Anomalía de Ebstein y aneurisma del seno coronario / Ebstein’s anomaly and coronary sinus aneurysm

Resumen La anomalía de Ebstein es una cardiopatía congénita poco común que se asocia a la presencia de vías de conducción anómalas y episodios de taquicardia supraventricular frecuentes, algunos inestables. La asociación con alteraciones anatómicas del seno coronario es rara y no ha sido reportada. Se presenta el caso de una paciente de 58 años con enfermedad coronaria, anomalía de Ebstein, episodios de taquicardia ortodrómica y aneurisma del seno coronario, a quien se realizó ablación.

Abstract Ebstein’s disease is a congenital cardiomyopathy, with a low prevalence in the general population. This abnormality has been associated with abnormal cardiac conduction problems, one of the most important being the accessory pathways. In the presence of an accessory pathway, frequent supraventricular tachycardias may occur, some of which are poorly tolerated. The association with the anomalies of the coronary sinus is not currently reported. The case of a 58-year-old woman with Ebstein’s disease, episodes of supraventricular tachycardia, and coronary sinus aneurysm undergoing ablation therapy is presented.

Wolff-Parkinson-White syndrome in a man presenting with palpitation – A case report

Wolff-Parkinson-White (WPW) syndrome is not a common presentation, but physicians get to see cases with pre-excitation syndrome. WPW is characterized by the existence of an accessory pathway that predisposes patients to tachyarrhythmias and sudden death. Patients with WPW syndrome are at greater risk of hazardous ventricular arrhythmias. The majority of the cases never present with an underlying structural cardiac disease. It is always controversial to manage asymptomatic patients with WPW syndrome. Here, we discuss an uncommon case of a 48-year-old man with WPW syndrome after being evaluated for palpitation and giddiness.

Application of transseptal puncture to radiofrequency catheter ablation in children with left accessory pathway induced paroxysmal supraventricular tachycardia / 中华实用儿科临床杂志

Objective To explore the value of transseptal puncture for left-sided accessory pathway in radio-frequency catheter ablation in children with paroxysmal supraventricular tachycardia(PSVT). Methods Thirty-three patients with PSVT who had underwent radiofrequency catheter ablation in the First Affiliated Hospital,Sun Yat-Sen University from January 2012 to December 2017 were retrospectively analyzed. All the cases were treated by transaortic approach(transaortic group)or transseptal approach(transseptal group). The immediate success rates,total fluoroscopy time and radiation exposure between 2 groups were compared,and the perioperative complications and recurrence rates were observed between 2 groups. Results Thirty-three cases of children were enrolled,22 cases were male and 11 cases were female. Nineteen cases were treated by transaortic approach(transaortic group),while 18 cases were treated by transseptal approach(transseptal group),including 4 recurrent cases in the transaortic group who were switched to transseptal approach because of previous treatment failure. The age was(10. 16 ± 3. 06)years and(10. 67 ± 2. 20) years,and the weight was(37. 68 ± 14. 28)kg and(37. 33 ± 8. 64)kg,respectively. There were no significant diffe-rences in age and weight statistics between 2 groups(all P>0. 05). The total fluoroscopy time was(20. 16 ± 11. 41) minutes and(12. 56 ± 5. 23)minutes,and the median dose of radiation exposure was 67. 0 mGy and 33. 5 mGy,re-spectively. The postoperative recurrence rate was 21%(4/19 cases)and 0(0/18 cases),respectively. There were sig-nificant differences in total fluoroscopy time,radiation exposure and recurrence rate statistics between 2 groups( t ＝2. 627,Z＝ -2. 31,χ2 ＝4. 249,all P<0. 05). No complications were found in both 2 groups. Conclusions It is safe and feasible by transseptal puncture for left-sided accessory pathway in radiofrequency catheter ablation in children with PSVT. Radiofrequency catheter ablation by transseptal approach could significantly reduce the postoperative recu-rrence rate,and should be the first choice for left-side accessory pathway in children.

