A heart attack is caused by a sudden obstruction of the blood supply to a section of heart muscle. It is usually caused by a blood clot (thrombus), which leads to a blockage in a coronary artery.

A heart attack can also be called a myocardial infarction or coronary thrombosis. The effects of a heart attack depend on how much of the heart muscle is affected.

Aspirin can be used to try to limit the damage to the heart muscle. It works by reducing the ‘stickiness’ of the blood platelets and prevents more of them sticking onto the clot already present and prevents the clot from expanding. 

It is important for a first aider to be able to recognise the signs and symptoms of a potential heart attack. Early advanced medical help is vital in order to preserve heart muscle. 

Recognition of a heart attack

• Persistent central chest pain – the most important feature in the history – caused by a cut off of the blood supply to the heart muscle and consequent deprivation of oxygen.
• The pain often spreads to the jaw and down one or both arms.
• The pain is not relieved by rest – unlike narrowing in angina, a heart attack is caused by a blockage in the artery.
• Pallor, sweating and nausea – they are all signs of nervous stimulation as a result of the pain.
• Breathlessness and anxiety – as a result of the pain.
• A rapid weak or irregular pulse.
• Gasping for air (“air hunger”)
• Ashen skin colour and blueness around the lips (cyanosis).
• Sudden collapse or unconsciousness
• A feeling of impending doom – “I feel like I’m going to die”

Sometimes the pain is not central but may be in the jaw or feel to the casualty like indigestion. Sometimes there little pain but the other indicators are present. In both these situations err on the side of caution and deal with the casualty as if having a heart attack.