Radiofrequency ablation of slow pathway in patients with atrioventricular nodal reentrant tachycardia. Do arrhythmia recurrences correlate with persistent slow pathway conduction or site of successful ablation? (original) (raw)

Methods and techniques Atrioventricular nodal reentrant tachycardia ablation with radiofrequency energy during ongoing tachycardia: is it feasible?

Advances in Interventional Cardiology, 2014

Introduction: Radiofrequency (RF) ablation of the slow pathway for treatment of atrioventricular nodal reentrant tachycardia (AVNRT) is conventionally performed during sinus rhythm. Aim: To evaluate the clinical and electrophysiological features and the short-and long-term results of slow pathway RF ablation during ongoing AVNRT. Material and methods: A total of 282 consecutive patients with AVNRT undergoing RF catheter ablation were analysed. Patients whose tachycardia episodes could not be controlled during RF energy application and who underwent slow pathway ablation or modification during ongoing tachycardia formed the study group (group 1, n = 16) and those ablated during sinus rhythm formed the control group (group 2, n = 266). Results: Of the clinical characteristics, only the frequency of tachycardia attacks was higher in group 1 (3.3 ±1.2 vs. 2.1 ±0.9 attacks/month, p < 0.001). Among the baseline electrophysiological measurements, the echo zone lasted significantly longer in group 1 than in group 2 (78 ±25 ms vs. 47 ±18 ms; p < 0.001). The immediate procedural success rate was 100% in both groups. There were no significant differences between groups regarding the mean number of radiofrequency energy applications (5.2 ±4.2 vs. 5.8 ±3.9), total procedure times (42.4 ±30.5 min vs. 40.2 ±29.4 min) and fluoroscopy times (11.4 ±8.5 min vs. 12.2 ±9.3 min) (p > 0.050 for all). All patients were followed-up for 29 ±7 months; only 2 patients (< 1%) in group 2 recurred (p > 0.050). No permanent atrioventricular block was observed. Conclusions: The RF catheter ablation or modification of the slow pathway during ongoing AVNRT is feasible with acceptable short-and long-term efficacy and safety. However, this approach needs to be clarified with large-scale studies.

Atrioventricular node reentrant tachycardia in patients with a long fast pathway effective refractory period: Clinical features, electrophysiologic characteristics, and results of radiofrequency ablation

American Heart Journal, 1997

Twenty-two patients (group 1 ) with AV node reentrant tachycardia and a baseline fast pathway effective refractory period (ERP) >500 msec were compared with 30 consecutive patients (group 2) with AV node reentrant tachycardia and a fast pathway ERP <500 msec. Both groups underwent slow pathway ablation. In the patients with complete elimination of slow pathway, the fast pathway ERP and shortest 1 : 1 conduction cycle length shortened significantly after ablation but was greater in group 1 (n = 14) than in group 2 (n = 21) (125 + 78 msec vs 48 + 29 msec, p < 0.001 and 103 + 72 msec vs 52 _+ 30 msec, p < 0.001, respectively). In group 1, the shortening of fast pathway ERP was correlated to baseline difference between anterograde fast and anterograde slow ERP (r = 0.806, p < 0.001, slope = 1.08), and the shortening of fast pathway shortest 1:1 conduction cycle length was correlated to baseline difference between anterograde fast and anterograde slow shortest 1:1 conduction cycle length (r = 0.885, p < 0.001, slope = 1.47). During follow-up bradycardia did not develop in any patient and no one required pacing. This shortening of the fast pathway ERP and shortest 1:1 conduction cycle length after complete elimination of slow pathway reduced the concern of subsequent impairment of AV node conduction. (Am HeartJ 1997;134:387-94.) The mechanism of atrioventricular (AV) node reentry is based on a substrate with two functionally or anatomically distinct AV node pathways that permit reciprocation. The fast pathway has a shorter conduction time and a longer effective refractory period (ERP), whereas the slow pathway has a longer conduction time and a shorter ERP. 1-3 Radiofrequency catheter ablation techniques could provide a permanent cure and offer an option for control of symptoms in these patients. 4-6

Arrhythmia recurrences are rare when the site of radiofrequency ablation of the slow pathway is medial or anterior to the coronary sinus os

