RESUMEN
PURPOSE: Radiofrequency (RF) catheter ablation of the slow pathway (SP) in atrioventricular nodal reentry tachycardia (AVNRT) is highly effective; however, it may require prolonged fluoroscopy and RF time. We postulated that visualization of the SP region with intracardiac echocardiography (ICE) could decrease ablation time, minimize radiation exposure, and facilitate SP ablation compared to the standard, fluoroscopy-guided approach. METHODS: In our study, we randomized 91 patients undergoing electrophysiologic study and SP ablation for AVNRT into 2 groups: fluoroscopy-only (n = 48) or ICE-guided (n = 43) group. Crossover to ICE-guidance was allowed after 8 unsuccessful RF applications. RESULTS: Mapping plus ablation time (mean ± standard deviation: 18.8 ± 16.1 min vs 11.6 ± 15.0 min, p = 0.031), fluoroscopy time (median [interquartile range]: 4.9 [2.93-8.13] min vs. 1.8 [1.2-2.8] min, p < 0.001), and total ablation time (144 [104-196] s vs. 81 [60-159] s, p = 0.001) were significantly shorter in the ICE group. ICE-guidance was associated with reduced radiation exposure (13.2 [8.2-13.4] mGy vs. 3.7 [1.5-5.8] mGy, p < 0.001). The sum of delivered RF energy (3866 [2786-5656] Ws vs. 2283 [1694-4284] Ws, p = 0.002) and number of RF applications (8 [4.25-12.75] vs. 4 [2-7], p = 0.001) were also lower with ICE-guidance. Twelve (25%) patients crossed over to the ICE-guided group. All were treated successfully thereafter with similar number, time, and cumulative energy of RF applications compared to the ICE group. No recurrence occurred during the follow-up. CONCLUSIONS: ICE-guidance during SP ablation significantly reduces mapping and ablation time, radiation exposure, and RF delivery in comparison to fluoroscopy-only procedures. Moreover, early switching to ICE-guided ablation seems to be an optimal choice in challenging cases.
Asunto(s)
Ablación por Catéter , Taquicardia por Reentrada en el Nodo Atrioventricular , Ablación por Catéter/métodos , Ecocardiografía , Técnicas Electrofisiológicas Cardíacas , Fluoroscopía/métodos , Humanos , Taquicardia por Reentrada en el Nodo Atrioventricular/diagnóstico por imagen , Taquicardia por Reentrada en el Nodo Atrioventricular/etiología , Taquicardia por Reentrada en el Nodo Atrioventricular/cirugía , Resultado del TratamientoRESUMEN
BACKGROUND: Right atrial (RA) dual-loop reentrant tachycardia has been described in patients who have undergone open heart surgery. However, the prevalence, electrophysiological (EP) substrate, and ablation outcomes have been poorly characterized. OBJECTIVE: The purpose of this study was to investigate the prevalence, EP substrate, and ablation outcomes for RA dual-loop reentrant tachycardia after cardiac surgery. METHODS: We identified all patients with atrial tachycardia (AT) after cardiac surgery. We compared EP findings and outcomes of those with RA dual-loop reentrant tachycardia to a control group of patients with RA macroreentrant arrhythmias in the setting of linear RA free-wall (FW) scar. RESULTS: Of the 127 patients with 152 postsurgical ATs, 28 of the ATs (18.4%) had RA dual-loop reentry and 24 of 28 (85.7%) had tricuspid annular reentry combined with FW incisional reentry. An incision length >51.5 mm along the FW predicted the substrate for a second loop. In 22 of 23 patients (95.7%) with initial ablation in the cavotricuspid isthmus, a change in the interval between Halod to CSp could be recorded, and 15 of 23 patients (65.2%) had coronary sinus activation pattern change. Complete success was achieved in 25 of 28 patients (89.3%) in the dual-loop reentry group and in 64 of 69 patients (92.8%) in the control group. After mean follow-up of 33.9 ± 24.2 months, 24 of 28 patients (85.7%) and 60 of 69 patients (86.95%) were free of arrhythmias after the initial procedure in the 2 groups, respectively. CONCLUSION: The prevalence of RA dual-loop reentry is 18.4% of ATs with prior atriotomy scar. A long incision should alert physicians to the possibility of a second loop at the FW. Halo and coronary sinus activation patterns provide important clues to circuit transformation.
