Bioengineering team from Trinity College in Dublin develops a prototype patch that does the same job as crucial aspects of heart tissue.

One in six men and one in seven women in the EU will suffer a heart attack at some point in their lives. Worldwide, heart disease kills more women and men than any other disease and bioengineering might deliver a solution.

Longevity.Technology: Cardiac patches lined with heart cells can be applied surgically to restore heart tissue in patients who have had damaged tissue removed after a heart attack. Ultimately, though, the goal is to create cell-free patches that can restore the synchronous beating of the heart cells, without impairing the heart muscle movement.

The Trinity bioengineers reported their work [1] in the journal Advanced Functional Materials and demonstrate that they have taken on step closer to a deployable solution.

“Despite some advances in the field, heart disease still places a huge burden on our healthcare systems and the life quality of patients worldwide,” said Michael Monaghan, professor in biomedical engineering at Trinity, and senior author on the paper. “As a result, researchers are continuously looking to develop new treatments which can include stem cell treatments, biomaterial gel injections and assistive devices.

“Ours is one of few studies that looks at a traditional material, and through effective design allows us to mimic the direction-dependent mechanical movement of the heart, which can be sustained repeatably. This was achieved through a novel method called ‘melt electrowriting’.”

The project highlights the potential applications of this technology; engineering replacement materials for heart tissue is challenging since it is an organ that is constantly moving and contracting. The functionality of thermoplastic polymers were leveraged through structural geometry; the bioengineers then set about making a patch that could control the expansion of a material in multiple directions and tune this using an engineering design approach.

The patch withstood repeated stretching, which is a dominant concern for cardiac biomaterials, and showed good elasticity, to accurately mimic that key property of heart muscle.

The patches were manufactured via melt electrowriting – a core technology of Spraybase®; they were also coated with the electroconductive polymer polypyrrole to provide electrical conductivity while maintaining cell compatibility. This work was performed in collaboration with Spraybase, a subsidiary of Avectas Ltd. It was funded by Enterprise Ireland through the Innovation Partnership Program (IPP).

Dr Dinorath Olvera, Trinity, first author on the paper, added: “Our electroconductive patches support electrical conduction between biological tissue in an ex vivo model. These results therefore represent a significant step towards generating a bioengineered patch capable of recapitulating aspects of heart tissue – namely its mechanical movement and electrical signalling.”

[1] onlinelibrary.wiley.com/…2/adfm.201909880