Clinical and prognostic analysis of accessory pathway-induced dilated cardiomyopathy after catheter ablation in children / 中华心血管病杂志

Objective@#To investigate the clinical characteristics and prognostic factors after catheter ablation of accessory pathway (AP)-induced dilated cardiomyopathy (DCM) in children.@*Methods@#Data were collected and analyzed on 147 consecutive pediatric patients (81males and 66 females), who hospitalized in our pediatric heart center between January 2009 and August 2018 and received catheter ablation for ventricular pre-excitation (right AP). Thirty-one children were diagnosed as AP-induced DCM and 116 children with normal cardiac function served as control. Data including clinical characteristics, electrocardiogram (ECG), echocardiography, electrophysiological examination (EPS), successful ablation and follow up were analyzed.@*Results@#The median age at first examination was 3.07 (0.09, 5.83) years. The pre-hospital misdiagnosis rate was 87.1% (27/31). The incidence of the AP-induced DCM was 21.1% (31/147) and the rate of right anterior free wall accessory pathway (AP) was the highest (50.0%, 10/20). AP-induced DCM was more common in right free wall Aps (41.9%, 13/31) and right anterior free wall (32.3%, 10/31). 48.4% (15/31) cases had no supraventricular tachycardia (SVT). EPS showed that 29% (9/31) of the AP did not have retrograde conduction. The median follow-up time after successful catheter ablation was 8 (2, 36) months of AP-induced DCM group, LVDd was significantly decreased ((41.6±12.8)mm vs. (45.6±13.9)mm, P<0.01) and LVEF ((56.2±11.8)% vs. (40.8±12.5)%, P<0.01) was significantly increased after ablation. Cox regression analysis showed that LVEF was the predictor of the duration of cardiac function recovery (HR=1.08, 95%CI 1.01-1.15, P=0.03).@*Conclusions@#Misdiagnosis rate is high for children with AP-induced DCM, leading to the delayed treatment. All of the AP-induced DCM occurred in right APs and right anterior free wall APs is the highest. Right free wall APs and right anterior free wall are most common in AP-induced DCM. Catheter ablation is a safe and effective treatment option for these patients. The lower the LVEF, the longer the cardiac function recovery.

Local Atrial/Ventricular Ratio as an Adjuvant Marker for Catheter Ablation of Atrioventricular Accessory Pathways

BACKGROUND AND OBJECTIVES: The earliest atrial (A)/ventricular (V) activation potential, or accessory pathway (AP) potential are commonly used as ablation targets for atrioventricular (AV) APs. However, these targets are sometimes ambiguous. SUBJECTS AND METHODS: We reviewed 119 catheter ablation cases in 112 patients diagnosed with orthodromic atrioventricular reentrant tachycardia (AVRT) or Wolff-Parkinson-White (WPW) syndrome. Local A/V amplitude potentials with the earliest activation or AP potential were measured shortly before achieving antegrade AP conduction block, ventriculoatrial block during right ventricle (RV) pacing, or AVRT termination with no AP conduction. RESULTS: APs were located in the left lateral (55.5%), left posterior (17.6%), left posteroseptal (10.1%), midseptal (1.7%), right posteroseptal (7.6%), right posterior (1.7%), and right lateral (5.9%) regions. The mean earliest activation time was 16.7±15.5 ms, mean A/V potential was 1.1±0.9/1.0±0.9 mV, and mean A/V ratio was 1.7±2.0. There was no statistically significant difference between the activation methods (antegrade vs. RV pacing vs. orthodromic AVRT) or AP locations (left vs. right atrium). However, when the local A/V ratio was divided into 3 groups (≤0.6, 1.0±0.3, and ≥1.4), the antegrade approach resulted in an A/V ratio greater than 1.0±0.3 (86.7%, p=0.007), and the orthodromic AVRT state resulted in a ratio of less than 1.0±0.3 (87.5%, p<0.001). CONCLUSION: The mean local A/V potential and ratio did not differ by activation method or AP location. However, a different A/V ratio based on activation method (≥1.0±0.3, antegrade approach; and ≤1.0±0.3, orthodromic AVRT state) could be a good adjuvant marker for targeting AV APs.

