Patients are putting their lives at risk because they often do not recognise the symptoms of myocardial infarction (MI) and, consequently, do not present for treatment quickly enough, according to a study published in Heart (2000;84:137).
Ms W. S. Leslie (Glasgow Royal infirmary) and colleagues interviewed 313 patients who had survived an acute MI and found that, although 86 per cent of them had suffered chest pain, only 20 per cent had recognised this as being a symptom of MI. A quarter of the patients had made a call for medical help within one hour of the symptoms starting but, in 12 per cent of cases, the delay had exceeded 24 hours.
"In any healthy heart education programme, it is important that the serious nature of coronary symptoms is emphasised, along with the fact that they always warrant a call to the emergency ambulance service," Dr Leslie and colleagues say.
Most patients who had had more than one MI recognised their symptoms as being cardiac but 26 per cent of this group mistook the symptoms for those of angina. Many patients who had no previous cardiac history had "no idea" what had caused their symptoms or thought that they had indigestion, the authors say.
When asked why they had delayed calling for medical help, most patients responded that they had thought the symptoms "would go away" or that they had not been serious enough.
Most patients (55 per cent) called their general practitioner first rather than an ambulance because they did not think the symptoms were important enough to dial 999.
The authors say that mortality from acute MI can be reduced by 45 per cent if a thrombolytic is given within one hour of the onset of symptoms and by 25 per cent if given within three hours. "A delay in administration by 30 minutes reduces life expectancy by an average of one year," they say.
Commenting on the public's view of acute MI, they say that the perception that it is a dramatic event must be dispelled. Health care professionals should raise awareness of thrombolysis and the benefits of seeking medical attention promptly, they say.