Atypical Atrioventricular Node Reciprocating Tachycardia Masquerading as Tachycardia Using a Left-Sided Accessory Pathway

Abstract

Atypical AVNRT with eccentric retrograde left-sided activation was demonstrated in 6% of all patients with AVNRT masquerading as tachycardia using a left-sided accessory pathway. Ablation of the slow pathway at the posterior aspects of the right atrial septum resulted in a cure in these patients.

Patient with Atrioventricular Node Reentrant Tachycardia with Eccentric Retrograde Left-sided Activation. Treatment with Radiofrequency Catheter Ablation.

“…[5][6][7] In some cases with such connection, especially to the left atrium, it is likely that atypical AVNRT is induced by eccentric retrograde left-sided activation. 8,10,14) In the present electrophysiologic study, double observations of the jump-up phenomenon suggest that triple AV nodal pathways are present. About the retrograde left-sided activation, long and decremental conduction negates the participation of the accessory pathway recognized in concealed WPW syndrome.…”

“…[5][6][7] Hwang, et al have reported that AVNRT with left-sided activation, which may occur with such a connection, is relatively rare. 8) In this report, we describe a patient with AVNRT caused by a left-sided pathway that was confirmed by the success of radiofrequency catheter ablation.…”

“…Therefore, this SVT represents AVNRT with eccentric retrograde left-sided activation. 8) In addition, this AVNRT is a slow-slow form, because the retrograde VA interval is > 60 msec and the AH interval is greater than the HA interval during reciprocating tachycardia. 8,15) It has been reported that this type of AVNRT is seen in only 6 % of all patients with AVNRT.…”

“…8) In addition, this AVNRT is a slow-slow form, because the retrograde VA interval is > 60 msec and the AH interval is greater than the HA interval during reciprocating tachycardia. 8,15) It has been reported that this type of AVNRT is seen in only 6 % of all patients with AVNRT. 8) Hwang, et al have reported successful radiofrequency ablation of the slow pathway in the posterior region of the right atrial septum, 8) as in the present case.…”

“…As described previously, 8) an electrophysiologic study was performed while the patient was fasting and not sedated. All antiarrhythmic medications had been discontinued for 2 weeks.…”