Dos décadas de seguimiento exitoso de la primera ablación de arritmias por catéter de radiofrecuencia realizado en la historia de la medicina del Paraguay / Two decades of succesful follow-up of the first radiofrequency catheter arrhythmia ablation done in the history of medicine in Paraguay

La técnica de mapeo endocárdico durante el estudio electrofisiológico ha sido extensamente empleada en el análisis de las taquicardias paroxísticas supraventriculares (TPS). Mediante este mapeo endocárdico y el análisis meticuloso de los electrogramas endocárdicos y los respectivos intervalos de conducción, es posible localizar el sitio de origen de las arritmias y así facilitar su tratamiento ablativo por medio de catéteres de radiofrecuencia. Se describe el caso de un hombre de 29 años con síndrome de Wolff-Parkinson-White (WPW) que manifiestó que presentaba varios episodios documentados de TPS con serio compromiso hemodinámico que motivaba su frecuente internación en terapia intensiva. El mapeo electrofisiológico endocárdico meticuloso demostró la presencia de un haz anómalo de Kent auriculoventricular izquierdo en posición posteroseptal. El período refractario absoluto del haz anómalo de Kent fue de 240 ms. La primera emisión de radiofrecuencia a través de un catéter adecuadamente posicionado previo terminó la taquicardia. La taquicardia permaneció no inducible a partir de entonces. En estas dos décadas de seguimiento clínico, el paciente no ha presentado ni un solo episodio de taquicardia. La curación definitiva generada por la ablación del haz anómalo de Kent ha proporcionado un cambio drástico, total y beneficioso en la calidad de vida al paciente. Los beneficios clínicos y socioeconómicos son mayores cuanto más temprano en la evolución se realice el procedimiento de ablación de arritmias.

Endocardial mapping has been widely used for the analysis of supraventriculartachycardias during electrophysiological study. This mapping and the detailed analysis ofendocardial electrograms and conduction intervals allow for the localization of the site oforigin of the arrhythmias thus facilitating curative treatment with radiofrequency catheterablation. The case describes our 29 years old patient with manifested Wolff-ParkinsonWhitesyndrome that presented frequent, documented episodes of paroxysmal supraventricular tachycardia with serious hemodynamic alteration that needed frequentadmissions to intensive care units despite the use of 2-3 antiarrhythmic agents per day. Adetailed endocardial mapping showed a left posteroseptal accessory pathway. Theaccessory pathway effective refractory period is 240 ms. The first radiofrequency emissionthrough an adequately positioned radiofrequency catheter terminated the tachycardia. Thetachycardia was rendered non-inducible thereafter. In two decades of follow-up, the patienthas not presented a single episode of tachycardia. The definite cure provided by theradiofrequency ablation produced a total, dramatic, and beneficial change in the quality oflife of the patient. The clinical and socio-economical benefits are greater the earlier thearrhythmia ablation procedure is performed.

Clinical research on radiofrequency catheter ablation for treating epicardial accessory pathway / 重庆医学

Objective To investigate the efficacy and safety of radiofrequency catheter ablation for treating epicardial accessory pathway .Methods 8 patients with unsuccessful endocardial ablation of accessory pathway were mapped within coronary venous si-nus or middle cardiac vein and the radiofrequency catheter ablation was performed by the temperature control electrode .Results Ablation in 8 cases was successfully performed within coronary sinus or middle cardiac vein .There were no complications in all pa-tients .Conclusion Radiofrequency catheter ablation of epicardial accessory pathway within coronary sinus and middle cardiac vein is safe and effective .

