I would welcome the introduction of a new clot buster that is effective and so quick and easy to use

Professor Jennifer Adgey

More than half the people who have a heart attack currently die before they even reach a hospital.

It is hoped the new drug will improve survival chances greatly.

Because TNK does not need to be stored in a fridge, it can be kept in an ambulance or a doctor's bags and administered immediately.

Professor Jennifer Adgey, Consultant Cardiologist at the Royal Victoria Hospital, in Belfast, said the new drug could save many lives.

'Quick and easy'

She said: "If 'clot busting' therapy is administered within the first hour of the onset of symptoms of a heart attack, 65 lives per 1,000 can be saved.

"Therefore, I would welcome the introduction of a new clot buster that is effective and so quick and easy to use."

The government has already recognised the importance of speed in preventing deaths due to heart attacks.

And it has promised, through the National Service Framework guidelines for CHD, to ensure that three in four eligible heart attack victims receive life-saving, "clot busting" drugs - thrombolysis - within 30 minutes of arrival at hospital.