ABSTRACT
Resumo Fundamento Na fibrilação atrial paroxística (FAP), o isolamento das veias pulmonares com criobalão (IVP-CB) tem eficácia semelhante à da ablação por radiofrequência (IVP-RF). Em procedimentos de reablação após IVP-RF, a reconexão das VPs é alta, ao passo que em pacientes com reablação após IVP-CB, as informações são escassas. Objetivo Determinar os locais de reconexão das VPs em pacientes que foram submetidos à reablação após IVP-CB inicial. Métodos Pacientes que foram submetidos a um procedimento de reablação de fibrilação atrial, após um IVP-CB inicial para FAP foram incluídos. O mapeamento eletroanatômico do AE foi utilizado. Um local de reconexão foi definido com a presença de uma voltagem de 0,3mV ou maior nas VPs e condução unidirecional ou bidirecional nas VPs durante o ritmo sinusal. Os locais de reconexão foram identificados por meio de corte paraesternal longitudinal e posteriormente ablacionados com radiofrequência. Resultados Dos 165 pacientes submetidos ao IVP inicial, 27 necessitaram reablações, dos quais 18 (66,6%) eram do sexo masculino, com média de idade de 55+12,3 anos. O tempo de recorrência foi de 8,9+6,4 meses. A reconexão das VPs foi encontrada em 21 (77,8%) pacientes. Houve um total de 132 lacunas de condução, seis por paciente, 3,6 por VP. Um número significativo de lacunas ocorreu na região ântero-superior da VP superior esquerda (VPSE) e nas regiões septal e inferior da VP superior direita (VPSD). Conclusões As VPs superiores apresentaram os locais de maior reconexão, principalmente na região anterior da VPSE e na região septal da VPSD. A razão por trás disso pode ser devido à maior espessura da parede atrial e à dificuldade em alcançar o contato de criobalão adequado.
Abstract Background In paroxysmal atrial fibrillation (PAF), pulmonary vein isolation using cryoballoon (CB-PVI) has similar efficacy as radiofrequency ablation (RF-PVI) has. In redo ablation procedures following RF-PVI, PV reconnection is high, whereas in patients with redo following CB-PVI, information is scarce. Objective To determine the sites of PV reconnection in patients who underwent redo ablation after initial CB-PVI. Methods Patients who underwent an AF redo procedure, following an initial CB-PVI for PAF were included. LA electroanatomic mapping was used. A reconnection site was defined as the presence of a voltage of 0.3mV or greater in the PV and unidirectional or bidirectional conduction in the PV during sinus rhythm. Reconnections sites were identified using a clock-face view description and were ablated with radiofrequency afterwards. Results Out of the 165 patients who underwent initial PVI, 27 required redo ablations, of which 18 (66.6%) were males, with a mean age of 55+12.3 years. The time of recurrence was 8.9+6.4 months. PV reconnection was found in 21 (77.8%) patients. There was a total of 132 conduction gaps, six per patient, 3.6 per PV. A significant number of gaps were in the anterosuperior region of the left superior PV (LSPV), and in the septal and inferior regions of the right superior PV (RSPV). Conclusions The upper PVs had the most reconnection sites, mostly at the anterior region of the LSPV and the septal region of the RSPV. The reason behind this may be due to greater atrial wall thickness, and difficulty in achieving adequate cryoballoon contact.
Subject(s)
Humans , Male , Adult , Aged , Pulmonary Veins/surgery , Atrial Fibrillation/surgery , Catheter Ablation , Cryosurgery , Recurrence , Treatment Outcome , Middle AgedABSTRACT
The characteristic of atypical atrial flutter episodes on electrocardiogram is different from the typical atrial flutter.Due to the poor diagnosis awareness about atypical atrial flutter,which is easily misdiagnosed as other arrhythmia,for example sinus arrhythmia,atrial fibrillation,and Ⅲ °atrioventricular block.Here we reported a case of atypical atrial flutter in child.In addition to the characteristics of typical atrial flutter,such as regular and more fixed atrial rhythm,fluctuated ventricular rate,faster atrial rate than the ventricular rate,the patient was found equipotential line,slow atrial rate,and uprighted F wave on the inferior wall leads and V 1 lead of electrocardiogram,which were different from typical atrial flutter.
ABSTRACT
Objective To investigate the mechanisms of right atrial tachycardia(AT) occurring after atriotomy of structural heart disease under the guidance of image integration system(CartoMerge system) and explore the efficacy of catheter ablation by using the aboved technique.Methods From January 2005 to December 2006,forty consecutive drug-refractory patients presenting with AT underwent complete electroanatomic mapping of spontaneously occurring and inducible right ATs.The ablation strategy was to avoid visible anatomic anomaly under the guidance of image integration system and to transect the isthmus,usually targeting the narrowest portion of the isthmus.Patients were followed up on an outpatient basis with clinical evaluation and 24-hour Holter recordings being performed at three months,six months,and afterwards on a yearly basis.Results Three main tachycardia mechanisms were identified: single-loop macroreentrant atrial tachycardia(MAT)(n=36),double-loop MAT(n=16),and focal AT(n=4).In most MATs,critical isthmus areas were identified most frequently the cavotricuspid isthmus(CTI)(n=35) and the surgical incision isthmus(n=36).Surgical incision causing obvious morphological anomalies including scar-like anomaly,pouch-like anomaly,and node-like anomaly could be visible by image integration technique in 12 patients,which had the electrophysiological characteristics of a surgical incision(a CDP or scar).A mean number of 19.5?10.1 radiofrequency(RF) applications were delivered to terminate the circuit.During a follow-up of 18?10 months the RF ablation was acutely successful in all patients.Eight patients(20%) had an early recurrence of MAT and needed an additional ablation procedure.Conclusion Image integration system not only allows reconstruction of AT mechanisms,but also represents an advance in the accurate localization and ablation of the arrhythmogenic substrate of postsurgical AT.Three-dimensional MR/CT images of RA can be successfully extracted and registered to anatomically guide catheter ablation in RA.The display of real and detailed anatomic information during the procedure enables tailored RF ablation to individual distorted anatomy related with surgical incision.
ABSTRACT
Objective To investigate electrophysiologic characteristics,the original site of atrial tachycardia(AT)and the results of radiofrequency catheter ablation(RFCA)in children without structural heart disease.Methods Electrophysiologic study and RFCA were performed in 46 children with AT.The site of origin of AT was mapped by using activation mapping during tachycardia.Magnetic electroanatomical mapping(CARTO system)for ablation of atrial tachycardia was performed in 4 patients.Preselecting a temperature of 50~60 ℃ was selected for ablation.Results Electrophysiologic study verified that the mechanism of all the tachycardias in 46 children was focal AT,which might be short paroxysmal,paroxysmal or persistent.1 child also had atrioventricular nodal reentrant tachycardia.ATs were successfully ablated in 41 children(89%),in which 39 had one original site(27 foci in right atrium and 12 foci in left atrium),2 had at least two original sites.Conclusion The success rate of RFCA in ATs of children without structural heart disease was relatively high.Atrial taclycardia could be eliminated by radiofrequency current with safety and efficacy.