La electrofisiología del Wolff-Parkinson-White en el paciente asintomático con actividad o riesgo profesional alto / The electrophysiology of Wolff-Parkinson-White in the asymptomatic patient with activity or with high professional risk

Objetivo: Describir las características electrofisiológicas en individuos con Wolff-Parkinson-White asintomático con actividad deportiva o alta responsabilidad profesional. Métodos: Se evaluaron 19 individuos, edad media 33 ± 13 años (grupo A). Las características electrofisiológicas fueron comparadas con un grupo control similar con WPW sintomático (grupo B). Resultados: En estado basal el periodo refractario anterógrado y la conducción anterógrada 1:1 sobre el fascículo accesorio fueron más largos en el grupo A (300 ± 48 ms vs 262 ± 32 ms, p < 0.05) y (355 ± 108 ms vs 307 ± 86 ms, p < 0.05), respectivamente. Ningún individuo del grupo A tuvo un periodo refractario anterógrado < 250 ms; y 58% no tuvieron conducción retrógrada sobre el fascículo accesorio vs 4% del grupo B (p< 0.001). La inducción de taquicardia fue significativamente menor (5.2%) en el grupo A vs grupo B (95%) (p < 0.001). Se indujo fibrilación auricular (FA) sólo en uno del grupo A vs en 32% grupo B (p< 0.001). Conclusión: Se confirman las características electrofisiológicas benignas en individuos asintomáticos comparados con sintomáticos. La deficiente conducción anterógrada junto con ausencia de conducción retrógrada explica la baja frecuencia de taquiarritmias y no apoyaría la investigación rutinaria en toda la población asintomática, pero debido a las posibles consecuencias, se mantiene la indicación sistemática con fines de ablación preventiva en el subgrupo de individuos asintomáticos con actividad deportiva o alta responsabilidad profesional.

Objective: Describe the electrophysiological characteristics in subjects with asymptomatic Wolff-Parkinson-White with sports activities or high professional responsibility. Methods: Nineteen subjects, mean age 33 ± 13 years (group A). The electrophysiological characteristics were compared with a matched group with symptomatic WPW (group B). Results: At baseline the anterograde refractory period and the anterograde conduction 1:1 over the accessory pathway were longer in group A (300 ± 48 ms vs 262 ± 32 ms, p <0.05 and 355 ± 108 ms vs 307 ± 86 ms, p <0.05), respectively. None of group A had a anterograde refractory period < 250 ms and 58% showed absence of retrograde conduction over the accessory pathway vs 4% of group B (p < 0.001). Induction of tachycardia was significantly less in group A (5%) than in group B (92%) (p < 0.001). Atrial fibrillation was induced in only one of group A vs 32% of group B (p< 0.001). Conclusion: We confirm the benign electrophysiological characteristics in asymptomatic compared to symptomatic subjects. Poor anterograde conduction along with absence of retrograde conduction explains the low frequency of tachyarrhythmias and would not support the routine investigation of all asymptomatic subjects. But, due to possible consequences, remains the systematic indication for preventive ablation in the subgroup of asymptomatic subjects with sporting activities or high professional responsibility.

Radiofrequency Catheter Ablation of Left Free Wall Accessory Pathways: Comparison Between Retrograde and Transeptal Approach.

Background : This study was conducted to compare the conventional retrograde arterial approach (RAA) with the transeptal approach (TSA) for radiofrequency catheter ablation (RFA) of left accessory pathways (AP). Materials and Methods: Sixty consecutive patients (44 male; mean age of 35.60 ± 11.63 years) with 60 left APs (39 overt and 21 concealed) underwent catheter ablation using the TS method (30 patients) and the RA method (30 patients) in an alternate fashion. The analysis was performed according to the intention-to-treat principle. Results : The transeptal puncture was successfully performed in 29 patients (96%). This access allowed primary success in the ablation in all the patients without any complication. When we compared this approach with the RAA there was no difference as regards the primary success (p = 0.103), fluoroscopy time (p = 0.565) and total time (p = 0.1917). Three patient in the RAA group presented a vascular complication. The TSA allowed shorter ablation times (p=0.006) and smaller number of radiofrequency applications (p = 0.042) as compared to the conventional RAA. The patients who had unsuccessful ablation in the first session in each approach underwent with the opposite technique (cross-over), with a final ablation success rate of 100%. Conclusion : The TS and RA approaches showed similar efficacy and safety for the ablation of left accessory pathways. The TSA allowed shorter ablation times and smaller number of radiofrequency applications. When the techniques were used in a complementary fashion, they increased the final efficacy of the ablation.