Asunto(s)
Procedimientos Quirúrgicos Cardíacos/efectos adversos , Ablación por Catéter/métodos , Técnicas Electrofisiológicas Cardíacas/métodos , Sistema de Conducción Cardíaco/fisiopatología , Complicaciones Posoperatorias , Taquicardia por Reentrada en el Nodo Atrioventricular/epidemiología , Adulto , China/epidemiología , Femenino , Sistema de Conducción Cardíaco/cirugía , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Taquicardia por Reentrada en el Nodo Atrioventricular/etiología , Taquicardia por Reentrada en el Nodo Atrioventricular/cirugía , Resultado del TratamientoAsunto(s)
Fascículo Atrioventricular Accesorio , Potenciales de Acción , Frecuencia Cardíaca , Taquicardia por Reentrada en el Nodo Atrioventricular/etiología , Taquicardia Supraventricular/etiología , Estimulación Cardíaca Artificial , Ablación por Catéter , Diagnóstico Diferencial , Electrocardiografía , Técnicas Electrofisiológicas Cardíacas , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Taquicardia por Reentrada en el Nodo Atrioventricular/diagnóstico , Taquicardia por Reentrada en el Nodo Atrioventricular/fisiopatología , Taquicardia por Reentrada en el Nodo Atrioventricular/cirugía , Taquicardia Supraventricular/diagnóstico , Taquicardia Supraventricular/fisiopatología , Taquicardia Supraventricular/cirugía , Factores de Tiempo , Resultado del TratamientoAsunto(s)
Bloqueo de Rama/etiología , Taquicardia por Reentrada en el Nodo Atrioventricular/etiología , Taquicardia Paroxística/etiología , Potenciales de Acción , Adulto , Bloqueo de Rama/diagnóstico , Bloqueo de Rama/fisiopatología , Estimulación Cardíaca Artificial , Electrocardiografía , Técnicas Electrofisiológicas Cardíacas , Frecuencia Cardíaca , Humanos , Masculino , Taquicardia por Reentrada en el Nodo Atrioventricular/diagnóstico , Taquicardia por Reentrada en el Nodo Atrioventricular/fisiopatología , Taquicardia Paroxística/diagnóstico , Taquicardia Paroxística/fisiopatología , Factores de TiempoRESUMEN
Background: Intra-atrial re-entrant tachycardia (IART) is a frequent and severe complication in patients with congenital heart disease (CHD). Cavotricuspid isthmus (CTI)-related IART is the most frequent mechanism. However, due to fibrosis and surgical scars, non-CTI-related IART is also frequent. Objective: The main objective of this study was to describe the types of IART and circuit locations and to define a cut-off value for unhealthy tissue in the atria. Methods and results: This observational study included all consecutive patients with CHD who underwent a first ablation procedure for IART from January 2009 to December 2015 (94 patients, 39.4% female, age: 36.55 ± 14.9 years, 40.4% with highly complex cardiac disease). During the study, 114 IARTs were ablated (1.21 ± 0.41 IARTs per patient). Cavotricuspid isthmus-related IART was the only arrhythmia in 51% (n = 48) of patients, non-CTI-related IART was the only mechanism in 27.7% (n = 26), and 21.3% of patients (n = 20) presented both types of IART. In cases of non-CTI-related IART, the most frequent location of IART isthmus was the lateral or posterolateral wall of the venous atria, and a voltage cut-off value for unhealthy tissue in the atria of 0.5 mV identified 95.4% of IART isthmus locations. Conclusion: In our population with a high proportion of complex CHD, CTI-related IART was the most frequent mechanism, although non-CTI-related IART was present in 49% of patients (alone or with concomitant CTI-related IART). A cut-off voltage of 0.5 mV could identify 95.4% of the substrates in non-CTI-related IART.
