Heart Racing or Fluttering
Quick answer
A racing or fluttering heartbeat (palpitations) is often harmless, triggered by caffeine, stress or extra beats. It can also signal an arrhythmia such as atrial fibrillation. A doctor should check palpitations that recur or come with symptoms. Seek urgent care if palpitations come with fainting or chest pain.
Medically reviewed by The Curaventa Team · Last updated 2026-10-24
Get urgent care if
- Fainting or near-fainting
- Chest pain
- Severe breathlessness
- Palpitations with very fast pulse that won't stop
Possible causes
| Condition | Why it can cause this |
|---|---|
| Atrial Fibrillation (AFib) | an irregular, often fast rhythm |
| Arrhythmia (Irregular Heartbeat) | other fast rhythms like SVT |
| Overactive thyroid | speeds up the heart |
| Anxiety or caffeine | common harmless triggers |
| Heart Valve Disease | can lead to rhythm changes |
Tests a doctor may order
- ECG
- Holter monitor
- Thyroid blood test
- Echocardiogram
Next steps
- Check your pulse during an episode
- Record episodes on a smartwatch or phone if possible
- Reduce caffeine and alcohol
- Book a doctor visit if episodes recur
Frequently asked questions
Are palpitations dangerous?
Most are harmless. Some rhythms, such as atrial fibrillation, raise stroke risk or cause fainting. That is why recurring palpitations deserve a check.
Can a smartwatch detect AFib?
Some watches can flag an irregular rhythm. They are useful for catching episodes. A doctor still needs a medical ECG to confirm the diagnosis.
What if my ECG is normal?
Your rhythm may have been normal at the time of the test. Wearing a monitor for days or weeks gives a better chance of recording an episode.
Medically reviewed by The Curaventa Team. Last updated 2026-10-24. General information, not medical advice. Medical editorial board · Editorial policy · How we get prices
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