Valvular regurgitation - mitral

Definition: MR

• AKA

• CAUSED BY

• Leaking of the mitral valve during systole from left ventricle to left atrium

• Also known as mitral insufficiency

• Due to incomplete closure of the mitral valve

decreased heart function causes what for regurge

decreased regurgitation but thick envelope

most common symptom of MR

MURMUR

• Blowing

• high pithed

• holosystolic

• cardiac apex radiates to axilla

MR can eventually lead to

Right heart failure due to backup in the pulmonary veins into the RA Increasing PAP

• TOO MUCH VOLUME

Etiology MR: Causes (6)

• Primary Mitral Regurgitation

• Functional Mitral Regurgitation

• Flail mitral valve leaflet

• Papillary muscle rupture

• Left ventricle

- ischemia, infarction, cardiomyopathy

• Mitral Valve Apparatus

MR Increases PRELOAD which causes the LV to become

hyperdynamic

WHAT VIEW IS MVP MITRAL VALVE PROLAPSE DIAGNOSED FROM ONLY!!!

PLAX!!! ONLY!!!

FLAIL MV

• Severe regurgitation

• leaflet fails to coap usually due to pap or chordae problem

• leaflet goes back into LA

• JET GOES IN DIRECTION OPPOSITE OF AFFECTED VALVE

Barlows syndrome

MV problems from fibrous disease

• primary MR

Primary Mitral Regurgitation

• problem with

problem with the leaflets

causes of primary MR (4)

o Mitral valve prolapse

o Endocarditis

o Rheumatic heart disease

o Mitral annular calcification

causes of Functional Mitral Regurgitation (4)

• Ischemic mitral regurgitation due to ischemia or cardiomyopathy

• Flail mitral valve leaflet

  • Papillary muscle rupture

  • Left ventricle - ischemia, infarction, cardiomyopathy

MV Apparatus

• any problem with these will cause MR

• Left atrial wall

• Mitral annulus

• Anterior and posterior leaflets

• Chordae

• Papillary muscles

• Left ventricular myocardium underlying the papillary muscles (tenting)

• Normal closure of the valve is at the annulus

Auscultation / Heart sound MR

High-pitched, blowing holosystolic murmur

Diseases of MV (6)

• Myxomastous Disease - MV Prolapse

• Rheumatic Disease

• Endocarditis

• Marfan Syndrome

• Ischemic MR

• Pap muscle rupture

Myxomatous disease – Mitral Valve Prolapse (5)

o Thickened, redundant leaflets and chordae

o Excessive motion and sagging into the left atrium in systole

o Mitral valve prolapse – minimal leaflet displacement

o Flail mitral valve leaflet – severe leaflet displacement

o Mid systolic click and mid-to-late systolic murmur

Rheumatic Disease

Thickening of the leaflet tips and restricted motion

Endocarditis

Thickening of the leaflet tips and restricted motion

Marfan Syndrome

Long, redundant anterior leaflet that sags into the LA in systole

Ischemic MR

• functional MR

• Caused by

• Relationship to MI

• What happens with PAP rupture

• what can happen to MV leaflets

• due to:

• results in _____ of leaflets

• MR is due to:

• MV

o Functional mitral regurgitation – the leaflets are normal – includes mitral regurgitation caused by ischemia and dilated cardiomyopathy

o Cause by papillary muscle displacement and dilation of the annulus

o Most common complication of an MI

o Severe mitral regurgitation can occur with papillary muscle rupture

o Tenting of the mitral valve leaflets (normal closure is at the annulus)

o Due to regional wall motion abnormalities or dysfunction

o Restricted leaflet motion – abnormal valve closure

o Results in apical displacement (“tenting”) and incomplete closure of the valve leaflets (normal mitral valve closure should be at the annulus)

o Mitral regurgitation is due to left ventricular distortion and annular dilation

o Mitral valve bend is caused by the basal chord

Papillary muscle rupture (Partial rupture of the papillary muscle)

• Comlication of :

• results in

• prognosis

o Complication of an acute myocardial infarction

o Acute, severe mitral regurgitation

o Poor survival

Ischemic MR caused by (6)

