Causes
AFib can be caused by damage to the heart's structure, often due to underlying conditions. It becomes more common with age. Factors that can lead to AFib include:- High Blood Pressure (Hypertension): The most common risk factor, as it can stiffen and thicken the heart muscle, affecting its electrical activity.
- Coronary Artery Disease (CAD): Narrowed arteries reduce blood flow to the heart, potentially damaging heart tissue.
- Heart Attack: Damage to the heart muscle from a heart attack can disrupt electrical signals.
- Heart Failure: A weakened heart muscle struggles to pump blood effectively, leading to chamber enlargement and electrical issues.
- Heart Valve Disease: Damaged or leaky heart valves can cause the atria to enlarge or work harder.
- Overactive Thyroid (Hyperthyroidism): Excess thyroid hormone can speed up the heart rate and contribute to arrhythmias.
- Congenital Heart Defects: Heart abnormalities present at birth.
- Lung Diseases: Chronic lung conditions like COPD or asthma can strain the heart.
- Sleep Apnea: Repeated pauses in breathing during sleep can affect heart rhythm.
- Obesity: Increases the risk of AFib and other heart conditions.
- Excessive Alcohol Consumption: Particularly binge drinking, often referred to as "holiday heart syndrome."
- Stimulants: Caffeine, nicotine, and certain medications (e.g., cold and cough medicines containing pseudoephedrine).
- Stress: High levels of stress can sometimes trigger AFib episodes.
- Family History: A genetic predisposition can increase risk.
- Age: Risk increases significantly with age.
Symptoms
Some people with AFib have no symptoms and are only diagnosed during a routine physical exam. When symptoms do occur, they can include:- Palpitations: A sensation of a rapid, fluttering, or pounding heartbeat.
- Shortness of breath: Especially during exertion or at rest.
- Fatigue and weakness.
- Dizziness or lightheadedness.
- Fainting (syncope).
- Chest pain or pressure: Can be a sign of a more serious heart problem.
- Confusion.
Diagnosis
Diagnosing AFib involves a physical examination and tests to assess heart rhythm and structure.- Medical History and Physical Exam: The doctor will ask about your symptoms, medical history, lifestyle, and family history. They will check your pulse for irregularity.
- Electrocardiogram (ECG/EKG): This is the primary diagnostic tool. It records the electrical activity of your heart and can show if your heart is beating irregularly.
- Holter Monitor: A portable ECG device worn for 24-48 hours (or longer) to record heart activity during daily routines, catching intermittent AFib episodes.
- Event Recorder: A portable device worn for weeks or months that you activate when you feel symptoms, or it may automatically record abnormal rhythms.
- Implantable Loop Recorder: A small device implanted under the skin to continuously monitor heart rhythm for up to several years.
- Echocardiogram: An ultrasound of the heart to visualize its structure and function, check for valve problems, or assess for heart failure.
- Blood Tests: To check for underlying conditions like thyroid problems, kidney function, and electrolyte imbalances.
- Chest X-ray: To check the condition of the lungs and heart.
- Stress Test: May be performed to evaluate heart function during exertion.
Treatment
Treatment for AFib aims to:- Control heart rate: Slow down a rapid heart rate.
- Control heart rhythm: Restore and maintain a normal heart rhythm.
- Prevent blood clots: Reduce the risk of stroke.
- Manage underlying conditions.
- Medications:
- Rate Control Medications: Slow the heart rate (e.g., beta-blockers, calcium channel blockers, digoxin).
- Rhythm Control Medications (Antiarrhythmics): Help restore and maintain a normal heart rhythm (e.g., flecainide, propafenone, amiodarone, sotalol).
- Anticoagulants (Blood Thinners): Reduce the risk of stroke by preventing blood clots (e.g., warfarin, dabigatran, rivaroxaban, apixaban, edoxaban). This is a critical part of AFib management for most patients.
- Procedures:
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- Cardioversion: Delivers an electrical shock to the heart to reset its rhythm. Can be done electrically or with medications.
- Catheter Ablation: A procedure where thin, flexible tubes (catheters) are inserted into the heart to create small scars that block abnormal electrical signals causing AFib.
- Left Atrial Appendage Occlusion: For some patients who cannot take blood thinners, a device is implanted to close off the left atrial appendage, where most stroke-causing clots form in AFib.
- Pacemaker Implantation: May be used if AFib causes a very slow heart rate.
- Maze Procedure: A surgical procedure to create scar tissue in the atria to block abnormal electrical signals.
- Lifestyle Changes:
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- Manage underlying conditions: Control blood pressure, diabetes, and thyroid issues.
- Healthy Diet: Heart-healthy eating.
- Regular Exercise: As advised by your doctor.
- Maintain a Healthy Weight.
- Limit Alcohol and Caffeine.
- Quit Smoking.
- Manage Stress.
Living With Atrial Fibrillation
Atrial fibrillation is rarely dangerous in the moment and frequently dangerous over years, because the harm comes from the strokes it causes rather than the palpitations it produces. That shapes every treatment decision, and the most important one is made at diagnosis.
Stroke prevention is the decision that matters most
Whether you need a blood thinner depends on a risk score built from age, sex, blood pressure, diabetes, heart failure, vascular disease, and any prior stroke, not on how often you feel the rhythm. Most people over 65 with atrial fibrillation qualify. A direct oral anticoagulant such as apixaban or rivaroxaban is preferred over warfarin for most patients, and aspirin is not a substitute: it barely reduces stroke risk in atrial fibrillation while carrying most of the bleeding risk.
Bleeding fears in proportion
The fear of bleeding leads many people who should be anticoagulated to go without. Falls are not a reason to withhold treatment; a person would need to fall many times a year for the bleeding risk to outweigh the stroke risk. The modifiable contributors to bleeding are uncontrolled blood pressure, NSAIDs such as ibuprofen, heavy alcohol use, and unnecessary aspirin, and those are what a bleeding-risk score is designed to fix, not a reason to stop the anticoagulant.
Rate control, rhythm control, and when ablation is worth it
Metoprolol or diltiazem slows the heart and relieves most symptoms. Restoring normal rhythm with medication or catheter ablation is increasingly favored early, particularly within the first year of diagnosis and in people with heart failure, because it reduces hospitalization and cardiovascular events rather than only improving symptoms. Ablation is now a reasonable first choice for symptomatic intermittent atrial fibrillation rather than a last resort.
The risk factors that change the course
Losing 10 percent of body weight substantially reduces the burden of atrial fibrillation and improves the success of ablation. Treating obstructive sleep apnea, which is present in a large share of people with the condition, controlling blood pressure, and cutting alcohol to a minimum each lower recurrence. These are treatments, not lifestyle suggestions, and they work alongside medication.
Knowing when it is happening
Many episodes cause no symptoms, which is why anticoagulation continues even when you feel fine. A smartwatch ECG or a regular pulse check can catch episodes, and our heart palpitations article explains which sensations warrant a recording. Chest pain, fainting, severe breathlessness, or any stroke symptom during an episode is an emergency. Our cardiovascular team manages anticoagulation and rate control alongside cardiology. The American Heart Association and NHLBI publish detailed patient guidance.
If you have atrial fibrillation and are not sure whether you should be on a blood thinner, or stopped one because of bleeding worries, schedule a review.