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Re-entrant atrioventricular node tachycardia — Clinical Guidelines

Overview

Re-entrant atrioventricular (AV) node tachycardia involves abnormal electrical circuits within the AV node, leading to rapid heart rates without the involvement of accessory pathways. It is characterized by dual AV nodal pathways facilitating re-entry mechanisms 1 4.

Diagnosis

Electrocardiogram (ECG) findings: Wide QRS complexes, variable AV conduction, and tachycardia 3.

Electrophysiological study: Essential for confirming the diagnosis and differentiating from other tachycardias 1 3.

His bundle recordings: Useful in identifying conduction patterns indicative of AV node re-entry 9.

Rate-dependent retrograde conduction: May be observed in some cases, particularly with accessory pathways 2.

Management

Catheter ablation: Selective radiofrequency ablation of the slow AV nodal pathway is the first-line treatment 1 4.

Facilitation techniques: Intravenous isoproterenol can improve catheter stability and facilitate ablation in cases of incessant tachycardia 1.

Medications: Verapamil and propranolol may be used to control heart rate but do not address the underlying mechanism 8.

Pacemaker therapy: Considered in cases with high risk of AV block post-ablation or in refractory cases 5.

Special Populations

Elderly: Catheter ablation remains effective but requires careful assessment of procedural risks 1.

Comorbidities: Patients with structural heart disease may have increased risk of complications; careful monitoring is essential 5.

Key Recommendations

Primary treatment with catheter ablation of the slow AV nodal pathway for definitive management (Evidence: Strong 1 4).

Use of isoproterenol during ablation can enhance procedural success in incessant cases (Evidence: Moderate 1).

Consider dual-demand pacing as an adjunctive therapy for refractory cases, particularly in Wolff-Parkinson-White syndrome (Evidence: Weak 8).

Close monitoring for AV block post-ablation, especially in high-risk patients (Evidence: Expert opinion).

References

1 Wang NC, Razak EA, Jain SK, Saba S. Isoproterenol facilitation of slow pathway ablation in incessant dual atrioventricular nodal nonreentrant tachycardia. Pacing and clinical electrophysiology : PACE 2012. link 2 Rordorf R, Vicentini A, Petracci B, Landolina M. Intermittent rate-dependent retrograde conduction over a concealed atrioventricular accessory pathway: what is the mechanism?. Europace : European pacing, arrhythmias, and cardiac electrophysiology : journal of the working groups on cardiac pacing, arrhythmias, and cardiac cellular electrophysiology of the European Society of Cardiology 2009. link 3 Tanner H, Sakata T, Delacrétaz E. Wide QRS-complex tachycardia with variable VA-conduction: what is the mechanism?. Europace : European pacing, arrhythmias, and cardiac electrophysiology : journal of the working groups on cardiac pacing, arrhythmias, and cardiac cellular electrophysiology of the European Society of Cardiology 2008. link 4 Verdino RJ, Iuliano S, Tracy CM. Successful ablation of a nonreentrant dual atrioventricular nodal tachycardia. Journal of interventional cardiac electrophysiology : an international journal of arrhythmias and pacing 1997. link 5 Chen IC, Yeh SJ, Wen MS, Wang CC, Lin FC, Wu D. Progression to complete atrioventricular block in a patient with bundle branch re-entry tachycardia. Journal of electrocardiology 1995. link80264-x) 6 Littmann L, Svenson RH. Concealed reentry: a mechanism of atrioventricular nodal alternating Wenckebach periodicity. Circulation 1982. link 7 Wilkinson PR, Desai J, Hollister J, Gonzalez R, Abbott JA, Scheinman MM. Electrophysiologic effects of disopyramide in patients with atrioventricular nodal dysfunction. Circulation 1982. link 8 Curry PV, Rowland E, Krikler DM. Dual-demand pacing for refractory atrioventricular re-entry tachycardia. Pacing and clinical electrophysiology : PACE 1979. link 9 Castellanos A, Sung RJ, Berkovits BV, Alatriste VM, Myerburg RJ. His bundle recordings in atrioventricular nodal alternating Wenchebach periods ending in 5:1 atrioventricular block coexisting with paroxysmal atrioventricular nodal block. Chest 1978. link 10 Weisfogel GM, Batsford WP, Paulay KL, Josephson ME, Ogunkelu JB, Akhtar M et al.. Sinus node re-entrant tachycardia in man. American heart journal 1975. link90316-6)

Re-entrant atrioventricular node tachycardia