Heart & Stroke Conditions Explained

Definition

Atrial Fibrillation

Atrial Fibrillation, also known as A Fib or AF is the most common arrhythmia.

An arrhythmia is an abnormal heart beat which is continuously irregular with no pattern to it at all.

It can affect adults of any age but is more common as you get older. It is estimated to affect at least 1% of the population at the age of 60 years and 5% at the age of 70 years. It occurs more frequently in those with underlying heart disease.

With atrial fibrillation your heart beats in a disorganised and irregular way which can lead to a range of symptoms and potential complications. While it is not immediately life-threatening in the same way as some arrhythmias, it can lead to heart failure or stroke and so it has potentially serious effects.

During atrial fibrillation, the normal regular rhythmic activity of the upper chambers or atria is replaced by chaotic irregular activity. This leads to an irregular and usually fast pulse rate which may cause palpitations and congestion of the lungs.

Also, because the upper chambers no longer contract and relax in the normal way, there may be pooling of the blood which can lead to blood clot formation. If a piece breaks off, it can travel in the blood stream and block a small artery somewhere downstream.

The most serious situation is when a clot lodges in an artery in the brain as this can cause a stroke.

 

Related topics: heart failure, stroke, palpitations, coronary heart disease, high blood pressure, ECG, exercise.

Symptoms

Atrial Fibrillation

Some people have no symptoms and are only diagnosed at a routine check-up with their doctor.

Or it may only be diagnosed when they present with complications. Other people feel their irregular heartbeat straight away through a range of symptoms such as:

  • Palpitations
  • Tiredness or weakness
  • Difficulty exercising
  • Dizziness, light-headedness or fainting
  • Chest pain
  • Discomfort or difficulty breathing
  • Shortness of breath

 

There are three types of atrial fibrillation:

1. Paroxysmal atrial fibrillation

These episodes usually last a few minutes to hours or days. The episodes come and go on their own, and do not usually last longer than one week. If you have symptoms they may also come and go.

 

2. Persistent atrial fibrillation

These episodes last longer than one week and do not go away on their own. You will need medical treatment to bring back your normal regular rhythm.

 

3. Permanent atrial fibrillation

Your irregular heartbeat does not return to normal rhythm and medical treatment cannot return the heart to normal rhythm. You may require medications to control the heart rate.

 

It is important for you to know which type of atrial fibrillation you have so that you can understand your condition and learn how to manage it. However, the type of atrial fibrillation you have is not fixed. If you have paroxysmal or persistent atrial fibrillation this can become a permanent type over time.

Causes

Atrial Fibrillation

The causes of atrial fibrillation are not always clear but your chances of developing atrial fibrillation can go up if you have one or more medical conditions.

These include high blood pressure, diabetes and heart disease. However, in many patients no underlying cause is found.

The risk factors that mean you are more likely to develop atrial fibrillation include:

 

  • Age, especially if you are over 65
  • Coronary heart disease, previous heart attack
  • Disease of heart valves
  • Heart failure
  • High blood pressure
  • Overactive thyroid gland
  • Heart defects you’re born with (congenital)
  • Lung infections, such as pneumonia
  • Pulmonary embolism (blood clots)
  • Heart or lung surgery
  • Exposure to stimulants, such as medications, caffeine, tobacco or alcohol abuse*

 

* Alcohol abuse, such as drinking large amounts of alcohol over a long time, is a major factor in people developing atrial fibrillation. Even young people can get atrial fibrillation after binge-drinking occasions.

Prevention

Atrial Fibrillation

Although atrial fibrillation is not generally life-threatening; it is a serious condition and can lead to you getting serious complications such as other heart problems and stroke.

By knowing about the possible complications and working closely with your doctor, you can find out how to lower your chances of them happening to you.

There are some changes you can make to your lifestyle that may help you with your atrial fibrillation:

 

  • Be active. Check with your doctor or nurse what a safe and reasonable level of activity or exercise is for you before you start.
  • Ask your doctor, nurse or pharmacist for advice on what types of food to eat. You should do this especially if you take certain anticoagulant tablets, as some food and drink can affect the way your tablets work.
  • Avoid stimulants such as caffeine, like in coffee, alcohol, and nicotine from smoking. These can trigger an irregular heart rate.
  • Have your blood pressure and cholesterol monitored regularly, and keep them under control.
  • Reduce stress and find ways to manage or control any stress you cannot avoid.
  • Be aware that some over-the-counter medicines and herbal remedies (like St John’s Wort) have things in them that can make your atrial fibrillation worse. Always get the advice of your doctor or pharmacist before taking them.
  • Go for regular check-ups. They will help you maintain your quality of life.

 

Diagnosis

Atrial Fibrillation

Atrial fibrillation can be detected by regular pulse checks and will only be diagnosed following a check-up with your doctor.

It is important to talk to your doctor if you have symptoms of atrial fibrillation.

In addition to a careful history and clinical exam, patients will usually have an ECG and ultrasound examination of the heart. Sometimes a coronary angiogram will be considered if there are symptoms suggesting angina or associated breathlessness.

The first step when someone develops atrial fibrillation or AFib is to look for any underlying cause or precipitating factors. The history may reveal a background of high blood pressure, heart valve disease or coronary artery disease.

Alcohol plays an important role in precipitating atrial fibrillation in many patients. An overactive thyroid gland is another potential cause which must be considered.

Often, a chest infection causing irritation around the heart may precipitate atrial fibrillation or certain operations, especially those involving the chest cage.

Other tests, including a blood pressure check and blood tests to measure how well your kidneys and thyroid gland are working, are usually carried out as well.

For more on regular pulse checks see here.

Treatment

Atrial Fibrillation

Treatment for your atrial fibrillation will depend on what is most appropriate for you.

Treatment is depending on the type and how long you have had it; how troublesome your symptoms are; and whether there is an underlying cause.

The mainstays of treatment are heart rate and rhythm control medication and some form of medication to minimise blood clot formation.

There are a number of different medications available some of which prevent the pulse rate from going too fast and others which have a direct action on the rhythm itself.

Other medications reduce the risk of blood clot formation and are known as blood thinners or anticoagulants. As with all medications there are potential side-effects and so the risks and benefits must be weighed up carefully before deciding what tablets are started.

There are also several other treatments that may be required to restore your normal regular rhythm including:

 

Cardioversion

Cardioversion is a procedure where an electrical shock is delivered through special paddles applied to the chest wall. Sometimes, even though the regular rhythm is restored, the atrial fibrillation may come back, so continued follow-up with or without medication is usually required.

 

Catheter Ablation

Ablation is a procedure that tries to find and remove the main cause of your atrial fibrillation. Narrow, flexible wires, are inserted into a blood vessel, often at the top of your leg or your neck and threaded up to your heart.

High frequency energy is sent through the wire to heat up and destroy an area of tissue that is causing the arrhythmia or irregular heart beat. The most common form of ablation is pulmonary vein isolation.

Resources

Atrial Fibrillation

Read our resources for further information:

  • View our AF and You booklet. A comprehensive look at everything to do with AFib, from what it is, to managing and living well with it.
Symptoms