choosing between a prosthetic valve and a biological valve
Last reviewed 01/2018
- the major advantage of mechanical over biological valves is their very low
rate of failure. Their main disadvantage is thrombus formation
- the major advantage of biological over mechanical valves is that long term
anticoagulation is not needed. Their major disadvantage is the risk of structural
deterioration over time because of leaflet degeneration and dystrophic calcifiication
both of which are relatied to the position (mitral > aortic) and the patient
age
- "..The increasing confidence in bioprostheses, coupled with the increasing
age of the patient population, is reflected in the increasing proportion of
bioprosthetic valves, particularly pericardial valves, and the decreasing
proportion of mechanical prostheses being implanted..."
- risk of thromboembolism is on average 0.7% per year in patients with biological
valves in sinus rhythm. Among patients > 65 years old undergoing primary
aortic valve replacement (AVR) fewer than 10% of biological valves with require
replacement for stutural valve deterioration over a 15 year period
- a biological valve is the only option for patients who cannot take oral anticoagulants such as a young women planning to become pregnant
Reference:
- 1) BHF (factfile May 2009). Prosthetic heart valve.