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David L Ross - One of the best experts on this subject based on the ideXlab platform.
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high resolution mapping of koch s triangle using sixty electrodes in humans with atrioventricular junctional av nodal Reentrant tachycardia
Circulation, 1993Co-Authors: Mark A Mcguire, David C Johnson, John B Uther, John P Bourke, Monica Robotin, W Meldrumhanna, Graham R Nunn, David L RossAbstract:BACKGROUNDRecent evidence suggests that atrioventricular junctional Reentrant tachycardia (AVJRT) uses a Reentrant circuit that involves the atrioventricular (AV) node, the atrionodal connections, and perinodal atrial tissue. Electrogram morphology has been used to target the delivery of radiofrequency energy to the site of the "slow pathway," a component of this Reentrant circuit. The aim of this study was to localize precisely the sites of atrionodal connections involved in AVJRT and to examine atrial electrogram morphologies and their spatial distribution over Koch's triangle.METHODS AND RESULTSElectrical activation of Koch's triangle and the proximal coronary sinus was examined in 13 patients using a 60-point plaque electrode and computerized mapping system. Recordings were made during sinus rhythm (n = 12), left atrial pacing (n = 8), ventricular pacing (n = 12), and AVJRT (n = 12). During sinus rhythm electrical activation approached Koch's triangle and the AV node from the direction of the anterior...
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patients with two types of atrioventricular junctional av nodal Reentrant tachycardia evidence that a common pathway of nodal tissue is not present above the Reentrant circuit
Circulation, 1991Co-Authors: Mark A Mcguire, Kaichiu Lau, David C Johnson, David Richards, John B Uther, David L RossAbstract:BACKGROUNDThe site of the Reentrant circuit in atrioventricular (AV) junctional Reentrant tachycardia has not been defined; in particular, the existence of a common pathway of AV nodal tissue above the Reentrant circuit is controversial.METHODS AND RESULTSTwo types of AV junctional Reentrant tachycardia were induced in each of three patients at electrophysiological study. In one type of tachycardia (anterior), the onset of atrial activity occurred from 0 to 12 msec before the onset of ventricular activation, and earliest atrial activity was recorded near the His bundle. In the second type of tachycardia (posterior), the ventriculoatrial intervals were longer (76-168 msec), and earliest atrial activity was recorded near the mouth of the coronary sinus. In individual patients, the two types of tachycardia had different cycle lengths. Posterior AV junctional Reentrant tachycardia was not a fast-slow form of AV junctional reentry in at least two of the three patients. Surgical cure was attempted in two patien...
Jun-jack Cheng - One of the best experts on this subject based on the ideXlab platform.
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Spontaneous transition of 2:1 atrioventricular block to 1:1 atrioventricular conduction during atrioventricular nodal Reentrant tachycardia: evidence supporting the intra-Hisian or infra-Hisian area as the site of block.
Journal of Cardiovascular Electrophysiology, 2003Co-Authors: Chern-en Chiang, Wen-chung Yu, Jun-jack Cheng, Yu-an Ding, Mau-song Chang, Shih-ann ChenAbstract:Introduction: The incidence of spontaneous transition of 2:1 AV block to 1:1 AV conduction during AV nodal Reentrant tachycardia has not been well reported. Among previous studies, controversy also existed about the site of the 2:1 AV block during AV nodal Reentrant tachycardia. Methods and Results: In patients with 2:1 AV block during AV nodal Reentrant tachycardia, the incidence of spontaneous transition of 2:1 AV block to 1:1 AV conduction and change of electrophysiologic properties during spontaneous transition were analyzed. Among the 20 patients with 2:1 AV block during AV nodal Reentrant tachycardia, a His-bundle potential was absent in blocked beats during 2:1 AV block in 8 patients, and the maximal amplitude of the His-bundle potential in the blocked beats was the same as that in the conducted beats in 4 patients and was significantly smaller than that in the conducted beats in 8 patients (0.49 ± 0.25 mV vs 0.16 ± 0.07 mV, P = 0.007). Spontaneous transition of 2:1 AV block to 1:1 AV conduction occurred in 15 (75%) of 20 patients with 2:1 AV block during AV nodal Reentrant tachycardia. Spontaneous transition of 2:1 AV block to 1:1 AV