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Mausong Chang - One of the best experts on this subject based on the ideXlab platform.
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radiofrequency ablation induced asystole during transaortic approach for a left anterolateral Accessory Pathway a bezold jarisch like phenomenon
Journal of Cardiovascular Electrophysiology, 1997Co-Authors: Ching Fung Tsai, Shih Huang Lee, Ching T Tai, Shih A Chen, Chern E Chiang, Yi J Chen, Zu Chin Wen, Jin Long Huang, An Ning Feng, Mausong ChangAbstract:We present a case of cardiac asystole induced by radiofrequency catheter ablation of a left anterolateral Accessory Pathway in a 28-year-old woman with Wolff-Parkinson-White syndrome who was experiencing recurrent palpitation. Radiofrequency current applied on the ventricular aspect of the mitral annulus corresponding to the aforementioned site provoked profound slowing of the sinus rate preceded by disappearance of the preexcitation, and then asystole ensued. The proposed causal mechanism was a reflexogenically mediated hypotension-bradycardia syndrome (Bezold-Jarisch-like phenomenon) through stimulation of either nearby vagal afferent Pathways or sensory terminal receptors at the ablation site.
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a new electrocardiographic algorithm using retrograde p waves for differentiating atrioventricular node reentrant tachycardia from atrioventricular reciprocating tachycardia mediated by concealed Accessory Pathway
Journal of the American College of Cardiology, 1997Co-Authors: Ching T Tai, Shih Huang Lee, Chuen Wang Chiou, Kwo Chang Ueng, Shih A Chen, Chern E Chiang, Zu C Wen, Yi J Chen, Mausong ChangAbstract:Abstract Objectives. The purpose of this study was to use an electrocardiographic (ECG) algorithm, derived from the results of radiofrequency ablation, to discriminate atrioventricular node reentrant tachycardia (AVNRT) from atrioventricular reciprocating tachycardia (AVRT) and to localize a concealed Accessory Pathway, prospectively. Background. Information about ECG criteria for differentiating AVNRT from AVRT is limited and has not been confirmed by surgical or catheter ablation. Methods. Four hundred six ECGs (obtained from 406 different patients) that demonstrated narrow QRS complex ( 1 or pseudo S wave in inferior leads, or both, were examined, and the results were confirmed by radiofrequency catheter ablation. The initial 226 ECGs were analyzed to develop a stepwise algorithm, and the subsequent 180 ECGs were prospectively evaluated by the new algorithm. Results. The presence of a pseudo r′ wave in lead V 1 or a pseudo S wave in leads II, III, aVF indicated anterior-type AVNRT with an accuracy of 100%. With the difference of RP′ intervals in leads V 1 and III >20 ms, posterior-type AVNRT could be differentiated from AVRT utilizing a posteroseptal Pathway with a sensitivity of 71% (95% confidence interval [CI] 55% to 89%), a specificity of 87% (95% CI 67% to 97%) and a positive predictive value of 75% (95% CI 56% to 91%). According to the polarity of retrograde P waves in leads V 1 , II, III, aVF and I during AVRT, the concealed Accessory Pathway could be localized to one of the nine regions on the atrioventricular annuli with an accuracy of 75% (for a right midseptal Pathway) to 93.8% (for a left posterior Pathway). Overall, the new algorithm had an accuracy of 97.8% in discriminating AVNRT from AVRT and 88.1% in localizing a concealed Accessory Pathway, prospectively. Prediction was incorrect in only 15 patients (9.1%). Conclusions. The new ECG algorithm derived from the analysis of retrograde P waves during tachycardia could provide a criterion for differential diagnosis between AVNRT and AVRT and for predicting the location of concealed Accessory Pathways. (J Am Coll Cardiol 1997;29:394–402)
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Accessory Pathway and atrioventricular node reentrant tachycardia in elderly patients clinical features electrophysiologic characteristics and results of radiofrequency ablation
Journal of the American College of Cardiology, 1994Co-Authors: Shihann Chen, Chernen Chiang, Chinjuey Yang, Chenchuan Cheng, Shihpu Wang, Benjamin N Chiang, Mausong ChangAbstract:Abstract Objectives. This study was designed to evaluate the clinical features, electrophysiologic characteristics and results of radio-frequency ablation in elderly patients with Accessory atrioventricular (AV) Pathways or AV node reentrant tachycardia. Background. Radiofrequency ablation in elderly patients with paroxysmal supraventricular tachycardia has not been well described, and comparative study between elderly and younger patients is limited. Methods. Electrophysiologic studies and radiofrequency ablation were performed in 92 elderly patients (45 with an Accessory Pathway, 47 with AV node reentrant tachycardia). Results. The elderly patients had poorer electrophysiologic properties in Accessory Pathways and dual AV node Pathways than those of younger patients. The success rate of radiofrequency ablation was similar in elderly and younger patients. However, elderly patients had more complications (14%) in left-sided Accessory Pathways. Conclusions. Radiofrequency ablation in elderly patients with supraventricular tachycardia was effective. However, it must be performed cautiously in those patients with left-sided Accessory Pathways.
