A heart attack is said to have occurred when a clot of blood suddenly blocks a coronary artery, one of the main blood vessels to the heart muscle, the myocardium. When this happens, the affected part of muscle will die because of the resulting lack of oxygen, causing the casualty severe, and gripping chest pain.
Sometimes, the casualty may have a history of angina pectoris, a condition in which the coronary arteries are narrowed because of the build-up of fatty deposits on the inside walls. This restricts the blood flow to the myocardium and causes severe crushing pain in the chest, not unlike that of a heart attack.
It is sometimes, therefore, very difficult to distinguish between an attack of angina and a heart attack. Unlike a heart attack, angina is usually relieved by rest or by placing a tablet of glycerin reinitiate (GTN) under the casualty's tongue.
Signs and symptoms of heart attack
1. Severe crushing chest pain, possibly radiating down one or both arms, or up into the jaw. The pain will not be relieved by rest or the administration of GTN.
2. Facial pallor or 'ashen' appearance, sometimes with bluefish coloring of the lips.
3. The skin may be cold and clammy to the touch and the casualty may be sweating profusely.
4. The casualty may suffer from breathlessness, weakness and dizziness.
5. Nausea and vomiting may be present.
6. The pulse may be irregular and either slow or fast.
7. The casualty may appear profoundly anxious.
8. The casualty may collapse suddenly, possibly without warning.
Treatment of a heart attack
1. Keep the casualty as calm and as comfortable as possible. Loosen any tight clothing and place pillows behind the head and knees to support him or her in a half-sitting position.
2. Phone 999 for an ambulance (or ask somebody to do this for you so that you can remain with the casualty). Be prepared to resuscitate.
3. If ordinary aspirin tablets are available, give the casualty one and ask him or her to chew and swallow it. Recent research has shown that aspirin given immediately after the onset of heart attack can improve the victim's chances of recovery, perhaps by inhibiting further clotting in the coronary arteries.