Scientists have developed special heart patches that could provide a lifeline for hundreds of thousands of people after suffering a heart attack.
The British Heart Foundation (BHF) said the patches, which are grown in a lab and help repair damaged hearts, could one day provide an off-the-shelf treatment for patients.
The thumb-sized patches of heart tissue contain up to 50 million human stem cells which are programmed to turn into working heart muscle cells that beat.
Experts say one or more patches could be implanted onto the heart of a heart attack victim to prevent or even reverse damage to the organ.
During a heart attack, the heart is starved of vital nutrients and oxygen, killing off parts of the heart muscle.
This weakens the heart and can eventually lead to heart failure, which affects an estimated 920,000 people in the UK.
Once sewn in place, the new patches are intended to physically support the damaged heart muscle and help it pump more efficiently.
Chemicals are also released that stimulate the heart cells to repair and regenerate.
Lab tests show that the patches start to beat spontaneously after three days and start to mimic mature heart tissue within one month.
In animals, the patches led to an improvement in the function of the heart after a heart attack, while blood vessels from the heart were able to grow into the patches.
Clinical trials on humans will now start in the next two years to make sure they work as powerfully in people.
The ultimate goal is to have a stock of pre-made patches that are compatible with all patients, so that a person suffering a heart attack could quickly have one implanted.
Dr Richard Jabbour, from the London BHF Centre of Regenerative Medicine, said: "One day, we hope to add heart patches to the treatments that doctors can routinely offer people after a heart attack.
"We could prescribe one of these patches alongside medicines for someone with heart failure, which you could take from a shelf and implant straight into a person."
Claire Marie Berouche, 52, from Ealing in west London, developed heart failure after a heart attack when she was just 45.
"I can't do the everyday normal things I used to do like popping to the shops or even just stay out late with friends," she said.
Research on the patches is being presented at the British Cardiovascular Society Conference in Manchester.
Australian Associated Press