Electrophysiological characteristics and catheter ablation left-sided accessory pathways of Mahaim fiber / 中国医师进修杂志

ObjectiveTo study electrophysiological characteristics and catheter ablation left-sided accessory pathways of Mahaim fiber.MethodsTwenty-eight patients underwent catheter ablation for Mabaim fiber and 3 patients was left-sided accessory pathways.All of them were male with 34,20,38 years old.The tachycardia history was1-5years. Electrophysiological characteristics,target sitesand electrocardiogram(ECG,12 leads) were recorded through catheter from coronary sinus(CS),high right atrium(HRA),His bundle and ablation.ResultsOne patient's ECG showed little preexcitation,the other two were normal. Atrial stimulation could be easily induced tachycardia.Their ECG showed wide QRS waves (right bundle branch block or similar right bundle branch block).The characteristics of accessory pathways were slow and anterograde decremental conduction as well as blocked by adenosine triphosphate injection.Ventricular-atrial conduction was via atrioventricular node with centripetal decreasing transmission during ventricular pacing.During tachycardia,the His bundle electrogram resulted in a V-H-A pattern,the retrograde A in His bundle was pioneer.The atriofascicular pathways of 2 patients were completely ablated respectively in left posterior lateral and before the free wall of mitral valve ring.The nodoventricular pathway of 1 patient was successfully ablated in left middle posterior lateral of mitral valve ring.ConclusionsThe left-sided accessory pathways of Mahaim fiber is an uncommon accessory pathway,which has specific electrophysiological characteristics.It is effective and safe to ablate accessory pathway with radiofrequency.

Ablación transquirúrgica de vía accesoria atrioventricular en anomalía de Ebstein / Surgical radioerequency catheter ablation of accessory pathways in Ebstein's anomaly

Fueron estudiados 13 pacientes con anomalía de Ebstein con taquicardia por reentrada atrioventricular y al menos una vía accesoria. En 7 pacientes (53.8%) existía una vía accesoria y en 6 pacientes (46.1%) vías múltiples. En 5 pacientes (38.4%) se encontró vía accesoria tipo Mahaim. Un total de 22 vías accesorias fueron identificadas de las cuales 2 (9%) eran ocultas. El 100% se localizaron en el anillo tricuspídeo. Los sitios más frecuentes de ubicación fueron: región lateral derecha con 11 (50%) y postero-septal derecha con 5 (22.7%). Diez pacientes recibieron tratamiento mediante ablación con radiofrecuencia vía transquirúrgica y tres mediante sección quirúrgica. Se obtuvo un éxito de 100%. No se presentaron complicaciones durante los procedimientos. Conclusión: La ablación transquirúrgica de vías accesorias atrioventriculares en pacientes con anomalía de Ebstein es un procedimiento seguro y eficaz.

Thirteen patients with Ebstein anomaly and atrioventricular reentrant tachycardia and at least one accessory pathway were included in this study. One accessory pathway in 7 (53.8%) patients and multiple accessory pathways in 6 (46.1%) were found. Mahaim accessory pathway was observed in 5 (38.4%) patients. A total of 22 accessory pathways was found, 2 (9%) were concealed. In all (100%), the accessory pathways were located in the tricuspid ring. The most frequent regions were right lateral free wall with 11 (50%) and 5 right posteroseptal (22.7%). Ten patients underwent surgical radiofrequency catheter ablation and three subjected to surgical section. We obtained success in 100%. No complications were observed during the procedures. In conclusion, surgical ablation therapy in patients with accessory pathways and Ebstein's anomaly is safe and effective.