Asunto(s)
Función Atrial , Atrios Cardíacos/fisiopatología , Sistema de Conducción Cardíaco/fisiopatología , Cardiopatías Congénitas/complicaciones , Taquicardia por Reentrada en el Nodo Atrioventricular/etiología , Potenciales de Acción , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Ablación por Catéter , Niño , Preescolar , Técnicas Electrofisiológicas Cardíacas , Femenino , Atrios Cardíacos/cirugía , Sistema de Conducción Cardíaco/cirugía , Cardiopatías Congénitas/diagnóstico , Cardiopatías Congénitas/fisiopatología , Frecuencia Cardíaca , Humanos , Masculino , Persona de Mediana Edad , Taquicardia por Reentrada en el Nodo Atrioventricular/diagnóstico , Taquicardia por Reentrada en el Nodo Atrioventricular/fisiopatología , Taquicardia por Reentrada en el Nodo Atrioventricular/cirugía , Adulto JovenRESUMEN
Most tachycardias in the pulmonary venous atrium are inaccessible by direct means and require either a retrograde approach or a transseptal approach for ablation. We present a case in which successful radiofrequency ablation of common atrioventricular nodal reentrant tachycardia was accomplished via a retrograde transaortic approach guided by nonfluoroscopic mapping with use of the NavX™ mapping system. The patient was a 49-year-old woman who at the age of 4 years had undergone Mustard repair for complete dextrotransposition of the great arteries. Three-dimensional reconstructions of the ascending aorta, right ventricle, systemic venous atrium, left ventricle, and superior vena cava-inferior vena cava baffle complex were created, and the left-sided His bundle was marked. After a failed attempt at ablation from the systemic venous side, we eliminated the atrioventricular nodal reentrant tachycardia by ablation from the pulmonary venous side. This case is, to our knowledge, the first report of successful radiofrequency ablation of common atrioventricular nodal reentrant tachycardia after Mustard repair for this congenital cardiac malformation in which ablation was guided by 3-dimensional nonfluoroscopic imaging. This imaging technique enabled accurate anatomic location of the ablation catheters in relation to the His bundle marked from the systemic venous side.
Asunto(s)
Operación de Switch Arterial/efectos adversos , Ablación por Catéter , Técnicas Electrofisiológicas Cardíacas , Venas Pulmonares/cirugía , Taquicardia por Reentrada en el Nodo Atrioventricular/cirugía , Transposición de los Grandes Vasos/cirugía , Potenciales de Acción , Electrocardiografía , Femenino , Frecuencia Cardíaca , Humanos , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Venas Pulmonares/fisiopatología , Taquicardia por Reentrada en el Nodo Atrioventricular/diagnóstico , Taquicardia por Reentrada en el Nodo Atrioventricular/etiología , Taquicardia por Reentrada en el Nodo Atrioventricular/fisiopatología , Transposición de los Grandes Vasos/diagnóstico , Resultado del TratamientoAsunto(s)
Fibrilación Atrial/terapia , Cardioversión Eléctrica/efectos adversos , Frecuencia Cardíaca , Taquicardia por Reentrada en el Nodo Atrioventricular/etiología , Taquicardia Supraventricular/terapia , Potenciales de Acción , Fibrilación Atrial/diagnóstico , Fibrilación Atrial/fisiopatología , Estimulación Cardíaca Artificial , Ablación por Catéter , Electrocardiografía , Técnicas Electrofisiológicas Cardíacas , Femenino , Humanos , Persona de Mediana Edad , Taquicardia por Reentrada en el Nodo Atrioventricular/diagnóstico , Taquicardia por Reentrada en el Nodo Atrioventricular/fisiopatología , Taquicardia por Reentrada en el Nodo Atrioventricular/cirugía , Taquicardia Supraventricular/diagnóstico , Taquicardia Supraventricular/fisiopatologíaRESUMEN
Supraventricular arrhythmias are a frequent complication in adults with congenital heart disease (ACHD). The prevalence increases with time since surgery, complexity of the underlying defect, type of repair and older age at surgery. Arrhythmias are the most frequent reason for hospital admission and along with heart failure the leading cause of death. The arrhythmia-associated increase in morbidity and mortality makes their management a key task in patients with ACHD. Intra-atrial re-entry is the most frequent arrhythmia mechanism. Less common arrhythmia mechanisms are supraventricular tachycardias in the presence of an accessory pathway, atrioventricular nodal re-entrant tachycardia or focal tachycardias. Patient management includes stroke prevention, acute termination and prevention of arrhythmia recurrence. Acute treatment depends on patients' symptoms. In cases of haemodynamic instability, immediate cardioversion is warranted. For stable patients, acute treatment includes rate control and termination by antiarrhythmic drugs or electrical cardioversion. Following a symptomatic arrhythmia, catheter ablation or treatment with antiarrhythmic drugs is recommended to prevent recurrences. Advances in mapping and ablation technology are now associated with high success rates of catheter ablation. In patients with a complex substrate recurrence rates of 50% remain high. However, in the presence of side effects and complications associated with long-term antiarrhythmic drug therapy, redo procedures are encouraged by current guidelines.
