Supraventricular Tachycardia (SVT)
Sudden racing heart episodes
Summary
Supraventricular tachycardia is a sudden fast heartbeat that starts in the upper chambers of your heart. Episodes can begin and stop without warning, sometimes while you are resting. Your heart may race between 150 and 250 beats per minute. Most people feel a pounding or fluttering chest, lightheadedness, or shortness of breath, and sometimes chest discomfort. For most people SVT is not dangerous, but a first episode should always be checked by a cardiologist.
Triggers are not always clear. Caffeine, alcohol, stress, and hard exercise set it off for some people. Others notice no pattern at all. Because episodes are brief, a standard ECG in the office can look normal. We often send you home with a wearable monitor for days or weeks to catch the rhythm during everyday life.
Many episodes stop on their own or with vagal maneuvers your care team teaches you. When episodes are frequent or disruptive, beta-blockers or calcium channel blockers reduce them. Catheter ablation, a minimally invasive procedure done by an electrophysiologist, cures most types of SVT and is a strong option when medication is not enough or not wanted.
During an episode
Only if your care team has shown you how: bear down like a bowel movement, or blow hard against a closed mouth and nose. Ask us which maneuver is right for you.
When to call us
- •Call 911 for fainting, severe chest pain, or a racing heart that will not slow
- •Otherwise call us at 856-546-3003 to review symptoms and plan next steps
Questions to ask your doctor
- 1.What type of SVT do I have?
- 2.Which vagal maneuver is right for me, and how do I do it safely?
- 3.Do I need a wearable monitor to catch an episode?
- 4.Would medication or catheter ablation be better for me?
- 5.Should I cut back on caffeine or alcohol?
Learn more
Educational resources from the American College of Cardiology's CardioSmart program.