There are two types of supraventricular tachycardias (SVT):
A.V. Nodal Reentry Tachycardia (AVNRT)
A.V. nodal reentry tachycardia (AVNRT) is an electrical loop or circuit around the A.V. node. During AVNRT, the electrical impulses travel upward and downward, causing a fast heart beat.
Wolff-Parkinson White Syndrome
People with Wolff-Parkinson White Syndrome (WPW) have an accessory (extra) electrical pathway. This pathway bypasses the normal electrical conduction in the heart. The extra pathway conducts electricity faster than the normal path. It sometimes shows itself as a "delta wave" on the EKG. WPW often results in a very rapid heart rate. In both types of SVT, the extra electrical pathways are present at birth. However, the tachycardia may begin at any age.
What are the Symptoms of Supraventricular Tachycardia?
"SVT" may cause a variety of symptoms, depending on how fast the heart is beating and on your age and physical condition. Symptoms may include one or all of the following: palpitations, rapid heart rate, flushing/warm feeling, lightheadedness or dizziness, sweating, nausea, shortness of breath, chest tightness, near fainting or actual fainting.
Is there Testing for Supraventricular Tachycardia? Your doctor will want to know about your symptoms. They will also want you to have an electrocardiogram (EKG) and an electrophysiology study (an EPS).
What is the Treatment for Supraventricular Tachycardia?
During the EP Study, the doctor may try to make your heart beat fast. This is done through a catheter inside your heart. Drugs may be given through a vein in your arm. These drugs help bring on your arrhythmia. During the EP study the doctor will use special catheters to "map" the inside of your heart chambers. "Mapping" is done to find the exact spot causing your arrhythmia and the type of "SVT" you have. Once the type and location of your arrhythmia is found, your doctor can then prescribe the best treatment plan for you.
Treatment may involve one or more of the following: medication, ablation (done during another EP study) or surgery to remove the "extra" pathway (needed less frequently).