Prosthetic Heart Valves

Question 1

How may prosthetic HV present to hospital

Answer 1

Hear failure
Bleeding (anticoag)
Endocarditis
Haemolysis
Dysfunction of valve

Question 2

When do you hear a prosthetic HV?

Answer 2

On closure

Question 3

When may you find O/E when patients with a prosthetic HV?

Answer 3

audible click (mechanical only)
signs of IE
Jaundice due to haemolysis
Anaemia
Bruising due to anticoag
Scars (midline sternotomy)

Question 4

Is it normal to hear a murmur with prosthetic valves?

Answer 4

a soft systolic murmur for pulmonary and aortic valves. can sometimes be heard. Valves are also designs to permit trace amounts of regurg to present thrombus formation. However, audible regurg is always abnormal may mean paravalvular leak. If muffled clicks may be clot on valve.

Question 5

Do allograph (tissue) prosthetic valves require anticoagulation?

Answer 5

Typically no, only in the short term (3 months). Varying anticoagulation is used (sometimes aspirin, other times warfarin). stopped after endothelisation.

Question 6

What may you hear don auscultation of tissue valve

Answer 6

Not alot - heart sound may be more ‘dull’

Question 7

Pros of mechanical valves

Answer 7

More durable and last longer (ideal if <60). Means less chance of repeat operation. useful if patient already has AF

Question 8

Cons of mechanical valves

Answer 8

Anticoagulation life long and its consequences. higher thromboembolic risk

Question 9

INR for aortic and mitral mechanical valve replacement

Answer 9

AVR 2-3
MVR 2.5-3.5

Question 10

Pros of tissue (bioprosthetic) valves

Answer 10

No need for long term anticoagulation

Question 11

Cons of tissue (bioprosthetic) valves

Answer 11

High degeneration therefore may need reoperation. require more FU. AV degen quicker than MV, might be more suitable in elderly.

Question 12

Complication of valve replacement

Answer 12

Thromboembolic events
Bleeding
Valve dysfunc (bios last 10 years or so)
Haemolysis
IE
AF
PPM insertion (esp aortic)

Question 13

What are some considerations for surgery for patients with bileaflet aortic valves (no AF/ no thromboembli, no LVD) on warfarin

Answer 13

Omit 72hours pre op. restart 24 hours later no herparin cover

Question 14

What are some considerations for surgery for patients who do not have a bileaflet aortic valves (no AF/ no thromboembli, no LVD) on warfarin

Answer 14

Omit warfarin 48hr before, IV heparin when INR<2. stop 4-6 hours pre op. Restart warfarin as soon as feasibly possible until INR >2.5