State of the Union: Pediatric Heart Surgery

Pediatric cardiac surgery has always demanded precision, endurance, and trust. But over the last three decades, the field has undergone a rather quiet evolution, becoming safer, less invasive, and more imaginative in how it approaches even the most complex cases.

In this State of the Union conversation, Emile Bacha, MD, pediatric heart surgeon and Chief, Division of Cardiac, Thoracic, & Vascular Surgery, reflects on how pediatric heart surgery has evolved, why Columbia continues to take on the cases others cannot, and where innovation, from partial heart transplantation to 3D modeling and xenotransplantation, may lead next.

Redefining What’s Possible in Complex Care

When you look at where pediatric cardiac surgery stands today, what feels most different from when you began?

Pediatric cardiac surgery is inherently risky. We’re doing open heart surgery on very small babies—sometimes a day old, sometimes only a few hours old. To fix the heart, we have to stop it, go inside these tiny hearts with micro-instruments, perform the repair, and then restart the heart. And that heart then has to function for a lifetime, beating billions of times.

What’s most striking is how much safer and less invasive the field has become. I finished my training in 1998, almost 30 years ago, and the change hasn’t come from one single breakthrough. It’s been many small advances, better ICU care, better drugs, better heart-lung machines, better surgical techniques, and a much deeper understanding of how to perform these operations with fewer complications.

Columbia has become known for taking on extraordinarily complex cases. What does “complexity” mean to you today?

That’s true not just in pediatric cardiac surgery, but across the Columbia/NewYork-Presbyterian system. One of the hallmarks of this institution is that we tackle the most difficult, complex, and often seemingly hopeless cases.

When I arrived here, it was immediately clear that the ICUs were filled with highly complex patients, and that’s still the case. If anything, the complexity has increased. Trainees who come from other hospitals are often surprised by how few “simple” cases we see here.

Because we’ve had good outcomes, we’ve attracted an incredibly complex patient population. We routinely take referrals from across the country. Just recently, we discussed a patient from Indiana whose local team felt there were no options left. That patient came here, underwent a procedure, returned home, and is now coming back for a final stage. That kind of story is very common for us, and it’s true across many surgical disciplines at Columbia.

How does that culture of complexity intersect with innovation, particularly in transplant?

Transplant is a major strength here, not just heart transplant, pediatric and adult, but transplant across the board: liver, kidney, pancreas, intestinal, multi-organ transplant. We’ve done triple-organ transplants. There’s really nothing we haven’t transplanted at this point.

And by definition, transplant puts you in a higher-complexity lane. What makes Columbia special is that we don’t accept failure as the final answer. We keep thinking about different ways to manage patients who are otherwise considered hopeless.

That’s true from nursing care all the way through surgical and technical care. Patients get physicians who are thinking deeply about their problems. You have world-class surgeons here who are constantly thinking about different ways to do things better. That mindset certainly drives innovation.

With valve disease, how has partial heart transplantation changed what’s possible for children?

Valve disease is extremely common in children. Traditionally, when we replace a valve in a child, we use prosthetic material, and that valve doesn’t grow. So if a child outgrows it, they need another operation.

The promise of valve transplantation is that the valve grows with the patient. We know that transplanted hearts grow as children grow. Our experience with valve transplantation is now about three years in, and so far, it appears that the valves do grow. That’s incredibly exciting.

What’s holding us back isn’t the medicine; it’s regulation and allocation systems that haven’t caught up with what’s now possible. We need the legislation from Washington, the FDA, to follow where the medicine is going.

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How have preservation strategies and immunosuppression enabled these advances?

This is a perfect example of how progress comes from many small improvements. Immunosuppression has changed completely. We’re now using far fewer drugs, with much better tolerability. For valve transplantation, we’re often down to a single medication instead of three.

Organ preservation has also improved dramatically. Liver and lung transplants can now be done electively instead of doing these cases at two in the morning, which is much better for everyone. For hearts, we’re not quite there yet, but preservation has improved enough that we can do much more than we used to.

Rethinking Single-Ventricle Disease

Let’s discuss approaches to ventricular repair. Has the approach changed around single-ventricle and biventricular pathways?

I’m going to take a few steps back, because this is important to explain clearly.

Single-ventricle circulation is a form of heart anatomy where a patient has just one pumping chamber. A normal heart has two ventricles: a left ventricle that pumps blood to the body, and a right ventricle that pumps blood to the lungs so it can be oxygenated before returning to the heart and back out to the body.