Asunto(s)
Antiarrítmicos/uso terapéutico , Ablación por Catéter , Cardiopatías Congénitas/complicaciones , Taquicardia por Reentrada en el Nodo Atrioventricular/terapia , Taquicardia Supraventricular/terapia , Fascículo Atrioventricular Accesorio/fisiopatología , Adulto , Factores de Edad , Antiarrítmicos/efectos adversos , Ablación por Catéter/efectos adversos , Ablación por Catéter/mortalidad , Electrocardiografía , Técnicas Electrofisiológicas Cardíacas , Sistema de Conducción Cardíaco/fisiopatología , Cardiopatías Congénitas/mortalidad , Cardiopatías Congénitas/cirugía , Humanos , Recurrencia , Factores de Riesgo , Accidente Cerebrovascular/etiología , Accidente Cerebrovascular/prevención & control , Taquicardia por Reentrada en el Nodo Atrioventricular/etiología , Taquicardia por Reentrada en el Nodo Atrioventricular/mortalidad , Taquicardia por Reentrada en el Nodo Atrioventricular/fisiopatología , Taquicardia Supraventricular/etiología , Taquicardia Supraventricular/mortalidad , Taquicardia Supraventricular/fisiopatología , Factores de Tiempo , Resultado del TratamientoRESUMEN
BACKGROUND: Variability in atrioventricular (AV) node location in congenital heart disease (CHD) can make catheter ablation for atrioventricular nodal reentrant tachycardia (AVNRT) challenging. OBJECTIVE: The purpose of this study was to describe institutional technique and outcomes for slow pathway modification in a cohort with CHD. METHODS: The study consisted of a retrospective review of CHD patients who underwent study from 2001 to 2013 with a diagnosis of AVNRT. Outcomes for slow pathway modification were recorded. In cases in which ablation was deferred, the reasons for this choice were examined. RESULTS: Forty-nine patients (median age 19 years) were included. CHD anatomy involved d-transposition of the great arteries (n = 6), "congenitally corrected" transposition of the great arteries (n = 4), Ebstein anomaly (n = 4), tetralogy of Fallot (n = 5), venous anomalies (n = 8), single ventricle (n = 16), and miscellaneous (n = 6). Ablation was attempted in 39 patients, using radiofrequency energy in 24, cryoablation in 8, and both in 7. Acute success rate was 92% (36/39). One patient had first-degree block in response to cryoablation, but no other complications occurred. At median follow-up 32 months, 1 patient had AVNRT recurrence. Most of the 10 patients in whom ablation was deferred had single-ventricle anatomy with uncertain AV node location. CONCLUSION: Ablation for AVNRT in CHD can be accomplished successfully with attention to underlying anatomy and prior surgery. Patients with single ventricle are a difficult subgroup, and a pharmacologic approach may be indicated in some cases if node localization is ambiguous.
Asunto(s)
Nodo Atrioventricular , Cardiopatías Congénitas , Taquicardia por Reentrada en el Nodo Atrioventricular , Adolescente , Adulto , Nodo Atrioventricular/patología , Nodo Atrioventricular/fisiopatología , Ablación por Catéter/métodos , Preescolar , Electrocardiografía/métodos , Técnicas Electrofisiológicas Cardíacas/métodos , Femenino , Estudios de Seguimiento , Sistema de Conducción Cardíaco/patología , Sistema de Conducción Cardíaco/fisiopatología , Cardiopatías Congénitas/complicaciones , Cardiopatías Congénitas/diagnóstico , Cardiopatías Congénitas/fisiopatología , Humanos , Masculino , Massachusetts , Persona de Mediana Edad , Evaluación de Resultado en la Atención de Salud , Recurrencia , Taquicardia por Reentrada en el Nodo Atrioventricular/diagnóstico , Taquicardia por Reentrada en el Nodo Atrioventricular/etiología , Taquicardia por Reentrada en el Nodo Atrioventricular/cirugía , Factores de TiempoRESUMEN
Owing to increased life expectancy, patients with grown-up congenital heart disease nowadays present various types of arrhythmias. We report treatment of a 27-year-old patient with tricuspid and pulmonary atresia who was referred to our department with symptomatic tachycardia. During electrophysiologic study, a diagnosis of typical AV-nodal re-entrant tachycardia was made, and he was successfully treated despite the described anatomic malformation.