Abnormal Perfusion on Myocardial Perfusion SPECT in Patients with Wolff-Parkinson-White Syndrome / 대한핵의학회잡지

PURPOSE: Abnormal myocardial perfusion may be caused by ventricular preexcitation, but its location, extent, severity and correlation with accessory pathway (AP) are not established. We evaluated perfusion patterns on myocardial perfusion SPECT and location of AP in patients with WPW (Wolff-Parkinson-White) syndrome. MATERIALS AND METHODS: Adenosine Tc-99m MIBI or Tl-201 myocardial perfusion SPECT was performed in 11 patients with WPW syndrome. Perfusion defects (PD) were compared to AP location based on ECG with Fitzpatrick's algorithm or electrophysiologic study and radiofrequency catheter ablation. RESULTS: Patients had atypical chest discomfort or no symptom. Risk of coronary artery disease (CAD) was below 0.1 in 11 patients using the nomogram to estimate the probability of CAD. Coronary angiography was performed in 4 patients (mid-LAD 50% in one, normal in others). In 4 patients, AP localization was done by electrophysiologic study and radiofrequency catheter ablation (RFCA). Small to large extent (11.0 +/- 8.5%, range: 3~35%) and mild to moderate severity (-71 +/- 42.7%, range: -217~-39%) of reversible (n=9) or fixed (n=1) perfusion defects were noted. One patient with right free wall (right lateral) AP showed normal. PD locations were variable following the location of AP. One patient with left lateral wall AP was followed 6 weeks after RFCA and showed significantly decreased PD on SPECT with successful ablation. CONCLUSION: Myocardial perfusion defect showed variable extent, severity and location in patients with WPW syndrome. Abnormal perfusion defect showed in most of all patients, but it did not seem to be correlated specifically with location of accessory pathway and coronary artery disease. Therefore myocardial perfusion SPECT should be interpreted carefully in patients with WPW syndrome.

Seguimiento a largo plazo en 413 pacientes con vía accesoria atrioventricular sometidos a ablación con radiofrecuencia

Objetivo: se analizan los resultados clínicos y el seguimiento a largo plazo de los pacientes que fueron sometidos a ablación endocárdica mediante radiofrecuencia para el tratamiento de la taquicardia paroxística supraventricular por vía accesoria atrioventricular. Material y métodos: se incluyeron 413 pacientes a quienes se les realizó ablación con radiofrecuencia de vías accesorias atrioventricular de abril de 1992 a diciembre de 1995. Resultados: de los 413 pacientes seleccionados, 234 (57%) eran hombres y 179 (43%) eran mujeres, con edad promedio de 31.3 ± 16.3 años (límites 2 a 69 años). Se localizó un total de 437 vías accesorias atrioventriculares, 389 (93)% eran únicas y en 24 enfermos estuvieron presentes dos vías accesorias. La ablación tuvo éxito inmediato en 381 vías atrioventriculares (87%), durante el seguimiento promedio de siete años, se observó recurrencia de 51 vías atrioventriculares (13%), de estas 41 (80%) recurrieron en los primeros tres meses. A cincuenta y seis pacientes se les realizó una segunda sesión de ablación, con éxito de 35 (62.5%) y nueva recurrencia en 2 (5.7%). Son 365 vías accesorias (83.5) que permanecen sin recurrencia de taquicardia o preexcitación. Conclusiones: durante el seguimiento, los efectos de la ablación exitosa con RF se preservan en el tiempo. La taquicardia identificada en recurrencia siempre correspondió al mecanismo de reentrada a través de la vía accesoria.

Objective: the aim of this study was shown clinical characteristics and follow-up of patients with atrioventricular reentrant tachycardia (AVRT) who underwent radiofrequency catheter ablation (RCA) therapy. Material and Methods: from April 1992 to December 1995, 413 patients with AVRT underwent RCA therapy. Results: two hundred thirty four men (57%) and one hundred seventy nine women (43%) aged 31.3 ± 16-3 years were studied. 437 single accessory pathways were found; 24 had multiple accessory pathways. Ablation therapy was successful in 381 accessory pathways. During follow-up of 7 years, AVRT recurred in 51 patients (13%) and in 80% this occurred within the first 3 months after the procedure. 56 patients underwent a second RCA therapy with success in 35 patients (83.5); two reoccurred (5.7%); 365 accessory pathways (83.5) remained without evidence of preexcitation AVRT. Conclusions: during follow-up, these patients with successful ablation therapy remained without symptoms. In patients who underwent a second RCA therapy, atrioventricular reentrant mechanism was always present.

