ABSTRACT
Abstract Background: Idiopathic ventricular tachycardia (VT) in children with structurally normal hearts is generally unrelated to the risk of sudden arrhythmic death. Still, it may be associated with deterioration in the quality of life. VT involving the fascicular conduction system is the most typical form of idiopathic left VT. In this retrospective study, we describe the experience of the clinical presentation, catheter ablation, and long-term follow-up of left fascicular VT in children. Methods: An electrophysiological study was performed on consecutive children at a single tertiary center. Clinical fascicular left VT was induced by programmed stimulation, and catheter ablation was guided searching for Purkinje potentials. Results: We included 18 patients (0.8 patients/year): 14 (77.8%) males and four females. The mean age of the first VT episode was 8.5 ± 5 years. Intravenous verapamil administration was effective for paroxysmal fascicular VT but not for prevention of recurrences. The mean age at the time of catheter ablation was 11.1 ± 3.8 years (8 months-16 years). The mean weight was 36.8 ± 16.4 kg (8.7-58 kg). A 100% success rate was observed with catheter ablation after repeated procedures without major complications. Mean follow-up was 2.0 ± 1.2 years (1.0-4.0 years, median 1.5), with permanent success in all patients and no antiarrhythmic drug administration. Conclusions: Fascicular VT has an adverse clinical course in children. In most cases, this condition is drug refractory. Catheter ablation is successful and safe treatment and should represent the first-line approach in symptomatic children.
Resumen Introducción: La taquicardia ventricular (TV) idiopática en niños con corazón estructuralmente normal generalmente no se relaciona con el riesgo de muerte súbita arrítmica, pero puede asociarse con deterioro de la calidad de vida. La TV que involucra el sistema de conducción fascicular es la forma más común de TV izquierda idiopática. En este estudio retrospectivo se describe la experiencia de presentación clínica, ablación con catéter y seguimiento a largo plazo de TV fascicular en niños. Métodos: Se llevó a cabo un estudio electrofisiológico en niños consecutivos en un centro terciario. La TV fascicular clínica se indujo mediante la estimulación programada y la ablación con catéter fue guiada buscando el registro de potenciales de Purkinje. Resultados: Se incluyeron 18 pacientes (0.8 pacientes/año): 14 (77.8%) de sexo masculino y cuatro de sexo femenino. La media de edad a la cual ocurrió el primer episodio fue de 8.5 ± 5 años. La administración intravenosa de verapamilo fue eficaz para la TV fascicular paroxística, pero no para prevención de recurrencias. La media de edad de la ablación con catéter fue de 11.1 ± 3.8 años (8 meses-16 años). La media del peso fue 36.8 ± 16.4 kg (8.7-58 kg). Se observó el 100% de éxito con la ablación con catéter después de procedimientos repetidos sin complicaciones mayores. La media de seguimiento fue de 2.0 ± 1.2 años (1.0-4.0, mediana de 1.5 años) con éxito permanente en todos los pacientes y sin administración de fármacos antiarrítmicos. Conclusiones: En niños, el curso clínico de la TV fascicular es adverso. Además, en la mayoría de los casos, esta condición es refractaria a fármacos. La ablación con catéter resulta exitosa y segura y debe representar el abordaje de primera línea en niños sintomáticos.
ABSTRACT
This is a series case report of five symptomatic patients presented with diagnosis of sinus bradycardia, first and second degrees atrioventricular (AV) blocks, that were referred to pacemaker implantation. During the screening, a functional cause for the bradycardia and AV blocks were documented by treadmill stress test, 24-hour Holter monitoring and atropine test. After the confirmation of the diagnosis, patients were submitted to cardioneuroablation on an anatomical basis supported by a tridimensional electroanatomical fractionation mapping software. The technique and the acute and short-term results of the cardioneuroablation are described.
