Key Points
2
• CTI– dependent
atrial flutter:
reverse typical
Macroreentrant AT that propagates around in the direction
reverse that of typical atrial flutter. Flutter waves typically
appear positive in the inferior leads and negative in V1. is
type of atrial flutter is also referred to as "reverse typical" atrial
flutter or "clockwise typical atrial flutter."
• Atypical or non-
CTI– dependent
atrial flutter
Macroreentrant ATs that do not involve the CTI. A variety of
reentrant circuits may include reentry around the mitral valve
annulus or scar tissue within the le or right atrium. A variety of
terms have been applied to these arrhythmias according to the
reentry circuit location, including particular forms, such as "LA
flutter" and "LA macroreentrant tachycardia" or incisional atrial
reentrant tachycardia due to reentry around surgical scars.
Junctional
tachycardia
A nonreentrant SVT that arises from the AV junction
(including the His bundle).
Atrioventricular
nodal reentrant
tachycardia
(AVNRT)
A reentrant tachycardia involving 2 functionally distinct
pathways, generally referred to as "fast" and "slow" pathways.
Most commonly, the fast pathway is located near the apex of
Koch's triangle, and the slow pathway inferoposterior to the
compact AV node tissue. Variant pathways have been described,
allowing for "slow-slow" AVNRT.
• Typical AVNRT AVNRT in which a slow pathway serves as the anterograde limb
of the circuit and the fast pathway serves as the retrograde limb
(also called "slow-fast AVNRT").
• Atypical AVNRT AVNRT in which the fast pathway serves as the anterograde
limb of the circuit and a slow pathway serves as the retrograde
limb (also called "fast-slow AV node reentry") or a slow pathway
serves as the anterograde limb and a second slow pathway serves
as the retrograde limb (also called "slow-slow AVNRT").
Accessory pathway For the purpose of this guideline, an accessory pathway
is defined as an extranodal AV pathway that connects the
myocardium of the atrium to the ventricle across the AV groove.
Accessory pathways can be classified by their location, type of
conduction (decremental or nondecremental), and whether
they are capable of conducting anterogradely, retrogradely, or
in both directions. Of note, accessory pathways of other types
(such as atriofascicular, nodo-fascicular, nodo-ventricular, and
fasciculoventricular pathways) are uncommon.
• Manifest accessory
pathways
A pathway that conducts anterogradely to cause ventricular
pre-excitation pattern on the ECG.
• Concealed
accessory pathway
A pathway that conducts only retrogradely and does not affect
the ECG pattern during sinus rhythm.
Table 1. Relevant Terms and Definitions (cont'd)
Arrhythmia/Term Definition
