Atriventricular Reentry Tachycardia (AVRT) - ORT vs ART

Orthodromic Reentry Tachycardia - conduction via AV node-His-Purkinje system to the ventricle, and retrograde conduction via accessory pathway.

Antidromic Reentry Tachycardia (ART) - antegrade conduction via accessory pathway to the ventricle, and retrograde conduction via His-Purkinje system and AV node.