echocardiographic evaluation of mitral valve disease -mitral regurgitation

ECHOCARDIOGRAPHIC

EVALUATION OF

MITRAL REGURGITATION

Dr.PRAVEEN NAGULA

Contents

Introduction

Brief review of Mitral apparatus,MR

Etiology of MR

Evaluation

Differentiation of Primary and Secondary MR

Acute and Chronic MR

Grading the severity of MR

Conclusion

Introduction

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.

Brief Review of MR

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

regurgitation.

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

Pathophysiological triad

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.

Functional classification

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

Etiology

of

MITRAL REGURGITATION

Mitral

Regurgitation

Primary (organic)

Rheumatic

Endocarditis

Fibroelasticdeficiency

Flail

Prolapse

Myxomatous

degeneration

Flail

Prolapse

Secondary (functional)

Annular dilation

Dilated cardio

myopathy

Papillary muscle rupture

Acute MI

At the leaflets

Excessive motion of the leaflets.

Leaflet perforation.

Prolapse of leaflets

Flail leaflet

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

annulus.

Echo views

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

boundary.

Confusion – orthogonal to the above view -60 .P1,A2,A3

visualized.(confusion between a flail P3 and A3 scallop in this

view).

In general, Posterior flail is easier to repair than an anterior flail.

Specimen picture showing the base of the heart with the location of two- and four-

chamber echocardiographic views superimposed (double-headed arrows).

McCarthy K P et al. Eur J Echocardiogr 2010;11:i3-i9

Published on behalf of the European Society of Cardiology. All rights reserved. © The Author

2010. For permissions please email: [email protected]

Three-dimensional transesophageal images, surgical view (live 3D zoom mode).

McCarthy K P et al. Eur J Echocardiogr 2010;11:i3-i9

Published on behalf of the European Society of Cardiology. All rights reserved. © The Author

2010. For permissions please email: [email protected]

“Tiger stripes”

video

feigenbaum echo\Fig 12.57 a video.flv

feigenbaum echo\Fig 12.57 b video.flv





FLAIL MITRAL LEAFLET -ECHOCARDIOGRAPHY SERIES BY DR.ANKUR.K.CHAUDHARI_(360p).mp4

feigenbaum echo/Fig 12.57 a video.flv

feigenbaum echo/Fig 12.57 b video.flv





FLAIL MITRAL LEAFLET - ECHOCARDIOGRAPHY SERIES BY DR.ANKUR.K.CHAUDHARI_(360p).mp4

In more than 70% cases,it affects the posterior

leaflet and leads to severe MR.

Infective Endocarditis

Type I

Leaflet destruction

Perforation

Deformity

Large vegetations can preclude leaflets coaptation and can

lead to severe MR.

C:\Users\LAPTOP\Documents\endocarditis_large

vegetation on both leaflets of the mitral

valve_(360p).mp4

C:/Users/LAPTOP/Documents/endocarditis_large vegetation on both leaflets of the mitral valve_(360p).mp4

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.

Floppy valve

Morphological abnormality with thickened leaflet (diastolic

thickness >5 mm) due to redundant tissue.

Video of MVP





Marfan syndrome

Long redundant anterior leaflet that sags into the LA in

systole.

Subvalvular apparatus

Chordae

Papillary muscles

Rheumatic MR

Commissural fusion

Chordal shortening and fusion are more prominent.

Central jet

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

prolapse.

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

ventricular apex.

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

impinges on

Mitral annulus

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

leaflet.

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.

Ischemic MR

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.

Drugs

Fenfluramine

Pergolide

Cabergoline

Benfluorex

Restriction of leaflet mobility.

EVALUATION

What do guidelines say?

Primary MR

TTE is useful – for evaluation of LV,RV,PAP, mechanism of MR.

Valve disruption or perforation from IE, chordal rupture ,papillary

muscle rupture

Hyperdynamic LV.

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.

Chronic Primary MR

Anatomic

Chambers LV dimensions/size

Left atrial dilation

Left ventricular volume and stroke volume

Flail or perforated leaflet

Doppler

Color flow Jet area

Jet area indexed to left atrium

Central vs eccentric jets

Vena contracta width

Proximal isovelocity surface area Size/qualitative

Volumetric flow/regurgitant volume

Effective regurgitant orifice

Pulmonary vein flow reversal

Spectral Forward flow calculation at the mitral annulus

Signal density

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

closure.

Reverberation from aortic flow.

Normal pulmonary vein flow.

Atrial blood pool motion of overall low velocity

inappropriately visualised because of inappropriate gain and

nyquist limit.

MR when suspected to be confirmed in multiple views.

feigenbaum echo\Fig 12.43

video.flv

Normal posterior motion of blood pool

caused by mitral valve closure Reverberation from aortic flow

feigenbaum echo/Fig 12.43 video.flv

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

contracta).

Flow signal appropriately confined to systole.

Color doppler signal are appropriate in color for the anticipated

direction and/or reveal appropriate variance or turbulence

encoding.

feigenbaum echo\Fig 12.46 video.flv


Differentiation of Primary MR from

Secondary MR

Primary MR

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

room.

Secondary Mitral Regurgitation

Mitral annulus

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

distortion

Unbalance between the increased tethering forces and the decreased

closing forces.