In single-ventricle patients, there is only one systemic pump, one ventricle doing the work of supplying the body. The rest of the circulation relies on passive blood flow, particularly to the lungs. That is not a natural state of being.

Because of that, these patients often develop problems over time. They frequently end up needing a heart transplant. They often cannot function physically the way other patients can; they’re limited in sports and athletic pursuits, and their long-term health is affected in ways that compound over decades. For many years, the field accepted this pathway as the only option.

So how does the biventricular approach work?

Over time, surgeons and cardiologists have pushed the boundaries, asking whether some of these patients could be moved from a single-ventricle circulation toward a two-ventricle circulation.

That can mean growing a ventricle that was previously considered too small, or changing blood flow patterns so that, over time, the ventricle develops enough to take on more work. At Columbia, we have a dedicated team under Dr. Andrew Goldstone focused specifically on this approach.

The goal is to move patients either to a true two-ventricle circulation or to what we call a one-and-a-half-ventricle circulation. A one-and-a-half-ventricle circulation is still better than a single ventricle. In that setup, part of the blood is actively pumped to the lungs, and the remainder flows passively. It’s not perfect, but it’s a significant improvement.

Twenty-five years ago, nobody was talking about doing this kind of work. Today, we can offer hope to families who previously had very few options.

What does this mean for long-term outcomes?

It depends on the anatomy and the pathway a patient follows. These are statistical curves, so there are always outliers, both good and bad, but broadly speaking, if a patient remains on a single-ventricle pathway, by their twenties or thirties they often require increasing levels of medical intervention.

That might mean more medications, more surgeries, or eventually a heart transplant. In some cases, it can mean a combined heart-liver transplant. The reason for that is the Fontan circulation, which is the classic single-ventricle pathway. Because blood flows passively through the liver in that system, the liver can be damaged over time.

We perform several heart-liver transplants each year, and we are one of the largest centers in the country with that expertise.

3D Mapping and New Technologies Expand Anatomical Access

How is the field continuing to advance?

One major reason this work is advancing is that our ability to understand heart anatomy has improved dramatically.

A normal heart is fairly complex already. If we just talk about the ventricles, you have two pumping chambers that are fused to each other, separated by a muscular septum. It's a muscular pump. And it's pumping in a certain way, in concert.

When you have congenital heart disease, it can affect any of these structures—the ventricles can be too big or not big enough, the septum can be in the wrong place, and not only the wrong place but too big or too small. There can be holes everywhere. So, it’s a real maze; these are extraordinarily complex three-dimensional structures. It’s like being in a forest and you don’t really know where to go. So you really need to study the anatomy.

Have new technologies helped map out these complexities?

Yes, absolutely. Here, we use advanced 3D reconstruction technology led by Dr. Giovanni Ferrari. These reconstructions allow us to see the inside of the heart in ways that were not possible before, either on specialized screens, through virtual-reality goggles, or via 3D-printed models.

This technology is essential for planning two-ventricle repairs, particularly procedures like ventricular septation, where a new septum is created inside the heart. It allows surgeons to understand which structures should be preserved, which need to be modified, and how best to reconstruct the heart safely.

Surgical Training Advances, and the Bright Road Ahead

How has 3D modeling changed surgical planning and education in other areas of pediatric heart care?

With 3D reconstruction and printing, it’s actually transformed how we teach. Trainees can now practice repairs on printed heart models before ever stepping into the OR. We’ve built a strong simulation program, supported by a generous anonymous gift from a grateful family, which has allowed us to expand 3D printing and simulation training across the program.

When I was training, it was very much an apprenticeship. You worked with more senior surgeons, helped them, and gradually you would do more and more surgery. It’s like a pilot and a co-pilot. The passengers don't really know who's flying the plane between them. An inexperienced co-pilot is basically helping the pilot, and then over time doing more and more, graduating to be the pilot.

And in aviation, simulators are required to complete training. You get simulated with plane crashes and all different things. It’s the same with surgery now. We can print out models of a heart fairly cheaply these days, which we couldn't do before. For example, we give a printed-out heart model of a particular lesion, and say, “Go to the lab and practice a certain surgical repair on that 3D model.”

What role does robotics play in pediatric cardiac surgery?

