1. Division of Cardiology Department of Internal Medicine Tae Kyung Yu
PROSTHETIC VALVES
Division of Cardiology
Department of Internal Medicine
Tae Kyung Yu

2. Prosthetic Valves Valve replacement for severe valvular heart diasese
Evaluate prosthetic valve dysfuction
in patients with cardiovascular symptoms

3. Prosthetic Valves Classification Tissue valve
Animal(bioprosthesis or heterograft)
Human(homograft or allograft)
Mechanical valve
St. jude(disk), Starr-Edwards(ball)
Additional prosthetic sounds
Ball movement or disc closure

4. 2-D Echo Gross structural abnormalities
Dehiscence, vegetation, thrombus, degeneration
Limitation
Echo reflectance, attenuation of the ultrasound beam, Reverberation artifact

5. Color Doppler Imaging Flow velocity across a prosthetic valve
Higher flow velocity <- inherently stenotic
Vary according to the type, size, location, CO
Baseline doppler study in the early postoperative period !
Pressure gradient = 4 x Velocity2
potential difference between doppler-derived & catheter-derived prosthetic pr. Gradients

8. Color Doppler Imaging Functional orifice area Continuity equation
DDx regurgitation vs obstruction

10. Interpretation of Increased Prosthetic Flow Velocity
Mitral prosthesis
PHT
LVOT velocity
Obstruction ↑ ↔↓
Regurgitation ↓
Aortic prosthesis
Mitral inflow
LVOT/AV TVI ratio ↔
↔,↓
↔, ↓

11. Obstruction
0.1~0.4%/yr
Depend on valve size, type, location, adequacy of anticoaguation
MMP by thrombus
AMP by pannus formation
Abnormal motion by 2-D echo, TEE
Maximal jet velocity, maximal & mean pr. Gradients, effective area by doppler velocity tracing

12. PPM(Prosthesis-Patients mismatch)
EOA(effective orifice area) of the aortic prosthesis smaller than normal native valve
Common, usually asymptomatic
Moderate(≤0.85 cm2/m2), severe(≤ 0.60cm2/m2) EOA
-> ↑ Mortality
Prevention -> EOA ≥ BSA x 0.85 cm2

13. Calculation of Effective Prosthetic Orifice Area
Continuity equation is a better methods for determining the area of mitral and aortic prosthesis(no significant AR or MR)
MP(or AP) area = LVOT area x LVOT TVI / MP (or AP) TVI
= LVOT diameter( or SROD)2 x x LVOT TVI / MP(or AP) TVI
Stenotic mitral valve area can also be calculated by PISA(proximal isovelocity surface area) method

14. Thrombolytic therapy for obstruction of prosthetic valves
90% by thrombus
48~92% by inadequate anticoagulation
Treatment
Thrombolysis : thrombus ≤ 5mm by TEE
Surgery : clinical condition, functional statue, valve location, comorbid status

15. Regurgitation Color doppler is principal
Limitation with prosthetic valves
Marked attenuation of the ultrasound beam, rebeverbations
PW & CW, TEE

16. Normal prosthetic regurgitant flow
Characteristic flow pattern according to valves

17. Pathologic prosthetic regurgitation

18. TEE Motion of the prosthetic valve MR, TR, AR from post aspect
Dehiscence, endocarditis, ring abscess, intracardiac mass or thrombi

19. Hemolysis after MV Repair or Replacement
Uncommon, but alarming complication
Collision of MR jet against a cardiac structure(m/c), Fragmentation, etc
Develop postoperatively
Anemia, reticulocyte ↓, LDH ↑, haptoglobulin ↓, hemosiderin in urine