Paroxysmal supraventricular tachycardia (PSVT) is an occasional rapid heart rate. "Paroxysmal" means from time to time.
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:
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.
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 lightheadedness. 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.
If you do not have symptoms, PSVT may not require treatment.
If symptoms occur or if you have another heart disorder, 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:
PSVT is generally not life threatening, unless other heart disorders are present.
The main complication is an increased risk of heart failure.
Call your health care provider if:
AvoidÃ‚Â 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.
PSVT; Supraventricular tachycardia