Robotics has been transformative, particularly in adult and congenital repairs. When Dr. Arnar Geirsson [Director of the Surgical Heart Valve Program] joined us, he came as a fully mature robotic cardiac surgeon for adults. And, I've said this before, but after I saw his first case and how excellent he was, I told him, if I ever need a mitral valve repair, which is his specialty, “You are doing it and you're doing it robotically” because wow, you can see inside the heart much better than you can with open heart surgery.

When you're looking with your eyes, you cannot go around corners. But when you insert the camera, you capture different angles, and you can see very, very well. It's almost as if you're standing inside the chest and you can look up, look down, look backwards because you can move the camera around.

For children above a certain size, we can already use adult robotic instruments. For smaller children, instrument size remains a challenge, largely because the market is small. It’s not prioritized by these companies, but we’re actively working on it.

And then the final important thing to mention with robotics is that it's so minimally invasive, meaning you are avoiding a sternotomy and a division of your breast bone, which is really what patients complain the most about after surgery. The heart surgery isn't what bothers them. Typically, they feel better, but it's the bone incision that's a problem. And so avoiding that is really a big advantage.

Looking ahead, what breakthroughs feel within reach?

Xenotransplantation is one of the most promising areas, especially for children. It’s when you take an organ from a genetically modified animal, typically piglets, and implant them into patients who need them. It’s already being performed in China, both heart and kidney xenotransplant. The results are mixed at best, but that’s true any time a field is burgeoning.

This is particularly interesting for us in the pediatric arena for several reasons. Young patients don’t have good mechanical support options. When we put ventricular assist devices (VADs) in adults, it’s fairly standard and can be supported for years on end. But in children, we have very imperfect devices.

Number two, donor organs are scarce. The number of kids dying while waiting for a heart is pretty high. And children don’t need lifelong solutions, sometimes they just need a bridge to the next stage, something that gets them from say 6 months to 6 years of age. We’re not talking about organs that need a lifespan of 60 years, just a few to get them from point A to point B.

And finally, children have more adaptable immune systems, which may allow for greater tolerance of xenografts. The younger you are, the more we can manipulate your immune system. For all these reasons, pediatric xenotransplantation holds enormous potential and is a very important field.

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Access, Accountability, and the Surgeon’s Role

How do you think about patient access to high-quality pediatric heart care?

I would say that in some ways, we’re victims of our own success. Demand is high, and ICU availability isn’t good; it can be tight. You feel bad for patients waiting to get in, but we work closely with the hospital and across campuses to ensure patients get care as quickly as possible.

On the pediatric side, operating at the Cornell campus [Note: Cornell, like Columbia, is a partner of NewYork-Presbyterian, with some programs–like pediatric heart surgery–working across both campuses] has allowed us to increase access and flexibility, which has made a meaningful difference for families. Recently, we had a patient who was canceled because there were no ICU beds. We asked the family, “Do you mind if we do the surgery at Cornell?” They said, Yes. A few days later, we're able to do it at Cornell, and everybody was happy.

What defines a great pediatric heart surgeon today?

That hasn’t changed. What defines a great surgeon is the same thing that defines a great pediatric surgeon. Pediatric heart surgery is maybe more magnified because the line between life and death is so much closer; you make a mistake, and you can literally lose the patient. You can not afford to make certain mistakes, ever. Whereas other types of surgery aren’t so dangerous inherently.

But the hallmarks of a great surgeon—technical dexterity is essential, and equally important is a steady mind. When things go wrong, and they will, the surgeon has to remain calm, cool, collected and lead the team. If you get upset, people don’t function at their best.

You have to stay very steady. A surgeon cannot be just a technician. You must understand perioperative care, cardiology, imaging, and the full arc of patient care. Ultimately, the responsibility for outcomes rests with the surgeon.

Steady hands, steady mind, and a good clinician.

Finally, what is the most meaningful part of your work?

I just love my job, and I am so grateful, blessed really. When you have grateful families, nothing beats that. Just this morning, I received an email from a family in Hong Kong marking the anniversary of their child’s surgery. Their child is thriving, living life. Nothing is better than that. Getting to see the pictures of these kids growing and smiling, it’s everything.

The other part I love is training young surgeons and seeing them develop into competent, ethical surgeons and succeed around the world. I have trainees in Canada, Australia, Germany. It’s amazing to see their successes. And the last thing is innovation, pushing boundaries of research and seeing those efforts improve care, is incredibly fulfilling.

I feel incredibly lucky to do what I do.