• PAP Muscle displacement and dilation of the annulus

• PAP rupture

• regional WMA

• Restricted leaflet motion-abnormal valve closure

• LV Distortion

• Annular dilation

What is the MC complication of MI

Ischemic MR

Pap muscle rupture can cause

severe MR

`Where is normal closure of MV leaflet tips

Annulus

What is it called when the MV closes distal to the annulus

tenting

tenting is _______ displacement which causes:

apicical displacement which causes incomplete closure

MV Bend is caused by what

basal chord

MR is due to

LV Distortion & annular dilation

The response to chronic volume overload on a chamber is

dilation with normal pressure

The response to acute volume overload on a chamber is

no dilation with marked increase in pressure

The initial response of the left ventricle to mitral regurgitation is

LV becomes hyperdynamic

Chronic mitral regurgitation

• progression

• wall thickness

• affect on systolic function

• LA

• PAP

o Progressive left ventricular dilation

o Normal left ventricular wall thickness

o Irreversible decrease in systolic function in the absence of symptoms

o Left atrium gradually dilates with normal left atrial pressure

o Pulmonary artery pressure increases

intermitant MR

• Due to ischemia

• pap displacement

• comes back to normal when ischemia is corrected

Acute mitral regurgitation

• LA

  • Size/pressure

o Normal left atrial size

o Significant increase in left atrial pressure

• can result in flail MV Leaflet

Two-Dimensional Evaluation: MR (5)

• Obtain careful, high-resolution imaging focusing on the mitral valve, chords and papillary muscles in both harmonics and fundamental modes in the parasternal and apical views

• Use magnification (zoom)

• Evaluate for flail mitral valve leaflet, mitral valve prolapse, mitral annular calcification

• Evaluate left atrial size

• Left Ventricle

How to evaluate LV 2D (3)

• Left Ventricle

o Evaluate left ventricular size and function - volume overload pattern

o Obtain end-systolic dimension

o Surgery needed with an end-systolic dimension greater than 45 mm and reduction in systolic function

Color Doppler Evaluation: (3)

• color doppler jet

• eccentric or central

• vena contracta width

Color Doppler Jet Area

• scale

• settings

• views

• jet (2)

o Normal Color Doppler Nyquist Limit Setting: 50 – 60 cm/s

o Correct color Doppler gain

o Parasternal and apical views

o Length of mitral regurgitation jet

o Area of jet –

▪ Less than 20% of the left atrial area indicates mild mitral regurgitation

▪ Greater than 40% of the left atrial area indicates severe mitral regurgitation

o Area of jet –

▪ Less than 20% of the left atrial area indicates mild mitral regurgitation

▪ Greater than 40% of the left atrial area indicates severe mitral regurgitation

Eccentric or central

▪ The severity of mitral regurgitant jets that hug a wall is underestimated

– it is more severe than appears due to the Coanda Affect (the jet stays attached to the curved surface, i.e., left atrial wall).

▪ Henri-Marie Coanda – Romanian aerodynamicist

o Timing (early, mid, late) and duration

▪ Mitral valve prolapse will produce late systolic mitral regurgitation

Vena Contracta Width

• where is the narrowest portion

• what view

• how to RES

• mild

• severe

o The narrowest portion of the color Doppler jet at the leaflet tips

o Parasternal long axis view - perpendicular to flow

o Magnify

o Mild = less than < 0.3 cm

o Severe = greater than 0.7 cm

Mitral Valve Inflow Doppler (LV Inflow)

o E velocity greater than 1.2 meters per second may indicate significant regurgitation with EF greater than 40%

o Deceleration time less than 150 milliseconds may indicate significant regurgitation

Continuous-Wave Doppler

o The jet is wider than the aortic stenosis jet – starts earlier

o More severe mitral regurgitation will produce a Doppler waveform that is complete and dark and triangular shaped

Pulmonary Venous Doppler

o Obtain color-guided pulsed-wave Doppler of the right upper (superior) pulmonary vein

o Lower color Doppler scale

o Increase color Doppler gain slightly

o Place sample volume

o Reduce wall filter

o Flow reversal in the right superior pulmonary vein is seen with severe mitral regurgitation

Proximal Iso-velocity Surface Area (PISA)

• Based on the concept that the flow proximal to the regurgitant orifice is equal to the flow through the regurgitant orifice

How to measure PISA

• A4C or A3C

• 40 FPS

  • Zoom MV, Tight color box

• Baseline towards jet

  • 80 top #

  • 30 bottom #

  • REMEMBER TO CHANGE IT BACK

• Freeze mid systole 20 - 40 cm/s

• Measure radius of aliasing velocity of vena contracta

scale set to ____ for MR Spectral doppler

6 m/s

What you need to measure: PISA

1. VTI of mitral regurgitation CW Doppler jet

2. PISA Radius

3. Aliasing Velocity

Procedure for PISA (5)

o Magnify on the color Doppler PISA

o Shift the color baseline downward (toward the jet) to decrease the color flow aliasing velocity (between 25 – 40 cm)

o Measure the radius of aliased region - the distance of the isovelocity shell from the orifice

o Note the alias velocity on the color bar (cm/s)

o VTI of mitral regurgitation continuous-wave Doppler jet (cm)

how to distringuish MR from Ao flow in Spectral doppler

TIMING!