conduction was associated with transient right and/or left bundle branch block. The 1:1 AV conduction with transient bundle branch block was associated with significant His-ventricular (HV) interval prolongation (66 ± 19 ms) compared with 2:1 AV block (44 ± 6 ms, P < 0.01) and 1:1 AV conduction without bundle branch block (43 ± 6 ms, P < 0.01). Conclusion: The 2:1 AV block during AV nodal Reentrant tachycardia is functional; the level of block is demonstrated to be within or below the His bundle in a majority of patients with 2:1 AV block during AV nodal Reentrant tachycardia, and a minority are possibly high in the junction between the AV node and His bundle. (J Cardiovasc Electrophysiol, Vol. 14, pp. 1337-1341, December 2003)
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experimentally created atrioventricular node Reentrant tachycardia in the dog evidence of a brake system for nodal reentry in the anterior interatrial septum
Journal of the American College of Cardiology, 1993Co-Authors: Fangyue Lin, Jun-jack ChengAbstract:Objectives. The purpose of the study was to investigate the hypothesis that nodal approaches of both anterior and posterior atrial input sites of the atrioventricular (AV) node contribute to part of the circuit of AV node Reentrant tachycardia. Thus, tachycardia might be elicited by a premature atrial impulse that arrived at the AV node through one input site while blocked at another. Background. Atrioventricular node Reentrant tachycardia is the most common supraventricular tachycardia in humans, yet the exact pathway of the Reentrant circuit is unknown. Methods. In eight dogs, an operation that blocked atrial impulses from the anterior input site to the AV node was performed through a right thoracotomy with the inflow occlusion method. The right atrial free wall and the anterior atrial septum between the sinoatrial node and the AV node were completely divided, whereas the tissues within the triangle of Koch remained intact. Thus, atrial impulses were blocked from the anterior input site in the right atrium and the atrial septum and were conducted only through the left atrial free wall to the posterior atrial septum into the AV node. Results. In a baseline electrophysiologic study before operation, dual AV conduction pathways were demonstrated in seven of eight dogs, but none of the seven had inducible AV node Reentrant tachycardia. A repeat study 1 week postoperatively revealed that 1) both PR and AH intervals were prolonged during sinus rhythm (p < 0.01); 2) anterograde and retrograde conduction of the AV node showed no significant changes; and 3) AV node Reentrant tachycardia was induced in four dogs (50%), of which three had sustained tachycardia. Conclusions. These results are compatible with the hypothesis that both nodal approaches of atrial input sites of the AV node contribute to part of the circuit of AV node Reentrant tachycardia. They also confirm Moe's hypothesis of the existence of a brake system that prevents sustained AV node reentry. Our data suggest that the brake system is located in the anterior atrial septum.
Mark A Mcguire - One of the best experts on this subject based on the ideXlab platform.
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high resolution mapping of koch s triangle using sixty electrodes in humans with atrioventricular junctional av nodal Reentrant tachycardia
Circulation, 1993Co-Authors: Mark A Mcguire, David C Johnson, John B Uther, John P Bourke, Monica Robotin, W Meldrumhanna, Graham R Nunn, David L RossAbstract:BACKGROUNDRecent evidence suggests that atrioventricular junctional Reentrant tachycardia (AVJRT) uses a Reentrant circuit that involves the atrioventricular (AV) node, the atrionodal connections, and perinodal atrial tissue. Electrogram morphology has been used to target the delivery of radiofrequency energy to the site of the "slow pathway," a component of this Reentrant circuit. The aim of this study was to localize precisely the sites of atrionodal connections involved in AVJRT and to examine atrial electrogram morphologies and their spatial distribution over Koch's triangle.METHODS AND RESULTSElectrical activation of Koch's triangle and the proximal coronary sinus was examined in 13 patients using a 60-point plaque electrode and computerized mapping system. Recordings were made during sinus rhythm (n = 12), left atrial pacing (n = 8), ventricular pacing (n = 12), and AVJRT (n = 12). During sinus rhythm electrical activation approached Koch's triangle and the AV node from the direction of the anterior...
