ECG findings
P waves
may be antegrade, retrograde, or absent depending on depolarization of the atrial relative to the ventricles
QRS complexes
Narrow in the absence of aberrancy
May be distinguished from AVNRT via Adenosine administration
If JET is present, atrial depolarization will briefly terminate and reveal AV dissociation
If AVNRT is present, conversion to sinus rhythm will likely occur
Avoid administration in the setting of aberrancy
JET will concomitant 3 degree AVB is rare
Consider JET underlying causes to include
Electrolyte abnormalities
Acidosis
Cardiovascular surgery within 24-48 hrs
P waves
may be antegrade, retrograde, or absent depending on depolarization of the atrial relative to the ventricles
QRS complexes
Narrow in the absence of aberrancy
may be antegrade, retrograde, or absent depending on depolarization of the atrial relative to the ventricles
Narrow in the absence of aberrancy
If JET is present, atrial depolarization will briefly terminate and reveal AV dissociation
If AVNRT is present, conversion to sinus rhythm will likely occur
Avoid administration in the setting of aberrancy
JET will concomitant 3 degree AVB is rare
Electrolyte abnormalities
Acidosis
Cardiovascular surgery within 24-48 hrs
Junctional tachycardia
Regular
Wide-complex tachycardia
AV Node Independent
Narrow-complex tachycardia
Sinus tachycardia
Third degree AV block
Atrial tachycardia 