Asunto(s)
Nodo Atrioventricular/fisiopatología , Ablación por Catéter/métodos , Sistema de Conducción Cardíaco/cirugía , Taquicardia por Reentrada en el Nodo Atrioventricular/cirugía , Atresia Tricúspide/complicaciones , Adulto , Electrocardiografía , Técnicas Electrofisiológicas Cardíacas , Estudios de Seguimiento , Sistema de Conducción Cardíaco/fisiopatología , Humanos , Masculino , Taquicardia por Reentrada en el Nodo Atrioventricular/etiología , Taquicardia por Reentrada en el Nodo Atrioventricular/fisiopatología , Atresia Tricúspide/fisiopatología , Atresia Tricúspide/cirugíaRESUMEN
AIMS: The aim of the study was to describe the complex electrophysiological features of accessory pathways (APs) in adult Ebstein's anomaly (EA). METHODS AND RESULTS: We performed a retrospective study of 17 consecutive adult EA cases with APs who underwent electrophysiological study and radiofrequency catheter ablation (RFCA) from November 2011 to May 2013. There were a total of 24 atrioventricular reentrant tachycardias (AVRTs) due to 23 APs, including 20 (87.0%) non-decremental conducting, 2 (8.7%) decremental conducting, and 1 (4.3%) nodofascicular bundle. Six (6/17 = 35.3%) patients had two APs while others had only one. Twenty-one APs (91.3%) in 15 patients were manifested and 2 APs (8.7%) in 2 patients were concealed. Six APs (26.1%) were broad, while 17 APs (73.9%) were narrow in width. Two patients suffered from duodromic tachycardias mediated by two APs. Accessory pathways were mainly located on the posterior, posteroseptal, and posterolateral tricuspid annulus (TA). Right ventriculography confirmed that all APs were located on the anatomic TA. All the patients remained free from tachycardias during 11.9 ± 6.8 months of follow-up after RFCA. For the 15 patients with manifest APs, 10 patients' electrocardiograms (ECGs) after RFCA demonstrated morphologies of right bundle branch block, while 5 patients' ECGs were normal. CONCLUSIONS: Accessory pathways in EA are predominantly right-sided, manifest and localize to the lower half of the anatomic TA. A number of APs in EA have broad widths. The incidence of multiple APs is high in these patients and RFCA is effective.
Asunto(s)
Fascículo Atrioventricular Accesorio/fisiopatología , Anomalía de Ebstein/complicaciones , Taquicardia por Reentrada en el Nodo Atrioventricular/etiología , Fascículo Atrioventricular Accesorio/cirugía , Adolescente , Adulto , Ablación por Catéter , China , Anomalía de Ebstein/diagnóstico , Anomalía de Ebstein/fisiopatología , Electrocardiografía , Técnicas Electrofisiológicas Cardíacas , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Taquicardia por Reentrada en el Nodo Atrioventricular/diagnóstico , Taquicardia por Reentrada en el Nodo Atrioventricular/fisiopatología , Taquicardia por Reentrada en el Nodo Atrioventricular/cirugía , Factores de Tiempo , Resultado del Tratamiento , Adulto JovenRESUMEN
BACKGROUND: We sought to investigate the feasibility of radiofrequency catheter ablation of atrioventricular node reentrant tachycardia and the ideal site for slow pathway (SP) ablation in congenitally corrected transposition of the great arteries. METHODS AND RESULTS: Nine patients with congenitally corrected transposition of the great arteries referred for catheter ablation of atrioventricular node reentrant tachycardia were studied. A single His potential was recorded in 8 patients (89%, 6 {S,L,L} and 2 {I,D,D}). The earliest atrial activation during retrograde atrioventricular node conduction occurred at His bundle region (HBE; n=7) or shifting from HBE to coronary sinus ostium (n=1, {S,L,L}). Two anatomically separate His potentials were recorded in 1 patient (11%, {S,L,L}), one at the anteroseptum (HBE-1) and the other at the confluence of the pulmonary and mitral annulus (HBE-2). In 8 cases with a single His potential recorded, SP was abated at the posterior-midseptum, 2 ({S,L,L}) at the right posteroseptum, 1 ({S,L,L}) at the left posteroseptum, and 5 (3 {S,L,L} and 2 {I,D,D}) at the midseptum after failure of energy application at the posteroseptum. Junctional rhythm was observed during radiofrequency catheter ablation in all 8 of the cases. In the remaining patient with 2 anatomically separate His potentials recorded, SP was successfully ablated from the confluence of the pulmonary and mitral annulus, slightly below the HBE-2. Junctional rhythm was also induced during radiofrequency catheter ablation. CONCLUSIONS: In {S,L,L} or {I,D,D}, radiofrequency catheter ablation of atrioventricular node reentrant tachycardia is feasible. SP input region can mainly be found in the posterior midseptum, especially in patients with single penetrating atrioventricular nodes. SP could usually be successfully ablated in these regions.
