Non-Invasive Echo Assessment of Valvular Regurgitation Part 1 MR

Dr. Essam El GarhyConsultant Cardiologist - KFMMC

5th ,April 2012

You are now watching: 7 golden rules of echocardiography

1. Echo is an art, so practice!In order for you to become an expert, you need to practice, practice, practice. But how do you know if your reports are true and valid? This question takes us straight to the second rule…

2. Get an adviser to guide your way.Mentors are important for two reasons: Firstly, they can correct and assist you in your clinical judgment. Secondly, they will guide your echo practice.

3. Be interested and always ask “why”.Curiosity is one of the driving factors of successful diagnosticians. always ask why…“Why is the ventricle enlarged?” – “Why is the jet eccentric?” – “Why is RVF poor?” – “Might this be PE ?” etc.

Also: play around! Use abnormal views and see what happens when you manipulate the transducer.

4. You are allowed to talk to the patient!This will ease the patient and make the exam more pleasant.

5. Study cardiology and cardiothoracic surgery.Put yourself into the driving seat of patient management. Your echocardiogram is often key to the treatment strategy.

6. Measure and quantify but only trust reliable values.Everybody likes facts and numbers to base decisions on. However, many studies have found that eyeballing performed by an experienced echocardiographer is just as good, if not better, as a measurement.

7. Store digitally and compare with previous studies!That’s what radiologist do all the time. You can easily miss subtle changes simply based on measurements, which have a large measurement error. Left ventricular function and pericardial effusion are good examples. The eye will give you a better appreciation.

If you can stick to these rules, your echo skills will significantly improve.

Major Factors That Affect Flow Across Any Valvular Lesion

• The valve area

• The square root of the hydrostatic pressure gradient across the valve

• The time duration of transvalvular flow (applies to both systole and diastole)

Valvular Heart Disease

• Increasing any of the major factors that affect flow across the valve increases transvalvular flow.

• Conversely, decreasing any of these major factors decreases transvalvular flow.

Goals in Management of Various Valvular Lesions

• Regurgitant Lesions– Reduce or minimize regurgitant flow across

the mitral or aortic valve.

• Stenotic Lesions– Maximize and enhance stenotic flow across

the mitral or aortic valve

• The valve area in regurgitant lesions can respond to changes in loading conditions (preload, afterload)

• The valve area with stenotic lesions is generally fixed

Goals in Management of Various Valvular Lesions

Mitral Regurgitation • Valve leaflets

• Chordae tendineae• Papillary muscles

• Rheumatic disease• Endocarditis• Mitral valve prolapse• Mitral annular enlargement• Ischemia• Myocardial infarction• Trauma• Fenfluramine diet suppressants

Mechanism of functional mitral regurgitation. A, normal mitral valve. B, ischemic mitral valve with

pronounced posterior restriction in P3 after an episode of ventricular ischemia. LV, left ventricle.

Pathophysiology of Mitral RegurgitationBackward flow of blood from LV to LA (Systolic)

Increased LA volume and

pressure

Increased LV filling(Increased LVEDV)

Increased SV

Blood ejected into aorta

Left atrial enlargement

Increased pulmonary

venous pressures

Pulmonaryedema

Pathophysiology

• LV “unloads” itself into left atrium – Chronic left atrial overload

• Chronic overload on left ventricle

• Volume of regurgitant flow determined by:– Ventriculo-atrial gradient– Diastolic time– Size of the regurgitant orifice

• Measurements of LV function tend to be slightly elevated– Moderately depressed ejection fraction in a patient with MR may

be indicative of a severely depressed inotropic state

MR consequences The consequences of MR on the left ventricle and right ventricle pressures will depend on its acuteness and mechanism. Acute MR-reduction of forward stroke volume -increase in end-diastolic volume → hyperkinetic LV→ reduced LA compliance→ elevation LA pressure→ pulmonary edema→ elevation RVSP Chronic MR- LA dilatation- hyperkinetic LV- LV dilatation (increased diastolic volume)- elevation RVSP

Natural History

HEMODYNAMIC GOALS IN MR:

Preload Increased or Decreased

Best level of preload for an individual patient must be based on their

response to fluid load.

