Dr. Bret Mettler Strives to Make a Lasting Difference for Children and Families
Long before he became a leader in pediatric cardiac surgery, Bret Mettler, MD, entered medicine through a love of science and discovery. But it was the moments at the bedside, where he saw the difference his care made in the lives of children and their families, that gave his career its true meaning.
“I kind of meandered my way into pediatric cardiac surgery,” Dr. Mettler says. “I fell in love with the technical sophistication, the complexity of the operations, and the range of pathology we see, but as important was being able to make a difference to someone for potentially a whole entire life — not just a few years of life, but 60, 70, 80, 90 years of life.”
That passion for making a lasting impact led Dr. Mettler to Memphis and the University of Tennessee Health Science Center, where he is chief of pediatric cardiac surgery and the Susan and Alan Graf Endowed Chair in Pediatric Heart Surgery. He also serves as executive co-director of the Heart Institute at Le Bonheur Children’s Hospital, the university’s primary pediatric partner, alongside Executive Co-Director Jason Johnson, MD, chief of pediatric cardiology.
Dr. Mettler came to Memphis from Johns Hopkins Children’s Center in Baltimore, Maryland, where he served as director of pediatric cardiac surgery and co-director of its heart center. Before that, he was director of cardiac transplantation and mechanical circulatory support at Vanderbilt University Medical Center in Nashville.
Because his move to Johns Hopkins happened during the COVID-19 pandemic, his family stayed in Tennessee and deepened their ties to the Volunteer State. “My family got used to being in Tennessee, and we went back and forth to see each other,” he says.
With a southern wife and two daughters who have only ever been Tennesseans, the chance to return felt like coming home. “We love being back in the South. We like the warmth, the openness, the inquisitiveness. I prefer to be back down in an environment with that southern hospitality, which is what we’ve known our whole lives and our daughters have grown up in,” he says.
But the move was about more than geography. Dr. Mettler was drawn to the unique opportunities at UT Health Science Center and Le Bonheur. Under the leadership of the previous executive co-directors — Chief of Pediatric Cardiac Surgery Christopher Knott-Craig, MD, and Chief of Pediatric Cardiology Jeffrey Towbin, MD — the Heart Institute advanced into a top 10 program. Additionally, U.S. News & World Report has named Le Bonheur one of the nation’s “Best Children’s Hospitals” for 15 consecutive years, and the hospital recently completed a $95.4 million expansion, much of which is dedicated to caring for children with congenital cardiac disease.
“There was a rich history of congenital cardiac care here, started by visionary leaders, and an administration who had desires to not only maintain but to grow a pediatric heart institute to levels which hadn’t been realized before,” he says.
For Dr. Mettler, this environment created the ideal conditions for both clinical excellence and innovation. “It’s an exciting place for someone like me, who wants to provide excellent clinical care and research to work our ideas and foster the next generation of ideas.”
That work is supported by UT Health Science Center and the Methodist Le Bonheur Healthcare system, which together foster a collaborative environment where new programs and research initiatives can thrive. For Dr. Mettler, being part of the academic medical setting at Le Bonheur, where most physicians are affiliated with UT Health Science Center, has been critical. In addition to the resources the College of Medicine provides for obtaining and administering research grants, the academic environment brings together like-minded faculty committed to advancing their field.
“We have a mission as faculty members at an academic institution for scientific discovery and to improve care for the next generation. We take that responsibility in the Heart Institute and pediatric cardiac surgery extraordinarily highly,” he says. “Our mission is to continue to advance discovery within pediatric cardiac surgery across all parts of the Heart Institute, whether it be pediatric cardiology, pediatric cardiac critical care, or pediatric anesthesia.”
“If we always keep patients at the center, we will always lead to making the right decision.”
Dr. Bret Mettler
Since arriving in late 2024, Dr. Mettler has wasted no time building on this foundation. He recruited a partner from Johns Hopkins, Associate Professor Danielle Gottlieb Sen, MD, MPH; launched a pediatric cardiac research institute; and set ambitious goals for the future, including establishing subspecialty centers for complex conditions and advancing research in remote and device monitoring for children. Additionally, a top priority is to grow a program for adults born with heart disease.
“There are now more adults alive with congenital heart disease than kids. That tells us that we’ve gotten better at our job,” Dr. Mettler says. “We have a bunch of these patients who are now adults, who have adult problems that need pediatric-type operations. That’s one of the things we do as congenital cardiac surgeons — care for adults with congenital heart disease.”
