A scan normally used for cancer patients can identify if a person is on the verge of suffering a heart attack, it has been claimed.
It works by highlighting dangerous blockages in the heart before the condition worsens.
It is estimated that around 200 people die from heart conditions in the UK each day, many of which were caused by such blockages.
Researchers at Edinburgh University found that they could see where blockages are by tracking a chemical substance known as a radioactive tracer using a PET-CT scanner.
After being injected into a person's body, the tracer emits a glow that can be followed on the scanner.
Funded by the British Heart Foundation (BHF) and the Scottish Government, the study looked at 40 people who had previously suffered a heart attack and 40 at high risk due to having angina.
In 90 per cent of cases, those which had had a heart attack lit up at the location of the blockage which caused the condition.
A blockage was also highlighted in almost half of those with angina, suggesting they were very close to a heart attack.
Study leader Dr Mark Dweck, a BHF clinical lecturer and cardiologist, said: "We have developed what we hope is a way to “light up” plaques on the brink of rupturing and causing a heart attack.
"If we could know how close a person is to having a heart attack, we could step in with medication or surgery before the damage is done."
Professor Peter Weissberg, the BHF's medical director, said that the find may help to deal with the "ticking time bomb" heart attack presents in many people.
He added that research now needs to be carried out to confirm the findings and increase understanding on how the scans can be used in clinics to benefit those with cardiac conditions.