Overview
SVT causes a fast heartbeat that starts and stops suddenly.
Triggers include caffeine, stress, and alcohol.
When to get medical care
Causes
Causes include SVT and other heart rhythm problems.
OwieClear has pages on 2 conditions that can cause racing heart that starts and stops suddenly. Each shows how soon to get care.
Common causes
- SVT (sudden fast heart rhythm)See a doctor if it doesn't get better
Episodes of a very fast heartbeat that start and stop suddenly, like a switch, often with a pounding feeling, dizziness, or shortness of breath.
- Wolff-Parkinson-White syndrome (WPW)Often needs care today
An extra electrical pathway in the heart present from birth.
What you can do at home
- Try bearing down like having a bowel movement.
- Limit caffeine.
Medicines
Medicines or ablation can help.
At the doctor
An ECG during an episode helps.
Questions you may be asked
- Episodes
- Triggers
The exam
A heart exam.
Tests
- ECG
- Heart monitor
Prevention
Reduce triggers.
- Limit caffeine and alcohol
Check your symptoms
Most symptoms have more than one possible cause. The symptom checker looks at all of your symptoms together, plus your age, and shows how soon to get care.
Sources
Last updated 2026-11-13.