Quantitative Analysis and Characteristics of the Electrograms Recorded Within the Non-Coronary Aortic Sinus of Valsalva

Abstract

Circ J 2009; 73: 838 -845 ecent studies have demonstrated that some supraventricular tachycardias that have their origins near the atrioventricular node (AVN) or His-bundle region can be eliminated by radiofrequency (RF) catheter ablation from the non-coronary sinus of Valsalva (NSV). [1][2][3][4][5][6] We have also reported 2 cases of supraventricular tachycardias, which consisted of an atrial tachycardia (AT) 1 and atrioventricular (AV) orthodromic tachycardia (AVRT). 2 However, the characteristics of the electrograms recorded from the NSV during normal sinus rhythm as well as during the tachycardia have not been sufficiently examined. Furthermore, the difference between the electrograms recorded from the NSV and those recorded from the other 2 aortic sinuses of Valsalva has not been clarified.Even if an early atrial activation during the tachycardia is found on the right atrial (RA) anteroseptum, sufficient deliveries of the RF energy at that site might be impossible because of the high risk for the impairment of the AV conduction. [1][2][3][4][5][6] In such a situation, RF ablation at the NSV might eliminate the tachycardia with no complications. [1][2][3][4][5][6] However, because of the vicinity to the AVN and His-bundle region, the RF catheter ablation at the NSV always carries the risk of impairing the conduction of the AVN. In fact, the first case report of RF ablation from the NSV was a case in which a complete AV block was created by the RF ablation from the NSV. 7 However, the detailed information on the distance from the NSV to the AVN or His-bundle region or the prevalence of recording a His-bundle potential at the NSV, both of which seem to be very important to estimate the risk of AVN conduction block during the RF energy application from the NSV, 8,9 was lacking. Accordingly, in the present study, we performed a quantitative measurement of the electrograms recorded from the aortic sinus of Valsalva during sinus rhythm and/or the tachycardia to clarify those points. Methods Study Population and ProtocolThis study consisted of 3 protocols as follows. Protocol I: Recording of the NSV Electrograms in Patients With Supraventricular TachycardiaThe mapping and recording of the NSV electrograms were performed during sinus rhythm as well as during the tachycardia in 5 patients with paroxysmal supraventricular tachycardia (3 women; mean age, 64±12 years) in whom successful elimination of the tachycardia could be achieved by an RF energy (Received September 16, 2008; revised manuscript received December 5, 2008; accepted January 4, 2009; released online March 31, 2009 Background: Some supraventricular tachycardias could be ablated from the non-coronary sinus of Valsalva (NSV). However, the characteristics of the NSV electrograms have not been clarified. Methods and Results:A quantitative analysis of the NSV electrograms was performed in 5 patients with tachycardias arising from near the atrioventricular node (AVN) and the His-bundle region, and in 20 control subjects. In another 7 control subjects, th...

Discrimination of atypical atrioventricular nodal reentrant tachycardia from atrial tachycardia by the V‐A‐A‐V response

“…In most of these studies, this AT was diagnosed in accordance with the original report 10 . The main criteria, used in multiple previous observations, include a V‐A‐A‐V response upon ventricular induction or entrainment, 35–39,43,44,46–48,50,51 AV block during the ongoing tachycardia, 32,33,35,38–40,42–44,47,48,51 VA dissociation during ventricular overdrive stimulation of the tachycardia, 35,38,40,42,43,47,49–51 a variability of the atrial cycles preceding the ventricular cycles during tachycardia, 33,35,38,40,42,43,47,50,51 absence of VA linking during differential atrial entrainment stimulation 35,44,46,48,51 and a non‐reproducible atrial activation sequence with ventricular stimulation during tachycardia 32,33,35,37,38,43,50,51 . However, it has now been shown that these criteria can all be satisfied in patients presenting with sup‐F/S‐AVNRT 3–5,17,52 .…”

Catheter Ablation of Tachyarrhythmias From the Aortic Sinuses of Valsalva

“…53 The aforementioned anatomic features of the 3 aortic sinuses are responsible for the differences in the electrogram recordings within these aortic sinuses: 37,43 the NSV electrograms during sinus rhythm have a larger atrial amplitude than ventricular amplitude, and the ratio of the atrial amplitude to the ventricular amplitude is usually >1, which is apparently different from the LSV and RSV electrograms (Figure 7). 37 Analysis of the electrogram is helpful for identifying the correct positioning of the mapping/ablation catheter at the aortic sinuses of Valsalva during the ablation procedure. Fortunately, most reported cases of catheter ablation of NSV tachycardias originating from near the AV node or Hisbundle region have not resulted in impairment of AV conduction.…”

“…However, during tachycardia, it is difficult to confirm whether or not there is a Hisbundle potential, probably because of greater baseline drift and artifact during the tachycardia than during sinus rhythm or a wider distance between the His-bundle region and the ablation catheter during the tachycardia than during sinus rhythm (Figure 8). 37 Therefore, the presence of a His-bundle potential during sinus rhythm should be assessed before ablation at the NSV. To avoid impairment of AV conduction during RF energy delivery, it is useful to be aware of any prolongation of the PQ, A-H, or H-V interval.…”

“…The RSV is also adjacent to His bundle region, and the His bundle potential is recorded more often at the RSV than the NSV during sinus rhythm. 37 Therefore, RF ablation in the RSV should be performed in the same manner as in the NSV.…”

Radiofrequency Catheter Ablation of Ventricular Tachyarrhythmia Under Navigation Using EnSite Array

“…7-9,11, 12 The origins of focal VTs/PVCs were distributed at RVOT, the lateral RV, His bundle region, tricuspid annulus, aortic sinus cusp, and LV endocardium, and those of macroreentrant VTs were distributed at RVOT, lateral RV, and LV endocardium. [13][14][15] In focal VTs/PVCs, activation occurred from the VT/PVC focus, where VUE exhibited a QS or qRS pattern depending on the case, and from which activation spread out toward the entire ventricle. RFA targeting the VT/PVC focus resulted in elimination of almost all VTs/PVCs, even if VT/PVC focus was multiple and changed in location after each RF application.…”