Dr. Alex Starr was a young surgeon at the University of Oregon Medical School in 1957. One day he was visited by M. Lowell Edwards, an old engineer who wanted help in creating the artificial heart. Starr, knowing medical science was no where near that kind of technology, proposed that they try just making an artificial mitral valve first .
At first they tried using Dacron cloth between layers of Teflon with Silastic mounted across it and proceeded to test them on dogs. As this was after the creation of the cardiopulmonary bypass machine they could open the animals up and replace the actual mitral valve and insert the prosthetic. Unfortunately the dogs did not survive due to thrombotic occlusion or the blockage of a blood clot in the vascular artery . Starr and Edwards redesigned their model based on the Hufnagel design but this time opening up the Hufnagel tube and using a quieter ball made of Silastic. This yielded positive results until all but one of the test dogs started dying due to the thrombosis problem. Then, Starr had his Eureka! moment. One day as he was walking around the school’s campus he watched as cherry blossoms were blooming in the trees. Then it occurred to him: why not use a stainless steel frame and a better sewing ring . How this relates to cherry blossoms is unclear but the team soon saw an “80% long-term animal survival with no thrombosis” .
The first implantation on a human occured in August 1960 on a 40 year old woman with congestive heart failure, ending in the patient suddenly dying of an air embolism  which is the sudden blocking of the veins due to air bubbles entering the blood stream during surgery . The embolism was not due to the valve but the implantation procedures so the second surgery on a man named Ralph Berg, however, was a complete success. 
Edwards created a company, Edwards Laboratories to manufacture the valves in which Starr held no financial interest in order to create “no conflict of interest” . The company turned into Edwards Lifesciences Inc. in California which has gone on to create other “medical innovations, including the Swan-Ganz catheter, the first technology ever used for hemodynamic monitoring of critically ill patients, and the Fogarty line of embolectomy catheters, the first catheter-based technologies used to remove blood clots from the arms and legs” . Edwards was awarded the American Medical Association’s Layman’s Citation for Distinguished Service and died in 1982 .
Albert Starr is still practicing medicine and is currently at the Providence Heart and Vascular Institute based at St. Vincent Medical Center. He studied under Alfred Blalock at Johns Hopkins starting in 1945 and in 1963 “performed the world’s first successful triple-valve replacement” and Oregon’s first heart transplant in 1985 .
Positioning of the Valve:
As you can see in the picture [source] the Mitral valve on the left side of the heart is where the first Starr-Edwards valves were implanted.
Video [not graphic or gross]:
[kml_flashembed movie="http://www.youtube.com/v/G5S0yQhK42s" width="425" height="350" wmode="transparent" /]