The biodegradable polymer scaffold encourages the body to grow new tissue

Researchers at Harefield Hospital and Imperial College London’s (ICL) National Heart and Lung Institute have suggested a new heart procedure to help the body grow replacement heart valves.

The treatment is developed to produce a living valve in the body that would be able to grow with the patient.

Currently, heart valve replacement treatment has medical drawbacks with both the mechanical and biological valves, which only last between ten and 15 years. In most cases, patients must take drugs for the rest of their lives to prevent blood clotting.

Beginning with a nanofibrous polymeric valve made from a biodegradable polymer scaffold, Dr Yuan-Tsan Tseng, a biomaterials scientist at ICL’s National Heart and Lung Institute and the Harefield Heart Science Centre, explained that “the scaffold recruits cells and instructs their development so that the body works as a bioreactor to grow new tissue”.

“The scaffold gradually degrades and is [replaced] by our body’s own tissues,” he added.

In a previous study, these types of valves were transplanted into sheep and monitored for up to six months, which showed good cellular regeneration – the scaffold was successfully able to attract cells from the blood stream to develop into functional tissues, otherwise known as endothelial-to-mesenchymal transformation.

“We’ve also seen nerves and fatty tissues growing in the scaffold, as we might expect in a normal valve,” said Tseng.

Additionally, researchers observed the degradation of the polymer to make way for new tissue with the help of gel permeability chromatography in ICL’s Molecular Sciences Research Hub’s Agilent Measurement Suite without affecting the valves performance.

Researchers will perform further animal studies to understand which processes are causing the polymer to degenerate and its link to tissue regeneration.

Furthmore, “there are various improvements to make on the manufacturing side,” added Tseng.

The data generated will be valuable when seeking regulatory approval for the first clinical trials, which are hoped to commence in the next five years.