Also known as myocardial infarction, is the result of a blockage in the coronary artery . This can lead to the death of a segment of heart muscle. The person suddenly experiences severe pain in the centre of the chest. The pain extends to the throat and down the left arm. The person needs calm reassurance and emergency treatment. A person complaining of chest pain should never be left on their own and an ambulance should be called as soon as possible.