Angina is a dangerous condition causing acute chest pains that can prove fatal if left unchecked. Robert Mair investigates.

Angina Pectoris (more commonly known as angina) refers to chest pain caused by a lack of blood (and consequently oxygen) to the heart muscle. It is usually the result of a hardening or narrowing in the coronary arteries which supply the heart with blood, and is brought on by either physical activity or emotional upset.

The symptoms of an attack vary wildly between sufferers, but with medication it can be brought under control.

The causes

Coronary arteries deliver oxygen-rich blood to the heart. There are two coronary arteries – the left and the right – and these divide numerous times, ensuring oxygen gets to all parts of the heart’s wall.

However, these arteries can become narrowed by a build-up of fat within the walls. Over time, these fatty deposits increase until the artery can no longer supply the heart with enough oxygen-rich blood. This may be especially noticeable when the heart requires more oxygen than normal; for example, during physical activity. This can result in pain or discomfort – which is known as angina.

This clogging of the arteries is called atherosclerosis and is itself an inflammatory disease brought on by furring or hardening of the arteries. Consequently there is a need to keep the arteries healthy to prevent atherosclerosis and angina.

Atherosclerosis, and subsequently angina, is likely to develop because of the following:

  • Diabetes
  • Tobacco smoke
  • High blood pressure
  • High blood cholesterol level
  • Being overweight

It can also occur if your family has a history of heart attacks, and is more frequent in people over the age of 55.

1 in 12 men and 1 in 30 women in England between the age of 55 and 64 have angina. That figure rises in over 65’s. It’s thought that the prevalence of angina in men is because historically more men smoked than women.

Spotting the symptoms

Due to the nature of chest pains, angina is often confused with a heart attack and can also be mistaken for muscular pain, indigestion or anaemia. But there are a number of differences between angina and similar conditions.

For example, a heart attack is caused by a blood clot. This clot blocks a narrowed coronary artery causing severe chest pain – usually far more intense than the pain caused by angina. The pain will last longer and will not subside with rest and you may sweat and feel nauseous.

However, Angina may result in more of an uncomfortable feeling in the chest, ranging from a dull ache to severe tightness. The pain can spread to the arms, back, stomach, neck and jaw. Symptoms usually fade within 10 to 15 minutes.

An attack of angina can be triggered due to a certain set of circumstances, which can all bring on an attack. These include:

  • Physical activity
  • Emotional distress
  • Walking – particularly if you’re walking after a meal

However, it can also come on while you rest or when you are asleep.

Types of angina

There are two types of angina – stable and unstable. These labels apply to the condition of the angina, and can be used to describe the seriousness of the condition.

Stable angina symptoms develop gradually and intermittently, generally during physical activity. Pain may pass quickly once the activity has stopped, and the condition can easily be controlled by drugs.

Unstable angina can come on at any time. It is not linked to physical activity and may strike when at rest. It is also different to stable angina due to the physical impact the condition has on the coronary arteries. It can cause the fibrous cap covering the fatty materials behind atherosclerosis to rupture, increasing the likelihood of blood clots – and subsequently heart-attacks – occurring.

Diagnosis

Doctors will use a variety of scans to diagnose angina and rule out any other problems. These include:

  • An electrocardiogram (ECG) or an exercise ECG. This records the rhythm and electrical activity of the heart. But as angina often occurs during periods of activity, an exercise ECG may be carried out. This may involve riding an exercise bike or walking on a treadmill and will get a far truer reading than a normal ECG carried out at rest.
  • A stress echocardiogram. This gives the doctor a full view of the heart by using echo pulses (based on the same principle that bats use to find their way around in the dark). A stress echocardiogram is carried out after the heart has done some work, but is a longer process than an ECG.
  • A radioisotope scan. Some people with angina are unable to exercise, meaning a radioisotope scan may be used. radioactive material is injected into the blood, and doctors will use gamma rays to track the movement of it. This will show them the areas of the heart that do not receive sufficient oxygen.
  • A coronary angiogram. This is an X-ray of the blood vessels, carried out by using a catheter. A dye will be injected into the coronary arteries, and X-rays taken from numerous angles. This will show where the arteries have narrowed.

Treatment

Angina treatment aims to relieve the symptoms and slow the progression of the disease. Treatments for angina include:

  • Aspirin. An aspirin a day is particularly beneficial to people with stable angina as it prevents the blood from clotting and keeps it ‘thin’.
  • Beta blockers. These have been found to have a major impact on angina as they make attacks less frequent. They work by slowing down the heart and making it do less work. This in turn reduces how much oxygen it uses. Beta blockers also lower blood pressure, and are one of the first treatments offered to angina sufferers.
  • Calcium channel blockers. The aim of calcium channel blockers is to widen the arteries, allowing more oxygenated blood to pass through to the heart. They are often administered alongside beta blockers.
  • Nitrates. These open up the blood vessels and widen the coronary arteries. Nitrates come in both tablet and spray form, but lose their strength quickly so will need to be replaced every eight weeks.
  • Exercise. Although angina is aggravated by physical activity, this is generally where exercise is absent from daily routine. Regular gentle exercise over a long period of time is hugely beneficial as it develops the health and fitness of the heart (and rest of the body, including keeping the weight down) providing resilience against conditions like angina.

If angina is life-threatening, surgery is a possibility. Two options are available – a coronary angioplasty and coronary bypass surgery. An angioplasty is where a catheter is inserted into the artery and the narrowed area is widened using a balloon. Wire meshing called a stent will then keep the artery in its widened position – allowing blood to pass through freely.

Coronary bypass surgery is where the narrowed part of the artery is bypassed by grafting a blood vessel between the aorta (the main artery that leaves the heart) and a point past the blockage. It is a major operation and will require a week in hospital.

Prevention is better than cure

You can reduce your risk of developing angina or complications by following a healthy lifestyle i.e.

  • Not smoking
  • Taking regular exercise
  • Balanced healthy diet
  • Maintaining a healthy body weight