Heart Rate IncreasedIncreased HR leads to a decrease in

LV volume, increased forward flow, and decreased regurgitant fraction.

Contractility Increased or Maintain

Increased contractility tends to increase forward flow and may reduce

regurgitant fraction by constricting mitral annulus.

SVR DecreasedAfterload reduction is helpful in

improving forward flow.

PVR DecreasedFrequently have elevated PA pressures. Avoid acidosis,

hypercarbia, and/or hypoxemia.

Types and Etiology Of MR

TEE (A) and color Doppler flow (B) from a 27 year-old man, with Marfan syndrome. Note severe mitral valve regurgitation from: annulus dilatation, lengthening of the chordae tendineae and a redundancy of the leaflets, especially of the posterior one.

Marfan syndrome

(A) In normal mitral valve, the coaptation (red point) occurs beyond the mitral annular plane (line); (B) billowing mitral valve is observed when a part of the mitral valve body protrudes into the left atrium (arrow); (C and D) mitral valve prolapse is defined as abnormal systolic displacement of one (C: posterior prolapse) or both leaflets into the left atrium below the

annular (D: bileaflet prolapse); (E) flail of the anterior leaflet (arrow).

Lancellotti P et al. Eur J Echocardiogr 2010;11:307-332

Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2010. For permissions please email: journals.permissions@oxfordjournals.org

Transthoracic echocardiography:

parasternal long axis view from a patient with isolated mitral valve cleft: note preoperative severe mitral valve regurgitation (on color flow Doppler: the regurgitant jet passes through the cleft of   the anterior mitral valve leaflet, and it is directed posteriorly) (A); and postoperative, after repairing the cleft, a mild mitral valve regurgitation (B).

Adult patient with severe mitral valve regurgitation on shortened cordae tendineae (note: posterior mitral leaflet with limited mobility - arrow, and eccentric regurgitant jet orriented to posterior atrial wall)

AS

Parasternal long axis view with colour M mode Doppler echocardiography from a patient with hypertrophic cardiomyopathy and a high (90 mmHg) outflow tract gradient.

Prasad K et al. Heart 1999;82:III8-III15

Copyright © BMJ Publishing Group Ltd & British Cardiovascular Society. All rights reserved.

Assessment of the severity of MR

Quantitative parametersVena contracta ( VC )Regurgitant Volume (RV)Regurgitant Fraction (RF%)Effective Regurgitant Orifice Area (ERO)

Visual assessment of MR jet using colour-flow imaging

Lancellotti P et al. Eur J Echocardiogr 2010;11:307-332

Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2010. For permissions please email: journals.permissions@oxfordjournals.org

A vena contracta 3 mm indicates mild MR whereas a width ≥7 mm defines severe MR. Intermediate values are not accurate at distinguishing moderate from mild orsevere MR (large overlap); they require the use of another method for confirmation.

VCWidth (mm)

TVITVI MV /TVI AV

EROA mm2

R V mL

E m/s MV

inflow

MILD < 3 <1 < 20 < 30 A wave dominate

SEVERE >=7 >1.4 >=40 >=60E wave

> 1.5 m/s

Moderate MRMild to moderate

• EROA

20 – 29 mm2

• R Vol

30- 44 mL

Moderate to severe

• EROA

30-39 mm2

• R Vol

45-59 mL

Grading organic MR severity

In severe MR, CWD signal of the MRJ is truncated, triangular and intense . Notching of the continuous wave envelope (cut-off sign) can occur in severe MR.

TVI MV/AV

0.7

TVI MV/AV

1.0

TVI MV/AV

1.7

(A)Normal pulmonary vein flow pattern; (B) Blunt forward systolic pulmonary vein flow in a

patient with moderate MR; (C) Reversed systolic pulmonary flow in a patient with

severe MR.

