Atrial fibrillation
Also called: AF, AFib, irregular heartbeat, atrial flutter (a closely related rhythm), paroxysmal atrial fibrillation
Atrial fibrillation (AF) is a common heart rhythm problem that makes the heartbeat irregular and often fast. It can cause palpitations, tiredness and breathlessness, and it raises the risk of stroke. Blood thinners lower that risk, and other medicines or procedures control the heartbeat.
General health information for Pakistan. It does not give doses or brand advice. If you are worried, or symptoms are severe, see a doctor. When to see a doctor
Overview
Atrial fibrillation (AF) happens when the electrical signals in the upper chambers of the heart (the atria) become chaotic. Instead of squeezing in a steady pattern, the atria quiver. The heartbeat becomes irregular and is often faster than 100 beats a minute. Some people feel palpitations (a racing, pounding or fluttering heartbeat), while others feel nothing and only find out at a routine check.
AF can come and go on its own (paroxysmal), last until treatment stops it (persistent), or stay long term (permanent). It becomes more common with age and is often linked to high blood pressure, heart disease, heart valve problems, an overactive thyroid or heavy drinking. Atrial flutter is a related rhythm problem that is fast but more regular, and it is treated in a similar way.
The biggest danger is stroke. Because blood does not flow smoothly through the quivering atria, clots can form there and travel to the brain. This is why many people with AF need an anticoagulant (blood thinner). Treatment also aims to control the heart rate or bring back a normal rhythm, and to manage the health problems that drive AF. There is no simple cure, but most people live normal, active lives with the right care.
In Pakistan
In a study at the Armed Forces Institute of Cardiology in Rawalpindi, only about 4 in 10 people with AF taking warfarin kept their INR in the safe range most of the time, and taking many medicines or having several illnesses made control worse. About a third of these patients had AF linked to heart valve disease, where warfarin rather than a DOAC is usually needed.
Symptoms
- Palpitations: a heartbeat that feels like it is racing, pounding, fluttering or skipping beats
- An irregular or uneven pulse
- A fast heart rate, often over 100 beats a minute when resting
- Feeling tired or weak, or being less able to exercise
- Breathlessness
- Dizziness, light-headedness or feeling faint
- Chest pain or tightness
- No symptoms at all in some people, so AF may be found only during a check-up or a test for something else
Causes and risk factors
Causes
- High blood pressure, which strains the heart over many years
- Heart conditions such as coronary heart disease, a past heart attack, heart failure or heart surgery
- Heart valve disease, most often of the mitral valve
- An overactive thyroid gland (hyperthyroidism)
- Alcohol, especially binge drinking
- Some medicines, and other illnesses such as pericarditis (inflammation of the sac around the heart) or sick sinus syndrome (a fault in the heart's natural pacemaker)
What makes it more likely
- Being aged 55 or over, with risk rising further with age
- Being male
- Being overweight or obese
- Smoking
- Drinking too much alcohol
- Diabetes, chronic kidney disease or sleep apnoea (breathing pauses during sleep)
- Very intense endurance sport over many years, such as long-distance running or cycling
Complications
The most serious complication of AF is stroke. Blood can pool in the quivering upper chambers and form clots, which may travel to the brain and block a blood vessel. AF can also lead to heart failure, especially when the heart beats too fast for a long time. The condition often comes back and can get worse over time, even with treatment. Blood thinners lower the risk of stroke, but they raise the chance of bleeding, so doctors weigh the benefits and risks for each person and review this at least once a year.
