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Alternative Names
PSVT; Supraventricular tachycardiaDefinition Return to top
Paroxysmal supraventricular tachycardia (PSVT) is an occasional rapid heart rate. "Paroxysmal" means from time to time.
Causes Return to top
Normally, the chambers of the heart (atria and ventricles) contract in a coordinated manner. The contractions are caused by an electrical signal that begins in an area of the heart called the sinoatrial node (also called the sinus node or SA node). The signal moves through the upper heart chambers (the atria) and tells the atria to contract.
PSVT starts with events taking place above the lower heart chambers (ventricles). PSVT can be initiated in the SA node, in the upper heart chambers (atria), in the atrial conduction pathways, or other areas.
PSVT can occur with digitalis toxicity and conditions such as Wolff-Parkinson-White syndrome.
The condition occurs most often in young people and infants.
The following increase your risk for PSVT:
Symptoms Return to top
Additional symptoms that may be associated with this condition:
Note: Symptoms may start and stop suddenly, and can last for a few minutes or several hours. A PSVT lasting more than half of the day is considered an incessant PSVT.
Exams and Tests Return to top
A physical examination during a PSVT episode will show a rapid heart rate.
The heart rate may be 150 to 250 beats per minute (bpm). In children, the heart rate tends to be very high. There may be signs of poor blood circulation such as light headedness. Between episodes of PSVT, the heart rate is normal (60 to 100 bpm).
An ECG during symptoms shows PSVT. An electrophysiology study (EPS) is often necessary for an accurate diagnosis and to recommend the best treatment.
Because of the sporadic nature of the PSVT, its diagnosis may require 24-hour Holter monitoring. For longer recording periods, a "loop recorder" (with computer memory) is used.
Treatment Return to top
If you do not have symptoms, PSVT may not require treatment.
If symptoms occur or if you have another heart disorders, treatment may be necessary.
If you have an episode of PSVT, a technique called the Valsalva maneuver can be used to interrupt the fast heartbeat. Hold your breath and strain, as if you were trying to have a bowel movement, or cough while sitting with your upper body bent forward.
Splashing ice water on the face has been reported by some people as helpful.
Emergency treatment of PSVT may include:
Long-term treatment of PSVT may include:
Outlook (Prognosis) Return to top
PSVT is generally not life threatening, unless other heart disorders are present.
Possible Complications Return to top
The main complication is an increased risk of heart failure.
When to Contact a Medical Professional Return to top
Call your health care provider if:
Prevention Return to top
Avoid??smoking, caffeine, alcohol, and illicit drugs. Medications used to treat the disorder may be given as a preventive (prophylactic) treatment in people at a high risk or who have had previous episodes of PSVT.
References Return to top
Olgin JE, Zipes DP. In: Specific Arrhythmias: Diagnosis and Treatment. In: Libby P, Bonow RO, Mann DL, Zipes DP, eds. Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine. 8th ed. St. Louis, Mo: WB Saunders; 2007: chap. 35.
Update Date: 5/12/2008 Updated by: Larry A. Weinrauch, MD, Assistant Professor of Medicine, Harvard Medical School, and Private practice specializing in Cardiovascular Disease, Watertown, MA. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.
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