1. Valve Replacement Mechanical versus Biological
Prof. Dr. T. Carrel
Swiss Cardiovascular Center
University Hospital Berne
Switzerland
No Disclosure

2. Agenda The Institutional Experience The Market (Current Estimations)
The ESC and ACC/AHA Guidelines
The Decision-Making Process
The Literature: Pro and Cons
The Future

3. The Institutional Experience
768
400
185
Ross ≈10/yr
David ≈20-30/yr
Swiss Cardiovascular Center University Hospital Berne, Switzerland

4. The Institutional Experience
Increasing Number of Patients with AVR
Absolute number of mechanical AVR remains stable
(3) Relative number of mechanical AVR decreased
New generation of tissue valves have a lower rate of SVD
Life-style changes (QoL without warfarin)
Changes in Guidelines and Literature regarding cut-off age

5. The Current (surgical) Market
(≈ 200‘000 pts per year)
78-85%
15-22%
(43% in 1997)
(55% in 1997)

6. The Future (global) Market
(≈ 500‘ ‘000‘000 pts per year)
> 50%

7. The ESC/EACTS Guidelines

8. The AHA/ACC Guidelines
Nishimura RA, AHA/ACC Guidelines
Circulation 2015

9. The Decision-Making Process
Objective Criterias
Durability of the Device
Need for Anticoagulation
Risk of Prosthetic Endocarditis
Life expectancy of the Patient
Quality of Life
Subjective Criterias
Patient’s opinion
Cardiologist’s Recommendation
Institutional Strategy
Recommendations through others
(online, relatives, patients)

10. The Decision-Making Process
Arguments that may influence valve selection
New anticoagulation strategies
New valve design
pro mechanical valve
Valve-in-valve concept with TAVI
pro tissue valve
Individual Confort vs Economic Burden

11. The Patient‘s Perspective
„Patients who need heart valve replacement come with the anticipation of receiving, according to their conditions, the most appropriate valve substitute for the rest of their life. They hope to be operated on only once and to be free of complications
K. Arom, J Heart Valve Dis 1996;5:505-10

12. The Patient‘s Perspective
“Consensus guidelines have increasingly emphasized patient preference in preoperative decision making. Quality-of-life surveys indicate that many patients view the distant possibility of reoperation as a reasonable trade-off for freedom from lifelong anticoagulation, reduced quality of life, and poorer perceived health status associated with mechanical prosthetic valves“.
Chikwe J et al. JAMA, April 14, 2015

13. The Patient‘s Perspective
Mechanical Valves
Freedom from Reoperation but Anticoagulation
Tissue Valves
Freedom from Anticoagulation but Reoperation

14. The Literature: Historical
Suri R, Circulation 2013;128:1372

15. The Literature: Historical

16. The Literature: Historical

17. The Literature: Historical
Actuarial: freedom from SVD - assumes all patients are alive
Actual: death competes to reduce the likelihood of reoperation

18. The Literature: Historical
Old type of tilting-disk prosthesis
Biological design no more available
Results not stratified by age groups
Perioperative mortality was higher

19. The Literature: Pro and Cons
Circulation 2013;128:

20. The Literature: Pro Mechanical
Suri R, Circulation 2013;128:1372

21. The Literature: Pro mechanical
Freedom from bleeding
Overall survival
220 pts, matched for age, gender, CABG and valve size
SJM vs CE
Brown M, J Thorac Cardiovasc Surg 2008;135:878-84

22. The Literature: Pro Mechanical
Reoperation according to age at implantation
3975 pts (3152 AVR) with first time tissue valve
75% redos in pts !
Chan V et al. Circulation 2011;124 Suppl1:S75-80

23. The Literature: Pro Mechanical
345 pts > 80 years
58% tissue vs 42% mechanical
Follow-up 40±33 months
Overall survival benefit in pts with mechanical valves
No influence on QoL
Ann Thorac Surg 2008;85:

24. The Future Avoid Unpredictable SVD
- negative effects of adverse cumulative hemodynamics
- ViV-TAVI is less than optimal and expensive
Mitral CE and Aortic Trifecta 3 yrs after AVR+MVR

25. The Future
Hope for a MEC valve w/o AC
(Triflo Medical Switzerland)

26. The Future
No inherent difference in material thrombogenicity between mechanical and tissue valves
Material factor is NOT a reason for the poorer performance of CARBON valve
Thrombogenicity of prosthetic heart valves is design-related
Didier Lapeyre, M.D.

27. Biomolecular Link between Fluid Forces and Platelet Aggregation
The Future a
New Methodologies to Test Mechanical Prostheses
Biomolecular Link between Fluid Forces
and Platelet Aggregation
Projected Dynamic Valve Area (PDVA)
Digital Particle Imaging Velocimetry (DPIV)
Parallel Computational Platforms (CFD)
Platelet-Shear Flow Interactions (PSFI)
Didier Lapeyre, M.D.

28. Closure starts after Onset of Reversed Flow
close earlier and more smoothly
abrupt closing
Didier Lapeyre, M.D.

29. Unadressed Extreme Closing Volume Velocity
- Cavitation
- Micro-bubbles formation (HITS)
- Vortex Formation
Didier Lapeyre, M.D.

30. A mechanical valve w/o anticoagulation
The Future
A mechanical valve w/o anticoagulation
Physiologic hemodynamic profile
No “jet-like” flow regions
No “hot spots” in the pivoting spaces
Leakage flow velocity 1 m/s
Warfarin-free
Not prone to structural failure
Didier Lapeyre, M.D.

31. The Future: „Predictions“
AVR Surgery must be „re-designed“
- Small incision
- Miniaturized CPB
- Single shot „low volume“ cardioplegia
- Valve device with unlimited durability
Pts with Life Expectancy > yrs
- MECHANICAL prosthesis w/o AC
All others Pts: TA - or TF-TAVI