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patients with two types of atrioventricular junctional av nodal Reentrant tachycardia evidence that a common pathway of nodal tissue is not present above the Reentrant circuit
Circulation, 1991Co-Authors: Mark A Mcguire, Kaichiu Lau, David C Johnson, David Richards, John B Uther, David L RossAbstract:BACKGROUNDThe site of the Reentrant circuit in atrioventricular (AV) junctional Reentrant tachycardia has not been defined; in particular, the existence of a common pathway of AV nodal tissue above the Reentrant circuit is controversial.METHODS AND RESULTSTwo types of AV junctional Reentrant tachycardia were induced in each of three patients at electrophysiological study. In one type of tachycardia (anterior), the onset of atrial activity occurred from 0 to 12 msec before the onset of ventricular activation, and earliest atrial activity was recorded near the His bundle. In the second type of tachycardia (posterior), the ventriculoatrial intervals were longer (76-168 msec), and earliest atrial activity was recorded near the mouth of the coronary sinus. In individual patients, the two types of tachycardia had different cycle lengths. Posterior AV junctional Reentrant tachycardia was not a fast-slow form of AV junctional reentry in at least two of the three patients. Surgical cure was attempted in two patien...
Shih-ann Chen - One of the best experts on this subject based on the ideXlab platform.
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Spontaneous transition of 2:1 atrioventricular block to 1:1 atrioventricular conduction during atrioventricular nodal Reentrant tachycardia: evidence supporting the intra-Hisian or infra-Hisian area as the site of block.
Journal of Cardiovascular Electrophysiology, 2003Co-Authors: Chern-en Chiang, Wen-chung Yu, Jun-jack Cheng, Yu-an Ding, Mau-song Chang, Shih-ann ChenAbstract:Introduction: The incidence of spontaneous transition of 2:1 AV block to 1:1 AV conduction during AV nodal Reentrant tachycardia has not been well reported. Among previous studies, controversy also existed about the site of the 2:1 AV block during AV nodal Reentrant tachycardia. Methods and Results: In patients with 2:1 AV block during AV nodal Reentrant tachycardia, the incidence of spontaneous transition of 2:1 AV block to 1:1 AV conduction and change of electrophysiologic properties during spontaneous transition were analyzed. Among the 20 patients with 2:1 AV block during AV nodal Reentrant tachycardia, a His-bundle potential was absent in blocked beats during 2:1 AV block in 8 patients, and the maximal amplitude of the His-bundle potential in the blocked beats was the same as that in the conducted beats in 4 patients and was significantly smaller than that in the conducted beats in 8 patients (0.49 ± 0.25 mV vs 0.16 ± 0.07 mV, P = 0.007). Spontaneous transition of 2:1 AV block to 1:1 AV conduction occurred in 15 (75%) of 20 patients with 2:1 AV block during AV nodal Reentrant tachycardia. Spontaneous transition of 2:1 AV block to 1:1 AV conduction was associated with transient right and/or left bundle branch block. The 1:1 AV conduction with transient bundle branch block was associated with significant His-ventricular (HV) interval prolongation (66 ± 19 ms) compared with 2:1 AV block (44 ± 6 ms, P < 0.01) and 1:1 AV conduction without bundle branch block (43 ± 6 ms, P < 0.01). Conclusion: The 2:1 AV block during AV nodal Reentrant tachycardia is functional; the level of block is demonstrated to be within or below the His bundle in a majority of patients with 2:1 AV block during AV nodal Reentrant tachycardia, and a minority are possibly high in the junction between the AV node and His bundle. (J Cardiovasc Electrophysiol, Vol. 14, pp. 1337-1341, December 2003)
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radiofrequency catheter ablation of sustained intra atrial Reentrant tachycardia in adult patients identification of electrophysiological characteristics and endocardial mapping techniques
Circulation, 1993Co-Authors: Shih-ann Chen, Chern-en Chiang, Chinjuey Yang, Chenchuan Cheng, Tsujuey Wu, Shihpu Wang, B N Chiang, Mau-song ChangAbstract:BACKGROUNDInformation about electrophysiological characteristics and radiofrequency ablation of intra-atrial Reentrant tachycardia has not been reported before. We proposed that induction and termination of intra-atrial Reentrant tachycardia by atrial extrastimuli or rapid atrial pacing and resetting the response pattern by atrial extrastimuli during intra-atrial Reentrant tachycardia could ensure the mechanism of reentry and that the earliest site of endocardial activation and concealed entrainment pace mapping with the shortest stimulus-P wave interval could localize a critical area responsible for intra-atrial Reentrant tachycardia and radiofrequency ablation.METHODS AND RESULTSSeven patients with refractory atrial tachycardia were referred for electrophysiological studies and radiofrequency ablation. Electrophysiological studies and endocardial mapping found (1) 10 atrial foci with atrial tachycardia cycle length of 406 +/- 41 ms; (2) atrial tachycardia had induction and termination by atrial extrasti...
