123 sonography prosthetic valves assesment

7/23/2019 123 Sonography Prosthetic Valves assesment

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Type of Valves

Mechanical Valves

Metal case/occluders

Types: ball cage, tilting disc,bileaflet

NOTE:Mechanical

Anticoagulation necessary

younger

High durability

pa en s

Composite graft (prosthesis +aortic root replacement)

Types of Mechanical Valves Few Exa ples

Manufacture Model Year

Ball Baxter Starr-Edwards 1965

Disk Medtronic Medtronic Hall 1977

Medical Omniscience 1978

Alliance Monostrut 1982

Bileaflet St. Jude St. Jude 1977

Baxter Edwards Duromedics 1982

Carbomedics Carbomedics 1986

Sorin Biomedica Sorin Bicarbon 1990

Biological Valves

Ring (Struts)/ stentless valve

No anticoagulation NOTE:

Less durable than mechanicalvalves

for the elderly(but not

Homograft (cadaver)

Autograft (pulmonic valve) Ross OP

014 // Prosthetic Valves

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Types of Biological Valves Few Exam les

Type Manufacture Model Year

Porcine Medtronic Hancock Standard 1970

Hancock MO 1978

Baxter Edwards CE Standard 1971

Baxter Edwards CE Supraannular 1982

St. Jude Toronto Stentless 1991

Medtronic Stentless Freestyle 1992

Pericardial Baxter Edwards CE 1982

Echo Assessment of Prosthetic Valves

Assessment of Valve Pros thesis NOTE:

Morphology!on orge o

look at the

Gradients

ventricle andsPAP in mitral

Color Doppler

valveprosthesis!!

Flow Patterns in Mechanical Valve P ro sthesis

Forward flow Physiologic regurgitation

Bileaflet Prosthesis

Tilting Disc

Tilting Disc (Medtronic Hall)


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Common Findings

Residuals of subvalvular apparatus Cavitations

Abnormal septal motion Normal regurgitations

Image Problems in Pa ients with Mechanical Valves

Artefacts Shadowing

Decreased visibility of LA(MV prosthesis)

Decreased visibility ofregurgitant jet

Difficult diagnosis ofendocarditis

Thrombi visualizationdifficult

Difficult to see leaflet motion Flow convergence?

NOTE: In TEE atrial side is visible. Use therefore if in d ubt both, TTE and TEE!

Reference Values for Pr sthetic Aortic Valves

Bioprosthesis Vmax (m/s)Grad.max(mmHg)

Grad. mean(mmHg)

Carpentier-Edwards 2.37 0.46 23.18 8.72 14.4 5.7

Hancock 2.38 0.35 23.0 6.71 11.0 2.29

Mitroflow 2.0 0.71 17.0 11.31 10.8 6.51

Stentless bioprosthesis(25mm)

Vmax (m/s)Grad.max(mmHg)

Grad. mean(mmHg)

Biocor Stentless 2.8 0.5 28.65 6.6 17.72 6.35

Medtronic Freestyle 5.35 1.5

Toronto Porcine 1.74 1.19 38.6 11.7 24 4

Mechanical prosthesis Vmax (m/s)Grad.max(mmHg)

Grad. mean(mmHg)

St. Jude Medical 2.37 0.27 25.5 5.12 12.5 6.35

Bjrk-Shiley 2.62 0.42 23.8 8.8 14.3 5.25

Starr-Edwards 3.1 0.47 38.6 11.7 24.0 4.0

NOTE: Consider prosthe

!> 3 m/s and the mean

tic aortic valve

radient is!

>

dysfunction if the

0mmHG

aximal velocity is


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Reference Values for Prosthetic Mitral Valves

Bioprosthesis Vmax (m/s)Grad.max(mmHg)

Grad. mean(mmHg)

PHT (ms)

Hancock 1.54 0.26 9.7 3.2 4.29 2.14128.6

30.9

Carpentier-Edwards

1.76 0.24 12.49 3.64 6.48 2.1289.8 25.4

Ionescu-Shiley 1.46 0.27 8.53 2.91 3.28 1.1993.3 25.0

Mechanical

prosthesis Vmax (m/s)

Grad.max

(mmHg)

Grad. mean

(mmHg) PHT (ms)

St. Jude Medical 1.56 0.29 9.98 3.62 3.49 1.3476.5

17.1

Bjrk-Shiley 1.61 0.3 10.72 2.74 2.9 1.6190.2 22.4

Starr-Edwards 1.88 0.4 14.56 5.5 4.55 2.4109.5

26.6

NOTE: Consider pr!> 2 m/s and the

osthetic mitralean Gradient i

alve dysfunctis !> 8mmHG

on if the maximal velocity is

Effective Orifice Area NOTE:

VTI of AV velocity

orifice area

Stroke volume LVOT

effective

orifice

area!!

