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
Abstract Management of symptomatic atrial tachycardia (AT) during pregnancy seems challenging, especially those originating from left atrial appendage (LAA), which easily tend to be incessant and mediate cardiomyopathy. It's contradictory between therapy and pregnancy. In this study, we report a case of a woman who presented with persistent AT, which lead to heart failure, during early pregnancy. She underwent successful catheter ablation using CartoSound and electroanatomic mapping without fluoroscopy. An electrophysiology (EP) study confirmed a focal LAA tachycardia. Soon after, left ventricular function of her heart normalized, and the patient successfully delivered a healthy child.
Subject(s)
Humans , Female , Pregnancy , Adult , Pregnancy Complications, Cardiovascular/surgery , Atrial Fibrillation/surgery , Catheter Ablation/methods , Atrial Appendage/surgery , Pregnancy Complications, Cardiovascular/diagnostic imaging , Atrial Fibrillation/diagnostic imaging , Atrial Appendage/diagnostic imaging , Electrocardiography , ElectrophysiologyABSTRACT
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
Introducción. La cardiomiopatía dilatada idiopática es la forma más común de cardiomiopatía en niños; sin embargo, ocasionalmente son identificadas causas potencialmente reversibles. Entre estas existe un grupo de pacientes con manifestaciones de insuficiencia cardiaca y taquicardia persistente que representan una forma de cardiomiopatía no familiar adquirida conocida como cardiomiopatía inducida por taquicardia o taquicardiomiopatía, que es reversible con el tratamiento efectivo de la taquicardia. Estos pacientes pueden ser mal diagnosticados y tratados de forma inapropiada. El diagnóstico frecuentemente es tardío, por lo que debe sospecharse en pacientes con insuficiencia cardiaca y taquicardia persistente sin causa aparente. Casos clínicos. Se describen seis casos de pacientes pediátricos de 6 a 16 años de edad (media 12 ± 4 años) que se presentaron con manifestaciones clínicas de insuficiencia cardiaca. Tuvieron seguimiento por una forma de cardiomiopatía dilatada en los que se documentaron diferentes mecanismos de taquiarritmia persistente como la causa. El tratamiento apropiado -mediante ablación con catéter- condujo a la recuperación de la función ventricular. Conclusiones. Es importante el reconocimiento de la cardiomiopatía inducida por taquiarritmia en pediatría. También es necesario un diagnóstico oportuno así como un tratamiento eficaz, ya que la cardiomiopatía inducida por taquicardia es una causa reversible de insuficiencia cardiaca.
Background. Idiopathic dilated cardiomyopathy is the most common form of cardiomyopathy in children; however, potentially reversible causes may occasionally be identified. Among these a group of patients with symptoms of congestive heart failure and persistent tachycardia representing a form of nonfamilial acquired cardiomyopathy known as tachycardia-induced cardiomyopathy or tachycardiomyopathy. This is a reversible condition with effective treatment of tachycardia. These patients may be misdiagnosed, potentially leading to inappropriate treatment. Diagnosis is often late and always should be suspected in patients with congestive heart failure and unexplained persistent tachycardia. Case reports. We describe six pediatric patients (mean age 12 ±4 years old, range 6-16 years). Patients presented with clinical manifestations of heart failure followed by dilated cardiomyopathy. Different mechanisms of persistent tachycardia were documented as the cause and total recovery was achieved of ventricular function after successful treatment of tachycardia by catheter ablation. Conclusions. The recognition of tachyarrhythmia-induced cardiomyopathy in pediatric patients is important. Opportune diagnosis and effective treatment are necessary because tachycardia-induced cardiomyopathy is a reversible cause of heart failure.
Subject(s)
Humans , Male , Middle Aged , Alcoholism/complications , Heart Failure/etiology , Autopsy , Fatal Outcome , Heart Failure/pathology , Hypothyroidism/complications , Myocardium/pathology , Obesity, Morbid/complications , Respiratory Insufficiency/etiology , Tachycardia/etiology , Tachycardia/pathologyABSTRACT
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.
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Objective To explore the mechanism of macro-reentry atrial tachycardia and to guide catheter ablation using electroanatomic mapping system in 3 patients.Methods Three patients(two females),aged 51?12 years,with atrial tachycardia were included.The mean history of symptom was 19?11 years.Conventional electrophysiological study was performed to determine the location of atrial tachycardia before the three dimensional geometry reconstruction.After voltage and activation maps were constructed,the mechanism of tachycardia was analyzed and the slow conduction areas(critical isthmus) were verified.Radiofrequency energy was delivered using irrigated-tip catheter.Results Though there was no evidence to suggest structural heart diseases,scar areas were found in the mapped atria in all the three cases.The mechanism of atrial tachycardia was found to be counter-clockwise macro-reentry around tricuspid valve,counter-clockwise macro-reentry around superior vena cava,and figure "8" reentry in left atria in the 3 patients respectively.The respective critical isthmus was found to be between the lateral scar and tricuspid valve,the lateral scar and superior vena cava,and two scars on the left atria roof.Ablation in the critical isthmus terminated all tachycardia.There were no atrial tachycardia recurrence during a follow-up of 9-10 months.Conclusion The substrate and electrophysiological mechanism of macro-reentry atrial tachycardia could be identified clearly,and navigation ablation could be performed effectively under the guidence of electroanatomic mapping.
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.