Pushing the Boundaries of Innovation in Pediatric Heart Valve Repair and Replacement

At the NewYork-Presbyterian, cardiac surgeons at the Pediatric Heart Valve Center are pushing the boundaries of innovation in pediatric heart valve repair and replacement to improve the survival and quality of life of children with congenital heart defects, a leading cause of death in infancy.

Congenital heart defects comprise at least 35 types of abnormalities of the heart that range from mild and treatable to complex and life-threatening. In recent years, major advances in the surgical, medical, and ICU treatments of children with congenital heart defects has vastly improved their survival, yet many still suffer from the effects of their long-life disease.

image of Dr. David Kalfa

Dr. David Kalfa

“Our goal is to give neonates, children, adolescents and young adults with congenital heart disease the best chance of survival, minimize the risk of reintervention, and enable them to attain the longest life expectancy and the highest quality of life,” explains David Kalfa, MD, PhD, Director of the Pediatric Heart Valve Center and Surgical Director of the Initiative for Pediatric Cardiac Innovation at NewYork-Presbyterian. “At the Center we see some of the most complex and challenging cases, which propels us to think outside of the box to conduct collaborative and translational research that will address valve-related and heart failure-related unmet clinical needs.”

The Pediatric Heart Valve Center is one of the largest pediatric cardiology and cardiac surgery centers focusing on heart valve congenital malformations in the nation. Here, a multidisciplinary team from our two children’s hospitals – NewYork-Presbyterian Morgan Stanley Children’s Hospital and NewYork-Presbyterian Komansky Children’s Hospital – consisting of pediatric cardiac surgeons, interventional cardiologists, anesthesiologists, cardiologists, pediatricians and perfusion, critical care and cardiovascular support specialists perform the latest gold standard surgical techniques with outcomes that are among the best in the nation.

“Our Center is one of the few in the nation to offer the Ozaki technique, an innovative procedure that involves removing the patient’s diseased aortic valve and recreating a new valve with leaflet templates made from a tissue substitute taken from the patient’s own pericardium or bovine pericardium,” says Dr. Kalfa. “The Ozaki technique is an alternative to the Ross procedure, which is still the gold standard surgical therapy for aortic valve dysfunction in which the aortic valve is replaced with the patient’s pulmonary valve.”

“We are also one of the few in the nation to perform complex neonatal surgery in low weight (as low as 1.5 kg) and premature infants including the Norwood procedure and interrupted aortic arch repair with remarkable outcomes,” continues Dr. Kalfa.

For babies born with hypoplastic left heart syndrome (HLHS), a rare congenital defect that affects the heart’s ability to pump blood throughout the body, the Norwood procedure is the first of a three-step process to create normal blood flow through the heart. For Norwood too, the Pediatric Heart Valve Center at NewYork-Presbyterian Morgan Stanley brought innovation. “We recently started to incorporate a valve in the connection between the single ventricle and the pulmonary arteries — what we call a composite valve Sano — as part of the Norwood procedure. This may improve the growth of the pulmonary arteries and help with the function of the ventricle in these fragile babies,” explains Dr. Kalfa.

Dr. Kalfa also provides minimally invasive axillary repairs for congenital heart defects that are accessible through the right atrium and involves a small incision below the arm on the right side of the chest, thereby avoiding a scar on the front of the chest. “The side location of the scar is associated with impressive psychological and social benefits for children who don’t see the scar as easily because it is hidden below the arm,” says Dr. Kalfa. Dr. Kalfa now minimizes these small incisions even further (down to 2 to 3 cm) for open-heart surgery by employing a video-assisted technique that visualizes the interior cavity and using peripheral cannulation as opposed to central cannulation.

Driven by his passion for innovation and improving the lives of children with congenital heart defects, Dr. Kalfa launched the Initiative for Pediatric Cardiology Innovation in 2019, where he collaborates with mechanical, electrical, chemical and biomedical engineers on translational research projects. “We formed this Initiative to assist the adoption of groundbreaking surgical, transcatheter and imaging techniques and technologies in the divisions of Pediatric Cardiac Surgery and Pediatric Cardiology, educate surgical and medical fellows and residents about innovations in the field, and promote research that provides our patients with access to the latest minimally invasive procedures and technologies and more personalized treatments,” says Dr. Kalfa, who received enthusiastic support from Emile Bacha, MD, Chief, Congenital and Pediatric Cardiac Surgery at NewYork-Presbyterian Morgan Stanley, and Julie Vincent, MD, Chief, Division of Pediatric Cardiology at NewYork-Presbyterian Morgan Stanley. Dr. Kalfa is working closely on this Initiative with Kanwal Farooqi, MD, Director of Cardiac 3D Printing, and Matthew Crystal, MD, Director of Inpatient Cardiology specializing in transcatheter interventions who serves as Associate Director of the Pediatric Catheterization Laboratory at NewYork-Presbyterian Morgan Stanley.

One research project of the Initiative involves the use of polymers and tissue engineering to create replacement valves that can grow and conform to children’s anatomy over time. “After implantation, the tissue engineering part of the valve can grow since it is made with living autologous tissue from the patient while the polymer part of the valve can be expanded by noninvasive balloon dilation in the cath lab,” explains Dr. Kalfa. “This new valve will reduce the need for multiple surgeries, thereby improving children’s quality of life.”

“In-vitro studies of the polymer and neo-tissue valves have already been completed with excellent results,” says Dr. Kalfa. “We are now moving toward implantation in animals to assess the performance of these valves.”

Dr. Kalfa and his research team are also developing in his lab new biomaterials that allows for durable heart valve repairs based on a biomimetic approach (synthetic materials that mimic the architecture of a normal valve) and biocompatible polymers.

In acknowledgment of his groundbreaking research achievements, Dr. Kalfa recently received the prestigious American Heart Association (AHA) and the Children Heart Foundation (CHF) Congenital Heart Defect Research Transformational Project Award for his work the in-vitro and in-vivo mechanical stability and growth of a bio-hybrid heart valve.

On yet another frontier, Dr. Kalfa and his lab team are melding artificial intelligence and precision medicine to provide personalized treatment to children with heart failure. “We are developing soft robotics-based cardiac compression device technology that has soft sensing and soft actuation, a novel approach to treating pediatric heart failure,” he explains.

The dynamic interplay between bench and bedside continues to fuel Dr. Kalfa’s passion for innovation in the treatment of congenital heart defects. “My clinical experience enables me to identify unmet clinical needs and think about the sorts of new devices I can develop in my lab,” says Dr. Kalfa. “This, in turn, gives me fresh perspectives about how technology can be applied to my clinical work, which allows me to help my patients in unique and novel ways.”