After decades of trial and error among surgeons desperately trying to create a machine that wouldn’t break down or cause blood clots and infections, two doctors at the Texas Heart Institute developed a device that used whirling rotors to pump blood around the body without a heartbeat. 

Dr. Billy Cohn and Dr. Buz Frazier first tested the idea in an eight-month-old calf called Abigail, removing her heart and successfully replacing it with two centrifugal pumps, which circulated the blood through her. 

“By every metric, we have to analyze patients, she’s not living,” Cohn told NPR. 

“But here you can see she’s a vigorous, happy, playful calf licking my hand.” 

After practicing on 38 calves, Cohn and Frazier progressed to human trials – selecting a 55-year-old man called Craig Lewis, who was suffering from amyloidosis, a rare autoimmune disease that causes a build-up of abnormal proteins and, in turn, rapid heart, kidney, and liver failure. 

Lewis’ heart had become so damaged that doctors gave him about 12 hours to live, at which point his wife Linda suggested something drastic. 

His wife Linda said: “He wanted to live, and we didn’t want to lose him. “You never know how much time you have, but it was worth it.”