Dr. David Kalfa, professor and researcher at FIU Herbert Wertheim College of Medicine (FIU Medicine) and chief of cardiovascular surgery and co-director of the Nicklaus Children's Hospital's Heart Institute, has led the first partial heart transplant performed in the state of Florida—marking a major advancement in pediatric heart surgery.
The groundbreaking procedure, known as a Living Allogenic Valve Transplantation, was performed at Nicklaus Children's Hospital on 11-year-old Greyson, who received a "living" heart valve from a donor. Unlike traditional prosthetic valves, living valves can grow with the child, significantly reducing—or potentially eliminating—the need for future open-heart surgeries as the patient ages.
"Partial heart transplantation is redefining what's possible in pediatric heart surgery," says Kalfa. "By transplanting a living valve, we're not just repairing a defect—we're restoring heart function in a way that allows it to grow naturally with the child. Our goal is to move beyond temporary solutions and provide children with durable, life-changing outcomes."
Greyson, his family and his care team celebrate his discharge from the hospital. (Photo: Nicklaus Children's Hospital)
In a partial heart transplant, a living valve from a donor heart is implanted into the patient, allowing it to adapt and grow over time. This approach offers a powerful alternative to mechanical or animal-derived prosthetic valves, which cannot grow, often deteriorate, and may require lifelong blood thinners. These limitations frequently lead to multiple additional surgeries and are associated with lower long-term survival rates in pediatric patients.
Greyson had already undergone two heart surgeries as an infant before receiving care under
Dr. Kalfa's leadership. His family is hopeful that the living valve will allow him to grow without needing additional open-heart surgeries.
"Seeking a second opinion led us to Dr. Kalfa, whose expertise and research made all the difference," says Greyson's mother, Piera Archila. "After surgeries in New York and visits to several children's hospitals, we finally found an approach that offered our son a long-term solution."
Congenital heart defects are the most common birth defects in the United States, affecting nearly 1% of newborns—about 40,000 infants each year. Approximately half of those children will require surgery to repair or replace a heart valve.
Living valve transplants are time-sensitive, donor valves are typically implanted within 12 hours of recovery and patients require long-term medication to suppress the immune system and prevent the body from rejecting the donor tissue.
Dr. David Kalfa in his congenital heart research lab at FIU.
Kalfa's research at FIU --supported by a National Institutes of Health grant-- focuses on improving valve‑preservation techniques and reducing immune rejection. The goal is to extend the shelf life of donated valves so they can be stored until a child needs them.
To achieve this, the Kalfa Lab for Congenital Heart Research is refining an innovative preservation strategy to keep donated tissue viable for longer periods. Tissue is stored in a custom-built bioreactor that closely replicates conditions inside the body, using pulsing stimulation to mimic a heartbeat. A special solution—patented by Kalfa's team and proven to keep tissue alive for at least seven weeks—is added to "feed" the tissue and supply essential nutrients.
"This is definitely a new, exciting frontier," Kalfa says. "It could increase availability and the chance of having the right valve for the right patient at the right time."
Kalfa's joint appointment at FIU Medicine and Nicklaus Children's reflects the strength of this academic‑clinical partnership to advance research and deliver innovative, world‑class care for children in South Florida.
Angela Nicoletti contributed to this article.
