Supraventricular tachycardia (SVT) is a fast heart rhythm that starts above the heart’s ventricles. It can feel scary — sudden racing pulse, fluttering, or a thumping in your chest. Often episodes start and stop on their own, but you don’t have to guess what to do when it happens.
Most people notice a sudden fast heartbeat, sometimes 150–250 beats per minute. You might feel lightheaded, short of breath, shaky, or sweaty. Some people have chest tightness or fainting. Symptoms can last seconds, minutes, or longer. If you’ve had palpitations that come out of nowhere, SVT is one common cause.
If you have chest pain, fainting, severe shortness of breath, or confusion, call emergency services now. Those signs mean your body isn’t getting enough oxygen. If episodes are less severe but happen often, make an appointment with your doctor to get tested.
Your doctor will usually start with a resting ECG. If the episode isn’t happening in clinic, a Holter monitor or event recorder can catch it later. In some cases an electrophysiology study (EP study) finds the exact spot causing the fast rhythm. That helps plan treatment.
Short-term fixes you can try: vagal maneuvers. Simple moves like the Valsalva maneuver (bearing down) or splashing cold water on your face can sometimes stop SVT by triggering your body’s natural vagus nerve reflex. Don’t force anything that causes pain. If a vagal trick doesn’t work and you’re feeling worse, seek care.
Medicines doctors use include beta-blockers, calcium channel blockers, and sometimes antiarrhythmic drugs. In emergencies, a drug called adenosine is often given in hospital to reset the rhythm quickly. These meds can help control or stop episodes, but they may have side effects and need follow-up.
Catheter ablation is a one-time procedure that targets and destroys the tiny heart tissue causing SVT. It’s done by an electrophysiologist and often cures SVT or greatly reduces episodes. Many people choose ablation when attacks are frequent or lifestyle-limiting.
Want to reduce triggers? Cut back on caffeine, energy drinks, nicotine, and stimulants. Stay hydrated, manage stress, and avoid heavy alcohol binges. Track when attacks happen — noting food, drinks, sleep, and stress can reveal patterns to discuss with your doctor.
Living with SVT means having a plan: know your warning signs, practice a safe vagal maneuver if advised, carry ID that says you have SVT if you have severe episodes, and keep follow-up with a cardiologist. If you aren’t sure what to do next, ask for an evaluation — a short clinic visit can set a clear path forward.