When to see a doctor
- A fast or irregular heartbeat together with chest pain, severe breathlessness, sweating, or feeling sick or vomiting: call an ambulance now
- A fast or irregular heartbeat with fainting, severe dizziness or a fall: call an ambulance now
- Signs of a stroke, such as a drooping face, weakness or numbness on one side of the body, loss of vision, confusion or difficulty speaking: call an ambulance now
- A fast or irregular heartbeat with a sudden, severe headache: get emergency help now
- Heavy or unusual bleeding while taking a blood thinner: get urgent medical help
- Palpitations that keep coming back or are getting worse, or AF symptoms that are not controlled by treatment: see your doctor soon
Diagnosis
A doctor first feels your pulse to check whether it is irregular. If AF is suspected, a 12-lead ECG (electrocardiogram, a tracing of the heart's electrical activity) is the key test to confirm it. Because AF can come and go, a normal ECG does not always rule it out. Your doctor may then ask you to wear a portable heart monitor for 24 hours or longer, or use an event recorder or patch monitor for days or weeks, so that an episode can be caught.
An echocardiogram (an ultrasound scan of the heart) is often done to look for valve problems or a weak heart muscle, and before some treatments. Blood tests, including thyroid tests, and sometimes a chest X-ray help find causes. Your doctor will also work out your stroke risk with a scoring tool called CHA2DS2-VASc and your bleeding risk with a tool such as ORBIT. These scores guide whether you need a blood thinner.
Treatment
- Find and treat the causes and conditions that drive AF, such as high blood pressure, an overactive thyroid, heart failure, diabetes, sleep apnoea, excess weight and heavy drinking.
- Assess stroke and bleeding risk. If your stroke risk is raised, your doctor will usually offer a direct oral anticoagulant (DOAC). Warfarin is used when a DOAC is not suitable, for example in people with a mechanical heart valve or mitral stenosis (a narrowed mitral valve). Aspirin on its own is not used to prevent stroke in AF.
- Control the heart rate, usually first with a beta blocker or a rate-limiting calcium channel blocker (verapamil or diltiazem). Digoxin may be used for people who are not very active, and two medicines may be combined if one is not enough. Your doctor decides which medicine and the dose.
- If symptoms continue despite rate control, a specialist may try rhythm control to bring back a normal heartbeat. This can mean electrical cardioversion (a controlled shock to reset the rhythm) or antiarrhythmic medicines such as amiodarone, flecainide or dronedarone, chosen according to the health of your heart.
- If medicines do not work or are not suitable, a specialist may offer catheter ablation (a procedure that scars the small areas of heart tissue that trigger AF). In some younger people with few other health problems, ablation may be offered earlier.
- For people who cannot take a blood thinner at all, a specialist may consider left atrial appendage occlusion (a small implant that closes off the part of the heart where most clots form). For some people with permanent AF and a very fast rate, a pacemaker with ablation of the heart's electrical junction is an option.
- Have regular reviews, at least once a year, to check your symptoms, your stroke and bleeding risk and how well your medicines are working. If treatment does not control your symptoms, ask to be referred to a heart specialist.
Medicines in Pakistan
Medicines a doctor may use, by group. Each link opens our page for that medicine, with every brand and its official DRAP price. Your doctor decides which medicine and dose are right for you.