Martin Borggrefe - One of the best experts on this subject based on the ideXlab platform.
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targeting the slow pathway for atrioventricular nodal Reentrant tachycardia initial results and long term follow up in 379 consecutive patients
European Heart Journal, 2001Co-Authors: J R Clague, Hans Kottkamp, Nikolaos Dagres, G Breithardt, Martin BorggrefeAbstract:Objectives This study is designed to examine the immediate and short-term outcomes of patients who have undergone slow pathway ablation/modification for atrioventricular nodal Reentrant tachycardia. Background Targeting the slow pathway has emerged as the superior form of treatment for atrioventricular nodal Reentrant tachycardia. This technique has been found effective and is associated with a low complication rate. However, little is known of the long-term outcome of patients undergoing this procedure. Methods Over a 40-month period the slow pathway was targeted in 379 consecutive patients with proven atrioventricular nodal Reentrant tachycardia. The case records of all patients were examined. Accurate follow-up data is available in 96% of patients a mean of 20·6 months after the procedure. Results The initial success rate was 97%. The incidence of complete heart block was 0·8% and the mean fluoroscopy duration was 27·3min. The recurrence rate was 6·9%. Age, number of pulses and fluoroscopy time were positively associated with either initial failure or recurrence. A total of 11·3% of patients were still taking antiarryhthmic medication at follow-up. Conclusions Targeting the slow pathway is an effective form of treatment for atrioventricular nodal Reentrant tachycardia. The technique has a high initial success rate, a low complication rate and a low recurrence rate at long-term follow-up. Slow pathway modification is associated with similar success rates and recurrence rates as slow pathway ablation and may confer theoretical long-term benefits.
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temperature controlled radiofrequency catheter ablation of accessory pathways and atrioventricular nodal Reentrant tachycardia the 5 french catheter approach
Journal of Cardiovascular Electrophysiology, 1996Co-Authors: Hans Kottkamp, Gerhard Hindricks, X Chen, Thomas Wichter, Stephan Willems, Sinnika Ylimayry, Gunter Breithardt, Martin BorggrefeAbstract:Ablation with Temperature-Controlled 5-French Catheters. Introduction: In the present study, we assessed the feasibility of radiofrequency (RF) ablation of accessory pathways and AV nodal Reentrant tachycardias with novel 5-French catheters with 4-mm tip electrodes using established mapping criteria and temperature-controlled power output control. Methods and Results: In this prospective study, 60 consecutive adult patients (mean age 36 ± 20 years) with accessory pathways (n = 37; 24 left-sided) or AV nodal Reentrant tachycardia (n = 23) underwent RF catheter ablation. A 5-French catheter with a 4-mm tip electrode and an embedded thermistor was used for RF application. The surface of the tip electrodes was 26 mm2 compared to 38 mm2 of 7-French catheters with 4-mm tip electrodes from the same catheter series. Power output was automatically and continuously adjusted according to the preset catheter tip temperature of 60° to 70°C. Pulse duration was 90 seconds. For left-sided accessory pathways, the retrograde route via the femoral artery was used. After removing the 5-French sheaths, only 4 hours of bed rest were advised. For ablation of AV nodal Reentrant tachycardia, the so-called slow pathway was targeted for ablation. Acute success was achieved in 34 (92%) of 37 patients with accessory pathways and 23 (100%) of 23 patients with AV nodal Reentrant tachycardia. A mean of 3 ± 4 RF pulses (median 2 pulses; range 1 to 20 pulses) was applied. The mean fluoroscopy time was 26 ± 21 minutes. No complete AV block or other procedure-related complications were observed. Recurrences occurred in 2 patients with accessory pathways and in 2 patients with AV nodal Reentrant tachycardia during a follow-up of 9 ± 4 months. Conclusions: Temperature-controlled RF ablation of accessory pathways and AV nodal Reentrant tachycardia in adults using 5-French catheters is feasible, effective, and safe. Ablation with 5-French catheters might help to reduce the complication rate of catheter ablation techniques.
