Children’s Hospital of Wisconsin uses live 3-D surgery to teach medical experts about extremely rare heart defect
By Evan Solochek, Children’s Hospital of Wisconsin writer
In a dimly lit auditorium on the second floor of Children’s Hospital of Wisconsin, a group of some of the world’s greatest medical minds gathered together watching an open-heart surgery live in 3-D.
Projected onto an 18-foot screen, the chest cavity felt like staring into some prehistoric cave, the heart a snarling, heaving bear surrounded by arteries and veins the size of tree trunks.
One attendee described the narration echoing throughout the theater as the voice of God.
In reality, the heart being operated on was no bigger than a golf ball, belonging to a 9-month-old boy from Wisconsin with congenitally corrected transposition of the great arteries (CC-TGA). And the voice was of Viktor Hraska, MD, skillfully performing the surgery in an operating room one floor above.
In the world of rare and complex heart defects, CC-TGA is among the rarest and most complex. It’s so rare, in fact, that Dr. Hraska, medical director of pediatric cardiothoracic surgery at Children’s Hospital of Wisconsin, surgical director of the Herma Heart Institute and one of the world’s foremost experts on the topic, only sees two or three cases each year.
“Roughly 1 in 100 babies are born with some form of heart defect, ranging from mild to severe. Of those babies, less than 1 percent will have congenitally corrected transposition of the great arteries,” said Jeanne James, MD, medical director of pediatric cardiology, Children’s Hospital of Wisconsin. “We’re looking at approximately 1 in 20,000 live births. It’s extremely rare.”
In a normal heart, there are four chambers: two atria and two ventricles. The right atrium receives deoxygenated (blue) blood from the body, passes it to the right ventricle that pumps it through the pulmonary artery to the lungs where it becomes enriched with oxygen. The left atrium receives this oxygenated (red) blood from the lungs, passes it to the left ventricle where it is pumped to the aorta and throughout the body. The blue blood then returns to the right atrium and the cycle continues.
In a heart with CC-TGA, the left and right ventricles are on the “wrong” side of the body. The result is the less muscular right ventricle becomes responsible for pumping red blood to the aorta and then throughout the body. Even though a patient with CC-TGA has properly oxygenated blood in the body and over the short term the right ventricle is able to handle the increased workload, eventually this ventricle will fail.
“It was amazing to see the heart up close in 3-D. It was such a great way to learn and gain a better understanding of the structure of the heart.”
When it comes to treatment for CC-TGA, there is no medical consensus. Because of the extreme rarity of this condition, there simply aren’t enough cases to conduct a substantial study and collect meaningful data on which to base a standard treatment protocol. That’s part of what inspired Dr. Hraska to hold The Heart Summit.
“Nobody really knows what the right strategy is. Everybody has their own protocol but there are no guidelines on how to approach these patients,” said Dr. Hraska. “That’s why we invited experts from other institutions to combine our experience with theirs. Hopefully we can get a better understanding of how to approach this defect.”
Some doctors suggest doing nothing — referred to as “watchful waiting” — until the right ventricle begins to fail. At that point, however, the function of the right ventricle usually cannot be restored with medical therapy and a heart transplant may be required to save the patient’s life. But Dr. Hraska — and many other doctors — believe that a transplant is not a cure, that you’re simply swapping one ailment for another. Many patients find the stress and maintenance of a transplant to be just as arduous as a case of CC-TGA.
Dr. Hraska believes an anatomical “double switch” correction — surgically reversing the defect and restoring the right and left ventricle to their proper function — as soon as the baby is physically able has the best outcomes long term. In the last 20 years, Dr. Hraska has performed more than 70 such surgeries and that’s the procedure he demonstrated during the live 3-D surgery at The Heart Summit.
“The essential idea behind The Heart Summit was to create a platform for the exchange of ideas and information,” Dr. Hraska said. “We wanted to take the classic medical conference model and make it more interactive and engaging.”
While more than 160 medical experts sat and watched, starting at 8 a.m., the surgical team put the boy under general anesthesia and then onto a heart-lung bypass machine; they made a three-inch incision down the middle of his chest and spread his ribs open; they placed a patch in the atria to route the blue blood to the right ventricle and the red blood to the left ventricle; they patched a hole between the two ventricles; they disconnected the pulmonary artery and aorta and reattached them to the correct ventricles; they then weaned the boy off the bypass machine, closed the incision and took him to the cardiac ICU for recovery. The whole procedure took just over six hours.
Not only were the attendees able to see and hear everything taking place in the operating room in real-time, they even had the ability to speak and interact with Dr. Hraska. Some asked questions about particular steps of the procedure and why certain choices were made, others commented on Dr. Hraska’s techniques and skills and a couple even offered suggestions for ways to conduct the repair.
While the 3-D was visually stunning — excited murmurs filled the room when the 3-D glasses were first activated and some even leaned forward in their seats and craned their necks trying to look deeper and peer around corners— Dr. Hraska also believes it’s a superior teaching tool.
“You can more clearly see the structures of the heart, their relationship and how they’re connected and organized,” Dr. Hraska said. “That helps you understand the complexity of the procedure.”
In addition to the live surgery, doctors from some of the world’s leading health care institutions — Boston Children’s Hospital, Evelina London Children’s Healthcare, the Mayo Clinic, Advocate Children’s Hospital and Children’s Hospital of Philadelphia — presented on a variety of CC-TGA topics. Subjects included the history of the malformation, an examination of the different treatment options, fetal assessment and post-operative complications, among others.
Children’s Hospital of Wisconsin is committed to innovation, collaboration and education to ensure the very best outcomes for patients. Being a truly world-class hospital means not just utilizing the latest techniques, but also pioneering them and teaching them to others. It means turning those groundbreaking methods into the standard. That’s the philosophy of Children’s Hospital of Wisconsin — and that was the philosophy behind The Heart Summit.