Prosthetic Valves Flashcards
Types of aortic bioprostheses
Cadaveric homograft
Autograft (Ross)
Stented / stentless xenografts
Aortic cadaveric homograft
Bioprosthetic, rare
Looks like regular valve
None to trivial central regurgitation
Stented / stentless aortic bioprostheses
Porcine Pericardial Bovine Stented - see seats on echo Stentless Transcatheter
Normal bioprosthetic valve regurgitation
No or trivial central regurgitation
Mechanical aortic bioprostheses
Caged ball
Single tilting disc
Bileaflet
Mechanical prosthesis regurgitation
Built-in washing jets with prosthetic regurgitation
Aortic caged ball
Ball going up and done in cage
Aortic single tilting disc
Single disc going up and down
Big puff of central regurgitation
Aortic bileaflet mechanical valve
Most common
Two occluders / leaflets open up and down, don’t go to 90’
Central and side jets
Periprosthetic regurigtation
Always pathologic
Assessment of aortic prosthetic stenosis
2D and doppler variables
EOA by continuity equation
Normal ranges
Correct measurement of LVOT VTI and LVOT diameter
Aortic homograft normal MG
2-3
Stentless pericardial AV normal MG
8-9
Stented pericardial AV normal MG
10-15
Stented porcine AV normal MG
10-20
Bileaflet mechanical AV normal MG
5-10-15
Single tilting disc AV normal MG
15-20
Caged ball AV normal MG
20-25
AV prosthetic CW jet rounded
Most likely pathologic obstruction
AV prosthetic CW jet pointed
Normal
Functional obstruction
Regurgitation
Functional AV obstruction
High flow
Pressure recovery
PPM
Acceleration time
Time from onset of flow (just inside opening click) to peak velocity
Pathologic AV prosthetic AT
> 100 ms - pathologic obstruction
AV prosthetic AT <100 ms
Normal
Functional obstruction
Regurgitation
Doppler velocity index (DVI) / DI
LVOT velocity / prosthesis velocity
LVOT VTI / prosthesis VTI
Independent of flow conditions / prosthesis size
AV DI pathologic obstruction
<0.25
AV prosthetic stenosis EOA
LVOT area * LVOT VTI / prosthetic VTI
Normal AV prosthetic EOA
> 1.2
Possible obstruction EOA AV prosthetic
0.8-1.2
Significant stenosis EOA AV prosthetic
<0.8
Indexed EOA (iEOA)
EOA / body surface area
Can differentiate pathologic from functional obstruction
AV pathologic obstruction causes
Thrombus
Pannus
Thrombus + Pannus
Degeneration
AV stenosis and significant regurgitation affects which parameters
Peak velocity and MG more flow dependent
ASE AV stenosis algorithm
Peak velocity > 3 m/s
DVI <0.25, contour round, AT > 100 = pathologic, calculate EOA
DVI < 0.25, contour pointed, AT < 100 = PW doppler sample too far from prosthesis
DVI 0.25-0.29, contour round, AT > 100 = pathologic
DVI 0.25-0.29, contour pointed, AT <100 = normal, check EOA index
DVI >= 0.30, jet pointed, AT < 100 = normal
DVI >=0.30, jet round, AT > 100 = stenosis with sub-valve narrowing, underestimated gradient, improper LVOT velocity (too close to prosthesis)
Location for LVOT diameter
Calipers at insertion between sewing ring and base of septum or anterior mitral leaflet
AV pressure recovery
Pressure / velocity difference between central vena contracta (where echo measures) close to valve and vena contracta further into aortic root (where Cath measures)
More common smaller aortic root, small bileaflet mechanical valve
AV Prosthesis patient mismatch
EOA less than that of normal valve
Determined by indexed EOA
Normal iEOA AV
> 0.85
Moderate mismatch iEOA AV
0.66-0.85
Severe mismatch iEOA AV
<=0.65
AV essential doppler parameters
DI
AT
EOA
iEOA
AV AT > 100 ms
Pathologic obstruction
AV AT <= 100, iEOA <= 0.65
Severe PPM
AV AT <= 100, iEOA > 0.85
Normal
High flow
Pressure recovery
Pathologic regurgitation
MV stented pericardial normal MG
4-7
MV stented porcine normal MG
6-9
MV bileaflet mechanical normal MG
3-6
MV single tilting disc normal MG
4-6
MV caged ball normal MG
7-10
MV E velocity dysfunction
> = 1.9
MV E velocity normal
<1.9
VTI ratio
VTI prosthesis / VTI LVOTI
MV VTI ratio dysfunction
> 2.2
MV VTI ratio normal
<2.2
MV PHT pathologic
> = 130
MV PHT normal, functional, regurgitation
<130
MV significant regurgitation pattern
VTI ratio >2.2
PHT < 130
MV EOA
Do not use PHT
Use continuity equation (area LVOT x VTI LVOT / VTI prosthesis)
Not valid with significant AI or MR
MV EOA Normal
> 2.0
MV EOA possible obstruction
1.0-2.0
MV EOA significant stenosis
<1.0
MV iEOA no PPM
> 1.20
MV iEOA moderate PPM
0.91-1.20
MV iEOA severe PPM
<= 0.90
Pressure recovery phenomenon
Localized pressure drop at the central orifice of a bileaflet mechanical valve is partially recovered distally as flow from lateral two orifices merges with central flow jet
Velocity through prosthetic AV which may prompt concern for pathologic obstruction
<3 m/s
Pressure recovery typically associated with
Small bileaflet mechanical valve
MV most likely to have normal large central jet
Medtronic-Hall single disc valve
Doppler velocity index (DVI)
Subvalvular velocity or VTI / prosthetic velocity or VTI
TV prosthetic stenosis mean gradient
> 6
