Angina

Written by: 
Michelle Roberts, medical writer

Angina is discomfort or pain in the chest, not dissimilar to indigestionDiscomfort after eating.. It occurs when the heart muscleTissue made up of cells that can contract to bring about movement. is temporarily deprived of sufficient oxygen by reduced bloodA fluid that transports oxygen and other substances through the body, made up of blood cells suspended in a liquid. flow, known as myocardial ischaemiaInadequate flow of blood to the heart muscle..

The main points of interest and concern are:

What are the symptoms of angina?

Angina symptoms vary depending on the severity of the attack. People with mild anginaA central chest pain caused by insufficient oxygen supply to the heart. may have such mild discomfort that they assume it is of no importance.

A severe anginaA central chest pain caused by insufficient oxygen supply to the heart. attack can cause chest pain that spreads to the neck and throat, jaw, one or both arms, upper abdomenThe part of the body that contains the stomach, intestines, liver, gallbladder and other organs. and, more rarely, the area between the shoulder blades.

This may be accompanied by breathlessness or a choking feeling, sweating, nausea and anxiety.

What causes angina?

Angina is usually caused by coronaryRelating to the arteries supplying the heart itself. arteryA blood vessel that carries blood away from the heart. Apart from the pulmonary artery and umbilical artery, all arteries carry oxygenated blood. disease, a form of cardiovascular disease in which when the arteries supplying the heart (the coronaryRelating to the arteries supplying the heart itself. arteries) become progressively narrowed.

Fatty deposits (called plaques or atheromaThe formation of fatty deposits in the arteries, which limit blood flow.) accumulate inside the lining of the coronaryRelating to the arteries supplying the heart itself. arteries, impeding the supply of bloodA fluid that transports oxygen and other substances through the body, made up of blood cells suspended in a liquid., oxygen and nutrients to the heart.

This is often part of a body-wide problem of arterial narrowing known as atherosclerosisDisease leading to fatty deposits in the inner walls of the arteries, which reduce and may eventually obstruct blood flow., which is largely linked to dietary and lifestyle factors.

Heart disease is the leading cause of death globally[1], so anginaA central chest pain caused by insufficient oxygen supply to the heart. is exceedingly common. It is most frequent among populations that have higher incomes, although the incidenceThe number of new episodes of a condition arising in a certain group of people over a specified period of time. is high even in low-income countries.

Smoking, high bloodA fluid that transports oxygen and other substances through the body, made up of blood cells suspended in a liquid. pressure, high cholesterolA substance present in many tissues and an important constituent of cell membranes although high concentrations of a certain type of cholesterol in the blood are unhealthy. and diabetes are known risk factors that damage the coronaryRelating to the arteries supplying the heart itself. arteries.

Taking too little exercise, being overweight or obese, or having a family history of heart attacks make anginaA central chest pain caused by insufficient oxygen supply to the heart. more likely.

Angina can be aggravated by other conditions, including:

  • Anaemia
  • Fast or abnormal heart rhythms
  • Heart valveA structure that allows fluid to flow in one direction only, preventing backflow. disease
  • Thickening of the heart muscleTissue made up of cells that can contract to bring about movement., known as hypertrophyAn increase in the size of a tissue of organ resulting from an increase in the size of its individual cells..

It can also be triggered by stressRelating to injury or concern. (including emotional stressRelating to injury or concern.), cold weather, alcohol or a large meal.

What are the different types of angina?

Stable anginaA central chest pain caused by insufficient oxygen supply to the heart. is the most common type and has a regular, predictable pattern. The pain is usually brought on by exertion and goes away in a few minutes when the person rests or takes anginaA central chest pain caused by insufficient oxygen supply to the heart. medicine.

Unstable anginaA central chest pain caused by insufficient oxygen supply to the heart. follows an unpredictable pattern and that may be more severe or prolonged, not relieved by rest or anginaA central chest pain caused by insufficient oxygen supply to the heart. medication. It can be brought on by minimal exercise or may occur at rest, for example when lying in bed at night. It is a medical emergency and requires immediate hospital admission because of the high risk of heart attackThe death of a section of heart muscle caused by an interruption in its blood supply. Also called a myocardial infarction. (myocardial infarctionDeath of an area of heart muscle due to poor blood supply.).

