A drug commonly used after transplant surgery could hold the key to limiting the damage suffered following a heart attack, new research has claimed.
The study concluded that temporarily decreasing a part of someone's immune system could be beneficial to them immediately after a heart attack.
Drugs like cyclosporin are used to do exactly that after a transplant, to stop the body rejecting a donated organ, and scientists believe they have found another use for it.
During a heart attack, a clot starves the heart of blood and can cause lasting damage. The heart is then damaged further by a mixture of chemicals and cells that rush in to the heart as blood flow is restored.
Currently doctors are unable to prevent or repair this damage and do not fully understand how the chemical build-up causes such severe damage.
The findings suggest that white blood cells are responsible for much of the damage, as they can become activated during a heart attack and travel in to the heart muscle.
Once inside the muscle tissue, they can release toxic chemicals that kill off parts of the heart. Normally these cells and their toxic chemicals would be used to fight infection.
Professor Ioakim Spyridopoulos, director of the Newcastle University Cardiovascular Research Centre, said: "Our research investigates exactly how we can target heart damage after a heart attack, and suggests drugs that could help.
"The beauty of this research is that we have used our new understanding of what happens inside the heart to help identify a potential drug that is already in use. If successful, heart attack patients could see the benefit of the study within a few years."
The study, which was funded by the British Heart Foundation and the Newcastle Biomedical Research Centre, conducted a study at the Freeman Hospital, Newcastle, where they studied 1,377 people for three years.
The patients who, after treatment to clear the blocked artery, lost the most white cells from their blood were almost five times more likely to die.
Professor Jeremy Pearson, associate medical director at the BHF, said: "This careful clinical investigation suggests that we could improve the outcome for the 500 people who go to hospital with a heart attack each day in the UK."
Someone has a heart attack in the UK every three minutes which can often lead to heart failure, which ultimately can be a fatal condition.