| Group | Role | Medicines |
|---|---|---|
| Direct oral anticoagulants (DOACs) | first choice to prevent stroke when stroke risk is raised; the doctor chooses which one with you | Apixaban (31 brands), Rivaroxaban (214 brands), Dabigatran etexilate (5 brands) |
| Vitamin K antagonist anticoagulant | used when a DOAC is not suitable, such as with a mechanical heart valve or mitral stenosis; needs regular INR blood tests to keep the dose in the right range | Warfarin (24 brands) |
| Beta blockers | first choice to slow the heart rate, and also used first for long-term rhythm control; preferred if you also have heart failure | Bisoprolol fumarate (127 brands), Metoprolol Tartrate (7 brands), Atenolol (27 brands), Carvedilol (13 brands) |
| Rate-limiting calcium channel blockers | an alternative to a beta blocker to slow the heart rate; usually avoided in people who also have heart failure | Verapamil (14 brands) |
| Cardiac glycosides | slows the heart rate in people with long-lasting AF who are not very active, or added to another rate medicine | Digoxin (10 brands) |
| Antiarrhythmics | used by specialists to restore or keep a normal rhythm, for example around cardioversion or when the heart muscle is weak; not used long term just to slow the rate because of side effects | Amiodarone (11 brands) |
Also used (not yet in our price list): edoxaban (a DOAC), diltiazem (a rate-limiting calcium channel blocker), flecainide (an antiarrhythmic, avoided in people with heart disease such as past heart attack), propafenone (an antiarrhythmic), dronedarone (an antiarrhythmic)
Self-care and prevention
Self-care
- Take your blood thinner exactly as prescribed and do not stop it without talking to your doctor, because stopping raises the risk of stroke
- Tell every doctor, dentist and pharmacist that you take a blood thinner, and ask before using painkillers such as NSAIDs or other new medicines, as some raise the risk of bleeding
- If you take warfarin, go for your INR blood tests as advised and keep your diet and alcohol intake steady
- Learn your own triggers and avoid them; common ones include caffeine, alcohol, stress, dehydration and poor sleep
- Drink little or no alcohol, and avoid binge drinking
- Stop smoking
- Keep a healthy weight and stay active, aiming for at least 150 minutes of moderate activity a week, but avoid very intense exercise and rest if you have symptoms
- Keep your blood pressure, diabetes and any sleep apnoea well controlled
Prevention
- Keep blood pressure under control
- Keep a healthy weight and eat a balanced diet
- Stay physically active
- Do not smoke
- Limit alcohol and avoid binge drinking
- Get treatment for conditions linked to AF, such as an overactive thyroid, diabetes and sleep apnoea
Common questions
Is atrial fibrillation dangerous?
AF can lead to stroke and heart failure, so it should always be checked and treated. Blood thinners lower the stroke risk, and other treatments control the heartbeat. With the right care, most people can carry on with their normal activities.
Can atrial fibrillation be cured?
There is no simple cure, and AF often returns. Medicines and procedures such as cardioversion or ablation can control it well, and some people stay in a normal rhythm for a long time. Treating causes such as high blood pressure, excess weight and heavy drinking also helps.
Why do I need a blood thinner if I feel fine?
Clots can form in the heart even when AF causes no symptoms. Your doctor uses a stroke risk score to decide whether a blood thinner is right for you. Being older or at risk of falls is not by itself a reason to stop or avoid one.
Can I take aspirin instead of a blood thinner?
No. Guidelines say aspirin on its own does not protect people with AF from stroke well enough. An anticoagulant such as a DOAC or warfarin is used instead when stroke risk is raised.
Can I still exercise with atrial fibrillation?
Yes. Regular moderate exercise is good for people with AF and helps control risk factors. Avoid very intense exercise, and stop and rest if you get symptoms. Ask your doctor what is safe for you.
Sources
- NICE. Atrial fibrillation: diagnosis and management (NG196) (2021, updated June 2021).
- ESC. 2024 ESC Guidelines for the management of atrial fibrillation (2024).
- ACC. 2023 Guideline for Diagnosis and Management of Atrial Fibrillation: Key Perspectives (2023).
- NHS. Atrial fibrillation - NHS (2026 (accessed)).
- MedlinePlus (US National Library of Medicine). Atrial fibrillation and atrial flutter: MedlinePlus Medical Encyclopedia (2025).
- Pakistan Armed Forces Medical Journal. Anticoagulation Control Among Patients with Atrial Fibrillation (2020).
Prepared from the sources listed below by the MedInfoBase team. Last reviewed 16 October 2026. This page is general health information, not medical advice. It gives no doses and does not replace a doctor: talk to your doctor or pharmacist before starting, stopping or changing any medicine. How we write and check our pages.
Related conditions
High blood pressure (hypertension)Heart failureStrokeCoronary artery disease (angina)Overactive thyroid (hyperthyroidism)Type 2 diabetes mellitus