In most surveys coronary heart disease or CHD is named as Britain's biggest killer. It develops when blood flow becomes restricted to the heart through the build up of fatty deposits on the walls of the coronary arteries. These are the main arteries that carry blood to the heart.

The heart is a fist sized muscle that pumps blood around the body; but as it is a muscle it needs its own blood supply too. Heart disease occurs when these specialist departments that feed the heart become clogged and in the worse case scenario, blocked.

The first stage of CHD happens when the inner linings of these coronary arteries gradually become furred with a thick, sludgy porridge of substances known as plaque, Plaque is made from cholesterol. This process of clogging up is known as arteriosclerosis.

These plaques begin to narrow the space through which blood can pass. They also have the knock-on effect of blocking the supply of nutrients to the arms which makes them lose their elasticity. They also cause high blood pressure; This extra strain on the heart as it attempts to pump the same volume of blood through a restricted passage can also lead to heart disease.

To make matters worse, arteriosclerosis occurs in all of our arteries, further increasing blood pressure and increasing the strain on the heart.

The first sign of a struggling heart is angina. These sever chest pains are a sign of a heart trying to keep beating on a restricted supply of oxygen.

Although some factors contributing to CHD are genetic, most are lifestyle related. Poor nutrition, lack of exercise, diabetes, high blood pressure and most of all smoking are the main culprits.

So what actually is a heart attack?
When one of the arteries that supply blood to the heart (coronary arteries) becomes completely blocked then you are in trouble. This full blockage is often caused by a section of plaque cracking or splitting open. The already narrowed artery now forms a blood clot (just like any wound) which then completely blocks it.

As it is no longer receiving any oxygen, the part of the heart that was supplied by that particular artery begins to die. Emergency medical treatment is now needed to unblock the artery and restore the blood flow top that bit of the heart. This can be done either through blood thinning drugs that will help to dissolve the arterial blockage (known as a clot or thrombus) or via a small operation that will physically remove the clot. This is done by threading small instruments up the arms (usually through the inner thigh).

The seriousness of a heart attack depends very much on the amount of muscle that dies before the condition is treated. If only a small area is affected then there is a higher chance of recovery and less risk of death.

Although a heart attack will always cause some permanent damage, most of the heart will be able to recover provided that the blood supply is not interrupted for too long.

What are the signs of a heart attack?
The symptoms to look out for are: a shortness of breath, a tightness in the chest. This is said to feel like a heavy weight or a squeezing.

There can also be pain traveling outwards from the chest, to the arms, neck and jaw.

You may feel sick or be physically sick.

A panic attack or sharp feeling of anxiety.

Light headedness

Coughing or wheezing.

If any of these symptoms are present, then call emergency!