Atrial Fibrillation
Atrial Fibrillation
As your heart beats (heart rate), the chambers of your heart squeeze and relax, pumping blood around the body in a regular pattern (which is known as heart rhythm).
This heartbeat is created in an area called the sinus node, which is like the heart’s fuse box. It generates an electrical current that creates waveforms we can see on a ECG, and this pattern is called your heart rhythm.
The pulse rate can vary from person to person and can also change depending on what activities you are doing.
On average, a normal heart rate is between 60-100 beats per minute.
With atrial fibrillation, the heart beats irregularly and can be either too fast or too slow, almost like it’s quivering instead of beating properly. This can cause blood to pool in the heart, which may lead to blood clots.
All forms of atrial fibrillation (AF) represent a potentially significant risk for stroke.
People with A Fib have a 4 to 5 time’s higher risk of stroke. This heightened risk is due to the formation of blood clots in the atria, which can travel to the brain and cause an ischemic stroke.
To understand AF you need to know a little about how your heart works. Your heart is a muscle about the size of a clenched fist and is located slightly to the left of the centre of your chest. The heart has four chambers – two upper ones, called the right and left atria, and two lower ones called the right and left ventricles. The heart’s function is to pump blood all around the body. It does this via its own electrical system driven by its natural internal pacemaker and this causes the heart to beat regularly.
Heart rate and heart rhythm are the different ways the heart pumps.
The heart rate is the number of times your heart beats in a minute. For most people, normal heart rate is between 60 and 100 beats per minute (although it can vary from person to person and can depend on what you are doing). The heart rhythm is how regular or irregular the beats are. Normal heart rhythm is known as sinus rhythm. Both the heart rate and the heart rhythm need to be regular for your heart to work as best it can.
With atrial fibrillation, a problem with the heart’s electrical system causes the two upper chambers of the heart (the atria) to quiver or beat in a disorganised pattern. This upsets the rhythm between the upper and lower chambers and results in the ventricles beating faster without a regular rhythm.
There are different types of Atrial Fibrillation – diagnosis of AF is made on your symptoms and ECG /monitor results:
- New diagnosis of AF – had not been detected before and diagnosed with a 12 lead ECG
- Paroxysmal AF – an irregular pulse that comes and goes. Usually returns to regular pulse in less than 48 hours But can last up to 7 days
- Persistent AF – AF that is there longer than 7 days
- Permanent AF – AF than has not responded to treatment like cardioversion and needs to be managed with medication life long
The signs and symptoms of AF vary from person to person. Some people have no symptoms at all and only get a diagnosis when attending their GP or Health Check. Some may feel some of the below from time to time:
- Asymptomatic
- Palpitation or Fluttering sensation in chest
- Dizziness / Fatigue
- Tiredness
- Short of breath
- Chest pain or discomfort
If you feel you have any symptoms of AF, it is important to see your doctor as soon as possible.
The causes of AF are not always clear or easy to determine and sometimes there is no known cause. AF can affect people of any age, but it is more common in people over 65. The risk factors that increase the likelihood of developing AF are:
- High blood pressure
- Coronary heart disease
- Heart attacks
- Disease of the heart valves
- Heart failure
- Overactive thyroid gland
- Lung infections such as pneumonia
- Blood clots in the lungs (pulmonary embolism)
- Previous heart or lung surgery
- Diabetes
- Sleep apnoea (interrupted breathing while sleeping)
- Drug or alcohol abuse.
If you are having signs or symptoms of AF, you will need to visit your doctor. Regular pulse checks can help to detect AF. After a physical examination, there are a number of tests your doctor may recommend in order to diagnose whether or not you have AF. These tests may include:
- Electrocardiogram (ECG): The ECG test measures and records your heart rhythm and rate. It usually just takes a few minutes and can be done at your doctor’s surgery or in hospital. This is the main test used to diagnose AF.
- 24 Hour ECG Recording (Holter Monitor): In some cases, it may be necessary to monitor the heart over a 24-hour period. You wear a small recording device for 24 hours, usually around your waist, and it records the electrical activity of your heart.
- Echocardiogram (Echo): This test is an ultrasound of the heart and is used to detect if there are any problems with the heart muscle or valves that are contributing to the irregular heart rhythm.
- Cardiac Event Recorders: If you do not get symptoms, very often your doctor may use other devices to diagnose your irregular heart rhythm, including a cardiac event recorder or an implantable loop recorder. These record the electrical activity of your heart over a longer period of time.
- Coronary Angiogram: This is an additional test that may be carried out to determine if there is any narrowing of the coronary arteries that supply blood to the heart muscle.
The management of A Fib is complex and lifelong. Knowing your numbers and to check your own pulse will improve your overall management.
- Recognise signs and symptoms that you may have
- Medication to prevent a clot formation – anti coagulation
- Medication to both manage your heart rate and heart rhythm
- Cardioversion – a procedure to regulate the hearts rhythm for symptomatic patients with persistent or long standing AF
- Support with management of lifestyle modification
- Screening to prevention a Stroke
- Multidisciplinary team approach to care
- Structure follow up to support your needs
Living with AF
AF is not immediately life-threatening in the same way as some arrhythmias (irregular heartbeats) are. Most people are able to live full and active lives with AF. You can do this by taking your prescribed medication, following the medical advice you received from your doctor, having regular medical check-ups and making positive lifestyle changes.
If you have any questions or concerns, contact the Croí Health Team on 091-544310 or email healthteam@croi.ie.