Quantitative assessment of MR severity using the proximal isovelocity surface area method.

Lancellotti P et al. Eur J Echocardiogr 2010;11:307-332

Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2010. For permissions please email: journals.permissions@oxfordjournals.org

Stepwise analysis of MR: (A) Apical four-chamber view (B) colour-flow display; (C) zoom of the selected zone; (D) downward shift of zero baseline to obtain an hemispheric proximal isovelocity surface area; (E) measure of the proximal isovelocity surface area radius using the first aliasing; (F) continuous wave Doppler of MR jet allowing calculation the effective regurgitant orifice area (EROA) and regurgitant volume (R Vol).

TVI, time-velocity integral.

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)

To avoid the underestimation of the regurgitantvolume the ratio of the aliasing velocity (Va) to peak orifice velocity (vel) is maintained <10%.

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

4 examples of flow convergence zone changes during systole using colour M-Mode. (A and B) Functional mitral regurgitation(A: early and late peaks and mid-systolic decreases; B: early systolic peak), (C) rheumatic mitral regurgitation with a end-systolic decrease in flow convergence zone, (D) M mitral valve prolaspe (late systolic enhancement).

Illustration of the variation of the PISA and hence ERO during systole. In early and late systole, closing forces are relatively low and so the ERO and PISA relatively large. In midsystole, coincident with peak regurgitant velocity closing forces are maximal and so the ERO and PISA contract as the tips of the leaflets are forced closer together.

CW Doppler of MRJ Peak MR jet velocities by CW Doppler typically range between 4and 6 m/s. This reflects the high systolic pressure gradient between the LV and LA.

The velocity itself does not provide useful information about the severity of MR. Conversely, the signal intensity (jet density) of the CW envelope of the MR jet can be a qualitative guide to MR severity.

A dense MR signal with a full envelope indicates more severe MR than a faint signal. The CW Doppler envelope may be truncated (notch) with a triangular contour and anearly peak velocity (blunt).

This indicates elevated LA pressure or a prominent regurgitant pressure wave in the LA due to severe MR.

In eccentric MR, it may be difficult to record the full CW envelope of the jet because of its eccentricity, while the signal intensity shows dense features.

CW Doppler Assessment of MR• Shape: symmetrical or asymmetrical

Chronic vs. Acute MR

• Density of signal

Consequences of mitral regurgitation

The presence of severe MR has significant haemodynamic effects, primarily on the LV , LA and SPAP .

LV size and function

The LV dimensions and EF reflect the heart’s ability toadapt to increased volume load.

In the chronic compensated phase (the patient could be asymptomatic), the forward SV is maintained through an increase in LVEF . Such patients typically have LV EF 65%.

In the chronic decompensated phase (the patient could still be asymptomatic or may fail to recognize deterioration in clinical status), the forward SV decreases and the LAP 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.

current guidelines, surgery is recommended in asymptomatic patients with severe organic MR when the LV ejection fraction is ≤60%.

In the end-systolic diameter .45 mm (or ≥40 mm or .22 mm/m2, AHA/ACC), also indicates the need for mitral valve surgery.

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.

Left atrial size and pulmonary pressures

The LA dilates in response to chronic volume and pressure overload.A normal sized LA is not normally associatedwith significantMR unless it is acute, in which case the valve appearance is likely to be grossly abnormal.

LA remodelling (diameter 40–50 mm or LA volumeindex .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 PASP is 50 mm Hg at rest.

Key point

When MR is more than mild MR, providing LVD , LVV , LVEF as well as the LAD (preferably LAV) and the PASP in the final echocardiographic report is mandatory.

The assessment of regional myocardial function (systolic myocardial velocities, strain, strain rate) is reasonable particularly in asymptomatic patients with severe organic MR and borderline values in terms of LV EF(60–65%) or LV ESD (closed to 40 mm or 22 mm/m2).

Copyright ©2009 American College of Cardiology Foundation. Restrictions may apply.

