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A paroxysmal supraventricular tachycardia is a fast heart rhythm (arrhythmia) that occurs in the upper chambers of the heart (atria). These types of arrhythmias tend to start and stop randomly and without warning and are due to an “electrical short circuit” in the heart. There are three different types of paroxysmal supraventricular tachycardia:
AV node reentrant tachycardia (AVNRT) – With this type of paroxysmal supraventricular tachycardia, an electrical short circuit forms around the AV node (the electrical bridge between the atrium (top chambers of your heart) and the ventricle (bottom chambers of your heart). This causes an extra impulse to go around the short circuit and can cause your heartbeat to increase to 120, or maybe even over 200, beats per minute. This is the most common type of paroxysmal supraventricular tachycardia.
Wolff-Parkinson-White syndrome (WPW) – This type of paroxysmal supraventricular tachycardia is caused by an accessory pathway that individuals are born with. The accessory pathway is an abnormal muscle fiber bridge that spans across one of the heart valves and connects the bottom and top chambers of the heart. This extra pathway may cause the heart to beat too soon and too quickly.
Atrial tachycardias – The least common type of paroxysmal supraventricular tachycardia is an atrial tachycardia. These occur when the heart’s electrical impulses come from the atrium of the heart rather than the normal pacemaker of the heart, the SA node.
Other types of supraventricular tachycardia include atrial fibrillation and atrial flutter.
Symptoms of paroxysmal supraventricular tachycardia include the sensation of a racing heartbeat that starts and stops abruptly. Other symptoms include shortness of breath, chest discomfort and dizziness. If you experience a drop in your blood pressure, you may lose consciousness.
Ohio State’s electrophysiology program is the largest program in Ohio and one of the top three in the nation. Its staff has extensive experience in managing a wide spectrum of heart rhythm problems. The Ross Heart Hospital also has consistently been one of the largest ablation centers in the country, utilizing physician experience coupled with advanced mapping and ablation technology to manage the wide spectrum of heart rhythm problems.
The first step in the diagnosis of paroxysmal supraventricular tachycardia is a medical history and physical examination by your electrical heart doctor (called an electrophysiologist). Many times, the first diagnosis of a paroxysmal supraventricular tachycardia is when a patient seeks urgent help to treat an episode of paroxysmal supraventricular tachycardia. An electrocardiogram (EKG/ECG) obtained at the time of the heart rhythm problem will confirm the diagnosis of paroxysmal supraventricular tachycardia. Based on your symptoms, your electrophysiologist may also recommend other tests such as:
Holter monitor – A portable, battery-operated EKG/ECG that is worn for a day or two and provides your physician with continuous data about the electrical activity of your heart.
Cardiac event monitor – A small device that is worn for longer periods of time (weeks to months) to record heart rhythms.
Electrophysiology (EP) study – An invasive test that measures the electrical system of the heart to help diagnose and treat paroxysmal supraventricular tachycardia.
If your paroxysmal supraventricular tachycardia episodes are short, infrequent and occur with minimal symptoms, you may not need treatment. If your episode lasts for a longer period of time without stopping, you may be given medications in an emergency room setting to stop the arrhythmia. If you have been to the emergency room for paroxysmal supraventricular tachycardia, have frequent episodes or severe symptoms, your doctor will likely recommend treatment such as medications or catheter ablation.
Antiarrhythmic medications – Medications that are specifically designed to help restore and to maintain normal rhythm.
Catheter ablation – A technique to permanently eliminate the source of paroxysmal supraventricular tachycardia by using radiofrequency energy.
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