Subject(s)
Syncope , Bradycardia , Atrioventricular BlockABSTRACT
Objective@#To evaluate the efficacy and safety of three-dimensional electroanatomical mapping system for catheter ablation of paroxysmal supraventricular tachycardiain (PSVT) children.@*Methods@#Clinical data from 187 children with paroxysmal supraventricular tachycardia undergoing radiofrequency catheter ablation in our department between January 2012 and April 2016 were analyzed. Among the patients, 91 cases were treated with traditional two-dimensional X-ray radiofrequency ablation, 96 cases were treated with radiofrequency ablation guided by three-dimensional electroanatomical mapping system. Postoperative electrocardiogram and echocardiography follow-up was performed at 1, 3, 6, 12, and 24 months. The success rate, recurrence rate, complication rate, operation time and amount of X-ray exposure were compared between the two groups. Kaplan-Meier survival curve was used to analyze the PSVT-free survival rate of the patients between the 2 groups.@*Results@#The mean follow-up time was (739±92) days. The success rate (95.8%(92/96) vs. 94.5%(86/91), P=0.912), recurrence rate (5.4%(5/92) vs. 4.7%(4/86), P=0.807), complication rate (4.2%(4/96) vs. 5.5%(5/91), P=0.379), operation time ((73±31)min vs. (79±36)min, P=0.124) were similar between the two groups. However, X-ray exposure time ((8.1±2.9)min vs. (21.3±8.4)min, P=0.026), amount of X-ray ((23±11)mGy vs. (58±23)mGy, P=0.013) were significantly lower in the three-dimensional electroanatomical mapping system group than in the traditional two-dimensional X-ray radio frequency ablation group. PSVT-free survival rate was similar between the two groups (χ2=0.060, P=0.807) .@*Conclusion@#Three-dimensional electroanatomical mapping system is safe and effective for radiofrequency ablation of paroxysmal supraventricular tachycardia in children, and can significantly reduce the amount of radiation as compared to the traditional two-dimensional X-ray radiofrequency ablation.
ABSTRACT
BACKGROUND AND OBJECTIVES: Identifying the critical isthmus of slow conduction is crucial for successful treatment of scar-related ventricular tachycardia. Current 3D mapping is not designed for tracking the critical isthmus and may lead to a risk of extensive ablation. We edited the algorithm to track the delayed potential in order to visualize the isthmus and compared the edited map with a conventional map. SUBJECTS AND METHODS: We marked every point that showed delayed potential with blue color. After substrate mapping, we edited to reset the annotation from true ventricular potential to delayed potential and then changed the window of interest from the conventional zone (early, 50-60%; late, 40-50% from peak of QRS) to the edited zone (early, 80-90%; late, 10-20%) for every blue point. Finally, we compared the propagation maps before and after editing. RESULTS: We analyzed five scar-related ventricular tachycardia cases. In the propagation maps, the resetting map showed the critical isthmus and entrance and exit sites of tachycardia that showed figure 8 reentry. However, conventional maps only showed the earliest ventricular activation sites and searched for focal tachycardia. All of the tachycardia cases were terminated by ablating the area around the isthmus. CONCLUSION: Identifying the channel and direction of the critical isthmus by a new editing method to track delayed potential is essential in scar-related tachycardia.
Subject(s)
Tachycardia , Tachycardia, VentricularABSTRACT
Objective To explore the feasibility and effectiveness of 3D electroanatomical navigation system(CARTO3)-guided catheter ablation for idiopathic right ventricular outflow tract premature ventricular contractions(RVOT-PVCs). Methods A total of 49 consecutive patients with RVOT-PVCs undergoing catheter ablation were divided into two groups: 3D group received CARTO3-guided ablation (n=29) and the conventional group received X-Ray-guided ablation (n=20). The operation time, X-ray fluoroscopy time, X-ray fluoroscopy exposure, cost, complication, successfully rates and recurrence rates were compared between the two groups. Results The immediate success rates were 100% (29/29) in the 3D group and 95% (19/20) in the conventional group. Complications were found in 3 cases in the conventional group and not found in the 3D group. Fluoroscopy time of 3D group was significantly shorter than that of the X-Ray group([1.3±3.6] min vs [44.2±28.2] min, P<0.01), and the radiation dose was also significantly lower than that of the X-Ray group ([93±242] mGy vs [3 919±2 309] mGy, P<0.01), but the 3D group had significantly higher cost compared with the X-Ray group (P<0.01). There was no significant difference in the total operation time lengths between the two groups. Twenty(69.0%) of the 29 cases in the 3D group avoided fluoroscopy entirely. Conclusion Our study indicates that CARTO 3 system is safe and effective in guiding ablation for patients with RVOT-PVCs; the method can greatly reduce fluoroscopy time and fluoroscopy dose, and in many cases non-fluoroscopic radiofrequency catheter ablation(RFCA)can be achieved.