There are three basic replacement valves
currently in use, two of them man made. The man made valves are durable but
encourage the formation of blood clots and therefore require the patient to
undergo anticoagulant drug therapy. The biological valve (pig valve) is not
as durable, but it does not require the use of anticoagulants.
Starr-Edwards
 |
 |
|
Open
|
Closed
|
The
Starr-Edwards valve consists of simply a ball and cage. The ball moves up and
down in the cage to open and close the valve.
Bjork-Shiley
 |
 |
|
Open
|
Closed
|
The
Bjork-Shiley valve consists of a disk which tilts to open and close.
Pig
Valve
Pigs
have the same size hearts as humans therefore the valves taken from a pig can
be implanted directly into the heart of a human. The valve then functions in
the same natural method which it did in the pig.