Asunto(s)
Ablación por Catéter/métodos , Taquicardia por Reentrada en el Nodo Atrioventricular/etiología , Taquicardia por Reentrada en el Nodo Atrioventricular/cirugía , Transposición de los Grandes Vasos/complicaciones , Potenciales de Acción/fisiología , Adolescente , Adulto , Transposición Congénitamente Corregida de las Grandes Arterias , Electrocardiografía , Técnicas Electrofisiológicas Cardíacas , Estudios de Factibilidad , Femenino , Estudios de Seguimiento , Sistema de Conducción Cardíaco , Humanos , Masculino , Persona de Mediana Edad , Taquicardia por Reentrada en el Nodo Atrioventricular/fisiopatología , Adulto JovenAsunto(s)
Aorta/patología , Aneurisma de la Aorta/complicaciones , Cardiopatías/etiología , Válvula Tricúspide/patología , Anciano , Aneurisma de la Aorta/diagnóstico , Ablación por Catéter , Dilatación Patológica , Técnicas Electrofisiológicas Cardíacas , Femenino , Atrios Cardíacos/diagnóstico por imagen , Atrios Cardíacos/patología , Cardiopatías/diagnóstico , Humanos , Cifosis/complicaciones , Tomografía Computarizada Multidetector , Taquicardia por Reentrada en el Nodo Atrioventricular/diagnóstico , Taquicardia por Reentrada en el Nodo Atrioventricular/etiología , Taquicardia por Reentrada en el Nodo Atrioventricular/cirugía , Válvula Tricúspide/diagnóstico por imagenRESUMEN
We descrive a patient who presents palpitations during cardiac rehabilitation after mitral valvuloplasty. ECG showed regular narrow QRS tachycardia compatible with Atrioventricular Node Reentrant Tachycardia. After slow pathway radiofrequency catheter ablation, the patient completed the rehabilitation program remained tachycardia and palpitations-free.
Asunto(s)
Valvuloplastia con Balón , Taquicardia por Reentrada en el Nodo Atrioventricular/etiología , Adulto , Ablación por Catéter , Electrocardiografía , Técnicas Electrofisiológicas Cardíacas , Humanos , Válvula Mitral , Taquicardia por Reentrada en el Nodo Atrioventricular/diagnósticoRESUMEN
BACKGROUND: Differentiating atypical atrioventricular nodal reentrant tachycardia (AVNRT) from septal orthodromic reentrant tachycardia (ORT(Septal)) is challenging in nonsustained tachycardia. When sustained, the postpacing interval minus tachycardia cycle length following entrainment (PPI(Entrainment) - TCL) and stimulation to atrial interval minus ventriculoatrial interval (Stim-A(Entrainment) - VA) are utilized. OBJECTIVE: We hypothesized that the first tachycardia cycle after tachycardia induction with right ventricular apical extrastimulation would yield comparable information to entrainment, precluding the need for sustained tachycardia. METHODS: Twenty-four patients with AVNRT (age 47 ± 18 years), 19 with ORT(Septal) (age 42 ± 17 years), and 15 with ORT over a left lateral accessory pathway (ORT(Left)) (age 41 ± 16 years) were included. The ventricular extrastimulus to atrial depolarization at tachycardia initiation (Stim-A(Initiation)) and tachycardia VA interval were measured to establish the Stim-A(Initiation) minus VA interval (Stim-A(Initiation) - VA). The ventricular extrastimulus to the subsequent right ventricular apical depolarization (postpacing interval at initiation, PPI(Initiation)) was utilized to obtain the PPI(Initiation) minus TCL (PPI(Initiation) - TCL). The AH interval associated with the PPI(Initiation) minus the AH in tachycardia was utilized to establish a corrected