One rare type of unstable anginaChest pain caused by poor blood supply to the heart that comes on unpredictably - not just during exercise. is called variant or Prinzmetal's anginaA central chest pain caused by insufficient oxygen supply to the heart. and is usually due to spasm of the coronaryRelating to the arteries supplying the heart itself. arteryA blood vessel that carries blood away from the heart. Apart from the pulmonary artery and umbilical artery, all arteries carry oxygenated blood., rather than narrowing. It occurs without any warning, often during the night or while at rest.

If you develop any sudden or severe pain in your chest it is important to seek urgent medical help.

How is angina diagnosed?

Doctors diagnose anginaA central chest pain caused by insufficient oxygen supply to the heart. based on symptoms, a basic examination and bloodA fluid that transports oxygen and other substances through the body, made up of blood cells suspended in a liquid. tests, as well as the results of targeted medical tests, including a trace of the electrical activity of the heart, called an electrocardiogramA tracing of the electrical activity of the heart. (ECGAbbreviation for electrocardiogram, a tracing of the electrical activity of the heart to help in the diagnosis of heart disease.). Doctors may also want to do an ECGAbbreviation for electrocardiogram, a tracing of the electrical activity of the heart to help in the diagnosis of heart disease. while you exercise on a treadmill or an exercise bike. This is called a stressRelating to injury or concern. test or exercise tolerance test.

A coronary angiogramAn X-ray image of the coronary arteries, which is taken after introducing a catheter through a blood vessel and threading it towards the heart, then injecting a contrast medium to improve visibility. may be needed to examine the heart's arteries in detail, or an echocardiogramAn ultrasound examination of the heart as it is pumping. Also known as an 'echo'. may be carried out to look at the heart's chambers and valves.

The results will help distinguish anginaA central chest pain caused by insufficient oxygen supply to the heart. from other possible diagnoses, including backflow of the stomach's acidic contents into the oesophagusThe gullet, the part of the gastrointestinal system that extends down from the mouth cavity to the stomach. (gastro-oesophageal reflux) or a heart attackThe death of a section of heart muscle caused by an interruption in its blood supply. Also called a myocardial infarction. (myocardial infarctionDeath of an area of heart muscle due to poor blood supply.).

A decision can then be taken about the most suitable treatment.

Any sudden or severe chest pain needs emergency medical evaluation.

How is angina treated?

For immediate pain relief, a medication called glyceryl trinitrate (GTN) opens up the coronaryRelating to the arteries supplying the heart itself. arteries, improving bloodA fluid that transports oxygen and other substances through the body, made up of blood cells suspended in a liquid. supply to the heart muscleTissue made up of cells that can contract to bring about movement. within minutes. People with anginaA central chest pain caused by insufficient oxygen supply to the heart. are advised to carry glyceryl trinitrate as a spray or tablets with them at all times.

For long-term symptom prevention, there are four main classes of drugs that can be prescribed alone or in combination:

  • Beta-blockers - these make the heart beat slower and with less force
  • Long-acting nitrates - these open up the coronaryRelating to the arteries supplying the heart itself. arteries to improve bloodA fluid that transports oxygen and other substances through the body, made up of blood cells suspended in a liquid. supply to the heart muscleTissue made up of cells that can contract to bring about movement.
  • Calcium-channel blockers - these have the same effect as nitrates
  • Potassium channel activators - these act in the same way as nitrates.

To prevent or delay coronaryRelating to the arteries supplying the heart itself. arteryA blood vessel that carries blood away from the heart. Apart from the pulmonary artery and umbilical artery, all arteries carry oxygenated blood. disease, doctors can prescribe statinOne of a class of drugs that inhibit cholesterol formation in the liver. drugs to lower cholesterolA substance present in many tissues and an important constituent of cell membranes although high concentrations of a certain type of cholesterol in the blood are unhealthy. and anti-plateletStructure in the blood that helps the blood to clot. drugs, such as aspirin, that make the bloodA fluid that transports oxygen and other substances through the body, made up of blood cells suspended in a liquid. less sticky.

