Researchers and surgeons at Children’s Healthcare of Atlanta, Emory University and Georgia Tech led the first-ever Phase 1 clinical trial using patient-specific stem cells to help heal the hearts of babies born with hypoplastic left heart syndrome (HLHS), a severe congenital heart defect.

The stem cells, known as autologous neonatal cardiac progenitor stem cells, were injected into the right ventricle of babies’ hearts for the first time during the trial after several preclinical studies showed the therapy may help treat surgery-related damage to the right ventricle.

Babies born with HLHS do not have a functioning left side of the heart and require surgery shortly after birth. They undergo three surgeries during their first three years of life to redirect blood flow through the right ventricle of the heart. This single right ventricle, doing the work of both the left and right ventricles, is under a lot of stress, with a high risk of severe complications. As a result, the right ventricle can fail, often leading to a shortened life.

“For a baby with a congenital heart defect like HLHS, we can try to strengthen the heart and prevent deterioration of its existing tissues while the baby is young and the heart is still developing,” said Michael Davis, PhD, Principal Investigator and Director of the Children’s Heart Research and Outcomes (HeRO) Center and Professor of Biomedical Engineering at Georgia Tech and Emory.

The injections showed many clinical benefits, including a reduction in mortality and the need for heart transplantation, a reduction in major adverse cardiac events, shorter hospitalizations and improvements in quality of life. Results, co-authored by William Mahle, MD, Chief of Cardiology and Co-Chief of the Heart Center at Children’s and Marcus Professor of Pediatrics at Emory, were published in the Journal of the American College of Cardiology: Heart Failure. Dr. Davis and the research team hope to complete a Phase 2 trial following these promising results.