A heart attack is known as a myocardial infarction or coronary thrombosis and is caused when part of the heart muscle is starved of oxygen and dies.

Heart attacks typically occur when a blood clot forms in one of the blood vessels (known as coronary arteries) leading to the heart muscle. Symptoms include crushing pain in the centre of the chest which may travel to the arms, ears, neck, jaw or wrists.

In this video, a cardiologist explains a heart attack, the treatments available and why people with coronary heart disease should reduce their risk factors.