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Nonparoxysmal AV nodal tachycardia — Clinical Guidelines

Overview

Atrioventricular nodal reentry tachycardia (AVNRT) is a common form of supraventricular tachycardia characterized by reentry circuits involving dual pathways within the atrioventricular (AV) node, leading to rapid heart rates without preceding symptoms like palpitations or syncope. 1 8 11

Diagnosis

Clinical Presentation: Narrow QRS complex tachycardia, often induced by exercise or vagal maneuvers.

Electrophysiological Study: Demonstrates typical AVNRT with slow-fast or fast-slow reentry patterns.

Electrocardiogram (ECG) Findings: Presence of delta waves, PR interval prolongation, and characteristic tachycardia cycle lengths.

Holter Monitoring: Useful for detecting intermittent episodes in asymptomatic patients.

Echocardiography: To rule out structural heart disease.

Correlation with PR Interval: Prolonged PR interval in sinus rhythm may predict AVNRT susceptibility. 5

Management

First-Line Treatment: Radiofrequency catheter ablation targeting the slow pathway.

Adjunctive Pharmacological Therapy: Antiarrhythmic drugs like adenosine for acute termination (dose: 6-12 mg IV bolus).

Ablation Techniques: Zero-fluoroscopy approach shows high efficacy and safety 1 2.

Cryoablation: An alternative method with favorable outcomes, though residual jumps may influence long-term results 4.

Post-Ablation Monitoring: Periodic follow-up ECGs to assess for AV block.

Procedure Duration: Abbreviated procedures can be effective without compromising long-term success 6.

Special Populations

Pediatrics: Cryoablation and zero-fluoroscopy RF ablation are feasible and safe 2.

Elderly: Increased risk of AV block; careful monitoring of electrophysiological markers like junctional beats is advised 3.

Comorbidities: Patients with prior valve surgery may present with unique challenges, such as prolonged PR intervals, requiring tailored approaches like cryotherapy for fast pathway ablation 5.

Key Recommendations

Primary Treatment with Catheter Ablation: Radiofrequency ablation targeting the slow pathway is highly effective and safe for AVNRT (Evidence: Strong 1 8).

Consider Zero-Fluoroscopy Techniques: Utilize zero-fluoroscopy approaches for RFCA to minimize radiation exposure without compromising efficacy (Evidence: Moderate 1 2).

Monitor for AV Block: Closely monitor electrophysiological markers, particularly junctional beats, in elderly patients post-ablation to predict potential AV block (Evidence: Moderate 3).

Evaluate Residual Echoes Post-Cryoablation: In cryoablation, residual jumps and echoes may correlate with long-term outcomes, warranting further observation (Evidence: Weak 4).

Abbreviated Procedures Can Be Effective: Shorter ablation procedures can achieve favorable outcomes without extended waiting periods (Evidence: Moderate 6).

References

1 Świętoniowska-Mścisz A, Stec P, Stec S, Szydłowski L, Zagrodzka M, Kusa J et al.. Efficacy and safety of zero-fluoroscopy approach for ablation of atrioventricular nodal reentry tachycardia: experience from more than 1000 cases. Journal of interventional cardiac electrophysiology : an international journal of arrhythmias and pacing 2023. link 2 Jan M, Yazici M, Kalinšek TP, Žižek D, Kuhelj D, Pernat A et al.. Fluoroless radiofrequency and cryo-ablation of atrioventricular nodal reentry tachycardia in adults and children: a single-center experience. Journal of interventional cardiac electrophysiology : an international journal of arrhythmias and pacing 2021. link 3 Fragakis N, Krexi L, Kyriakou P, Sotiriadou M, Lazaridis C, Karamanolis A et al.. Electrophysiological markers predicting impeding AV-block during ablation of atrioventricular nodal reentry tachycardia. Pacing and clinical electrophysiology : PACE 2018. link 4 De Sisti A, Tonet J, Amara W, Raguin D, Aouate P, Gueffaf F et al.. Correlations between long-term results after cryoablation for atrioventricular nodal reentry tachycardia and a residual jump associated or not with a single echo. 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 2012. link 5 Linton NW, Davies DW, Mason A, Lefroy D. Fast pathway ablation using cryotherapy for a patient with a long PR interval in sinus rhythm and AVNRT. Pacing and clinical electrophysiology : PACE 2012. link 6 Steven D, Rostock T, Hoffmann BA, Servatius H, Drewitz I, Müllerleile K et al.. Favorable outcome using an abbreviated procedure for catheter ablation of AVNRT: results from a prospective randomized trial. Journal of cardiovascular electrophysiology 2009. link 7 Sorbera C, Cohen M, Woolf P, Kalapatapu SR. Atrioventricular nodal reentry tachycardia: slow pathway ablation using the transseptal approach. Pacing and clinical electrophysiology : PACE 2000. link 8 Trouton TG, O'Nunain SS, Kim YH, Sosa-Suarez GE, Garan H, Ruskin JN. Curative transcatheter radiofrequency current ablation for atrioventricular nodal reentry tachycardia. Archives of internal medicine 1994. link 9 Fujimura O, Lawton MA, Schoen WJ. Radiofrequency ablation for the fast pathway of atrioventricular node reentry. Evidence for partial damage to the fast and lower common pathways. Chest 1994. link 10 Yeh SJ, Wang CC, Wen MS, Lin FC, Chen IC, Wu D. Radiofrequency ablation therapy in atypical or multiple atrioventricular node reentry tachycardias. American heart journal 1994. link90273-9) 11 Trohman RG, Pinski SL, Sterba R, Schutzman JJ, Kleman JM, Kidwell GA. Evolving concepts in radiofrequency catheter ablation of atrioventricular nodal reentry tachycardia. American heart journal 1994. link90635-1) 12 Willems S, Shenasa M, Borggrefe M, Hindricks G, Chen X, Rotman B et al.. Atrioventricular nodal reentry tachycardia: electrophysiologic comparisons in patients with and without 2:1 infra-His block. Clinical cardiology 1993. link 13 Mann DE, Reiter MJ. Effects of upright posture on atrioventricular nodal reentry and dual atrioventricular nodal pathways. The American journal of cardiology 1988. link90968-x) 14 Arribas F, Cosio FG, Barroso JL. Junctional echoes with slow retrograde conduction without His bundle depolarization: further evidence of reentry within the atrioventricular node. International journal of cardiology 1987. link90252-x)

Nonparoxysmal AV nodal tachycardia