Supraventricular tachycardia (SVT), also called paroxysmal supraventricular tachycardia, is defined as an abnormally fast heartbeat. It’s a broad term that includes many forms of heart rhythm problems (heart arrhythmias) that originate above the ventricles (supraventricular) in the atria or AV node. A normal heart rate is 60 to 100 beats per minute. A heart rate of more than 100 beats per minute is called a tachycardia (tak-ih-KAHR-dee-uh). This occurs when the electrical impulses that coordinate your heartbeats don’t work properly. It may feel like a fluttering or racing heart.
Most people with rare episodes of supraventricular tachycardia live healthy lives without restrictions or interventions. For others, treatment and lifestyle changes can often control or eliminate rapid heartbeats. Supraventricular tachycardia may come and go suddenly, with stretches of normal heart rates in between. Symptoms may last anywhere from a few minutes to a few days, and some people have no symptoms at all. Supraventricular tachycardia becomes a problem when it occurs frequently and is ongoing, particularly if you have heart damage or other coexisting medical problems. Signs and symptoms of supraventricular tachycardia may include: Fluttering in the chest, Rapid heartbeat (palpitations), Shortness of breath, Lightheadedness or dizziness, Sweating, A pounding sensation in the neck, Fainting (syncope) or near fainting.