An episode of supraventricular tachycardia (SVT) occurs when abnormal electrical impulses suddenly start in the upper chambers of the heart, and override the heart’s natural rhythm.
SVT is sometimes called paroxysmal supraventricular tachycardia (PSVT). Paroxysm means a sudden temporary disturbance of heart rhythm.
PSVT is usually caused by a short circuit in the electrical system of the heart, which causes an electrical signal to travel rapidly and continuously around in a circle, forcing the heart to beat each time it completes the circuit.
Another type of SVT is called Wolff-Parkinson-White syndrome, where an abnormal electrical connection occurs between the atria (upper heart chambers) and ventricles (lower heart chambers). People with Wolff-Parkinson-White syndrome are born with a strand of extra muscle tissue between these chambers. This produces a short circuit, which causes the fast heartbeat.
SVT triggers
SVT is usually triggered by extra heartbeats (ectopic beats), which occur in all of us but may also be triggered by:
- some medications, including asthma medications, herbal supplements and cold remedies
- drinking large amounts of caffeine or alcohol
- stress or emotional upset
- a change in posture
- smoking lots of cigarettes
Comments are closed.