Abstract 2647: Analysis of the Anatomical and Electrophysiological Characteristics of Tachycardia Circuit in Atrioventricular Nodal Reentrant Tachycardia Accompanied by the Block in the Upper Common Pathway

Circulation ◽  
2007 ◽  
Vol 116 (suppl_16) ◽  
Author(s):  
Kenji Morihisa ◽  
Hiroshige Yamabe ◽  
Yasuaki Tanaka ◽  
Takashi Uemura ◽  
Hisao Ogawa

We examined the anatomical and electrophysiological characteristic of the atrioventricular nodal reentrant tachycardia (AVNRT) accompanied by the ventriculo-atrial block during tachycardia, suggesting the presence of upper common pathway in 8 patients. Tachycardia was induced by the atrial burst and/or extrastimulation followed by the AH jump and the earliest atrial electrogram was observed at the His bundle (HB) site in all patients. The HA block was observed after gradual prolongation of the HA interval in 2 patient and abruptly in 6 patients. After administration of isoproterenol, 1:1 HA conduction was resumed in all patients. The tachycardia cycle length, AeHe interval and HeAe interval were 357±89, 275±55 and 80±44 msec, respectively. Single extrastimulus delivered from the HB site reset the tachycardia as soon as it was delivered during late diastole. However, single extrastimulus delivered from the inferior portion of the coronary sinus ostium (I-CSOS) was unable to reset the tachycardia without capturing the earliest atrial electrogram at the HB site, suggesting that atrium is not involved in the circuit. Thus, the longest coupling interval of single extrastimulus that reset the tachycardia at the HB site was significantly longer than that at I-CSOS (347±89 msec vs. 324±109 msec, p=0.012). The following return cycle after extrastimulation at the HB site did not differ from the tachycardia cycle length (357±89 msec, vs. 357±89 msec, p=NS), however, that at I-CSOS was significantly longer than the tachycardia cycle length (398±85 msec, vs. 357±89 msec, p=0.012). Catheter ablation was performed in a stepwise fashion starting at the inferior CSOS. Although the results of single extrastimulation showed that the atrial myocardium at I-CSOS was out of the reentry circuit, ablation near the I-CSOS, distant from HB site, selectively eliminated slow pathway conduction in all patients without impairment of fast pathway conduction. Conclusions: The AVNRT with upper common pathway has the characteristic of relatively long HA interval during tachycardia. Sub-atrial tissue, but not the atrium, extending from the HB site to I-CSOS forms the upper common pathway in AVNRT. It was shown that upper common pathway has an anatomical structure of a certain range.

2016 ◽  
Vol 5 (2) ◽  
pp. 130 ◽  
Author(s):  
Demosthenes G Katritsis ◽  
Mark E Josephson ◽  
◽  

Atrioventricular nodal reentrant tachycardia (AVNRT) should be classified as typical or atypical. The term ‘fast-slow AVNRT’ is rather misleading. Retrograde atrial activation during tachycardia should not be relied upon as a diagnostic criterion. Both typical and atypical atrioventricular nodal reentrant tachycardia are compatible with varying retrograde atrial activation patterns. Attempts at establishing the presence of a ‘lower common pathway’ are probably of no practical significance. When the diagnosis of AVNRT is established, ablation should be only directed towards the anatomic position of the slow pathway. If right septal attempts are unsuccessful, the left septal side should be tried. Ablation targeting earliest atrial activation sites during typical atrioventricular nodal reentrant tachycardia or the fast pathway in general for any kind of typical or atypical atrioventricular nodal reentrant tachycardia, are not justified. In this review we discuss current concepts about the tachycardia circuit, electrophysiologic diagnosis, and ablation of this arrhythmia.


2020 ◽  
Vol 13 (11) ◽  
Author(s):  
Yoshiaki Kaneko ◽  
Tadashi Nakajima ◽  
Shuntaro Tamura ◽  
Hiroshi Hasegawa ◽  
Takashi Kobari ◽  
...  

