A heart attack, or myocardial infarction, occurs when the flow of the blood to the heart is suddenly blocked, usually by a blood clot. 

It can be easy to dismiss its early signs, as many medical conditions can mimic a heart attack, however, it is never too early to call 999 and describe your symptoms.

The faster you act, the better the chances of a positive outcome. A heart attack is a serious medical emergency and can be life-threatening.

Check out our latest infographic on heart attacks, where we explain in more detail the causes, most common warning signs and prevention.