Clopidogrel on its own is recommended for use in England

Oxford University researchers looked at the effect of adding the anti-clotting drug clopidogrel to aspirin, which is often given to heart attack victims.

A study of 45,800 patients in China found adding clopidogrel cut the risk of deaths, repeat heart attacks and stroke by 9%, the Lancet reported.

Heart experts said the study showed the treatment was "safe and effective".

The treatment also led to a 7% reduction in deaths alone, compared with patients who were given a dummy drug in addition to aspirin.

Researchers said there was no apparent increase in life-threatening bleeding, which can be a hazard with blood-thinning drugs.

This study confirms that it is safe and effective also in heart attacks Professor Jeremy Pearson, of the British Heart Foundation

Lead researcher Dr Zhengmin Chen: "If early clopidogrel therapy was given in hospital to just one million of the 10 million patients who have a heart attack every year, then it would, on present evidence, prevent about 5,000 deaths and 5,000 non-fatal heart attacks and strokes.

"Moreover, continued treatment with clopidogrel after hospital discharge could lead to further net gains, although the benefits and hazards of more long-term therapy are still under investigation."

In England, clopidogrel is only recommended for heart attack patients when it is used on its own.

A second part of the study looked at the effect of giving patients early treatment with the beta-blocker drug metoprolol.

Risk

The drug cut the relative risk of repeat heart attacks and dangerous heart rhythms by about 15% to 20%.

But at the same time it increased the risk of cardiac shock by 30%, especially during the first day or so after admission.

Professor Jeremy Pearson, associate medical director of the British Heart Foundation, said: "This is the most recent of several studies that have shown that clopidogrel has benefits for patients with vascular disease.

"Its use is already well established for patients with unstable angina and this study confirms that it is safe and effective also in heart attacks."

But he said the study on metoprolol showed that such drugs should be used with caution in the early hours of an attack.

Meanwhile, the Lancet also reported that waist-to-hip ratio is a better obesity measure for assessing the risk of a heart attack than body mass index (BMI).