NASA designs pump for kids born with half a heart

Washington: NASA scientists have developed a functional prototype of a small conical heart pump to help circulate blood for children born with only one heart ventricle.

By having half a heart essentially, the body is missing half of its pumping ability to oxygenate blood and circulate it to stay alive.

"About 1,500 children are born every year with a missing ventricle. The numbers sound low, but it's actually the fifth most common problem in those with heart issues," said Mark Rodefeld, a paediatric heart surgeon at Indiana University.

Currently, the best solution is a heart transplant, however, it is a limited option due to donor availability and short-term success.

The next best solution, and most commonly used with patients, is a partial fix called the Fontan procedure, which requires three open-heart surgeries to create a passive circulation network to replace the blood pumping function of the missing ventricle.

"The children survive, but eventually, inefficiency in circulation due to the low pumping pressure catches up with them in their early adulthood when the remaining part of the heart gets worn out from doing all the work," Rodefeld said.

Rodefeld came up with an idea to insert a small conical pump, driven by an electrical motor, into an existing Fontan network.

This pump would reproduce the pressures and flow coming from the body and head, reducing the wear and tear on the single remaining ventricle and extend the life of the patient.

"I knew I wanted to put a bi-conical motor into the cross section of the network, but I needed experts in flywheel technology at NASA Glenn to design and scale it to size," Rodefeld said.

Scientists at NASA Glenn Research Centre build a functional prototype of the bi-conical heart pump to allow for traditional motor operation as well as levitation operation.

"Unlike conventional motors, the outside rotor of this pump spins around the inside, which allows for complex fluid pump shapes to be created on the surface of the rotor," said David Avanesian, from NASA.

"Those shapes then 'grab' blood coming from the body and head, mix it, and then direct it to lungs for oxygenation using the von Karman effect for asymmetrical flow pattern," said Avansian.

The team's extensive design, build and testing led to successful results proving the feasibility of Rodefeld's original idea.

While the size of the motor has been scaled down significantly, engineers need to make it even smaller to fit into the Fontan circulation architecture.

Further development would help scale the motor down to the required diameter - the size of a nickel.