It may sound like something out of science fiction, but doctors at Children’s National Medical Center in Washington, D.C., are making hearts. Not actual hearts, but three-dimensional synthetic models churned out by what looks like an ordinary printer.
The only one of its kind at a Washington area hospital, the printer uses data from individual patients to replicate the organs of those individuals, reflecting their particular intricacies and deformities. The device synthesizes images from CT scans or ultrasounds, translating that information into thin layers of plastic that are stacked until they form a three-dimensional object.
The technology, pediatric cardiologist Laura Olivieri said, “is amazing.”
Olivieri said that holding the replica of a heart enables her to make connections that she could not when looking at the actual organ on a computer screen.
“Because you’ve got a three-dimensional problem,” she said. “What we’re all trying to do is reconstruct how far away X and Y are. But now you can just take (the model), and hold it, and look at it, and say, ‘Oh, they’re that far away.’”
In one recent case, Olivieri used a 3-D printer-produced model that she could take apart before the patient’s surgery.
“The cardiac anatomy of this patient is very rare,” said Olivieri. “And it’s not like there’s an FDA-designed device that will solve it.” The model allowed her to “look at the anatomy in 3-D and do some practice runs where the patient isn’t involved.”
To help prep a surgeon who needed to close the hole in an infant’s heart, Axel Krieger, a biomedical robotic expert at the center’s Sheikh Zayed Institute for Pediatric Surgical Innovation, created a model that used a mix of hard and soft plastics so the replica would feel like a real heart.
“We found the perfect combination of materials that actually allows you to place a suture through it or stick a needle through it,” Krieger said. “It feels similar to tissue. You can make a valve soft but the surrounding tissue hard, and then the bone really hard. So you can have different levels of the mechanical properties.”
Children’s hopes to use the printer to create models for patients with rare or complicated conditions, and for those who need corrective procedures on complex congenital defects.
“Congenital heart disease is so structural,” Olivieri said. “On some level, you can predict what a physiology is by looking at [a patient’s] anatomy. So a picture can predict how sick or how well a patient can be. That makes congenital heart disease one of the perfect applications for 3-D printing.”
Though the possibilities of 3-D printing are enormous, the technology is still new, and it’s expensive. The printer at Children’s cost about $250,000. A high-end ultrasound machine can cost about $270,000, and a portable CT unit is about $550,000, according to Laurie Hogan, the director of radiology services at Children’s.
Making 3-D models is also time-consuming. Just prepping ultrasound images for the printer can take many hours.
“The very first one I did was not even recognizable as a heart, and it probably took me like 25 hours to do,” Olivieri said.
But doctors at Children’s believe the investment is worth it.
“Complex congenital heart disease, thank goodness, is fairly rare,” Olivieri said. But “this is something that’s going to really help us take care of them.”