Prosthetic valves for final

  1. Image Upload 1

    What type of valve?
    Mechanical 

    Ball and Cage or Caged Ball
  2. Image Upload 2
    Caged Disk (low profile) – used in the 1970’s. Similar to caged ball valves but disk enclosed in cage and attached to fabric covered sewing ring. Blood flow would go around disk so it produced high velocities and therefore high pressures.  Blood turbulence and cell damage were problems.  Not currently used.

    Example:  Beal-Surgitool, Kay-Suzuki
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    • Tilting Disk or the “toilet seat” valve – a single disk that creates a large opening and a small opening. Also low profile. High pressure gradients, high thromboembolic complications.  Used in 1970’s and 80’s.
    • Examples:

    –Medtronic Hall Omnicarbon, Monostrut, and Bjork-Shiley (discontinued)
  4. Image Upload 4
    • Bileaflet Tilting Disk – Two tilting disks create three orifices and promote central flow through valve. That is the key in recognizing it by echo. Least stenotic. Low profile.
    • Examples:
    • –St. Jude – most common in US
    • –CarboMedics
    • –ATS Open Pivot
    • –Conform-X
  5. 8 Complications of Mechanical Prosthetic Valves
    • 1. They are more stenotic than tissue valves.
    • 2. Risk of “pannus” or fibrous ingrowth of tissue that may lead to stenosis or regurgitation.
    • 3.Perivalvular leaks – all mechanical valves leak a little.
    • 4. Dehiscence can cause perivalvular leaks
    • 5. Ring abscess
    • 6. Infective endocarditis
    • 7. Mechanical failure
    • 8. Hemolysis – damage red blood cells as they pass through valve.

    Advantage: They last a long time!
  6. Mechanical valves in the mitral position have an M-mode that resembles what other valve's m-mode?
    Mechanical valves in the mitral position have an M-mode that resembles a box, just like the native aortic valve.
  7. True or False
    Bioprosthetic MV spectral Doppler tracings are similar to native valve. Flow is fairly laminar with a small amount of regurgitation.
    True
  8. What valve is possible to confuse with calcification?
    the Carpentier ring
  9. A flexible ring that is sewn into the annulus to decrease the amount of opening and thus regurgitation.  It is considered a repair instead of replacement.
    The Carpentier ring
  10. equation used to estimate the area of a mechanical prosthesis
    MVA continuity equation

    • MVA=.785 (LVOT diameter squared)(LVOT VTI)
    •                           MV VTI
  11. bioprosthetic MVA using what equation
    P 1/2T 

    • MVA= 220
    •         P1/2T
  12. What gradient is important to look at on mitral valve?
    the mean gradient
  13. Mitral valve should be replaced when vlalve area is ___ cm squared or less and/or MR of such severity it leads to ____ failure or the patient is _____.
    1.0 cm 

    LV failure

    Symptomatic
  14. Aortic valve should be replaced if it is:
    *___ cm squared or less
    *has a mean gradient of ___ mmHg
    *progressive LVH
    *LVESd of ___mm or 5.5 cm
    • *.5cm squared or less
    • *50 mmHg
    • *LVESd of 55mm or 5.5cm
  15. All prosthetic valves are to some degree ____.
    stenotic

    have higher then normal velocities
  16. 2 types of valves that can be implanted:
    • Synthetic or mechanical valves
    • Bioprosthetic or tissue valves
  17. which valve does the patient have to be on a blood thinner for the rest of their life?
    Synthetic or mechanical valves
  18. Which valve would last the longest?

    mechanical or tissue
    Mechanical
  19. Which of these two types would be more stenotic?
    Mechanical
  20. How does the physician decide which valve to use?
    • *Patient age
    • *Medical history
  21. The older the patient, the more likely they will be to have a ______ valve.

    bioprosthetic or synthetic?
    bioprosthetic/tissue valve
  22. M-mode for a MV prosthetic valve:
    Image Upload 5
  23. Types of Bioprosthetic valves
    • 1. Autograft
    • 2. Homograft
    • 3. Allograft
    • 4. Heterograft or Xenograft
  24. graft of tissue from one site to another-same individual. Self to self. No problems with rejection.
    Examples:

    –Ross procedure, CABG, skin grafts, fascia lata (thigh muscle covering is prepared and used as a heart valve)
    Autograft
  25. graft from one individual to another of same species. Genetic makeup must be the same.
    Example:

    –Identical twins – harvested from deceased, kidneys are harvested from family members.

    –Dura mater (from brain covering) can be prepared and used as heart valve.
    Homograft
  26. The transplant of an organ or tissue from one individual to another of the same species with a different genotype. A transplant from one person to another, as in heart transplant.
    Allograft
  27. graft from one individual to another of different species.
    Examples:

    –Porcine (pig) valve to aortic

    –Bovine (cow) pericardium mounted on stents and sewing ring

    –Common brands include:  Carpentier-Edwards, Medtronic, Hancock, Ionescu-Shily (discontinued), Edwards Prima Plus, Toronto SPV
    Advantages: laminar flow, resembling native valve, lower incidence of thromboembolism.
    Disadvantages: last 10-12 years
    Heterograft or Xenograft
  28. complications of bioprosthetic valves
    • Calcification and degeneration with age.
    • Thrombus
    • Infective endocarditis
    • Perivalvular leaks – regurgitation around the sewing ring.
    • Dehiscence – sutures becoming loose or break causing rocking and perivalvular leaks
    • Risk of ring abscess
    • Plus they don’t last as long!
  29. What does TAVR stand for?
    Trans-aortic valve replacement procedure
Author
Anonymous
ID
330914
Card Set
Prosthetic valves for final
Description
pictures and descriptions
Updated