Gerhard Hindricks - One of the best experts on this subject based on the ideXlab platform.
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differentiating atrioventricular nodal reentrant tachycardia from tachycardia via concealed Accessory Pathway
American Journal of Cardiology, 2005Co-Authors: Arash Arya, Hans Kottkamp, Christopher Piorkowski, Petra Schirdewahn, Hildegard Tanner, Richard Kobza, Anja Dorszewski, Jinghong Gerdsli, Gerhard HindricksAbstract:Studies analyzing the diagnostic value of 12-lead electrocardiographic criteria differentiating slow-fast atrioventricular nodal reentrant tachycardia (AVNRT) from atrioventricular reentrant tachycardia (AVRT) due to concealed Accessory Pathway have shown inconsistent results. In 97 patients (50 with AVNRT, 47 with AVRT) 12-lead electrocardiograms (ECGs) were recorded during sinus rhythm and tachycardia (QRS /=2 mm with the number and location of the affected leads, QRS amplitude, and cycle length alternans.
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localization and radiofrequency catheter ablation of left sided Accessory Pathways during atrial fibrillation feasibility and electrogram criteria for identification of appropriate target sites
Journal of the American College of Cardiology, 1995Co-Authors: Gerhard Hindricks, Hans Kottkamp, X Chen, S Willems, Wilhelm Haverkamp, Mohammad Shenasa, Breithardt Gunter, Martin BorggrefeAbstract:OBJECTIVES: The purpose of the present study was to assess the feasibility of and electrophysiologic criteria for successful radiofrequency catheter ablation of left-sided Accessory Pathways during atrial fibrillation in patients with Wolff-Parkinson-White syndrome. BACKGROUND: The onset of recurrent or sustained atrial fibrillation can complicate or significantly prolong Accessory Pathway catheter ablation procedures. METHODS: We studied 19 consecutive patients (mean age [+/-SD] 44 +/- 16 years) with Wolff-Parkinson-White syndrome who had ongoing atrial fibrillation with rapid anterograde conduction over the Accessory Pathway (mean ventricular rate [+/-SD] 173 +/- 26 beats/min, range 130 to 220) at the beginning of the localization procedure during radiofrequency catheter ablation. Localization and ablation of the Accessory Pathway were performed with a 7F deflectable catheter (4-mm tip) that was placed underneath the mitral valve annulus. The electrophysiologic criteria from unipolar and bipolar local electrograms were compared for successful (n = 18) and unsuccessful (n = 39) sites. RESULTS: The Accessory Pathways were localized in the left posteroseptal (n = 6), posterior (n = 1), posterolateral (n = 7) and lateral (n = 5) regions and successfully ablated during atrial fibrillation in 18 (95%) of 19 patients with a mean of 3 +/- 2 radiofrequency pulses (range 1 to 8, median 2). Presence of an Accessory Pathway potential (94% vs. 44%), early activation time of the ventricular electrogram (-3.2 +/- 9.2 vs. -15.3 +/- 12.6 ms) and recording of atrial activation (88% vs. 61%) from the ablation catheter were helpful in identifying successful sites (p < 0.001, p < 0.001 and p < 0.05, respectively, compared with unsuccessful sites). In addition, the ventricular activation time in relation to the intrinsic deflection of the unipolar electrogram was significantly earlier at successful than unsuccessful sites (18.1 +/- 4.8 vs. 24.4 +/- 6.6 ms, p < 0.01). A QS complex on the unipolar electrogram was observed at 96% of successful sites and at 94% of unsuccessful sites (p = 0.74). Multivariate logistic regression analysis revealed that the presence of an Accessory Pathway potential (p < 0.002) and early ventricular activation time in relation to the onset of the QRS complex (p < 0.001) were independent predictors of ablation success. CONCLUSIONS: Localization and radiofrequency catheter ablation of left-sided Accessory Pathways is possible in patients with sustained atrial fibrillation and rapid anterograde conduction over the Accessory Pathway during the ablation procedure. The electrophysiologic criteria described here can be used to reliably identify successful sites for radiofrequency ablation.
Ching T Tai - One of the best experts on this subject based on the ideXlab platform.
