Its only the beginning ...

Graphical abstract. Credit: Acta Biomaterialia (2025). DOI: 10.1016/j.actbio.2025.08.057

This is the first practical application of stem cell regeneration that will transform medicine forever as it will go far beyond repairing just hearts once the research proves to work in the real world.

Mayo Clinic researchers have developed a pioneering method to mend damaged hearts without open-heart surgery, an advance that could one day transform the treatment of heart failure.

The new approach uses lab-grown heart tissue made from reprogrammed adult stem cells, delivered through a tiny incision rather than a surgically opened chest cavity. In preclinical testing, 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 transplants. We hope this approach will offer a new way to repair their own hearts," says Wuqiang Zhu, Ph.D., senior author of the study published in Acta Biomaterialia and a cardiovascular researcher at Mayo Clinic in Arizona.

But safely and effectively delivering engineered heart tissues made from these cells has remained a major challenge.

In collaboration with engineers at the University of Nebraska Medical Center, Mayo researchers developed a flexible, paper-thin patch made of nano- and microfibers coated with gelatin. This hybrid scaffold supports a blend of human heart muscle cells, blood vessel cells and fibroblasts—cells that form the tissue's structural framework—to create a living, beating piece of heart tissue.

Before transplantation, the tissue is infused with bioactive factors such as fibroblast growth factor 1 and CHIR99021 that encourage the growth of new blood vessels and help the cells survive once they are in place.

"The beauty of this design," says Dr. Zhu, "is that it can be folded like a piece of paper, loaded into a slender tube, and delivered precisely where it's needed through a small incision in the chest. Once in place, it unfolds and adheres naturally to the heart's surface."

Instead of using stitches, the team used a biocompatible surgical adhesive that holds the patch in place while minimizing additional trauma to the surrounding tissue.

Its just the beginning ...