The first mechanical heart valve was implanted in 1952. This first valve was a ball valve and it was designed by Dr. Charles Hufnagel. This valve was implanted in a 30-year-old woman who could lead a normal life after the surgery.
The downside to this design was that it could only be placed in the descending aorta instead of the heart itself. For this reason it did not fully correct the valve problem, only alleviate the symptoms. However it was a significant achievement because it proved that synthetic materials could be used to create heart valves.
In 1960, a new type of valve was successfully implanted: the Starr-Edwards ball valve. This valve was a modification of Hufnagel’s original valve. The ball of the valve was slightly smaller and caged from both sides so it could be inserted into the heart itself.
Tilting discs were introduced in the later 1960s. These valves were a great improvement over the ball designs. They allowed blood to flow in a more natural way while reducing damage to blood cells from mechanical forces. Unfortunately, the struts of these valves tended to fracture from fatigue over time.
Bileaflet valves were introduced in 1979. Blood flows directly through the center of these valves (like in an intact heart valve) which makes these valves superior to other designs. The major drawback of this design is that it allows some backflow. A vast majority of mechanical heart valves used today have this design. |
