In 1981, William DeVries submitted a request to the FDA for permission to implant the Jarvik 7 into a human being. On 2 December 1982, Kolff implanted the Jarvik 7 artificial heart into Barney Clark, a dentist from Seattle who was suffering from severe congestive heart failure. Clark lived for 112 days tethered to an external pneumatic compressor, a device weighing some , but during that time he suffered prolonged periods of confusion and a number of instances of bleeding, and asked several times to be allowed to die.