Repairing the heart

Heart failure means that the heart does not pump blood around the body as well as it should. It usually occurs because the heart has become too weak or stiff over time, following damage to the heart muscle.

Currently, a heart transplant is the only option for end-stage heart failure, but because of a shortage of donor hearts, and because someone severely ill may not be able to withstand the lengthy surgery, this is only possible in a small number of cases. An exciting field of research has emerged, called regenerative medicine, in which researchers around the world are searching for ways to repair or regenerate damaged heart tissue. The prospect of being able to mend damaged heart muscle brings hope that one day, a heart transplant may no longer be necessary for anyone with heart failure.

What is regenerative medicine?

The body is made up of around 100 trillion cells, but they all grew out of one single cell – the newly fertilised egg. The heart, bones, skin, eyes and other cells were all generated from this single cell through a coordinated process of cell multiplication and specialisation. Most of the cells in the body have become highly specialised and will remain that way. But there are some cells that still have the ability to multiply and produce cells of a different type. These are stem cells.

Since the 1960s, researchers around the world have been working on the best ways to use stem cells to repair damaged tissues. In 1973 the BHF funded its first regenerative medicine research project led by Professor Donald Longmore at the National Heart Hospital in London, to look into how stem cells could help the repair of heart tissue damaged by a heart attack.

Mending Broken Hearts Appeal

But there have been, and still remain, significant obstacles to fulfilling the potential of regenerative medicine. That is why, in 2011, we launched the Mending Broken Hearts Appeal. This has now funded around £39 million of research into regenerative medicine across the UK, to find ways to mend diseased heart and blood vessels.

Thanks to the Mending Broken Hearts Appeal, in 2013 we funded three pioneering Centres of Regenerative Medicine led by Imperial College London and the Universities of Edinburgh and Oxford, working with other top UK universities to study how to regrow, repair or replace damaged or diseased hearts and blood vessels.

Professor Sian Harding’s team, from the Imperial College London-led Centre of Regenerative Medicine, has developed a 3D stem cell patch that can ‘beat’. The patches are designed to be attached to a damaged heart, physically supporting the damaged heart muscle and helping it pump more efficiently, while also releasing natural chemicals that stimulate the heart cells to repair and regenerate. Eventually, the aim is that the heart would incorporate the patch. Early studies have shown the patches are safe in animals and the team are now planning safety trials in humans.

Professor Ken Suzuki’s team at Queen Mary University London have developed a biodegradable ‘heart dressing’, containing stem cells, hormones and substances to stimulate the growth of new blood vessels and muscle cells after heart surgery. The dressing would be used at the same time as bypass surgery after a heart attack, to boost repair of the heart muscle. It has already shown promising results in the lab and could help to prevent heart failure after a heart attack.

These teams and others continue to develop their regenerative medicine research so that it can safely and effectively be used in humans. There is real hope that repairing the damaged heart using this technology can become a reality in the future.

First published 1st June 2021