Prosthetic Valves

Question 1

When are prosthetic valves implanted?

Answer 1

When the patient has hemodynamically significant valvular disease:

- regurgitation
- stenosis
- severe AI/aortic dissection

Question 2

3 pros of mechanical valves?

Answer 2

• durable/long lasting
• risk for failure is low
• easier to implant

Question 3

3 cons of mechanical valves?

Answer 3

• risk of thrombus
• need to be on anticoagulation for life
• pannus growth
• valve may make an audible click sound

Question 4

Bjork-Shiley & Hall-Medtronic valves

Answer 4

Single tilting disk

Question 5

Flow pattern of single tilting disk

Answer 5

Eccentric

Question 6

Most common mechanical valve

Answer 6

Bileaflet tilting disk (St Jude)

Question 7

Colour doppler of this mechanical valve demonstrates 3 jets. Central flow with peripheral turbulence to “wash” the valve

Answer 7

Bileaflet tilting disk (St Jude)

Question 8

Graft of tissue from one site to another in the same patient. Rare

Answer 8

Autograft

Question 9

Graft from one human to another. Rare

Answer 9

Homograft

Question 10

Graft from a different species. Most common

Answer 10

Heterograft/xenograft

Question 11

Pros/cons of bioprosthetic valves

Answer 11

Pros: anticoagulation not required, no valve noises
Cons: not as long lasting, prone to calcification

Question 12

AV replacement - autograft & homograft

• patient’s PV & root become new AV & root
• Donor PV & root implanted

Answer 12

Ross procedure

Question 13

Valve repair that treats regurgitation by restoring the size and shape of normal valvular annulus & prevents recurrent dilation

Answer 13

Annuloplasty ring

Question 14

Balloon valvuloplasty is often required prior to this.

Answer 14

TAVR (transcatheter AV replacement)

Question 15

double orifice MV, used to treat MR

Answer 15

MitraClip (edge to edge repair)

Question 16

4 types of valve dysfunction:

Answer 16

1. Structural failure
2. Regurgitation
3. Thromboembolic complications
4. Endocarditis

Question 17

What are the 2 most frequently used Doppler parameters when assessing prosthetic valve stenosis?

Answer 17

DVI (Doppler velocity index) and the EOA (effective orifice area)

Question 18

Thrombus vs. Pannus

Answer 18

Thrombus: mobile, occurs shortly after implantation, can be quite large, requires medication, usually MV
Pannus: fixed, occurs over time, fibrous/scar tissue, most common on AV

Question 19

What type of bioprosthetic valve would a porcine valve be considered?

Answer 19

Heterograft

Question 20

What are normal DVI and EOA values? (Generally)

Answer 20

DVI = >/= 0.3
EOA = >1.0