Background: Superior-type fast-slow (sup-F/S-) atrioventricular nodal reentrant tachycardia (AVNRT) is a rare AVNRT variant using a superior slow pathway (SP) as the retrograde limb. Its intracardiac appearance, characterized by a short atrio-His (AH) interval and the earliest site of atrial activation in the His-bundle, is an initial indicator for making a diagnosis. Methods: Among 22 consecutive patients with sup-F/S-AVNRT, 3 (age, 68–81 years) patients had an apparent slow-fast (S/F-) AVNRT characterized by a long AH interval and the earliest site of atrial activation in or superior to the His-bundle region (tachy-long-AH). Results: The diagnosis of sup-F/S-AVNRT was based on the standard criteria in 2 patients and on the occurrence of Wenckebach-type atrioventricular block during tachycardia, which was attributable to a block at the lower common pathway (LCP) below the circuit of the AVNRT, detected owing to the lower common pathway potentials, in one patient. As with the typical S/F-AVNRT, tachy-long-AH was induced after a jump in the AH interval. In contrast to typical S/F-AVNRT, fluctuation in the ventriculoatrial interval was observed during the tachy-long-AH. Ventricular overdrive pacing was unable to entrain or terminate the tachy-long-AH. Moreover, the tachy-long-AH reciprocally transited to/from sup-F/S-AVNRT spontaneously or was triggered by ventricular contractions while the atrial cycle length and earliest site of atrial activation remained unchanged. Both tachycardias were cured by ablation at a single site in the right-side para-Hisian region of 2 patients and the noncoronary aortic cusp of one patient. Collectively, the essential circuit of both tachycardias was identical, and the tachy-long-AH was diagnosed as another phenotype of sup-F/S-AVNRT accompanied by sustained antegrade conduction via another bystander slow pathway breaking through the His-bundle owing to the repetitive antegrade block at the lower common pathway, thus representing a long AH interval during the ongoing sup-F/S-AVNRT. Conclusions: An unknown sup-F/S-AVNRT phenotype exists that apparently mimics the typical S/F-AVNRT and is also an unknown subtype of apparent S/F-AVNRT.


Medicina ◽  
2009 ◽  
Vol 45 (8) ◽  
pp. 632 ◽  
Author(s):  
Rima Šileikienė ◽  
Dalia Bakšienė ◽  
Vytautas Šileikis ◽  
Tomas Kazakavičius ◽  
Jolanta Vaškelytė ◽  
...  

Radiofrequency ablation of the slow pathway is an effective method of treatment in children with atrioventricular nodal reentrant tachycardia. The aim of our study was to evaluate anterograde conduction properties in children before and after radiofrequency ablation of the slow pathway and to determine the efficacy and safety of this method. Material and methods. Noninvasive transesophageal electrophysiological examination was performed in 30 patients at the follow-up period (mean duration, 3.24 years) after radiofrequency ablation of the slow pathway. Results. The slow pathway function was observed in 13 patients one day after ablation, in 26 patients during the follow-up period, and in 28 patients after administration of atropine sulfate. Atrioventricular node conduction was significantly decreased the following day after ablation and at the follow-up versus the preablation (165.2 [30.2] bmp and 146.3 [28.5] bpm versus 190.9 [31.4] bpm; P<0.001). The atrioventricular node effective refractory period prolonged significantly the following day after ablation and at the follow-up versus the preablation (319.3 [55.3] ms and 351.0 [82.1] ms versus 248.3 [36.6] ms; P<0.001). Effective refractory period of the fast pathway prolonged significantly as compared with the preablation (from 408.0 [60.4] ms to 481.2 [132.9] ms; P=0.005). The prolongation of effective refractory period of the slow pathway was more significant than effective refractory period of the fast pathway at the follow-up (P<0.001). Two late recurrences occurred; one patient had atrial tachycardia. Conclusion. Children with atrioventricular nodal reentrant tachycardia can be effectively and safety cured by ablative therapy. The end-point during slow pathway ablation should be the abolition of tachycardia with preservation of dual atrioventricular nodal physiology.


2022 ◽  
Vol 11 (1) ◽  
pp. 282
Author(s):  
Nicolas Clementy ◽  
Gérôme Pineaud ◽  
Arnaud Bisson ◽  
Dominique Babuty

Catheter ablation of the slow pathway in patients with atrioventricular nodal reentrant tachycardia (AVNRT) is mainly performed using anatomical landmarks. We sought to see whether a new ablation catheter equipped with mini-electrodes may facilitate the mapping of slow pathway potentials for AVNRT ablation. We prospectively included patients referred for AVNRT in our center. Mapping and ablation were performed using an irrigated catheter equipped with 3 insulated mini-electrodes on the distal tip. Thirteen consecutive patients were included (85% female, median age 46 years). Slow pathway potentials could be identified in 77% of cases on mini-electrode bipolar tracings, versus 15% on conventional bipolar tracings (p = 0.0009). At the end of the procedure, double potentials on the ablation line were identified in all patients, only on mini-electrode bipolar tracings. Following ablation, an interval separating double potentials in sinus rhythm ≥15% of baseline tachycardia cycle length was associated with non-inducibility in all patients (p < 0.0001). No recurrence occurred during 1 year of follow-up. The use of mini-electrodes may help target slow pathway potentials during AVNRT ablation. Identification of sufficiently split double potentials on the ablation line might represent an electrophysiological endpoint in these patients.


2005 ◽  
Vol 46 (5) ◽  
pp. 899-902 ◽  
Author(s):  
Yuji Okuyama ◽  
Takafumi Oka ◽  
Hiroya Mizuno ◽  
Taku Sakai ◽  
Atsushi Hirayama ◽  
...  

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