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AF definitions, abbreviations and frequently used terms

Understanding cardiac arrhythmias - Click here to view a short video.


Arrhythmia Alliance
AAD Antiarrhythmic drug
Ablation A procedure to destroy or isolate the abnormal sources of electrical impulses that may be causing an arrhythmia. There are various kinds of ablation varying in invasiveness.
AC Anticoagulant
AED Automated External Defibrillator
AF Atrial fibrillation. May be paroxysmal (episodes which come and go), persistent, or permanent. Sometimes it is symptomatic, sometimes asymptomatic. Known as A-Fib in America.
Angina A heart condition that occurs when the blood supply to the muscles of the heart is restricted.
Antiarrhythmics A group of medications used to suppres the irregular rhythms of the heart.
Anticoagulants A group of medications used to slow down the speed at which the blood clots, to prevent blood clots. Anticoagulants are also known as 'blood thinners' although their mechanism does not actually thin the blood.
Arrhythmia Irregular heart rhythm
Arteries Blood vessels that carry blood away from the heart.
Asystole Cessation of heartbeat
Atrial flutter Rapid but regular atrial rhythm disorder
Atrium (plural atria) Top chambers of the heart that receive blood from the body and the lungs. The right atrium is where the heart's natural pacemaker (the sino-atrial node) is found.
Beta blockers Medicine used to slow the heart rate that can be prescribed in AF patients.
Blood clot A thickened mass in the blood formed by tiny substances called platelets.
Blood pressure The pressure exerted by the blood against the walls of blood vessels.
Bradycardia Slow heart rhythm
CAD Coronary artery disease
Cardiac arrest When the heart stops beating
Cardiac physiologist A staff member skilled in interpreting and providing information on your heart rhythm
Cardiac Resynchronisation Therapy (CRT) A pacemaker implanted under the skin to help with the symptoms of heart failure and to help improve heart function.
Cardiology department A hospital department where investigations for your heart take place
Cardiologist a doctor specialised in treating heart conditions
Cardioversion The use of a small energy shock to restore normal heart rhythm
Catheter ablation Form of ablation using thin flexible tubes to access the heart
CHA2DS2-VASc Scoring system used to calculate individual risk of AF-related stroke and the possible need for anticoagulation
CHD Coronary heart disease
Concomitant Secondary symptoms that occur, or procedures that are carried out, along with a main one
CVA Cardiovascular accident (stroke)
Defibrillation The use of high energy shock to stop fast heart rhythms
Dyspnoea Shortness of breath
Ectopic heartbeats Heartbeats which occur out of turn, where the heart may be felt to 'thump'. They are common and nearly always harmless.
Event monitor Monitor to record heartbeats
ECG / EKG Electrocardiography, when wires are placed on the chest to monitor the heart
Echocardiogram ... or just "echo". A three-dimensional soundwave image of the heart.
EEG Electroencephalography, when wires are placed on the head to read the electrical output of the brain
Electrophysiologist/EP Electrophisiologist, a specialist in cardiac electrophysiology
Hand held activator A small box allowing you to save information on your loop recorder
HAS-BLED Score system to determine bleeding risk
Heart attack Occurs when one of the coronary arteries becomes blocked by a blood clot. The blood supply to part of the heart muscle is blocked, causing part of the heart muscle to die. Also known as myocardial infarction.
Heart block When electrical impulses are slowed or blocked as they travel from the top to the bottom chambers of the heart
Heart failure A condition whereby the heart is not pumping sufficient blood for the body's needs
Hypertension High blood pressure
Hypotension Low blood pressure
Insertable loop recorder - A monitor implanted for a period of time to record your rhythm
ICD Implantable Cardioverter Defibrillator
LAA Left atrial appendage. A small pouch on the heart where clots can form. A procedure can close off (occlude) the pouch and thereby prevent clots from travelling to the brain and causing an AF-stroke.
OACs Oral anticoagulants (sometimes known as blood thinners) which may be divided into vitamin K antagonists (e.g. warfarin) or non-vitamin K antagonists (e.g. dabigatran).
NOACs New or novel oral anticoagulants introduced in the UK since 2012
Pacemaker A small, sealed electrical device which is connected to you heart. A pacemaker can monitor your heart and produce electrical impulses to treat abnormal heart rhythms
PAF Paroxysmal atrial fibrilaltion
PVI Pulmonary vein isolation
Pulse generator Part of the ICD which contains a battery and electric circuits
Sinus rhythm Normal rhythm of the heart
Stroke Also known as a 'brain attack'. Has differing levels of severity and recovery. Can be caused by a clot blocking an artery (ischaemic stroke) or a bleed (haemorrhagic stroke).
SVT Supraventricular Tachycardia - A rapid abnormal heart rhythm that begins in the upper chambers of the heart.
Syncope Loss of consciousness due to Bradycardia or asystole
TE Thromboembolism, where a blood clot becomes dislodged and blocks a blood vessel
TIA Transient Ischaemic Attack. A mild stroke from which recovery may be partial or total.
VATS Video-assisted thoracoscopic surgery - a form of keyhole surgery
Ventricles The two lower chambers of the heart. The right ventricle pumps blood into the lungs and the left ventricle pumps blood around the body.
Ventricular fibrillation A fast, dangerous heart rhythm which causes the heart to stop pumping. A shock can stop it and return the heart back to a normal rhythm. A cardiac arrest can soon follow if the rhythm is not treated quickly with a shock.
VKAs Vitamin K antagonists. A form of anticoagulants.
VT or V-Tach
Ventricular tachycardia - A fast rhythm which causes the heart to pump less efficiently, and can lead to dizziness, fainting and unconsciousness.