Can polyester patch up damaged hearts?

23 February 2020


Heart attacks leave heart tissue damaged in a way that’s hard to heal. Muscle cell death weakens the pumping action, and electrical signaling through the heart can be disrupted.

Now scientists at Trinity College Dublin have invented a unique new artificial tissue patch that can mimic the electrical conductivity of real heart tissue – and take the constant beating that comes with being applied to a living heart.

Trinity researcher Michael Monaghan said the study was one of few that used a traditional material to mimic the movement of the heart in a sustainable way.

The traditional material in question? A polyester-based thermoplastic polymer. These polymers are often used in medicine because of their biocompatibility, but are not normally strong enough to withstand constant stress from a human heartbeat – if you flex them repeatedly, they break.

The research team got around this by working with a company called Spraybase to use a novel technique called melt electrospinning writing (MEW). This alters the geometry of the material at a microscopic level, creating an auxetic material – one that, when stretched, becomes thicker rather than thinner.

With this method, they developed patches that could match the elasticity of real heart tissue. What’s more, the geometry of the patches can be fine-tuned to produce directional mechanical properties – useful with the directional movement of a beating heart – or non-directional properties.

By coating these patches with a conductive polymer, the research team also managed to match the electrical conductivity of the heart.

This material is not only compatible with existing heart tissue, but with new and growing heart cells, which means it could be used to support damaged hearts in repairing themselves by providing a matrix on which the heart can rebuild new cells.

With these innovative properties, it’s possible that the new patch could help cardiac patients recover from many of the effects of a heart attack.