Spatial Extension of His Bundle in the Triangle of Koch in Atrioventricular Nodal Reentrant Tachycardia

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.

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Cross sectional analytic study of the relationship between age and the distance from His bundle to slow pathway in atrioventricular nodal reentrant tachycardia (AVNRT) patients using 3D mapping

European Heart Journal ◽

10.1093/ehjci/ehaa946.0688 ◽

2020 ◽

Vol 41 (Supplement_2) ◽

Author(s):

C Srisakvarakul ◽

W Boonyapisit ◽

C Sriprom

Keyword(s):

Negative Correlation ◽

Pearson Correlation ◽

Age Groups ◽

Slow Pathway ◽

Atrioventricular Nodal Reentrant Tachycardia ◽

Reentrant Tachycardia ◽

Cross Sectional ◽

His Bundle ◽

The Mean ◽

The Relationship

Abstract Background and objective The incidence of atrioventricular nodal reentrant tachycardia (AVNRT) in elderly patients has increased due to an increased in life expectancy of the general population. Slow pathway (SPs) ablation is considered the treatment of choice for patients with AVNRT. This study is interested in the relationship of the distance from SPs to His bundle electrogram (HBEs) in various age groups because understanding of anatomy clearly could guide treatment patients by using radiofrequency ablation to be easier and safer. Design and methods A cross-sectional study was analyzed in patients diagnosed with AVNRT and underwent SPs ablation using EnSite NavX mapping system guided therapy. The distance from SPs to the lowest HBEs recorded was measured. Relationship between distance from SPs to HBEs and age was analyzed by Pearson correlation. Results A total 68 adults diagnosed with AVNRT (27.9% males, mean age 52.43 years old) were included. The mean distance from SPs to HBEs is shorter in the group older than or equal to 60 years old (n=24, mean age 70.70 years old) compared to the group younger than 60 years old (n=44, mean age 42.45 years old) (13.77 vs. 17.73 millimeter, p=0.024). Average fluoroscopy time was greater in the older group compared to the younger group (24.43 vs. 16.52 minutes, p=0.002) while the procedure time in both groups was not different (105.1 vs. 85.48 minutes, p=0.09). The distance from SPs to HBEs was negative correlation with age with the coefficient of −0.392 (p<0.001). When dividing the age group into three age groups, the group that younger than 40 years old (n=15, mean age 29.73 years old), 40 to 60 years old (n=29, mean age 49.03) and older than 60 years old (n=24, mean 70.70 age), the average distance from SPs to HBEs was 20.77, 16.15 and 13.77 millimeter respectively. The mean distance from SPs to HBEs in the group younger than 40 years old is significant statistically different to the group that is older than 60 years old (p=0.006). Slow pathway ablation was successful in all patients in this study except for one patient who was 72 years old because frequent transient atrioventricular block occurred during ablation. Conclusion Distance from SPs to HBEs was negative correlation with age by measuring with 3-dimentional mapping. Distance from SPs to HBEs in each groups Funding Acknowledgement Type of funding source: None

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Nonfluoroscopic Imaging as Guidance for Radiofrequency Ablation of Atrioventricular Nodal Reentrant Tachycardia after Mustard Repair

Texas Heart Institute Journal ◽

10.14503/thij-15-5548 ◽

2017 ◽

Vol 44 (1) ◽

pp. 58-61

Author(s):

Jan Hluchy ◽

Dinh Q. Nguyen ◽

Henrik Sobczak ◽

Bodo Brandts

Keyword(s):

Radiofrequency Ablation ◽

Superior Vena ◽

Three Dimensional ◽

Vena Cava ◽

Atrioventricular Nodal Reentrant Tachycardia ◽

Reentrant Tachycardia ◽

3 Dimensional ◽

His Bundle ◽

Congenital Cardiac Malformation ◽

Transaortic Approach

Most tachycardias in the pulmonary venous atrium are inaccessible by direct means and require either a retrograde approach or a transseptal approach for ablation. We present a case in which successful radiofrequency ablation of common atrioventricular nodal reentrant tachycardia was accomplished via a retrograde transaortic approach guided by nonfluoroscopic mapping with use of the NavX™ mapping system. The patient was a 49-year-old woman who at the age of 4 years had undergone Mustard repair for complete dextrotransposition of the great arteries. Three-dimensional reconstructions of the ascending aorta, right ventricle, systemic venous atrium, left ventricle, and superior vena cava–inferior vena cava baffle complex were created, and the left-sided His bundle was marked. After a failed attempt at ablation from the systemic venous side, we eliminated the atrioventricular nodal reentrant tachycardia by ablation from the pulmonary venous side. This case is, to our knowledge, the first report of successful radiofrequency ablation of common atrioventricular nodal reentrant tachycardia after Mustard repair for this congenital cardiac malformation in which ablation was guided by 3-dimensional nonfluoroscopic imaging. This imaging technique enabled accurate anatomic location of the ablation catheters in relation to the His bundle marked from the systemic venous side.

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