Supraventricular Tachycardia

Supraventricular tachycardia or SVT is an abnormally quick heartbeat that originates above the ventricles, the lower two chambers of the heart. SVT is a general, catchall term for arrhythmias in the atria, the upper chambers of the heart, or the AV node. SVT is predominantly caused by abnormal electrical focus in the upper chambers of the heart, an abnormal electrical pathway called WPW or anatomic variation at the electrical junction.

This is the most common arrhythmia seen predominantly in young people with exceptions at later ages. When SVT presents in infants and young children, it can be hard to differentiate these symptoms from other possible disorders, often delaying a diagnosis.

Symptoms of SVT

Symptoms vary from palpitations or flutters to chest pain, shortness of breath, dizziness and syncope (unexplained fainting) due to low blood pressure from fast heart rate with this arrhythmia. This is a non-life-threatening arrhythmia and typically presents with otherwise normal heart function.

Consequences of Untreated SVT

It is important to see a doctor if you or your child experience the symptoms of SVT. While the condition itself is not life-threatening, untreated arrhythmias can cause damage and weakening to the heart over time which can lead to eventual heart failure. Any other heart or general health issues can create complicating factors. Those with diagnosed SVT should also be aware that passing out or fainting caused by their arrhythmia can lead to significant injury and should exercise great care when performing activities.

The Diagnostic Process

Diagnosing SVT is similar to the process of diagnosing any arrhythmia. Most likely, the process will begin at the primary care physician’s office, or if the patient suffers from congenital heart issues, they may be referred directly to their cardiologist or electrophysiologist.

SVT is a paroxysmal or intermittent arrhythmia and as such may not always show up on an Electrocardiogram/EKG or echocardiogram. A stress test or tilt table test may be employed to induce symptoms and monitor heart activity to further understand how the heart and nervous system react to certain physical stressors.

External Holter monitors (constant monitoring) or event monitors (patient induced monitoring) can record the electrical activity of the heart over a number of days, the results of which can be analyzed to understand more about the arrhythmia.

An EP study, using minimal invasive catheter technology and advanced mapping techniques can be used to accurately map the electrical patterns of the heart and even trigger an arrhythmia.

Treatment for SVT

Talk to your doctor about treatment options best suited to your clinical situation. When possible and appropriate, we recommend a stepped approach to care starting with lifestyle changes and followed by medication. However, in those who have not seen relief, cardiac catheter ablation can cure this condition with the likelihood of not needing further medication. Indeed, catheter ablation can be performed during the diagnostic EP study if there is evidence to support its efficacy for the particular circumstance.