A cell-free patch has been developed by researchers from Trinity College Dublin to repair cardiac tissue damaged by a heart attack. The patch is fabricated with a medical-grade polymer and coated with a mesh of polypyrrole, an electroconductive polymer.

Engineering a patch for application to constantly moving heart muscles is challenging. Polyester-based The patch is fabricated with a medical-grade polymer and coated with a mesh of polypyrrole, an electroconductive polymer. Source: Trinity College Dublinthermoplastic polymers commonly used in medical devices do not possess sufficient mechanical integrity and the elasticity needed for this function. The researchers used melt electrospinning writing to fabricate an auxetic patch with enhanced elasticity and the mechanical properties required to accommodate the strains and stresses exhibited by the human heart. The synthesis process uses an electric field to control the deposition of a molten polymer jet, which rapidly solidifies into a fiber.

The patch was demonstrated to withstand repeated stretching and to incorporate electroconductive properties that mimic those of human heart tissue. The new material can facilitate the electrical signaling that naturally occurs between cardiac cells, and has the ability to synchronize to the contractions of the heart, minimizing mechanical stress.

After implantation, the patch should detect electrical signals of surrounding cardiac cells and transmit their signals across the gap while expanding and contracting in time with adjacent tissue.