Groundbreaking procedure allows heart repairs to grow with children, new study shows

Owen Monroe was 18 days old when he made history, becoming the first person in the world to receive a partial heart transplant. In a new study, his doctors will document another milestone: For the first time, the tissue used to fix Owen’s heart has grown, a long-sought goal of this type of repair.

Owen Monroe was 18 days old when he made history, becoming the first person in the world to receive a partial heart transplant. His groundbreaking surgery, performed in 2022, even captured the attention of Hollywood scriptwriters, who wove his story into a recent episode of the long-running medical drama “Grey’s Anatomy.” In a study published Tuesday in the journal JAMA, his doctors will document another milestone: For the first time, the tissue used to fix Owen’s heart has grown, a long-sought goal of this type of repair. At the time of his first operation, Owen’s heart was the size of a strawberry. Today, at 20 months of age, it’s about the size of an apricot – and the new valves and blood vessels have kept up with his growth, which means unlike most children born with the same defect, he may not need to have more risky heart surgeries throughout his life. Researchers have been working to make growing heart valves a reality through tissue engineering, germinating them from cells in a lab. That approach has worked in animals, but it has not yet panned out in humans. “This is a huge advance,” said Dr. Kathleen Fenton, chief of the Advanced Technologies and Surgery Branch of the National Heart, Lung, and Blood Institute. She wrote a recent editorial about the potential of partial heart transplants, but she was not involved in this research.