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Types of Prosthetic ValvesBIOLOGIC� STENTED
Porcine xenograftPericardial xenograft
� STENTLESSPorcine xenograftPericardial xenograftHomograft (allograft)Autograft
� PERCUTANEOUS
MECHANICALBileafletSingle tilting discCaged-ball
25 different brand names>44 different modelsSizes 17-35 mm
Types of prosthetic valves
� Mechanical vales
� Biologic (tissue) valves
� Percutaneous biologic valves
Diagnostic methods for evaluating
prosthetic valve function
� Echocardiography with Doppler is the modality of choice for anatomic and hemodynamic evaluation of prosthetic heart valves
� Cine fluoroscopy
� Cardiac Catheterization
� Computed Tomography
3-D echocardiography and Doppler
Assessment of the whole valve apparatus and the annulus
MITRAL POSITION > aortic position
Cinefluoroscopy � TEE sensitivity
Mitral position
100%
Aortic position
85%
� CF has a complementary diagnostic role in evaluating disc mobility of mechanical valves in the aortic position
Muratori M, Montorsi P, Teruzzi G, et al: American Journal of Cardiology 2006
Computed Tomography
Tsai I-C, Lin Y-K, Chang Y, et al: Eur Radiol 2009
Pannus formationResidual angle 66 degreesIntra-operative findings
Common “physiologic” characteristics of
prosthetic valves
� Stentless, cadaveric homograft and autograft aortic valves may be indistinguishable from native valves by echocardiographic imaging
Stentless aortic valve 2 years post-op
Native aortic valve
Common “physiologic” characteristics of
prosthetic valves
Acoustic shadowing
� Acoustic shadowing is not a significant limitation of TTE to assess prosthetic aortic valves,
as it is in mitral prosthetic valves
� Acoustic shadowing is more prominent with mechanical valves compared to biologic valves
Shadowing & Flow Masking
Common “physiologic” characteristics of
prosthetic valves
�“Physiologic” stenosis
�“Physiologic” regurgitation
Causes of “physiologic” stenosis
�Valve design / Valve type
�Valve size
�Pressure recovery phenomenon
�Increased flow across the valve
�Patient-prosthesis mismatch
Causes of “Physiologic” regurgitation”
� Backflow from the closing movement of the ball or disc(s)
� Bileaflet and single disc valves have built-in, additional leakage backflow
The purpose of this design is to reduce the risk of valve thrombosis
� Biological valves have minimal or no intrinsic regurgitation at implantation
Daniels CJ, Barbetseas J, Boudoulas H: ACC SAP, version 7, 2009
Early and Late Complications of
Prosthetic Valves� Patient-prosthesis mismatch
� Dehiscence
� Primary failure
� Thrombosis and thromboembolism
� Pannus formation
� Pseudoaneurysm formation
� Endocarditis
� Hemolysis
Distinction between thrombus and pannus
Aortic St Jude Medical valvePannus formation
TRANSESOPHAGEAL ECHOCARDIOGRAPHY
INDICATIONS OF TEE IN PROSTHETIC VALVESINDICATIONS OF TEE IN PROSTHETIC VALVES�� Valvular regurgitationValvular regurgitation
Mitral and tricuspid valves Mitral and tricuspid valves >> aortic valvesaortic valves�� Suspected valve obstructionSuspected valve obstruction
Assessment of valve motion, thrombus vs pannus, Assessment of valve motion, thrombus vs pannus, candidates for thrombolysiscandidates for thrombolysis
�� Evaluation of associated structural abnormalitiesEvaluation of associated structural abnormalitiesVegetations, thrombi, ring abscess, pseudoaneurysm, Vegetations, thrombi, ring abscess, pseudoaneurysm,
fistulasfistulas�� Atrial, atrial appendage thrombiAtrial, atrial appendage thrombi�� Inadequate transthoracic echocardiographic studyInadequate transthoracic echocardiographic study
Barbetseas J & Zoghbi WA: Cardiology Clinics 1998
Parameters in the Comprehensive Evaluation of
Prosthetic Valve Function
CLINICAL INFORMATION
� Date of valve replacement
� Type and size of the prosthetic valve
� Height, weight, body surface area
� Symptoms and related clinical findings
� Blood pressure and heart rate
