What is supraventricular tachycardia?

Supraventricular tachycardia (SOO-prah-ven-TRIK-u-lar tak-eh-KAR-de-ah), or SVT, is when your heart beats faster than it should. It is not normal for your heart to beat too fast without a reason, like during heavy exercise.

What are the symptoms?

You might feel fluttering or tightness in your chest. You may also be short of breath or lightheaded. The symptoms of SVT are similar to symptoms of anxiety, so it is important to talk to your doctor to find out if you have SVT. It is also important to contact your doctor right away if your symptoms last longer than a couple of minutes, if you have them often, if you get new symptoms, or if the symptoms are bad enough that you think you may pass out.

How is it diagnosed?

SVT is usually diagnosed using a test called an electrocardiogram, or ECG (also called an EKG). An ECG can be done in your doctor's office or a hospital. However, the ECG may not work if your heart is not beating fast at the time of the test.

How is it treated?

SVT can be treated in two ways: (1) when the heart is beating fast, and (2) before the heart beats too fast, to prevent it from happening. Your doctor might recommend medicine or an electric shock to slow your heartbeat to a normal rate.

You might be able to stop your fast heartbeat with a technique called the Valsalva maneuver, which can be done by holding your breath and straining like you are trying to have a bowel movement, or by coughing while sitting with your upper body bent forward. You could also try putting your face in ice water for a few seconds. You should talk to your doctor before trying any of these options.

What if it keeps happening?

You may need to see a heart doctor. He or she may have you record your heartbeat at home using a Holter monitor or cardiac event recorder. You may need medicine, surgery, or a pacemaker.

How can I prevent SVT?

Avoid or limit your use of alcohol, tobacco, caffeine, and street drugs, because these can sometimes cause SVT.