By Alethea Drexler
The Thingamajig returns! I didn’t intend to get this far behind, but it’s past time to get back on track and dig some more curiosities out of the archives.
Today’s Thingamajig is an artificial heart valve, from the medical instruments collection. This one was given to us by Dr. Don Chapman, and was accompanied by three small pacemakers. I included the quarter for scale (I picked Nevada because it’s one of the most picturesque of the state quarters. I was a horse-crazy little girl).
There are several different types of artificial heart valve. Other types include one with a rotating disk, and several variations of ball valves, which operate a little like the tip of a ballpoint pen. This one is called a “bileaflet” valve because it has two semicircular flaps. A good article with pictures of the other types was published by The Annals of Thoracic Surgery in “Mechanical Heart Valves: 50 Years of Evolution.”
The valve is closed in the top picture; the break between the dark and lit areas indicates where the two leaflets separate. The lower picture shows the valve with the leaflets open.