• MR ocurrs earlier than aortic flow

steep / fast deceleration time =

high pressure gradient

Regurgitant Volume (RV):

• defintion

• equations (3)

o the amount of blood that leaks back into the left atrium per beat o ml/beat

o RV = SV_mr – SV_lvot

o SV = CSA x VTI

o CSA = π(D/2)² or 0.785 x (D)²

RV =

o RV = SV_mr – SV_lvot

SV =

SV = CSA x VTI

CSA = (2)

o CSA = π(D/2)²

or 0.785 x (D)²

Regurgitant Fraction (RF):

The percentage of blood that leaks back into the left atrium per beat

Regurgitant Orifice Area (ROA): def

The area (cm²) of the hole or defect through which the blood leaks

Regurgitant Orifice Area (ROA): eq

ROA = RV/VTI_MR

Mild Mitral Regurgitation:

• Jet area less than 20% of LA area

• Vena contracta width < 0.3 cm

• Very little or no flow convergence - PISA radius < 0.4 cm

• Light, not complete spectral Doppler signal

• Regurgitant Volume < 30 ml/beat

• Regurgitant Fraction <30% • Effective Regurg

Mitral E velocity (m/s)

• mild

• moderate

• severe

• mild

  • <1.3 m/s

• moderate

• severe

  • >1.2 m/s

Vena contracta width (cm)

• mild

• moderate

• severe

• mild

  • < 0.3 cm

• moderate

  • 0.3 - 0.7 cm

• severe

  • >0.7 cm

Flow convergance

• mild

• moderate

• severe

• mild

  • minimal or none

• moderate

• severe

  • large

PISA Radius

• mild

• moderate

• severe

• mild

  • <0.4 cm

• moderate

• severe

  • ≥ 0.9 cm

Spectral doppler waveform

• mild

• moderate

• severe

• mild

  • light, may not be complete, parabolic

• moderate

• severe

  • Dark stained, triangular

Pulmonary vein

• mild

• moderate

• severe

• mild

  • no reversal

• moderate

• severe

  • Flow reversal

Jet area %

• mild

• moderate

• severe

• mild

  • <20% of LA

• moderate

• severe

  • >40% of LA

Regurgitation volume (mL/beat)

• mild

• moderate (2)

• severe

• mild

  • <30 mL/beat

• moderate

  • 30 - 44 mL/beat

  • 45 - 59 mL/beat

• severe

  • >60 mL/beat

Regurgitation fraction (%)

• mild

• moderate (2)

• severe

• mild

  • < 30%

• moderate

  • 30 - 39%

  • 40 - 49%

• severe

  • ≥ 50%

Effective regurgitation oriface area (cm²)

• mild

• moderate

• severe

• mild

  • < 0.20 cm²

• moderate

  • 0.20 - 0.29 cm²

  • 0.30 - 0.39 cm²

• severe

  • ≥ 0.40 cm²

LA size

• mild

• moderate

• severe

• mild

• moderate

• severe

  • enlarged

LV Size

• mild

• moderate

• severe

• mild

  • Normal

• moderate

• severe

  • Englarged

Severe MR

• Increased inflow velocity – E wave greater than 1.2 meters per second

• Reversed systolic flow in pulmonary veins

• Dilated left atrium and left ventricle

• Hyperdynamic left ventricle

• Eventually will develop left ventricular dilation

• Color Doppler jet area greater than 40% of LA area

• Vena contracta width greater than 0.7 cm

• Large flow convergence (PISA radius) ≥ 0.9 cm (aliasing velocity at 40 cm/s)

• Dense spectral Doppler waveform, triangular-shaped spectral Doppler waveform

• Regurgitant Volume ≥ 60 ml/beat

• Regurgitant Fraction ≥ 50%

• Effective Regurgitant Orifice Area ≥ 0.40 cm²

when is surgery required for MR

• End-systolic dimension >45 mm

AND

• Reduced systolic function

surgical options for MR

• Valve replacement

• angioplasty / revascularization

• valve repair

  • annular ring / annuloplasty

  • mitra clip

    • like a staple in the middle of the valve

    • 2 jets but less regurgitation

Normal PW doppler of pulmonary vein

• systolic dominance

blunted systolic pulm vein flow

• moderate

superior pulm vein flow reversal

• BAD