The British "stiff upper lip" may explain why 40 per cent of people would not call an ambulance immediately if they thought they had suffered a heart attack, according to a survey released yesterday.

The YouGov poll also revealed 64 per cent of people experiencing heart attack symptoms would ring their partner, friend, relative, doctor or a telephone health service rather than call an ambulance.

"These statistics portray a very worrying, and perhaps very British, reluctance to call 999 (the British emergency phone number) even in the most serious of emergencies," said Professor Peter Weissberg, medical director of the British Heart Foundation (BHF) which commissioned the poll.

"Maybe it is our natural reserve and stoicism, but it is costing lives," added Weissberg. "Every second counts when you are having a heart attack, and the quicker you call 999 the greater your chances of survival."

The BHF Monday launched a "Doubt Kills" campaign, encouraging people to dial 999 if they suspected they had had a heart attack.

The BHF said people experiencing symptoms of a heart attack waited on average 90 minutes before calling an ambulance, and an average of two hours and 40 minutes passes before they are treated.

Those who receive treatment four to six hours after the onset of heart attack symptoms are twice as likely to die as those treated within one to two hours.

Weissberg said sometimes people mistook the pain of a heart attack for indigestion.

"Central chest pain is the most common warning sign," he said. "But it does not have to be excruciating to be a serious problem.

"Someone suffers a heart attack every 2 minutes in the UK, and about one in three dies before reaching hospital."