, pulmonary outflow can be used, assuming no pulmonary
Potential errors that may arise from the multiple
measurements required at different views to calculate RV,
Significant training required.
Small errors in measurement are amplified and accurate
resolution of the annulus is important in minimizing
Mitral Regurgitation severity
I (MILD) II III IV(SEVERE)
LV size Normal normal Increased
Left atrial size normal normal
MR Jet (% LA) <15 15-30 35-50 >50
faint - - dense
Vena contracta < 3 mm - - >6 mm
S >D - - Systolic reversal
RV (ml) < 30 30-44 45-59 >60
ERO (cm²) < 0.2 0.2-0.29 0.3-0.39 >0.4
PISA small - - large
LVEF < 55%
DT-E <150 msec
E/E’ (lateral ) >15
Vp < 45 cm/sec
PASP > 35 mHg
LA size >55 mm
LVDD >70 mm
Better definition of mitral morphology
Improves the characterization of mitral regurgitant jets.
Spatially visualize the shape, size,orientation of MR jets in
real time,thus enhancing the accuracy of quantification of MR
3D VC area
Eccentric or functional regurgitations.
3D guided planimetry of VCA – relatively fast, highly feasible,
very precise indicator of MR severity in clinical practice.
VC width vary depending on the image plane.
Commissural views can be inaccurate.
When True short axis imaging in 2D echo, for the real shape of
VC to be visualized is challenging.
Most reproducible and accurate method to establish the ERO.
VCA to be slightly smaller than the real anatomic orifice.
Can be used in multiple jets.
VCA should be measured at aliased velocities to avoid the
possibility of color bleeding that may occur at lower non
True proximal flow convergence region is rather more
hemielliptical than hemispheric
Yosety and colleagues – calculation of EROA by 3D can
greatly improve the accuracy of 2D based PISA assessment.
Underestimation can be significantly corrected.
Low temporal resolution.
“Volume” or “voxel” rates in real time is low even with small
angles of view.
Color doppler gain(effect on size,no effect on area)
Instantaneous ROA should be integrated throughout
Ischemic Mitral Regurgitation
Frequent complication of MI,CAD
Developed in setting of coronary disease.
Mitral leaflets are intrinsically normal.
Initiating insult is ventricular remodelling.
Acute MR – ruptured papillary muscle following MI.(<1%)
Papillary muscle ischemia – uncommon.(MR resolves once
Chronic MR –secondary to ventricular remodelling due to
feigenbaum echoFig 12.68 a video.flv
feigenbaum echoFig 12.68 b video.flv
feigenbaum echoFig 12.69 a video.flv
feigenbaum echoFig 12.69 b video.flv
feigenbaum echoFig 12.70 a video.flv
feigenbaum echoFig 12.70 b video.flv
Mitral leaflets coapt apically within the LV – restricting
leaflet closure in a pattern known as incomplete mitral leaflet
Mitral valve function depends upon the ventricular support
structures, should not be seen as free standing leaflets attached
at the annulus.
Papillary muscles and chordae tendinae serve to anchor the
leaflets at the annular level during coaptation.
Predominant role of tethering as the final common pathway in
inducing functional MR.
Posterolateral displacement of the papillary muscles.
Stretching of the chordae tendinae
Increased tethering forces on the mitral valve leaflets.
Apical leaflet coaptation
Restricted leaflet closure
Annular dilation can also result in MR
feigenbaum echoFig 12.68 a video.flv
feigenbaum echoFig 12.68 b video.flv
feigenbaum echoFig 12.69 a video.flv
feigenbaum echoFig 12.69 b video.flv
feigenbaum echoFig 12.70 a video.flv
feigenbaum echoFig 12.70 b video.flv
Cleft mitral valve
feigenbaum echoFig 12.55 a video.flv
feigenbaum echoFig 12.55 b video.flv
Consequences of MR
Pulmonary artery pressure
In the chronic compensated phase (the patient could be
asymptomatic), the forward stroke volume is maintained
through an increase in LV ejection fraction typically
In the chronic decompensated phase (the patient could
still be asymptomatic or may fail to recognize
deterioration in clinical status), the forward stroke volume
decreases and the LA pressure increases significantly.
The LV contractility can thus decrease silently and
irreversibly. However, the LV ejection fraction may still
be in the low normal range despite the presence of
significant muscle dysfunction.
In the current guidelines, surgery is recommended in
asymptomatic patients with severe organic MR when the
LV ejection fraction is ≤60%.
The ESD (end-systolic diameter) is less preload
dependent than the ejection fraction and could in some
cases be more appropriate to monitor global LV function.
An end-systolic diameter >45 mm (or ≥40 mm or >22
mm/m2, AHA/ACC) also indicates the need for mitral
valve surgery in these patients.
A systolic tissue Doppler velocity measured at the
lateral annulus < 10.5 cm/s has been shown to
identify subclinical LV dysfunction and to predict
post-operative LV dysfunction in patients with
asymptomatic organic MR.
Strain imaging allows a more accurate estimation
of myocardial contractility than tissue Doppler
It is not influenced by translation or pathologic tethering to
adjacent myocardial segments, which affect myocardial
In MR, strain has been shown to decrease even before LV ESD
exceeds 45 mm.
A resting longitudinal strain rate value <1.07/s (average of
12 basal and mid segments) is associated with the absence of
contractile reserve during exercise and thus with subclinical
latent LV dysfunction.
By using the 2D-speckle tracking imaging (an angle
independent method), a global longitudinal strain <18.1%
has been associated with postoperative LV dysfunction.
Practically, the incremental value of tissue Doppler and strain
imaging for identifying latent LV dysfunction remains to be
LA size and Pulmonary pressures
The LA dilates in response to chronic volume and pressure
A normal sized LA is not normally associated with significantMR
unless it is acute, in which case the valve appearance is likely to be
LA remodelling (diameter >40–50 mm or LA volume index >40
mL/m2) may predict onset of AF and poor prognosis in patients
with organic MR.
Conversely, MV repair leads to LA reverse remodelling, the extent
of which is related to preoperative LA size and to procedural
The excess regurgitant blood entering in the LA may induce
acutely or chronically a progressive rise in pulmonary pressure.
The presence of TR even if it is mild, permits the estimation of
systolic pulmonary arterial pressure.
Recommendation for mitral valve repair is a class IIa when
pulmonary arterial systolic pressure is >50 mm Hg at rest.
Risk of SAM after surgery
Myxomatous mitral valve with redundant leaflets (excessive
anterior leaflet tissue)
A non dilated hyperdynamic LV
Short distance between the mitral valve coaptation point and
the ventricular septum after repair.
Echocardiography is an important diagnostic tool in the
evaluation of mitral regurgitation and helps to
differentiate acute from chronic,organic from
functional,the consequtive effect of MR ,feasibility of
repair in the patients and as an effective guide during
the interventions,and also during follow up.