Pressure Recovery

Leads to overestimation ofgradients by doppler

NOTE:

Nobody

Relevant in small aortic root(


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Prosthesis Mismatch

Indexed effective orfice area < 0.85cm2/m2

Calcified aortic annulus Increased late mortality

Setting of LV dysfunction

Complications

Mechanical Valve Compl ications

Left ventricular failure Paravalvular leaks

Valve obstruction Thrombus/Pannus

Endocarditis Mechanical failure

Biological Valve Com plications

Left ventricular failure Paravalvular leaks

Valvular regurgitation Valve obstruction

Degenerative changes Endocarditis

Predisposing Factors for Structural Failure in Bioprosthesis

Renal failure Hemodialysis

Hypercalcemia Adolecent (growing)

Porcine > pericardial


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Bioprosthesis Obstruction Echo Findings

Thickened calcified leaflets Reduced mobility

Elevated gradients PHT (MV-prosthesis)

Turbulent flowSize of prosthesis (DD:mismatch)

When implanted?

NOTE: Compair with p evious studies and initial post-operative gradients!

Mechanical Valve Obstruction Echo Findings

Impaired/stuck leafletEchogenicity in valve region(thrombus?)

Pathologic flow pattern Elevated gradients

PHT (MV)

NOTE: Use Fluoroscopy to detect mechanical valve obstruct on!

Mechanical Valve Obst uction Pannus vs. Thro bus

Pannus Thrombus

INR normal INR low

Slow onset of symptoms Sudden symptom onset

Age of prosthesis Stroke/ embolism

Stable gradients Variable gradients

NOTE: In reality, often nly the surgeon can give us the answer!


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Quantification of Obstr uction

Aortic Valve Prosthesis Mitral Valve Prosthesis

Morphologic findings Morphologic findings

Symptoms Symptoms

Velocity > 3.0 m/secMean gradients(>6-8 mmHg)

DVI < 0.3 (0.25) PHT > 130ms

NOTE: Use color Doppl

valve)! Use several win

er to guide the position o

ows to quantify prosthet

the CW Doppler (mitral

c aortic valve obstruction!

Regurgitation i Valve Prosthesis

Normal/physiologic

Pathologic (paravalvular) Some degree of

Valvular/ structural failure (bio)

regurgitation is

Valvular/ mechanical failure (mech)

Paravalvular Regurgitation

Prevalence: 6- 32% early, 7- 10% late Patients with

AVP > MVP Small atria paravalvular

Determinents: Calcified annulus, endocarditis, suturetechnique

regurg a on o en

have hemolysis!

Echo Evaluation of Regurg itation

Multiple/atypical views

Eccentric jets!

Short axis

CW- Doppler

Gradients


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Elevated Gradients Co nsiderations

Compare with baseline/normal values!!!

INR/ medical history/follow up!

Regurgitation? Mismatch?

Obstruction Flow?

NOTE: An elevated gradi

obstruction. A normal P

significant regurgitation.

nt in MV prosthesis with a hi

T in the setting of elevated g

Use TEE for further quantific

gh PHT indicates an

radients indicates a

tion!!

Other Complications

Valve dehiscence Look for rocking valve motion!

PseudoaneurysmEndocarditis predisposes, native andprosthetic AV, fistula LV to LVOT

Iatrogenic VSD Rare complication

TR after MV surgeryPredisposing factors: Pulmonaryhypertension, annular dilatation,Afib, prior degree of TR

Endocarditis (See also Chapter 15)

3-6 % cumulative risk/5 years

Bio > mechanical valves

Difficult to detectRegurgitation andobstruction

NOTE: TEE assessment is

endocatditis!

of utmost importance in patients with suspected


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Mitral Valve Repair

Mitral Valve Repair - ingimplantation (Annuloplasty)

Different types of rings Mitral valvere air is

Prevents annular dilatation

always

combined

Always in primary and secondary MR

with ring

implantation!

Common Techniques of itral Valve Repair

Annuloplasty(see above)

Quadrangular/Triangularresection (with/withoutsliding plasty)

Chordal transfer Artificial Chords

Complications of MV Repai r

Residual regurgitation Obstructed LV inflow

Ring dehiscence(partial dehiscence, originoutside of ring)

LVOT obstruction/SAM(redundant leaflets, smallhyperdynamic LV, small annulus)


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123 sonography prosthetic valves assesment

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