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

(posterior MI)

Seagull sign – traction on the anterior leaflet by secondary chordae.

Symmetric pattern - NICMP,MVD

Seagull sign

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 leaflets body.

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.

Leaflet length.

Distance between the posterior papillary muscle head and the intervalvular fibrosa.

Lateral and posterior displacement of the papillary muscles.

Papillary muscle distance

Sphericity index

Acute vs chronic MR

Acute MR Chronic MR

Etiology Leaflet perforation

Flail leaflet

Papillary muscle rupture

DCMP

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

systole

Pulmonary pressure high normal

LV dimensions normal increased

Eccentric hypertrophy

DOPPLER evaluation…an integrative approach

How to grade Mitral Regurgitation

Mitral Regurgitation

Qualitative

1.Valve morphology

2.Color flow imaging

3.CW doppler

Semi quantitative

1.PW doppler

2.Pulmonary venous flow

3.Vena contracta

Quantitative

1.Doppler volumetric method

2.PISA

Valve morphology

Flail leaflet

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

MR severity.

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.

Imp note.

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

quantification.

Precise quantification is by using vena contracta width and the flow

convergence method.

Color M mode

Apical 4 chamber view

Rheumatic MR does not change in systole or drops

in late systole

Functional MR early and late systole rise

MVP –progressive increase.

Functional MR

Functional MR

Rheumatic MR

MyxomatousMVP

CW doppler

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

severe MR.

Difficult in case of eccentric MR.

V wave cut off sign

Mitral Regurgitation

Qualitative

1.Valve morphology

2.Color flow imaging

3.CW doppler

Semi quantitative

1.Vena contracta

2.PW doppler

3.Pulmonary venous flow

Quantitative

1.Doppler volumetric method

2.PISA

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

contracta measurement.

To note,the respective values of vena contracta width are not

additive for multiple jets.

Pulmonary veins

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

EAE guidelines for evaluation of VHD

2010

Mitral inflow pattern

Qualitative and complementary approach to MR severity.

Semiquantitative

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

Quantitative approaches

Effective Regurgitant Orifice Area (EROA)

Regurgitant volume

Regurgitant fraction

Useful to define the intermediate degrees of MR.

European recommendations for MR quantification have taken

into account the different characteristics of primary and

secondary MR.

EROA

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

significant MR.

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

peak(bimodal pattern).

Functional MR

Functional MR

Rheumatic MR

MyxomatousMVP

SIMPLIFIED

ERO= 0.38R2

MRV=2R2 negative alaising

velocity.

Alaising velocity kept at 30 5 cm/sec

Quantitative volumetric methods

Pulse wave doppler is used.

Flow rates and stroke volumes

SV = TVI annulus CSA annulus

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

regurgitation.

drawbacks

Time consuming

Potential errors that may arise from the multiple

measurements required at different views to calculate RV,

EROA.

Significant training required.

Small errors in measurement are amplified and accurate

resolution of the annulus is important in minimizing

measurement errors.

Mitral Regurgitation severityI (MILD) II III IV(SEVERE)

LV size Normal normal Increased ↑↑

Left atrial size normal normal ↑ ↑↑

MR Jet (% LA) <15 15-30 35-50 >50

Spectral doppler

density

faint - - dense

Vena contracta < 3 mm - - >6 mm

Pulmonary vein

flow

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

Other parameters

LVEF < 55%

DT-E <150 msec

E/E’ (lateral ) >15

PVF-s/PVF-d <0.5

Vp < 45 cm/sec

PASP > 35 mHg

LA size >55 mm

LVDD >70 mm

3D Echocardiography

Better definition of mitral morphology

Pathological changes

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

severity.

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

aliased velocities.

3D PISA

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.

Limitations

Low temporal resolution.

“Volume” or “voxel” rates in real time is low even with small

angles of view.

Stitching artifacts(AF).

Color doppler gain(effect on size,no effect on area)

Instantaneous ROA should be integrated throughout

systole.(midsystole)

Ischemic Mitral Regurgitation

Frequent complication of MI,CAD

Adverse prognosis.

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

ischemia improves)

Chronic MR –secondary to ventricular remodelling due to

IHD –common.

Chronic IMR

Mitral leaflets coapt apically within the LV – restricting

leaflet closure in a pattern known as incomplete mitral leaflet

closure.

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

Regurgitation

Annular dilation can also result in MR

Cleft mitral valve





Consequences of MR

Left ventricle

Left atrium

Pulmonary artery pressure

Right Ventricle

LV

In the chronic compensated phase (the patient could be asymptomatic), the forward stroke volume is maintained through an increase in LV ejection fraction typically >65%.

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.

New parameters

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

velocities.

Strain Imaging

It is not influenced by translation or pathologic tethering to adjacent myocardial segments, which affect myocardial velocity measurements.

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 determined.

LA size and Pulmonary pressures The LA dilates in response to chronic volume and pressure

overload.

A normal sized LA is not normally associated with significantMRunless it is acute, in which case the valve appearance is likely to be grossly abnormal.

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 success.

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.

Key point

Sequential evaluation

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.

Exercise echocardiography

Conclusion.

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.

echocardiographic evaluation of mitral valve disease -mitral regurgitation

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