When medicines do not work or the disease is more serious, doctors may recommend surgery.

Angioplasty can be used to widen narrowed arteries or a coronaryRelating to the arteries supplying the heart itself. arteryA blood vessel that carries blood away from the heart. Apart from the pulmonary artery and umbilical artery, all arteries carry oxygenated blood. bypass graft (CABG) operation can be performed to bypass one or more blocked arteries.

What complications of angina are there?

If you have anginaA central chest pain caused by insufficient oxygen supply to the heart. you have a higher than average risk of heart attackThe death of a section of heart muscle caused by an interruption in its blood supply. Also called a myocardial infarction. (myocardial infarctionDeath of an area of heart muscle due to poor blood supply.), although this risk can be reduced by taking medication such as aspirin and a statinOne of a class of drugs that inhibit cholesterol formation in the liver..

As the coronaryRelating to the arteries supplying the heart itself. arteries become more diseased, the bloodA fluid that transports oxygen and other substances through the body, made up of blood cells suspended in a liquid. flow to the heart becomes increasingly compromised and this can lead to acute coronary syndromeA range of clinical conditions caused by coronary artery disease: it encompasses the full spectrum from unstable angina to heart attack.. In acute coronary syndromeA range of clinical conditions caused by coronary artery disease: it encompasses the full spectrum from unstable angina to heart attack. the bloodA fluid that transports oxygen and other substances through the body, made up of blood cells suspended in a liquid. flow to the heart becomes suddenly interrupted, culminating in unstable anginaChest pain caused by poor blood supply to the heart that comes on unpredictably - not just during exercise. or a heart attack.

When a heart attackThe death of a section of heart muscle caused by an interruption in its blood supply. Also called a myocardial infarction. occurs, bloodA fluid that transports oxygen and other substances through the body, made up of blood cells suspended in a liquid. can no longer reach the heart muscleTissue made up of cells that can contract to bring about movement. and the part affected dies.

If you suspect a heart attackThe death of a section of heart muscle caused by an interruption in its blood supply. Also called a myocardial infarction. it is important to seek medical help at once.

Living with angina

Making healthy lifestyle choices helps to reduce your risk of anginaA central chest pain caused by insufficient oxygen supply to the heart.. These include:

  • Eating a healthy, low-fatOne of the three main food constituents (with carbohydrate and protein), and the main form in which energy is stored in the body. diet
  • Taking regular exercise
  • Quitting smoking.

Finding ways to cope with stressRelating to injury or concern. is also beneficial.

It is important for people with anginaA central chest pain caused by insufficient oxygen supply to the heart. to learn what triggers their attacks and to take steps to avoid these triggers where possible.

Although exertion can trigger anginaA central chest pain caused by insufficient oxygen supply to the heart., it is important to keep active as regular activity reduces the risk of coronaryRelating to the arteries supplying the heart itself. arteryA blood vessel that carries blood away from the heart. Apart from the pulmonary artery and umbilical artery, all arteries carry oxygenated blood. disease progressing. So if you have anginaA central chest pain caused by insufficient oxygen supply to the heart., you can still exercise as long as you pace yourself. The same applies to sexual intercourse.

Many people with anginaA central chest pain caused by insufficient oxygen supply to the heart. carry on working, although some people cannot continue in their occupation for safety reasons. Examples include pilots, divers and people with jobs that are highly demanding physically or mentally.

It is important for people with anginaA central chest pain caused by insufficient oxygen supply to the heart. to learn how to manage their condition, know which medicines they need and learn when they need to seek medical help.

It is important to see a doctor urgently if:

  • You are getting anginaA central chest pain caused by insufficient oxygen supply to the heart. for the first time
  • You have anginaA central chest pain caused by insufficient oxygen supply to the heart. and the condition is getting worse and occurring more frequently
  • You have anginaA central chest pain caused by insufficient oxygen supply to the heart. and your anginaA central chest pain caused by insufficient oxygen supply to the heart. occurs when you are at rest.

People with anginaA central chest pain caused by insufficient oxygen supply to the heart. are also advised to have a fluA viral infection affecting the respiratory system. jab each year.

References: 
  1. 'The top 10 causes of death'. World Health Organization. Link