Constantly flowing artificial heart has no heartbeat or pulse…
Scientists at the Texas Heart Institute have developed a new artificial heart that does not pump blood around the body to rhythmic beat of a pulse; instead it employs spinning motors to provide a constant, streaming of flowing blood.
Dr. Billy Cohn and Dr. Bud Frazier devised the artificial heart using medical implants known as ventricular assist devices. These devices aid blood flow by constantly propelling blood in a continuous flow. Many people have these implants, including former Vice President Dick Cheney, but only ever one. What Cohn and Bud did however, is used two of these devices to replace both left and right ventricles, effectively replacing the whole heart.
Artificial Heart Without A Pulse
The spinning mechanism of the device pumps blood constantly, which means there is no heartbeat. Traditional beating artificial hearts have been known to wear out, breakdown and cause blood clots or infections, but Cohn and Bud claim that their simple twin rotor device will outlast any other design.
The new artificial heart was tested on an 8-month-old calf named Abigail at the institute’s animal research laboratory.
Image Credit: Texas Heart Institute, 2011.
After having successfully implanted the device, the pair decided to step up tests to trails in humans.
In March earlier this year Cohn and Bud found their subject, Craig Lewis, a 55year-old technician who worked on Houston’s vast wastewater pumps. Lewis was dying from amyloidosis – which causes the buildup of abnormal proteins – and had been given less than a day to live when they decided to conduct the operation.
The operation itself was a success, but heart surgery alone could not save him. Shortly after awaking from the surgery he began to fade as a result of the amyloidosis attacking his liver and kidneys; however the artificial heart did extend his live for a month.
Lewis’ wife Linda said:
“We knew if it wasn’t a success for Craig, if they could get data that would help them, if it helps the next person, then you did good.”
While a heart that doesn’t beat goes against every living thing in nature, Cohn points out that the only reason blood must be pumped rhythmically instead of continuously is because the heart can only get nourishment in between heartbeats, but “If you remove that from the system, none of the other organs seem to care much.”
The device is still a long way from being commercially available. First the team needs to finalize a design, find a manufacturer and then set upon attaining FDA approval.
Despite the long road ahead, Cohn and Bud are confident their design will make the cut, “these pumps don’t wear out,” added Cohn. “We haven’t pumped one to failure to date.”
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