Europace, 2002

The site of successful ablation of the slow atrioventricular (AV) nodal pathway may be located in the posteroseptal or midseptal area. We have previously shown that the site of successful radiofrequency (RF) ablation of the slow pathway, rather than residual slow pathway conduction correlates with AV nodal re-entrant tachycardia (AVNRT) recurrences, with more recurrences noted in inferoposterior (to the coronary sinus os) locations. Accordingly, we have since modified our approach, and in a consecutive series of 105 patients we have performed slow pathway RF ablation exclusively at medial or anterior locations, with the objective of prospectively examining the recurrence rate of AVNRT incurred with this approach. The study included 40 men and 65 women, aged 42 +/- 18 years, having RF ablation for symptomatic AVNRT exclusively in anterior to the coronary sinus os locations. A combined anatomical and electrophysiological approach to slow pathway ablation was employed. This series of patients was compared with the previous series of 55 patients (historical group) with AVNRT undergoing RF ablation at both inferoposterior and anteromedial locations. The mean cycle length of the induced AVNRT was 329 +/- 48 ms. RF ablation was successful in all patients (100%). A mean of 7 +/- 6 lesions were applied. Persistent jump or echo beats were noted in 48 patients (46%). The procedure lasted for 2.1 +/- 1.0 h. Fluoroscopy time was 23 +/- 14 min. Procedures were complicated by heart block in two patients (1.9%). Over 26 +/- 19 months, there has been only one recurrence of AVNRT (1%). The historical group had similar age (37 +/- 18 years), gender (17 men/38 women), AVNRT cycle length (340 +/- 60 ms), number of RF lesions (9 +/- 6), or residual slow pathway conduction (42%), but longer fluoroscopy time (41 +/- 25 min) and procedure duration (4 +/- 1 h), and a significantly higher recurrence rate (seven patients/13%) (P=0.004) at a much shorter follow-up period of 12 +/- 8 months. AVNRT recurrences are rare (1%) when slow pathway RF ablation is performed in medial or anterior locations at the tricuspid annulus, rather than in inferoposterior sites, whereby a higher (13%) recurrence rate has been previously noted.

Assessment of the influence of radiofrequency catheter ablation of the slow pathway of the atrioventricular node on cardiac function in patients with atrioventricular nodal reentrant tachycardia: a speckle tracking echocardiography study

Türk Kardiyoloji Derneği arşivi : Türk Kardiyoloji Derneğinin yayın organıdır, 2014

Typical atrioventricular nodal reentrant tachycardia (AVNRT) can be cured with slow pathway ablation. This study was designed to assess the alterations in atrial and ventricular functioning using speckle tracking echocardiography in consecutive patients with typical AVNRT who underwent slow pathway radiofrequency (RF) ablation. Included in this study were 23 consecutive patients with symptomatic drug-resistant typical (slow-fast) AVNRT, all of whom underwent an invasive electrophysiology study and RF ablation. Patients underwent transthoracic echocardiographic evaluation 24 hours before and 24 hours after the ablation procedure. AVNRT was induced during the electrophysiological study, and RF ablation successfully eliminated tachyarrhythmia in 23 (100%) patients. The atrial-His (A-H) interval was decreased in the post-ablation period compared to the pre-ablation period without the occurrence of immediate conduction disturbances. Peak left atrial longitudinal strain during the reservo...

Analysis of junctional ectopy during radiofrequency ablation of the slow pathway in patients with atrioventricular nodal reentrant tachycardia

Circulation, 1994

BACKGROUND Junctional ectopy may occur during radiofrequency (RF) catheter ablation of the slow pathway in patients with atrioventricular nodal reentrant tachycardia (AVNRT). The purpose of the present study was to characterize this junctional ectopy quantitatively. METHODS AND RESULTS The subjects of this study were 52 consecutive patients with AVNRT who underwent slow pathway ablation and 5 additional patients included retrospectively because they had developed high-degree atrioventricular (AV) block during the procedure. A combined anatomic and electrogram mapping approach was used for slow pathway ablation, and AVNRT was successfully eliminated in all patients. In the group of 52 consecutive patients, the incidence of junctional ectopy was significantly higher during 52 effective applications of RF energy than during 366 ineffective applications (100% versus 65%, P < .001). Compared with ineffective RF energy applications, successful RF energy applications had a significantly...

Intracardiac echocardiography guided radiofrequency catheter ablation of the slow pathway in atrioventricular nodal reentrant tachycardia

Journal of interventional cardiac electrophysiology : an international journal of arrhythmias and pacing, 2002

ICE has demonstrated its utility in imaging right atrial structures but its utility in slow pathway (SP) ablation has not been documented in a randomized trial. The feasibility of using ICE as a imaging modality to identify the effective site of SP ablation was done in part one of the study comprising 10 patients of typical AVNRT. Subsequently, a prospective randomized study was done comparing the conventional (group A) and ICE guided (group B) ablation of the SP. Each group had 20 patients of typical AVNRT. Ablation in the conventional arm was guided by intracardiac electrograms and fluoroscopy. Group B patients underwent SP ablation guided primarily by ICE imaging; fluoroscopy was used mainly for initial placement of catheters. Reliable & stable ICE images were obtained in all patients. Part I of the study showed that RF pulses given when the ablation catheter was seen to cross the atrioventricular muscular septum (AVMS), always resulted in junctional rhythm. In Group B, RF pulse ...