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radiofrequency ablation induced asystole during transaortic approach for a left anterolateral Accessory Pathway a bezold jarisch like phenomenon
Journal of Cardiovascular Electrophysiology, 1997Co-Authors: Ching Fung Tsai, Shih Huang Lee, Ching T Tai, Shih A Chen, Chern E Chiang, Yi J Chen, Zu Chin Wen, Jin Long Huang, An Ning Feng, Mausong ChangAbstract:We present a case of cardiac asystole induced by radiofrequency catheter ablation of a left anterolateral Accessory Pathway in a 28-year-old woman with Wolff-Parkinson-White syndrome who was experiencing recurrent palpitation. Radiofrequency current applied on the ventricular aspect of the mitral annulus corresponding to the aforementioned site provoked profound slowing of the sinus rate preceded by disappearance of the preexcitation, and then asystole ensued. The proposed causal mechanism was a reflexogenically mediated hypotension-bradycardia syndrome (Bezold-Jarisch-like phenomenon) through stimulation of either nearby vagal afferent Pathways or sensory terminal receptors at the ablation site.
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a new electrocardiographic algorithm using retrograde p waves for differentiating atrioventricular node reentrant tachycardia from atrioventricular reciprocating tachycardia mediated by concealed Accessory Pathway
Journal of the American College of Cardiology, 1997Co-Authors: Ching T Tai, Shih Huang Lee, Chuen Wang Chiou, Kwo Chang Ueng, Shih A Chen, Chern E Chiang, Zu C Wen, Yi J Chen, Mausong ChangAbstract:Abstract Objectives. The purpose of this study was to use an electrocardiographic (ECG) algorithm, derived from the results of radiofrequency ablation, to discriminate atrioventricular node reentrant tachycardia (AVNRT) from atrioventricular reciprocating tachycardia (AVRT) and to localize a concealed Accessory Pathway, prospectively. Background. Information about ECG criteria for differentiating AVNRT from AVRT is limited and has not been confirmed by surgical or catheter ablation. Methods. Four hundred six ECGs (obtained from 406 different patients) that demonstrated narrow QRS complex ( 1 or pseudo S wave in inferior leads, or both, were examined, and the results were confirmed by radiofrequency catheter ablation. The initial 226 ECGs were analyzed to develop a stepwise algorithm, and the subsequent 180 ECGs were prospectively evaluated by the new algorithm. Results. The presence of a pseudo r′ wave in lead V 1 or a pseudo S wave in leads II, III, aVF indicated anterior-type AVNRT with an accuracy of 100%. With the difference of RP′ intervals in leads V 1 and III >20 ms, posterior-type AVNRT could be differentiated from AVRT utilizing a posteroseptal Pathway with a sensitivity of 71% (95% confidence interval [CI] 55% to 89%), a specificity of 87% (95% CI 67% to 97%) and a positive predictive value of 75% (95% CI 56% to 91%). According to the polarity of retrograde P waves in leads V 1 , II, III, aVF and I during AVRT, the concealed Accessory Pathway could be localized to one of the nine regions on the atrioventricular annuli with an accuracy of 75% (for a right midseptal Pathway) to 93.8% (for a left posterior Pathway). Overall, the new algorithm had an accuracy of 97.8% in discriminating AVNRT from AVRT and 88.1% in localizing a concealed Accessory Pathway, prospectively. Prediction was incorrect in only 15 patients (9.1%). Conclusions. The new ECG algorithm derived from the analysis of retrograde P waves during tachycardia could provide a criterion for differential diagnosis between AVNRT and AVRT and for predicting the location of concealed Accessory Pathways. (J Am Coll Cardiol 1997;29:394–402)
Steven J Kalbfleisch - One of the best experts on this subject based on the ideXlab platform.
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a single mahaim fiber causing both antidromic and orthodromic reciprocating tachycardia
Journal of Cardiovascular Electrophysiology, 2008Co-Authors: Steven J Kalbfleisch, Kathy Bowman, Ralph AugostiniAbstract:We describe the case of a 56-year-old woman referred for electrophysiological (EP) testing for medically refractory supraventricular arrhythmias. During the EP study, the patient was found to have a right free wall atriofasicular (Mahaim type) Accessory Pathway and an inducible left bundle morphology preexcited tachycardia secondary to antidromic reciprocating tachycardia. The patient also had an inducible narrow complex orthodromic reciprocating tachycardia (ORT). Mapping revealed that the earliest site of retrograde atrial activation during ORT was along the lateral tricuspid annulus. This was the same location where the atriofasicular Accessory Pathway potential was recorded during sinus rhythm. Radiofrequency ablation at this site eliminated inducibility of both tachycardias and any evidence of antegrade or retrograde Accessory Pathway conduction. This report describes the case of a very rare right free wall Mahaim type fiber with both antegrade and retrograde conduction capabilities responsible for both antidromic and ORT.
