SCIENTISTS in Scotland have discovered a life-saving technique which can identify people who are about to suffer a heart attack.

The test, developed at Edinburgh University, uses a radio-active tracer which is injected into patients' veins.

They are then given a scan and fatty plaques in the arteries supplying the heart with blood and which are in danger of rupturing - and causing a heart attack - light up.

The technique means patients on the brink of a heart attack or stroke can be treated aggressively with drugs or surgery in a bid to save them.

It is the first time a technique has been found to establish those people at highest risk. The test's research trial was published in The Lancet today.

The study, funded by the British Heart Foundation and the Scottish Government's Chief Scientist Office, looked at two groups of patients. Forty had just had a heart attack and 40 suffered from angina and were at risk of having one.

More than 90% of those in the first group had a lit-up area in one of their blood vessels, corresponding exactly to the location of the plaque that caused their heart attack.

About 40% of patients with angina also had a plaque that lit up, as well as high-risk features suggesting a heart attack may be imminent, and treatment would be required.

Both the tracer and the PET-CT scan used in the test are already widely available in hospitals. The former has been used in bone imaging for several decades, while the latter is commonly used in cancer diagnosis.

"We have shown for the first time that high risk fatty plaques - on the verge of potentially causing a heart attack - can be detected on a PET-CT scan in the arteries supplying the heart with blood," said Dr Nikhil Joshi, of Edinburgh University.

"If we are now able to identify patients at highest risk of having a heart attack, we could possibly take steps to prevent this catastrophic event. This could fundamentally change the way we approach and manage these patients, reducing their risk of a future heart attack."

Professor Andrew Morris, Scotland's chief scientist, said: "Heart disease has been a clinical priority for NHS Scotland for more than 15 years and data show that deaths from this condition are falling, however there is still room to improve the diagnosis and treatment.

"These are exciting data - being able to prospectively identify patients at the highest risk of a heart attack and provide treatment to prevent this would be a significant step forward in the clinical management of this group. It is important therefore that these findings are further tested to determine their best clinical use."

Professor Peter Weissberg, medical director at the British Heart Foundation, said: "Being able to identify dangerous fatty plaques likely to cause a heart attack is something that conventional heart tests can't do.

"This research suggests that PET-CT scanning may provide an answer - identifying 'ticking time bomb' patients at risk of a heart attack.

"We now need to confirm these findings, then understand how best to use new tests like this to benefit heart patients."

Figures published earlier this year showed Glasgow remains Scotland's heart disease capital. From 2009-2011 the city had 128 deaths per 100,000 people, the third highest rate in the UK.

The UK's highest number of heart deaths was in Tameside in Greater Manchester, followed by Ballymoney in Northern Ireland.