As a surgeon and a leader, Dr. Mettler says he has two main responsibilities. He strives to help the faculty reach their full potential, fostering their curiosity and ideas, and giving them the space to lead in clinical care. At the heart of it all, though, is a responsibility to patients and families, focused on excellent care and outcomes.
“We always want to keep the patients at the center,” Dr. Mettler says. “There will be times when we have to make challenging decisions for the institution, for the health system, for the medical school, or for me personally, but I think if we always keep patients at the center, we will always lead to making the right decision.”
As he looks ahead, Dr. Mettler is optimistic about what is possible. “The environment I’ve found myself in is real fertile ground for growth, development, and acceptance of us as new heart surgeons in the community, but also for us in regards to providing care for patients and families. I’m excited for what we can achieve together.”
Pediatric Cardiac Care ‘Felt Like Part of Who I Was,’ Dr. Jason Johnson Says
For Jason Johnson, MD, MHS, the path to a career in pediatric cardiology was not a straight line. Dr. Johnson initially studied animal sciences in college, with dreams of becoming a veterinarian or marine biologist. The biological sciences — specifically, the human heart — kept calling him, though. And the root of that call stems from a deeply personal place.
“My brother was born with severe congenital heart defects and only lived 11 months. I was 5 years old when he died,” Dr. Johnson says. “I think that experience is why I was drawn to this field; it felt like part of who I was.”
Recently, Dr. Johnson was named chief of Pediatric Cardiology and Bob and Paula McEniry Endowed Chair of Cardiology. He is also executive co-director of the Heart Institute at Le Bonheur Children’s Hospital, an appointment he says feels less like a new beginning and more like the next natural step in a journey more than a decade in the making. Dr. Johnson joined the Heart Institute in 2013 following residency and fellowship training at Duke University, bringing with him a clinical passion for advanced cardiovascular imaging and a sense of purpose grounded in his personal experience.
“At the time, I was the 13th cardiologist on staff,” he recalls. “Now we have 34. I might not have envisioned all this program would become, but even then, I could see tremendous opportunity for growth and specialty expertise — the chance to help shape something with enormous potential, right from the ground floor.”
Asked about his greatest career achievement, Dr. Johnson states without hesitation that his proudest accomplishment is “the connections I’ve built with my families.
“You’re here long enough and you build meaningful relationships, and that’s why we’re here, is to take care of our patients,” he says.
In fact, Dr. Johnson is finding meaningful ways to care for patients not just in his clinical practice, but through his work on the global stage. As editor-in-chief of Cases of SCMR for the Society of Cardiovascular Magnetic Resonance, he helps educate providers from around the world on advanced imaging techniques, supporting knowledge-sharing across borders and empowering physicians to bring new modalities of care back to their home countries.
“We will continue growing the infrastructure and recruiting the right people so that every child can get the exact care they need right here at Le Bonheur.”
Dr. Jason Johnson
Dr. Johnson brings that same collaborative and holistic approach to leadership, helping to bridge knowledge gaps and build cohesion across disciplines.
“In subspecialty care, it’s easy to get siloed. But our patients deserve coordinated, expert care,” he says. “I see my role as making sure each team has what they need to do their best work.”
Thankfully, as a cardiac imager, Dr. Johnson often finds himself at the crossroads of multiple subspecialties.
“One day I’m in outpatient general clinic, the next I’m reading echocardiograms in the ICU, the next I’m doing MRIs or seeing patients at St. Jude Children’s Research Hospital,” he says. “I touch every aspect of our division and get to see everybody in action, and that perspective helps me understand what each team needs to succeed.”
As he steps into the role of chief, Dr. Johnson’s vision is rooted in this commitment to expertise-driven care. His goal? That no child in the Mid-South with congenital heart disease should ever need to leave the region for treatment.
“We will continue growing the infrastructure and recruiting the right people so that every child can get the exact care they need right here at Le Bonheur,” he says.
That growth includes planned 4D enhancements to the hospital’s Virtual Reality Lab, allowing physicians to practice procedures on simulated, beating hearts that emulate blood flow in real time.
Yet for all the groundbreaking advancements, Dr. Johnson remains focused on what matters most.
“New technologies are incredible, and it’s inspiring to see the progress in our field over the last few decades,” he says. “But the core of our work will always be those relationships with families, helping them feel seen, heard, and cared for. That’s what keeps me coming back.”
Haley Overcast, director of Marketing and Communications at Le Bonheur, contributed to this story.