Associazione Nazionale Medici Cardiologi Ospedalieri



High-density mapping of Koch’s triangle during sinus rhythm and typical AV nodal reentrant tachycardia integrated with the direct recording of atrioventricular node structures potential: a multicenter non-randomized study

Matteucci Andrea Roma (Roma) – Sfn | Russo Maurizio Roma (Roma) – Sfn | Galeazzi Marco Roma (Roma) – Sfn | Botto Giovanni Luca Milano (Milano) – Asst Rhodense, Rho-Garbagnate | Castro Antonio Roma (Roma) – Ospedale Sandro Pertini | Zingarini Gianluca Perugia (Perugia) – Ospedale Santa Maria Della Misericordia | Del Giorno Giuseppe Eboli (Eboli) – Presidio Ospedaliero Maria Ss. Addolorata | Papa Andrea Antonio Napoli (Napoli) – Monaldi Hospital | Di Belardino Natale Anzio (Roma) – Ospedale Civile Anzio E Nettuno | Segreti Luca Pisa (Pisa) – Azienda Ospedaliero-Universitaria Pisana | Pepi Patrizia Mantova (Mantova) – Ospedale Carlo Poma | Casale Maria Carla Milano (Milano) – Asst Rhodense | Treglia Simona Milano (Milano) – Boston Scientific | Nicolis Daniele Mantova (Mantova) – Ospedale Carlo Poma | Carbone Angelo Eboli (Eboli) – Presidio Ospedaliero Maria Ss. Addolorata | Lavalle Carlo Roma (Roma) – Umberto I | Malacrida Maurizio Milano (Milano) – Boston Scientific | Pandozi Claudio Roma (Roma) – Sfn | Colivicchi Furio Roma (Roma) – Sfn

Background: Atrioventricular nodal re-entrant tachycardia (AVNRT) is humans' most frequent regular tachycardia. Nevertheless, understanding the exact mechanism and pathways involved in the circuit that sustains the arrhythmia is still incomplete. Also, the recording of nodal potential was performed previously in animals with relative success, but not in humans. The aim of our study is to identify the potential of the compact atrioventricular node (AVN) and inferior extensions by using an electroanatomic mapping of the right atrium and the Koch's triangle in sinus rhythm and during AVNRT

Methods: From March 2021 to July 2022, 79 patients with AVNRT underwent high-resolution mapping and complete ablation in 12 Italian Hospitals. No patients with atrial fibrillation or sustained ventricular tachycardia were included. The diagnosis of AVNRT was established according to standard criteria and diagnostic pacing manoeuvres. The presence and location of SP potentials, i.e., Jackman potential (JP) and Haïssaguerre potential (HP) were evaluated in each patient. The electroanatomic mapping obtained were merged with cardiac computerized tomography (CT) scan

Results: Forty-five cases of successful AVNRT ablation were included in the analysis. The AVN potential has been demonstrated to be a very low frequency signal distinct from atrial, His bundle or ventricular activations, that can be recorded from electrodes overlying the region of the compact AVN by using a non-conventional bipolar electrogram filtering both during sinus rhythm and slow fast AVNRT. AVN potential was identified in all cases in the mid-septal region (#5) in both sinus rhythm and tachycardia. The mid-septal region and the postero-septal regions (#7) bounded anteriorly by the tricuspid annulus and posteriorly by the lateral wall toward the crista terminalis showed a higher prevalence of HP than other regions (46.7% in region #5 and 51.1% in region #7, p<0.0001 vs other regions, respectively). JPs seemed to have a converse distribution across the KT and they were mainly observed in the mid-postero-septal region (73.3%). After 359±121 days of follow-up, no patients had a recurrence of AVNRT

Conclusion: The exact anatomical site and pathways involved in AVNRT are still unclear as well as the analysis and characterisation of the AVN potential. Our results represent the first evidence of the recording of AVN potential. Further studies and technological improvements are needed to confirm our results