Patient education
Atrial fibrillation Also called AFib or AF
Non-urgent referrals
Seen within 2 to 4 weeks
Urgent referrals
Seen within 1 to 2 weeks
Patients
Adults 18 and over
What atrial fibrillation is
Atrial fibrillation, usually shortened to AFib or AF, is the most common heart rhythm disorder.
Your heart has four chambers. Normally the two upper chambers, the atria, contract in a steady coordinated rhythm that pushes blood into the two lower chambers. In atrial fibrillation, the electrical signals in the atria become chaotic. Instead of contracting properly, the atria quiver. The lower chambers then beat irregularly, and often too fast.
Some people feel this immediately and unmistakably. Others have no idea it’s happening, and it’s found during a routine check or an ECG done for another reason. Both are common.
Symptoms
- A fluttering, pounding, thumping, or racing sensation in your chest
- Shortness of breath, particularly with exertion
- Tiredness or a general drop in energy and stamina
- Dizziness or lightheadedness
- Chest discomfort
- Reduced ability to exercise or do things you used to manage easily
Atrial fibrillation can be occasional, coming and going on its own over hours or days, or it can be constant. Episodes may be triggered by alcohol, illness, dehydration, poor sleep, or stress, or by nothing you can identify.
A significant proportion of people have no symptoms whatsoever. That doesn’t mean it can be ignored, because the stroke risk is present either way.
Why it matters
Two reasons.
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Stroke
When the atria quiver rather than contract, blood can pool and form a clot. If that clot travels to the brain, it causes a stroke. Atrial fibrillation raises stroke risk roughly fivefold, and strokes caused by AFib tend to be more severe than strokes from other causes. This risk is very effectively reduced with the right treatment, which is the main reason diagnosis matters.
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Heart function
A heart running fast and irregularly for long periods can weaken over time, leading to heart failure. This is usually reversible if the rhythm or rate is brought under control.
Who gets it
Risk increases with age, and it becomes considerably more common past 65. Other contributors include high blood pressure, obesity, sleep apnea, diabetes, alcohol use, thyroid problems, heart valve disease, previous heart attack, and a family history of the condition.
Endurance athletes have a somewhat higher rate than the general population, which surprises people.
Several of these are modifiable, and addressing them genuinely reduces how often AFib recurs.
How it’s diagnosed
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ECG
An electrocardiogram records your heart’s electrical activity and will show atrial fibrillation immediately, if you happen to be in it at the time.
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Holter or extended monitoring
Because AFib often comes and goes, a single ECG can easily miss it. A Holter monitor worn for 24 to 48 hours, or a longer-term event monitor worn for two weeks or more, records your rhythm during ordinary life and catches intermittent episodes. Holter monitoring is launching soon at this clinic.
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Echocardiogram
An ultrasound of the heart shows the size of the atria, how well the heart is pumping, and whether any valve problems are contributing. This directly informs treatment decisions.
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Blood work
Thyroid function, kidney function, electrolytes, and a blood count, since abnormalities in any of these can trigger or worsen AFib and change which medications are safe.
If you have a smartwatch that has flagged an irregular rhythm, bring those recordings to your appointment. They aren’t diagnostic on their own but they’re useful.
How it’s treated
Treatment has three separate parts, and most people need attention to all three.
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Reducing stroke risk
Your cardiologist calculates your individual stroke risk using a scoring system that accounts for age, blood pressure, diabetes, previous stroke, heart failure, vascular disease, and sex. Depending on that score, blood-thinning medication may be recommended. The medications used now are largely direct oral anticoagulants, which don’t require the frequent blood testing that warfarin did. This decision is individual: it weighs stroke risk against bleeding risk, and it’s a conversation, not a formula.
Aspirin is not adequate protection against stroke in atrial fibrillation. This is a common misunderstanding.
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Controlling the rhythm or the rate
Two broad approaches. Rate control accepts the irregular rhythm but slows it to a comfortable range, usually with beta blockers or calcium channel blockers. Rhythm control aims to restore and maintain normal rhythm, using antiarrhythmic medication, electrical cardioversion, or catheter ablation. Which approach suits you depends on your age, symptoms, how long you’ve been in AFib, and what your heart looks like on the echo.
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Addressing the drivers
Treating high blood pressure, losing weight if relevant, diagnosing and treating sleep apnea, reducing alcohol, and managing diabetes all measurably reduce how often AFib returns. This part is often underemphasized and it has a substantial effect.
What to expect at your appointment
Your first visit is a consultation with a cardiologist, lasting roughly an hour.
Bring with you
- A complete list of your medications and doses
- Any previous ECGs or monitor reports
- Any smartwatch or home blood pressure recordings you have
- A note of when episodes happen, how long they last, and what you were doing
Testing may be arranged the same day or shortly afterward. A letter goes back to your referring doctor, usually within 1 to 7 days.
Getting a referral
Ask your family doctor for a referral
You need a referral from a family physician or nurse practitioner.
Horizons Cardiopulmonary Diagnostics sees adult patients aged 18 and over.
Referring providers: referral forms and our current wait times are available on our referrals page.