Picano, E. et al. J Am Coll Cardiol 2009;54:2251-2260

Exercise Echo in

Ischemic MR

Exercise Echocardiography in Ischemic Mitral RegurgitationApical 4-chamber views of color-flow Doppler and proximal flow-convergence region (left panels) are shown in a patient with ischemic mitral regurgitation (MR) along with the systolic tricuspid regurgitation velocity (right panel). With exercise, there is a major increase in both the severity of mitral regurgitation and the estimated pulmonary artery systolic pressure. ERO = effective regurgitant orifice measured by the proximal isovelocity surface area; R Vol = regurgitant volume; TTPG = systolic transtricuspid pressure gradient.

Key pointExercise echocardiography is useful in asymptomaticpatients with severe organic MR and borderline values ofLV ejection fraction (60–65%) or LV end-systolic diameter(closed to 40 mm or 22 mm/m2). The absence of contractilereserve could identify patients at increased risk of cardiovascular events. Moreover, exercise echocardiographymay also be helpful in patients with equivocal symptomsout of proportion of MR severity at rest.

Echocardiographic parameters used to

quantify MR severity ,recording ,

advantages and limitations

Parameters Recording Usefulness/Advantages

Limitations

MV Morphology

• Visual assessment

• Multiple views

• Flail valve or ruptured PMs are specific for significant MR

Other abnormalities

are non-specific of

significant MR

Colour – flow MR jet

• Optimize colour gain / scale

• Evaluate in two views

• Need BP evaluation

• Ease of use • Evaluate the spatial orientation of MRJ• Good screening test for mild vs severe MR

• Can be inaccurate for estimation of MR severity • Influenced by technical and hemodynamic factors • Underestimate eccentric jet

Parameters Recording Usefulness/Advantages

Limitations

Vena Contracta

( VC ) width

• 2 orthogonal planes PT-LAX ,AP-4CV• Optimize colour gain / scale • Identify the 3 components of MRJ VC,PISA,MRJ in LA• Reduce the colour sector size and imaging deapth to maximum frame rate • Zoom • Use the cine – loop to find the best frame for measurement • Measure the smallest VC

•Relatively quick and easy

• Relatively independent of hemodynamic and instrumentation factors • Not affected by other valve leak • Good for extremes MR mild vs severe • Can be used for eccentric jet

• Not valid for multiple jets

• Small values , small errores lead to large %error

• Intermediate values need confirmation

• Affected by systolic changes in regurgitant flow

Parameters Recording Usefulness/Advantages

Limitations

PISA Method

•AP-4CV•Optimize CFI of MR •Zoom the image of the MR Valve •Decrease the Nyquist limit (CF zero baseline)•With the cine mode select the best PISA •Display the colour off and on to visualize the MRO•Measure the PISA radius at mid systole •Measure MR peak velocity and TVI (CW )•Calculate flow rate ,EROA, R Volume

• Can be used in eccentric jet

• Not affected by aetiology of MR or other valve leak • Quantitative estimate lesion severity ( EROA )

• Quantitative estimate volume overload R Volume

• Flow convergence at 50 cm/s alerts to significant MR

•PISA shape affected by:-─Aliasing velocity─Non circular orifice─ Systolic changes in regurgitant flow─Adjacent structure •PISA is more a hemi-ellipse

•Errors in PISA radius measurements are squared •Inter – observer variability •Not valid for multiple jets

Parameters Recording Usefulness/Advantages

Limitations

Doppler Volumetric

Method ( PW )

Flow across the

MV( AP- 4CV )

• Measure the mitral inflow by placing the PW sample volume at

MV annulus

• Measure the MV annulus diameter at the maximal opening of the MV ( 2-3 frames after the end – systole )

• Quantitative

estimate lesion severity (EROA )

And

Volume overload = RV

• Valid in multiple jets

•Time consuming •Requires multiple measurements sources of errors • Not applicable in case of significant AR ( use PVF )