PPI(Initiation) minus TCL (cPPI(Initiation) - TCL). RESULTS: The intervals after tachycardia initiation were longer for AVNRT than for ORT: mean PPI(Initiation) - TCL (193 ± 44 vs 91 ± 73; P <.001), cPPI(Initiation) - TCL (174 ± 44 ms vs 88 ± 50 ms; P <.001), and Stim-A(Initiation) - VA (161 ± 45 ms vs 69 ± 53 ms; P <.001). The correlation coefficient for Stim-A(Initiation) minus VA against Stim-A(Entrainment) minus VA was 0.79 and for cPPI(Initiation) minus TCL against PPI(Entrainment) minus TCL was 0.71. cPPI(Initiation) minus TCL <115 ms or Stim-A(Initiation) - VA <85 ms was observed only in ORT. The converse was observed in AVNRT but also in ORT(Septal) over decremental accessory pathways and ORT(Left). CONCLUSION: Stim-A(Initiation) - VA < 85 ms or cPPI(Initiation) - TCL < 115 ms excludes AVNRT.
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Fascículo Atrioventricular Accesorio , Técnicas Electrofisiológicas Cardíacas/métodos , Sistema de Conducción Cardíaco/fisiopatología , Tabiques Cardíacos/fisiopatología , Taquicardia por Reentrada en el Nodo Atrioventricular , Fascículo Atrioventricular Accesorio/complicaciones , Fascículo Atrioventricular Accesorio/diagnóstico , Fascículo Atrioventricular Accesorio/fisiopatología , Adulto , Anciano , Diagnóstico Diferencial , Estimulación Eléctrica/métodos , Electrocardiografía/métodos , Femenino , Frecuencia Cardíaca , Humanos , Masculino , Persona de Mediana Edad , Taquicardia por Reentrada en el Nodo Atrioventricular/diagnóstico , Taquicardia por Reentrada en el Nodo Atrioventricular/etiología , Taquicardia por Reentrada en el Nodo Atrioventricular/fisiopatologíaRESUMEN
AIM: In some patients with clinical paroxysmal supraventricular tachycardia (PSVT), who are candidates for radiofrequency (RF) catheter ablation, attempts for the induction of arrhythmia during the electrophysiological study (EPS) fail despite different stimulation protocols even during the isoproterenol infusion and atropine injection. The presence of an atrial-His interval (AH) jump during decremental pre-mature atrial stimulation is the only clue for slow pathway ablation in these patients; in occasional patients, however, the AH jump is an accidental finding and the real arrhythmia is not atrioventricularnodal reentrant tachycardia (AVNRT). We aimed to introduce a new method for the induction of AVNRT in these patients. METHODS AND RESULTS: Ten patients (50% male, mean age=44.40 ± 12.80 years) with clinical PSVT who were referred to our department for the EPS and RF catheter ablation were selected. These patients had documented clinical PSVT with non-inducible arrhythmia during the EPS with different stimulation protocols even during the isoproterenol infusion and atropine injection but they only showed an AH jump. To induce AVNRT, low-watt (15-20), low-temperature (40-45°C) RF currents were delivered into the slow pathway area for a maximum of 40 s. Atrioventricularnodal reentrant tachycardia was inducible in five cases (50%, three male, mean age=45.80 ± 9.65 years). Induction of AVNRT occurred either during the RF current application after the occurrence of junctional ectopic beats or after another stimulation protocol. CONCLUSION: A low-watt, low-temperature RF current application into the slow pathway area can be a provocative method for the induction of AVNRT probably by AV-junction warming and conduction-velocity augmentation.
