The medical term for a heart attack is myocardial infarction or MI. A heart attack is usually caused by coronary heart disease (CHD). One of the patches of fatty deposits in the coronary artery ruptures causing a blood clot to form which cuts off the blood supply to the heart muscle. This starves the heart muscle of oxygen which may cause permanent damage. The clot can cause a partial blockage (NSTEMI) or total blockage (STEMI) of the coronary artery.

In rarer cases, a heart attack can be caused by other conditions such as spontaneous coronary artery dissection (SCAD) where the lining of one of the arteries supplying the heart splits, affecting the blood supply to the heart muscle.


Symptoms of heart attack vary from person to person but may include:

  • chest pain which may radiate from the chest to the jaw, neck, arms and back
  • shortness of breath
  • feeling weak or lightheaded, or both
  • an overwhelming feeling of anxiety


A heart attack is a serious medical emergency and an ambulance should be called immediately.


Tests for heart attack usually include:

  • an electrocardiogram (ECG)
  • a blood test for an enzyme called troponin
  • angiography of the coronary arteries


A heart attack is treated by restoring blood flow through the blocked artery, as soon as possible, to minimise damage to the heart muscle and includes:

  • angioplasty to reopen the blocked coronary artery and the insertion of stents – this procedure is also called percutaneous coronary intervention (PCI) and is the most common treatment for a heart attack
  • coronary artery bypass surgery (CABG) using a blood vessel taken from the leg, arm or chest, to get around the blockage
  • treatment with a ‘clot-busting’ drug to dissolve the blood clot

Relevant Research

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