IMAGING OF THE VALVE
� Motion of leaflets or occluder
� Presence of calcification on the leaflets or abnormal echo densities on the various components of the prosthesis
� Valve sewing ring integrity and motion
DOPPLER ECHOCARDIOGRAPHY OF THE VALVE
� Contour of the jet velocity signal
� Peak velocity and gradient
� Mean pressure gradient
� VTI of the jet
� DVI
� Pressure half-time in MV and TV
� EOA
� Presence, location and severity of regurgitation
OTHER ECHOCARDIOGRAPHIC DATA
� LV and RV size, function, and hypertrophy
� LA and right atrial size
� Concomitant valvular disease
� Estimation of pulmonary artery pressure
PREVIOUS POSTOPERATIVE STUDIES
� Comparison of above parameters is particularly helpful in suspected valvular dysfunction
Normal Prosthetic Valves
DETERMINANTS OF VELOCITY/GRADIENT
� Valve size
� Valve type
� Flow rate
Normal Doppler echocardiographic values
for PrAVs
St Jude St Jude
AorticAortic
Size(mm)Size(mm)Peak VelPeak Vel Mean Mean
GrGrDVIDVI EOAEOA
(ECHO)(ECHO)
EOA EOA
(SR AREA)(SR AREA)
1919
3131
3.03.0±±0.60.6
2.12.1±±0.60.6
1717±±77
1010±±66
0.370.37±±0.070.07
0.490.49±±0.190.190.990.99±±0.200.20
3.083.08±±1.091.09
1.041.04±±0.190.19
3.723.72±±1.401.40
Chafizadeh ER & Zoghbi WA: Circulation 1991
Doppler Echocardiographic Evaluation of
Prosthetic Aortic Valves
DOPPLER ECHOCARDIOGRAPHY OF THE VALVE
� Peak velocity/gradient
� Mean gradient
� Contour of the jet velocity (AT)
� DVI
� EOA
� Presence, location, and severity of regurgitation
PERTINENT CARDIAC CHAMBERS
� LV size, function, and hypertrophy
Normal vs obstructed prosthetic aortic valve
Doppler Parameters of Prosthetic
Aortic Valve Function
SUGGESTS STENOSIS
Peak Velocity > 4 m/s
Mean Gradient > 35 mmHg
DVI < 0.25
EOA < 0.8 cm2
Contour of the jet Rounded, symmetrical
Acceleration Time > 100 ms
Echocardiographic and Doppler Parameters
in Evaluation of Prosthetic Mitral Valve
Function (Stenosis or Regurgitation) DOPPLER ECHOCARDIOGRAPHY OF THE VALVE
Peak early velocityMean gradientHeart rate at the time of DopplerPressure half-timeDVI=VTI PrMV/VTI LVOEOAPresence, location, and severity of regurgitation
OTHER PERTINENT ECHOCARDIOGRAPHIC AND DOPPLER PARAMETERS
LV size and functionLA sizeRV size and functionEstimation of PASP
Prosthetic Mitral Valve
BEFORE AND AFTER THROMBOLYSIS
Doppler Parameters of Prosthetic
Mitral Valve StenosisSUGGESTS SIGNIFICANT STENOSIS
Peak Velocity > 2.5 m/s
Mean Gradient > 10 mmHg
EOA (continuity equation) < 1 cm2
Pressure half-time > 200 ms
Prosthetic Mitral Valve
Limitations of Pressure Half-time Method
� Merging of E and A velocities ( PR, tachycardia)
� Delayed LV relaxation
� Decreased LV compliance
� Atrio-ventricular coupling
� Significant aortic insufficiency
Parameters for Evaluation of the Severity of
Prosthetic Aortic Valve Regurgitation
SEVERE
VALVE STRUCTURE AND MOTIONMechanical or bioprosthetic Abnormal
STUCTURAL PARAMETERSLV size Dilated
DOPPLER PARAMETERS (qualitative or semiquantitative)Jet width in central jets (% LVO diameter): colorJet density: CW DopplerJet deceleration rate (PHT, ms): CW DopplerLVO flow vs pulmonary flow: PW DopplerDiastolic flow reversal in the Desc Ao: PW DopplerDOPPLER PARAMETERS (quantitative)Regurgitant volume (mL/beat)Regurgitant fraction (%)
Large (≥65%)DenseSteep(<200)Greatly increasedProminent, holodiastolic
>60>50
TEEParavalvular significant AR
Transthoracic Echocardiographic Findings
Suggestive of Significant Prosthetic MR in
Mechanical Valves with Normal Pressure Half-time
FINDING COMMENTS
Peak mitral velocity ≥ 1.9 m/s Also consider high flow, PPM
VTI PrMV / VTI LVO ≥ 2.5 Measurement errors increase in AF due to difficulty in matching cardiac cycles; also consider PPM
Mean gradient ≥ 5 mmHg At physiologic heart rate; also consider high flow, PPM
LV stroke volume (2D or 3D imaging) is > 30% higher than systemic stroke volume by Doppler
