The heart in front of Dr. Glen Van Arsdell was a lifeless, white blob, hardly bigger than a tennis ball. It belonged to a 16-day-old infant. The baby had a double outlet right ventricle — a serious heart defect where both arteries arise from the right ventricle.
But Arsdell, the head of cardiovascular surgery at the Hospital for Sick Children, wasn't sweating it. Cracking jokes with a colleague, he kept the atmosphere light as he sewed a patch into the inside of the heart.
"Some people have sports trash talk. Surgeons have surgery trash talk," he said.
There was no real danger here, even if the surgery went wrong. The surgery wasn't real — and neither was the heart. Instead, it was a 3D-printed replica, one of several in the room, meant to be the next-best thing to a real heart for surgeons to practice on.
The faux-surgery was part of a training program at Sick Kids meant to teach new surgeons the literal ins and outs of infant hearts with congenital defects — and teaching them how to fix them, without the need for a real heart.
The program was created by Arsdell and Dr. Shi-Joon Yoo, a cardiac radiologist at Sick Kids. Yoo scans hearts from real infant patients with congenital defects and, with the help of a 3D printer, builds replicas out of material that can be cut, sewn and operated on as if it were the real thing. It's not exactly like human tissue, but it works for training, he said.
"The best available material is what we use now ... my surgeon says it's a little more difficult (the work on the fake hearts) than (the work) he can do on the real patient," Yoo said. "You practice it here, and in the patient, it's easier."
The 3D-printed hearts are a huge development for surgeons who specialize in infant heart defects, Arsdell said. Because of the lack of hearts to practice on — they have to either come from dead donors or animals — most doctors straight out of medical school can wait up to 15 years before getting to even participate in the kind of surgery the surgeons in the room were attempting.
"I trained in the traditional way ... and spent about 10 years getting to where I had the right to operate on children," he said.
With the 3D-printed hearts, surgeons can get a head start on that training without having to worry about the life or death of the patient while they're learning, Arsdell said.
"This is just a much more rapid way of expanding your circle of competence," he said.
Arsdell has other visions for the future of the technology as well. Because each infant heart's condition is so unique — by the time someone makes it to adulthood, their heart conditions tend to be largely the same — 3D printing a heart before a surgery can give a surgeon a few trial runs before attempting it on the real heart. The printing technology isn't there yet, but once it is, Arsdell said he can see it completely changing how he performs some of the most difficult surgeries.
"There are certain types of valves that are enormously complex, and you're in a discovery process in the operating room in terms of how to fit them. I think that's the next step ... we'll print a specific valve, rehearse the operation and come up with a plan we want, and then go to the operating room," he said.
The materials will also improve with time, Yoo said. He envisions a future where scientists can print live cells around a scaffold, which disappears eventually, leaving an actual human heart. The technology is just getting off the ground, but Yoo said in a few years, it will be viable enough for people like him to use.
"We're at the very early stages (with 3D printing), but already it's quite a change from even a year ago," Arsdell said.