Atrial fibrillation is the most common heart rhythm disorder. Instead of contracting evenly, the upper chambers of the heart (the atria) beat in an uncontrolled and usually too-rapid way. As a result, blood is no longer pumped through the heart as efficiently as in a normal rhythm.¹
Atrial fibrillation is very common and is one of the most frequent reasons for cardiology consultations. The risk rises sharply with age.¹˒⁴
2. Symptoms
Symptoms vary widely — some people feel their atrial fibrillation clearly, while others barely notice it or don't notice it at all:¹
Tricky: silent atrial fibrillation
Many people don't feel their atrial fibrillation at all. It is then often discovered only during a medical examination or — in the worst case — after a stroke.
3. Why is atrial fibrillation dangerous?
The main risk is stroke. The irregular blood flow can cause blood clots to form in the atria. If a clot breaks loose, it can travel to the brain and block a blood vessel there. Without appropriate blood thinning, the risk of stroke in atrial fibrillation is significantly increased.¹˒⁴
In addition, over the long term atrial fibrillation can weaken the heart's pumping power and worsen existing heart conditions (such as heart failure).
Signs of a stroke — call 112 immediately!
Sudden one-sided paralysis or weakness · Difficulty speaking or understanding speech · Vision problems or double vision · Sudden severe headache · Dizziness or unsteady gait. If you notice these signs, call the emergency number 112 immediately — every minute counts.
4. Causes and risk factors
High blood pressure (hypertension) — considered the most common cause
ECG: The gold standard — it shows the irregular rhythm directly. However, intermittent (paroxysmal) atrial fibrillation is often not captured on a resting ECG.
Long-term ECG (Holter monitor): A recording over one to several days. It also captures intermittent atrial fibrillation that wasn't visible on a resting ECG.
Smartwatch/wearable: Can provide indications of atrial fibrillation — but it is no substitute for a medical ECG diagnosis. If you get an alert, you should generally see a cardiologist.
Echocardiography: An ultrasound of the heart — it assesses the size of the atria, the pumping function and any valve defects.
For most patients with atrial fibrillation, long-term blood thinning is necessary. The individual risk is calculated using the CHA₂DS₂-VASc score.⁴
DOACs (direct oral anticoagulants) — the standard today
Apixaban, rivaroxaban, edoxaban and dabigatran. Easier to manage than vitamin K antagonists — regular clotting tests are usually not required. Learn more: Blood thinners in everyday life.
Vitamin K antagonists — phenprocoumon (Marcumar/Falithrom), warfarin
An older class of medication. The INR value must be checked regularly. Many interactions with foods and other medications.
Never stop taking blood thinners on your own!
Otherwise the risk of stroke rises significantly. Even before dental appointments or minor procedures: always check with your doctor first.
These lower the heart rate and are considered the first choice for most patients.
Calcium channel blockers — verapamil, diltiazem
An alternative if beta blockers are not tolerated.
Digitalis — digoxin
Used as an add-on, often when heart failure is also present.
Goal 3Rhythm control — restoring a normal heart rhythm
Flecainide
In certain cases it can also be used as an as-needed medication for intermittent atrial fibrillation — the decision is always made by your cardiologist.
Amiodarone
Considered one of the most effective rhythm medications, but it has a notable side-effect profile (affecting the thyroid, lungs and liver, among others). It is generally used only for atrial fibrillation that is difficult to treat.
A controlled electrical impulse, delivered under brief general anesthesia, resets the heart to a normal sinus rhythm. This is usually an outpatient procedure.
Catheter ablation (pulmonary vein isolation)
A minimally invasive procedure in which a catheter is guided to the heart via the groin. Faulty electrical signals are deliberately scarred over (pulmonary vein isolation). It is particularly effective for intermittent atrial fibrillation and in younger patients. In a substantial proportion of those treated, atrial fibrillation can be eliminated or markedly reduced over the long term.⁴
8. Living with atrial fibrillation
Check your pulse: Regularly — at the wrist or with a smartwatch. If your pulse is irregular, inform your cardiologist.
Blood thinners: Take them on time and regularly. In case of injuries or bleeding, inform your doctor. Always carry your medication ID card.
Alcohol: Can trigger or worsen atrial fibrillation. In most cases it's advisable to largely avoid it, or at least to cut consumption significantly. Learn more: Medication and alcohol.
Exercise: Moderate activity is generally recommended (e.g. swimming, cycling, walking). For extreme or high-performance sport: discuss it individually with your cardiologist.
Comorbidities: Consistently treat blood pressure, diabetes and excess weight — this can usually reduce the frequency and severity of atrial fibrillation episodes.
How brite helps you with atrial fibrillation
Blood thinners on time, never forgetting your heart medications, checking for interactions — with atrial fibrillation, reliability matters more than ever.
Medication reminders — Blood thinners, beta blockers, rhythm medications: taking heart medications on time is especially important. Set up a reminder
Interaction check — Blood thinners + painkillers? + antibiotics? Check for interactions for free. Check now
Health tracking — Record your pulse, heart rhythm episodes and symptoms. Track your history
Digital medication plan — all your heart medications clearly laid out for your cardiologist and emergency doctor. Go to medication plan
Without treatment, atrial fibrillation can significantly increase the risk of stroke. With appropriate blood thinning and treatment, however, the condition can usually be well controlled, and most people can lead a largely normal life.¹˒⁴
For most patients with atrial fibrillation, long-term blood thinning is usually recommended. The individual risk is calculated using the CHA₂DS₂-VASc score. The decision is always made by your treating cardiologist.⁴
A minimally invasive procedure in which faulty electrical signals in the heart are deliberately scarred over (pulmonary vein isolation). In a substantial proportion of those treated, this can eliminate atrial fibrillation over the long term or markedly reduce it. The chances of success depend on factors such as the type of atrial fibrillation and individual circumstances.⁴
Yes — moderate activity is generally even recommended (e.g. swimming, cycling, walking). For extreme or high-performance sport, you should consult your cardiologist.
Modern smartwatches can provide indications of atrial fibrillation. However, they are no substitute for a medical ECG diagnosis. If you get an alert, you should generally see a cardiologist.
German Heart Foundation (Deutsche Herzstiftung): Atrial Fibrillation — Information and Guidance. herzstiftung.de
German Heart Center of the Charité (DHZC): Atrial Fibrillation. dhzc.charite.de
German Heart Foundation: Medications for Atrial Fibrillation. herzstiftung.de
ESC Guidelines: Management of Atrial Fibrillation (2024). escardio.org
Medical disclaimer: This article is for general information only and is not a substitute for medical advice, diagnosis or treatment. Blood thinners should never be stopped on your own — doing so can significantly increase the risk of stroke. If you notice signs of a stroke (sudden one-sided paralysis, difficulty speaking, vision problems), call the emergency number 112 immediately. The choice of medication and dosage is always determined individually by your treating cardiologist. Last updated: April 2026.
