Classification of AVNRT: an unresolved entity.
The classification of AVNRT is based on HA and VA interval. Typical
AVNRT is diagnosed in presence of HA ≤70 ms OR VA interval ≤60 ms and
HA>70ms or VA >60ms is required to diagnose
atypical AVNRT. This might be fallacious in some clinical situations.
The septal VA and the “shortest” VA may be also different depending on
clinical scenario .