Validation lacking; significant MR is suspected when LV function is normal or hyperdynamic and VTI LVO is < 16 cm
Maximal TR jet velocity > 3m/s Consider residual postop pulmonary hypertension or other causes
Systolic flow convergence seen in the LV toward the prosthesis
Validation lacking; technically challenging to detect readily
Echocardiographic and Doppler Criteria for Severity
of Prosthetic MR Using Findings from TTE and TEE
SEVERE
STRUCTURAL PARAMETERSLV sizeProsthetic valve
Usually dilatedAbnormal
DOPPLER PARAMETRSColor flow jet area
Flow convergenceJet density: CW DopplerJet contour: CW DopplerPulmonary venous flow
Large central jet (usually > 8 cm2 or > 40% of LA area) or variable size wall-impinging jet swirling in the left atriumLargeDenseEarly peaking, triangularSystolic flow reversal
QUANTITATIVE PARAMETERSVC width (cm)R vol (mL/beat)RF (%)EROA (cm2)
≥ 0.6≥ 60≥ 50≥ 0.50
Imaging and Doppler Parameters in
Evaluation of Prosthetic Pulmonary Valve
Function
DOPPLER ECHOCARDIOGRAPHY OF THE VALVE
� Peak velocity/peak gradient
� Mean gradient
� DVI, EOA (few data exist)
� Presence, location, and severity of regurgitation
RELATED CARDIAC CHAMBERS
� RV size, function, hypertrophy, and RV systolic pressure
Findings Suspicious for Prosthetic
Pulmonary Valve Stenosis
� Cusp or leaflet thickening or immobility
� Narrowing of forward color map
� Peak velocity through the prosthesis >3 m/s or 2 m/s through a homograft (suspicious but not diagnostic of stenosis)
� Increase in peak velocity on serial studies
� Impaired RV function or elevated RV systolic pressure
Evaluation of Severity of Prosthetic
Pulmonary Valve RegurgitationSEVERE
Valve structure Abnormal or valve dehiscence
RV size Dilated (unless there are other reasons)
Jet size by color Doppler (central jets) Usually large, with a wide origin; jet width >50% of pulmonary annulus;may be brief in duration
Jet density by CW Doppler Dense
Jet deceleration rate by CW Doppler Steep deceleration (not specific for severe PR), early termination of diastolic flow
Pulmonary systolic flow vs systemic flow by PW Doppler
Greatly increased (cutoff values are not well validated)
Diastolic flow reversal in the pulmonary artery
Present
Echocardiographic and Doppler Parameters in
Evaluation of Prosthetic Tricuspid Valve Function
DOPPLER ECHOCARDIOGRAPHY OF THE VALVE� Peak early velocity� Mean gradient� Heart rate at time of Doppler assessment � Pressure half-time� VTI PrTV / VTI LVO� EOA� Presence, location, and severity of TRRELATED CARDIAC CHAMBERS, IVC AND HEPATIC
VEINS� RV size and function� Right atrial size� Size of IVC and response to inspiration� Hepatic vein flow pattern
Doppler Paramters of Prosthetic
Tricuspid Valve FunctionCONSIDER VALVE STENOSIS (average ≥5 cycles)
Peak velocity(increased also with TR)
> 1.7 m/s
Mean gradient(increased also with TR)
≥ 6 mm Hg
Pressure half-time ≥ 230 ms
EOA and VTI PrTV/VTI LVO No data yet available for tricuspid prosthesis
Echocardiographic and Doppler Parameters Used
in Grading Severity of Prosthetic Tricuspid Valve
Regurgitation
SEVERE
Valve structure Abnormal or valve dehiscence
Jet area by color Doppler,central jets only (cm2)
> 10
VC width (cm)(for valvular TR jet, extrapolated from native TR, unknown cutoffs for paravalvular TR)
> 0.7
Jet density and contour by CW Doppler Dense with early peaking
Doppler systolic hepatic flow Holosystolic reversal
Right atrium, right ventricle, IVC Markedly dilated
Comprehensive Evaluation of
Prosthetic Valve Function
� Clinical evaluation, know valve type and size
� Baseline echo/Doppler study after surgery
� Transthoracic 2D/Doppler evaluation of structure and function is the first line diagnostic method
� In cases with high velocity jet/gradient and suspected stenosis or regurgitation:
- Compare with previous studies
- TEE, fluoroscopy (if needed for aortic
mechanical prosthetic valve), CT (?)
THANK
YOU
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