Paroxysmal Atrial Tachycardia


Atrial 160-250/min: may conduct to ventricles 1:1, or 2:1, 3:1, 4:1 into the presence of a block.

P wave

Morphology usually varies from sinus


Normal (unless associated with aberrant ventricular conduction).


P-R interval depends on the status of AV conduction tissue and atrial rate: may be normal, abnormal, or not measurable.

PAT also known as Paroxysmal Supraventricular Tachycardia (PSVT) may occur in the normal as well as diseased heart.

This rhythm is often transient and usually requires no treatment.

Frequent symptomatic episodes may require surgical intervention. When an accessory conduction pathway can be demonstrated, interventional surgery to ablate the accessory conduction pathway can be curative. Click here for a more complete description of the PSVT mechanism.