Video coming soon — Dr. Luni explains svt in plain language
What is SVT?
SVT stands for supraventricular tachycardia — a rapid heart rhythm that originates above the ventricles (the lower pumping chambers). The most common types are AVNRT (AV nodal reentrant tachycardia) and AVRT (AV reentrant tachycardia, which involves an accessory pathway).
SVT typically starts suddenly, causes the heart to beat at 150-250 beats per minute, and stops abruptly — often described as a light switch turning on and off. Episodes can last seconds or hours.
What does SVT feel like?
- Sudden onset of very rapid, regular pounding in the chest
- Palpitations that start and stop abruptly
- Neck pulsations
- Shortness of breath
- Lightheadedness or dizziness
- Rarely, fainting
- Anxiety during episodes
How is SVT treated?
In the moment (acute termination)
SVT episodes can sometimes be stopped with vagal maneuvers — bearing down as if straining for a bowel movement, or splashing cold water on your face. If that does not work, a medication called adenosine given intravenously in an emergency room will almost always terminate the episode.
Long-term: catheter ablation
Catheter ablation is the definitive treatment for SVT, with cure rates exceeding 95% for the most common forms. The procedure involves inserting thin catheters into the heart through the groin veins, mapping the abnormal circuit, and delivering energy (usually radiofrequency) to eliminate it. Most patients go home the same day and never have SVT again.
Medications
Beta-blockers or calcium channel blockers can reduce the frequency and severity of SVT episodes but do not cure the underlying problem. Many patients prefer ablation to years of daily medication.
SVT is one of the most satisfying conditions to treat in electrophysiology — it is common, well understood, and curable in the vast majority of patients with a single outpatient procedure.