Researchers at Mayo Clinic have developed a pioneering method to repair damaged hearts without the need for open-heart surgery, an advance that could one day transform the treatment of heart failure. The new approach uses heart tissue grown in the lab from reprogrammed adult stem cells, applied through a small incision instead of surgically opening the chest cavity. Early attempts showed promising results, but most required open-heart surgery — a procedure too risky for many patients who already suffer from severe heart failure. "For this reason, heart failure, especially chronic heart failure due to the loss of functional heart muscle, is often difficult to treat; the muscle simply cannot repair itself," the text states. For years, scientists have been working on ways to replace damaged tissue with healthy heart cells derived from stem cells. In preclinical tests, the stem cell patch restored heart function and improved healing. "For patients with severe heart failure, there are very few options beyond mechanical pumps or heart transplants," the text says. In collaboration with engineers from the University of Nebraska Medical Center, the Mayo researchers developed a flexible, ultra-thin patch made of nanofibers and microfibers coated with gelatin. This hybrid scaffold serves as a support for a combination of human heart muscle cells, blood vessel cells, and fibroblasts — the cells that form the structure of tissue — thereby creating a living, pulsating piece of heart tissue. Before transplantation, the tissue is infused with bioactive factors such as fibroblast growth factor 1 and CHIR99021, which stimulate the growth of new blood vessels and help the cells survive once implanted. Instead of using sutures, the team employed a biocompatible surgical adhesive that holds the patch in place while minimizing additional trauma to the surrounding tissue. Tests conducted in preclinical models showed that this minimally invasive method improved heart function, reduced scar formation, promoted vascular growth, and decreased inflammation compared to conventional approaches. "Our results show that these engineered tissues not only survive but actually help the heart heal itself," says Dr. Zhu. "That is the ultimate goal: to replace what has been lost and restore function." The research aligns closely with Mayo Clinic's Genesis Initiative, which aims to accelerate discoveries that enable the restoration or regeneration of human organs and tissues. "Genesis is about forging new paths to repair and rebuild the human body," says Dr. Zhu. The Mayo Clinic team plans to advance this work by conducting larger-scale preclinical tests to ensure the therapy's safety and efficacy before moving to human clinical trials, a process Dr. Zhu estimates could take five years or more. "Heart failure remains a devastating condition," he says. Dr. Zhu hopes this technology can offer, over time, another alternative. "Our vision," he asserts, "is that patients can one day receive heart tissue engineered from their own reprogrammed cells, applied via a minimally invasive procedure — no donor organ, no long recovery, just a repaired heart."