Clinical Study of Adenosine Triphosphate in Terminal Point Determining of Radiofrequency Catheter Ablation / 中国医师杂志

3S in 2 cases(5 7%).Ventriculoatrial conduction block was observed in 27 cases(77 1%) and no changes in 6 cases(14 3%) under the pace of right ventricular.Conclusions ATP is a determing index of successful RFCA of AP.However,it is not always reliable,incremental doses of ATP were recommended.

A COMPARISON OF HEAD-CHEST LEAD AND ROUTINE WILSON'S LEAD IN LOCALIZATION OF RIGHT DOMINANT BYPATH BY ECG ON BODY SURFACE / 解放军医学杂志

0.05), and HC lead ECG was more useful than Wilson lead when applied to localize the right free wall and right-anteroseptal accessory pathway (P

Effective Approaches to Successful Target Sites in Catheter Ablation of the Right-side Accessory Pathways / 대한내과학회지

BACKGROUND: Although radiofrequency catheter ablation (CA) of the accessory pathway (AP) is very effective and safe, it has been reported that CA is more difficult in the right-side AP than the left-side AP, requiring the refinement of the conventional CA technique for the right-side AP. This study was, therefore, aimed to develop an effective technique for CA of the right-side AP. METHODS: Fifty right-side APs in 45 patients which underwent CA were included in this study. The locations of APs were divided into 8 regions (anteroseptal, mid septal, posteroseptal, posterior, posterolateral, lateral, anterolateral, and anterior). After localizing APs, CA of the APs was attempted via the inferior vena cava (IVC) in all patients. If CA attempt via the IVC for more than 1 hour was failed, then CA was tried via the superior vena cava (SVC). Successful CA was defined as permanent loss of AP conduction even during infusion of isoproterenol (1-4microg/min). The ways of approaching the ablation catheter to the successful target sites were classified into over-the-tricuspid valve approach (OV) via the IVC (IVC-OV), OV via the SVC (SVC-OV), under-the-tricuspid valve (UV) approach via the IVC (IVC-UV), and UV via the SVC (SVC-UV) and evaluated according to the AP locations. RESULTS: The locations of the APs were anteroseptal in 5 APs, mid septal in 6, posteroseptal in 12, posterior in 3, posterolateral in 5, right lateral in 11, anterolateral in 4, and anterior in 4. Forty-eight (96.0%) of 50 APs were successfully ablated; 35 (70.0%) with primary IVC approaches and 13 (26.0%) with secondary SVC approaches. As a successful approach, IVC-OV was 26 (54.2%); IVC-UV, 9 (18.8%); SVC-OV, 4 (8.3%), and SVC-UV, 9 (18.8%). Secondary SVC approaches were required 7 (70.0%) in the lateral APs, 2 (50.0%) in the anterolateral APs, 1 (25.0%) of the posterolateral APs, 1 (25.0%) in the anterior APs, 1 (20.0%) of the anteroseptal APs, and 1 (8.3%) in the posteroseptal APs but none in the midseptal and posterior APs. SVC-UV approach was used in 9 (69.2%) in 13 APs which were ablated with SVC approach. CONCLUSIONS: The ways of approach to successful target site in CA of the right-side APs are different according to the location and SVC approaches are frequently required in ablation of the lateral or anterolateral APs. Therefore, SVC approaches should be considered in these locations if the initial IVC approaches are not successful.

The characteristics and radiofrequency catheter ablation of supraventricular tachycardia affiliated with rate-dependent concealed atrioventricular pathway / 中国介入心脏病学杂志