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recurrence of conduction in Accessory atrioventricular connections after initially successful radiofrequency catheter ablation
Journal of the American College of Cardiology, 1992Co-Authors: Jonathan J Langberg, Hugh Calkins, Youn Nyun Kim, Joao De Sousa, Rafel Elatassi, Angel Leon, Mark Borganelli, Steven J Kalbfleisch, Fred MoradyAbstract:Abstract The purpose of this study was to characterize the incidence and clinical features of Accessory Pathway recurrence after initially successful radiofrequency catheter ablation and to identify variables correlated with recurrence. Radiofrequency ablation was performed with a 7F deflectable tip catheter with a large (4 mm in length) distal electrode. Left-sided Accessory patthways were approached through the left ventricle and right-sided Pathways by way of the right atrium. Patients were included in the study if 1) they had an initially successful procedure, defined as the absence of Accessory Pathway conduction immediately after ablation, and 2) had undergone a 3-month follow-up electrophysiologic test or had documented recurrence of Accessory Pathway conduction. Accessory Pathway conduction recurred after initially successful ablation in 16 (12%) of 130 patients. Almost half (7 of 16) of these recurrences were in the 1st 12 h after ablation, and the last occurred after 106 days. Return of delta waves on the electrocardiogram (ECG) or spontaneous paroxysmal supraventricular tachycardia was the initial indication of recurrence in 15 of the 16 patients. Two patients with manifest Accessory Pathways exhibited recurrence with exclusively concealed Accessory Pathway conduction. Accessory Pathways ablated from the tricuspid anulus (right free wall or septal Accessory Pathways) had a much higher recurrence rate (24%) than did those on the mitral anulus (6%). Fourteen of 15 patients have had successful repeat Accessory Pathway ablation after the initial recurrence. After a mean follow-up period of 4 ± 3 months, there have been no repeat recurrences of any of these Accessory Pathways. It is concluded that Accessory Pathway recurrence is infrequent after successful radiofrequency catheter ablation. All but one episode of recurrence was diagnosed clinically, suggesting that routine follow-up electrophysiologic testing in asymptomatic patients is not warranted. Because manifest Accessory Pathways may recur with retrograde conduction only, patients with palpitation after ablation should have electrophysiologic testing even if no delta waves are seen on the ECG. The success rate of ablation after recurrence (93%) is comparable to that achieved at the initial session, suggesting that return of Accessory Pathway function should not be a contraindication to a repeat attempt.
Robert M Gow - One of the best experts on this subject based on the ideXlab platform.
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electrocardiographic differentiation of typical atrioventricular node reentrant tachycardia from atrioventricular reciprocating tachycardia mediated by concealed Accessory Pathway in children
American Journal of Cardiology, 2003Co-Authors: Edgar Jaeggi, Thomas Gilljam, Urs Bauersfeld, Christine L Chiu, Robert M GowAbstract:Abstract The value of the electrocardiogram (ECG) in children with supraventricular tachycardia (SVT) is unclear. The noninvasive differentiation of typical atrioventricular node reentrant tachycardia (AVNRT) and atrioventricular reciprocating tachycardia (AVRT) mediated by concealed Accessory Pathway conduction is clinically important, as it helps in counseling and potentially facilitates ablation procedures. One hundred forty-eight ECGs showing narrow QRS complex SVT were obtained from children before successful radiofrequency catheter ablation. An initial 102 ECGs were analyzed by 3 blinded observers to assess the utility of various electrocardiographic findings. No electrocardiographic criteria were found to discriminate between SVT mechanisms on 1- to 3-channel Holter/event recorder tracings (n = 32); their interpretation mainly (55%) resulted in an incorrect SVT diagnosis. On 12-lead ECGs (n = 70), the 2 arrhythmias were accurately diagnosed in 76% of patients; 5 findings were found to be discriminators of tachycardia mechanism. Predictors of AVRT were visible P waves in 74% of cases (sensitivity 92%; specificity 64%), RP intervals of ≥100 ms in 91% (sensitivity 84%; specificity 91%), and ST-segment depression of ≥2 mm in 73% of cases (sensitivity 52%; specificity 82%). Pseudo r′ waves in lead V1 and pseudo S waves in the inferior leads during tachycardia predicted AVNRT in 100% of cases (sensitivity 55% and 20%, respectively; specificity 100% for both). Based on these results, we developed a new diagnostic 12-lead electrocardiographic algorithm for pseudo r′/S waves, RP duration, and ST-segment depression during tachycardia. Two observers tested the algorithm in 46 (21 AVNRT; 25 AVRT) additional cases; they correctly diagnosed the SVT mechanism in 91% and 87%, respectively. Thus, the stepwise use of diagnostically relevant 12-lead electrocardiographic parameters helps to more accurately differentiate mechanisms of reentrant SVT.