• Difficult to asses MAD and MV inflow in case of calcific MV or MAC

•Affected by SV location MV inflow

Parameters Recording Usefulness/Advantages

Limitations

Doppler Volumetric

Method ( PW )

Flow across the

AV

• Measure the LVOT flow by placing the PW SV 5 mm below the aortic cusp (AP – 5 CV )

• Measure the LVOT diameter ( PT-LAX View )

• Quantitative

estimate lesion severity (EROA )

And

Volume overload = RV

• Valid in multiple jets

•Time consuming •Requires multiple measurements sources of errors • Not applicable in case of significant AR ( use PVF )

• Difficult to asses MAD and MV inflow in case of calcific MV or MAC

Parameters Recording Usefulness/Advantages

Limitations

CW MR jet profile A 4 CV Simple , easily

available • Qualitative , complementary finding

• Complete signal difficult to obtain in eccentric jet

Peak E velocity • Apical 4 – CV

• SV of PW places

at MV leaflet tips

• Simple , easily available

• Dominant A- wave almost exclude severe MR

• Affected by LAP ,AF, LV relaxation •Complementary finding

Parameters Recording Usefulness/Advantages

Limitations

Pulmonary vein flow

• A 4 CV SV of PW places into the Pulmonary Vein

• Interrogate the different PV when possible

• Simple

• Systolic flow reversible is specific for severe MR

• Affected by LAP and AF

• Not accurate if MRJ directed into sampled vein

LA and LV size

Use preferably the Simpson method

• Dilatation sensitive for chronic significant MR

• Normal size almost exclude chronic significant MR

• Dilatation observed in other conditions ( non-specific )

• May be normal in acute MR

MCQs

In patients with MR and AF the most reliable method for assessment of severity are the following except :

• VC width and or PISA method

• Color – flow MRJ

• PVF and Peak E velocity

In patients with MR and AF the most reliable method for assessment of severity are the following except :

• VC width and or PISA method

• Color – flow MRJ

• PVF and Peak E velocity

In patients with MR and significant AR the most reliable method for assessment of severity are the

following except :

• VC width and or PISA method

• Doppler Volumetric method PW

• Color – flow MRJ

In patients with MR and significant AR the most reliable method for assessment of severity are the

following except :

• VC width and or PISA method

• Doppler Volumetric method PW

• Color – flow MRJ

In patients with MR eccentric jet the method which can be used for

assessment of severity is :

• VC width and or PISA method

• Doppler Volumetric method ( PW )

• Color – flow MRJ

In patients with MR eccentric jet the method which can be used for

assessment of severity is :

• VC width and or PISA method

• Doppler Volumetric method ( PW )

• Color – flow MRJ

• VC width

• PISA method

• Doppler Volumetric method PW

• Color – flow MRJ

In patients with multiple jets the valid method for assessment of severity is :

In patients with multiple jets the valid method for assessment of severity is :

• VC width

• PISA method

• Doppler Volumetric method PW

• Color – flow MRJ

• Mild MR• Moderate • Moderate to severe • Severe

In patient with MR and VC = 5 mm TVI Mit /TVI Ao =1.2 EROA= 25 mm2 Rvol 35 Ml the severity is :

In patient with MR and VC = 5 mm TVI Mit /TVI Ao =1.2 EROA= 25 mm2 Rvol 35 Ml the severity is :

• Mild MR

• Moderate

• Moderate to severe

• Severe

In patient with MR and VC = 6 mm TVI Mit /TVI Ao =1.4 EROA= 35 mm2 Rvol 75 mL the severity is :

Mild

Moderate

Moderate to severe

Severe

In patient with MR and VC = 6 mm TVI Mit /TVI Ao =1.3 EROA= 35 mm2 Rvol 55 mL the severity is :

Mild

Moderate

Moderate to severe

Severe

Mitral regurgitation

Simultaneous pressure recordingHigh LVEDPGiant V wave max Pressure 85 mmHgSystolic PG LV-LA =15 mmHg

What cardiac catheterization will

give us more informations in MR ?

Thank you