Atrial Fibrillation

What is Atrial Fibrillation?

Atrial fibrillation (AF) is an irregular heart rhythm that begins in the upper chambers of the heart (the atria). Instead of beating normally, the atria quiver chaotically, resulting in a fast or irregular pulse.

AF affects hundreds of thousands of Canadians and is the most common sustained heart rhythm abnormality. While it isn’t immediately life-threatening, it can increase the risk of stroke, heart failure, and reduced quality of life if not treated.

What Does AF Feel Like?

Some people feel nothing at all — but others may notice:

A racing or irregular heartbeat
Fatigue or low energy
Shortness of breath
Dizziness or lightheadedness
Chest discomfort or palpitations
Poor exercise tolerance

Why Does Atrial Fibrillation Matter?

AF can lead to serious complications:

Increased risk of stroke
Higher chance of severe or disabling stroke
Risk of developing heart failure
Long-term association with memory problems or cognitive decline

What Causes AF?

AF becomes more common with age and may be triggered by:

High blood pressure
Heart valve disease
Coronary artery disease or prior heart attack
Sleep apnea
Excess alcohol or stimulant use
Thyroid problems
Genetic predisposition
Sometimes, no clear cause is found

How is AF Diagnosed?

AF is diagnosed using heart rhythm recordings, including:

Electrocardiogram (ECG): In-office test
Holter monitor or patch monitor: Worn for 24 hours to 2 weeks
Loop recorder: Implanted under the skin for long-term monitoring
Echocardiogram: Ultrasound of the heart to check structure/function
Blood tests: To assess thyroid, kidney function, and electrolytes

Treatment: A Multifaceted Approach

AF treatment is highly individualized and usually includes a combination of:

Stroke Prevention (Anticoagulation)

If you’re at increased stroke risk (based on your age and medical history), your doctor may recommend a blood thinner such as:

Apixaban, rivaroxaban, or similar medications

These drugs dramatically reduce stroke risk, but must be taken consistently and monitored for bleeding risk.

Heart Rate Control

Medications like beta-blockers, calcium channel blockers, or digoxin help control how fast the heart beats
Often the first approach in older adults or those with mild symptoms

Rhythm Control (for some people)

Antiarrhythmic medications may help restore or maintain a normal rhythm
Cardioversion may be used to “reset” the rhythm electrically
Catheter ablation is a minimally invasive procedure that targets the source of AF, especially useful when medications are not tolerated or effective

💊 Common Medications for Atrial Fibrillation

Medication Class	Examples	What It Does	Common / Important Side Effects
Direct Oral Anticoagulants (DOACs)	Apixaban (Eliquis), Rivaroxaban (Xarelto), Dabigatran (Pradaxa), Edoxaban (Lixiana)	Reduce stroke risk by preventing blood clots	Bleeding, bruising, adjustment needed if kidney/liver function abnormal
Warfarin (Vitamin K antagonist)	Warfarin (Coumadin)	Older blood thinner; still used in some situations	Bleeding, needs regular INR monitoring, dietary restrictions
Beta Blockers	Metoprolol, Bisoprolol, Atenolol	Slow the heart rate; help with AF symptoms	Fatigue, low heart rate, dizziness, low mood, low libido
Calcium Channel Blockers (non-dihydropyridine)	Diltiazem, Verapamil	Slow the heart rate; control symptoms	Constipation, low BP, swelling, dizziness
Digoxin	Digoxin	Helps control heart rate, especially at rest	Nausea, visual changes, dizziness, risk of toxicity (narrow therapeutic range)
Antiarrhythmic Medications	Flecainide, Propafenone, Sotalol, Amiodarone	Help maintain normal heart rhythm	See below for drug-specific details
	Flecainide, Propafenone	Used in patients with structurally normal hearts	Can cause dangerous rhythms if heart is not healthy
	Amiodarone	Very effective for rhythm control; used when others fail	Lung, liver, thyroid, and eye side effects; skin discoloration; photosensitivity
	Sotalol	Beta-blocker with rhythm-stabilizing properties	Low heart rate, dizziness, may cause QT prolongation and arrhythmia

What About Atrial Flutter?

Atrial flutter is another type of abnormal heart rhythm that, like atrial fibrillation, starts in the upper chambers of the heart (the atria). Instead of the chaotic, quivering activity seen in AF, atrial flutter involves a very fast but organized rhythm, often at around 300 beats per minute in the atria.

It shares many of the same:

Symptoms (palpitations, shortness of breath, fatigue)
Risks (especially stroke)
Treatment approaches (anticoagulation, rate control, rhythm control)

Atrial flutter can occur on its own or alternate with atrial fibrillation in the same person. In fact, many patients with atrial flutter will eventually develop atrial fibrillation as well.

One key difference: catheter ablation is often more successful and definitive in treating typical atrial flutter than it is for atrial fibrillation. A simple ablation targeting the flutter circuit (usually in the right atrium) can permanently restore normal rhythm in many cases⁸.Living with Atrial Fibrillation

AF can come and go or be persistent
Avoid common triggers like alcohol, dehydration, poor sleep, and stress
Follow your medication plan closely
Stay up to date with your doctor visits
Many people with AF live long, full lives with the right treatment

Living with Atrial Fibrillation

AF can be episodic (paroxysmal) or ongoing (persistent/permanent). Many people live well with AF when it is appropriately managed. Tips include:

Avoid triggers such as alcohol, caffeine, dehydration, and poor sleep
Take medications exactly as prescribed
Attend regular follow-up appointments
Monitor your heart rate and symptoms

Learn More

Heart & Stroke Foundation