What is paroxysmal supraventricular tachycardia?

Answer 1

sally,

It is a sudden, brief acceleration of the top two chambers of the heart. It used to be called "paroxysmal atrial tachycardia," but the name has been changed.

It comes in two basic forms, "focal" and "re-entrant." The focal type means that an extra "circuit" in the electrical connections inside the heart exists. There are a few spots where this happens most commonly, such as at the pulmonary veins. They can cause a burst of electrical "firings" that will speed up the atria. If it is really bothersome, they usually need to be zapped with radio-frequency energy and killed. Then the heart will act normally.

The other one, the "re-entrant" kind, has an extra pathway or two from either of the two nodes in the right atrium, usually the sinus node high in the chamber. The signal started by the sinus node travels a short distance toward teh other node, the AV (atriaoventricular) node, but part of the signal flows into this other pathway and goes back to the sinus node where it triggers another signal for another beat, and so the two atria beat several times as fast as they normally do.

This goes on for a brief time, then quits.

The reason this happens is because the heart electrically is just two chambers. The atria beat together, and the ventricles beat together. The signal starts high in the right atria, in the SA (sinoatrial) node, the "sinus" node, which acts as the heart's pacemaker. The signal then travels down to the AV node, which is the heart's gatekeeper, allowing some signals through, but not others. This is when the atria beat. Then the signal travles through the only path between the atria and the ventricles, the Bundle of His, and then down the Purgenje Fibers down the septum between the ventricles, and then around the apex (the bottom, the point) of the heart, and partway back up the sides ofhte ventricles. This is when they beat.

It doesn't take much electricity to get the job done, just a microvolt or less, but it all starts in the sinus node. If it is disturbed, the beating of the heart will become abnormal. In the case of PSVT, it is usually benign. Most of us experience that, and it causes no problem.

There are conditions, however, that could feel like PSVT that aren't, and so if you are experiencing PSVT regularly, and if it lasts longer than a minute, you might want your doctor to have a look. An ekg tracing that catches it will tell immediately if it is PSVT or atrial flutter, a condition that you would want treated or at least watched for a time by a professional.

Good luck.

Answer 2

Paroxysmal = it comes and goes
Supraventricular = the heartbeat begins above the ventricles (in the top part of the heart)
Tachycardia = fast heartbeat

It is an arrhythmia, with a very fast heartbeat, usually over 160 beats per minute. It can be symptomatic, causing chest pain or shortness of breath, but is frequently just annoying. It can be treated with medication, vagal manuevers (coughing, valsalva, carotid massage) or, if the patient is unstable, by cardioversion (electric shock with the paddles like you see on TV)

Learn more here:
http://www.merck.com/mmhe/sec03/ch027/ch027d.html

(The post above mine is incorrect - it does not originate in the ventricles. That is ventricular tachycardia, which is serious and can be fatal. Entirely different scenario.)

Answer 3

PSVT- It is an abnormal heart rythum. Starts in the upper chambers of the Heart (atria).