Objective To investigate characteristics of supraventricular tachycardia affiliated with rate-dependent concealed accessory pathway and the results of radiofrequency catheter ablation (RFCA). Methods Six patients (including 4 females and 2 males, agd from 14 to 68 years) had received electrophysiologic studies and RFCA, which included observing the properties of ventriculoatrial conduction while incremental pacing (S 1S 1) and single extrastimuli (S 1S 2) were performed in right ventricular apex (RVA) and left ventricle (LV), investigating the characteristics of tachycardia, mapping accessory pathway and evaluating the results from RFCA. Results There were 5 left free wall concealed accessory pathways and 1 right concealed accessory pathway at 11 o′clock of tricuspid valve in 6 patients. Five cases were confirmed with 1∶1 ventriculoatrial conduction through the concealed accessory pathway from RVA or LV pacing. The duration of the window ranged from 80 to 100 ms. Four cases were confirmed with accidental retrogradation through the concealed accessory pathway. The supraventricular tachycardia could be induced in 5 cases. All patients were successfully ablated from RVA pacing. Conclusion These results suggest that ventriculoatrial conduction would be rate-dependent because concealed accessory pathway takes place at phase block 3 or 4. In electrophysiologic studies we shoud carefully identify the accidental retrogradation through the concealed accessory pathway to avoid missed diagnosis.

Radiofrequency ablation for Para-Hisian accessory pathways / 中国介入心脏病学杂志

Para-Hisian accessory pathway (AP) means the AP locate about 0. 5cm above or under the His bundle. To identify the AP location,the big tip catheter mapping must be under sinus rhythm,ventricular pacing and inducing SVT in order to avoid injury of His bundle. During ablation process, the surface morphology and juctional escape rhythm must be observed. If RF must be done under ventricular pacing, once ablating effect is confirmed,the pacing would be stopped and escape rhythm can be observed. If ante-grade condution are always through AP in SVT and endocardial mapping are confirmed multipe APs and AVN are bystander in SVT, we do not exclude abmormal growth in AVN. It can be ablated retrograde AP to treat SVT and should be avoided to ablate antigrade AP.

Radiofrequency Catheter Ablation for the Treatment of Atrioventricular Reentrant Tachycardia

BACKGROUND: Atrioventricular reentry is the most common cause of supraventricular tachycardia in Korea. Radiofrequency catheter ablation(RFCA) is now accepted to be the safe and effective treatment modality for the elimination ofr accessory pathway conduction in patient with atrioventricualr reentrant tachycardia(AVRT). METHODS: To evaluate the clinical usefulness of RFCA for the treatment of AVRT, this study was conducted in 109 patients(male 68, female 41) with atrioventricular accessory pathway and documented AVRT after electrophysiologic study. RESULTS: A total of 112 accessory pathways were identified in 109 patients. The mean power outputs of the successful ablations at the atrial side of the annulus were higher than those at the ventricular side(34.0+/-8.9W versus 20.0+/-7.6W, p<0.01), but the maximum temperatures were lower at the atrial side of the annulus than those at the ventricular side (66.4+/-14.0degrees C versus 77.2+/-6.4degrees C, p<0.01). Accessory pathway conduction was eliminated in 102 of 112 pathways successfully(success rate 91v). There were 4 nonfatal complications(3.7%). 3 patients with hemopericardium and 1 with femoral artery thrombus, during or after ablation porcedures. Recurrences of AV reentrant tachycardia or delta wave on the electrocardiogram occured in 5 patients, and 4 of them had successful second procedures. There were no late complications during a mean follow-up period of 13+/-5 months. CONCLUSION: RFCA is highly effective and safe treatment modality in ablation accessory pathway conduction.

The Value of Ventriculoatrial Intervals in Determining the Mechanism of PSVT and the Sites of Accessory Pathways

The ventriculoatrial(VA) intervals during supraventricular tachycardia(VAsvt) and during pacing with same cycle length as tachycardia(VApace) were analysed in 48 patients to evaluate the usefullness in determining the mechanism of paroxysmal supraventricular tachycardia(PSVT) and the sites of accessory pathways. The results are as follows : 1)In differenciation AV nodal reentry from AV reentry mechanism, VAsvt(25.6+/-21.5 vs 148.0+/-27.7msec, p50msec(sensitivity 81%,specificity 100%) and VAsvt/VAace<0.7(sensitivity 71%, specificity 100%) suggested the high probability of left free wall accessory pathway. In Conclusion, VAsvt, VApace-VAsvt and VAsvt/VApace are useful parameters in determining the mechanism of PSVT and the sites of accessory pathways.