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Tratamiento de Radiofrecuencia Pulsada/métodos , Taquicardia por Reentrada en el Nodo Atrioventricular/etiología , Taquicardia por Reentrada en el Nodo Atrioventricular/fisiopatología , Taquicardia Paroxística/fisiopatología , Taquicardia Ventricular/fisiopatología , Adulto , Atropina/efectos adversos , Atropina/farmacología , Ablación por Catéter , Técnicas Electrofisiológicas Cardíacas , Femenino , Estudios de Seguimiento , Sistema de Conducción Cardíaco/efectos de los fármacos , Humanos , Isoproterenol/efectos adversos , Isoproterenol/farmacología , Masculino , Persona de Mediana Edad , Taquicardia por Reentrada en el Nodo Atrioventricular/inducido químicamente , Taquicardia Paroxística/cirugía , Taquicardia Ventricular/cirugía , TemperaturaRESUMEN
The ablation of atrioventricular (AV) nodal reentrant tachycardia in patients with the Senning or Mustard procedure is quite challenging because these atrial baffle procedures isolate the AV node from systemic venous access. Cryoablation is commonly utilized for AV nodal slow pathway modification in patients with structurally normal hearts. The cryoablation technique offers the advantage of monitoring AV nodal conduction during lesions, with the ability to terminate a lesion prior to permanent injury to the AV node. This case describes the successful cryoablation of the slow AV nodal pathway via the transbaffle approach in a patient with d-transposition of the great arteries status post the Mustard procedure.
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Procedimientos Quirúrgicos Cardíacos/efectos adversos , Criocirugía , Taquicardia por Reentrada en el Nodo Atrioventricular/cirugía , Transposición de los Grandes Vasos/cirugía , Adulto , Cineangiografía , Técnicas Electrofisiológicas Cardíacas , Femenino , Humanos , Taquicardia por Reentrada en el Nodo Atrioventricular/diagnóstico , Taquicardia por Reentrada en el Nodo Atrioventricular/etiología , Resultado del TratamientoRESUMEN
UNLABELLED: Slowed atrial conduction may contribute to reentry circuits and vulnerability for atrial fibrillation (AF). The autonomic nervous system (ANS) has modulating effects on electrophysiological properties. However, complex interactions of the ANS with the arrhythmogenic substrate make it difficult to understand the mechanisms underlying induction and maintenance of AF. AIM: To determine the effect of acute ANS modulation in atrial activation times in patients (P) with paroxysmal AF (PAF). METHODS AND RESULTS: 16P (9 men; 59±14years) with PAF, who underwent electrophysiological study before AF ablation, and 15P (7 men; 58±11years) with atrioventricular nodal reentry tachycardia, without documentation or induction of AF (control group). Each group included 7P with arterial hypertension but without underlying structural heart disease. The study was performed while off drugs. Multipolar catheters were placed at the high right atrium (HRA), right atrial appendage (RAA), coronary sinus (CS) and His bundle area (His). At baseline and with HRA pacing (600ms, shortest propagated S2) we measured: i) intra-atrial conduction time (IACT, between RAA and atrial deflection in the distal His), ii) inter-atrial conduction time (interACT, between RAA and distal CS), iii) left atrial activation time (LAAT, between atrial deflection in the distal His and distal CS), iv) bipolar electrogram duration at four atrial sites (RAA, His, proximal and distal CS). In the PAF group, measurements were also determined during handgrip and carotid sinus massage (CSM), and after pharmacological blockade of the ANS (ANSB). AF was induced by HRA programmed stimulation in 56% (self-limited - 6; sustained - 3), 68.8% (self-limited - 6; sustained - 5), and 50% (self-limited - 5; sustained - 3) of the P, in basal, during ANS maneuvers, and after ANSB, respectively (p=NS). IACT, interACT and LAAT significantly lengthened during HRA pacing in both groups (600ms, S2). P with PAF have longer IACT (p<0.05), a higher increase in both IACT, interACT (p<0.01) and electrograms duration (p<0.05) with S2, and more fragmented activity, compared with the control group. Atrial conduction times and electrograms duration were not significantly changed during ANS stimulation. Nevertheless, ANS maneuvers increased heterogeneity of the local electrograms duration. Also, P with sustained AF showed longer interACT and LAAT during CSM. CONCLUSION: Atrial conduction times, electrograms duration and fractionated activity are increased in PAF, suggesting a role for conduction delays in the arrhythmogenic substrate. Acute vagal stimulation is associated with prolonged interACT and LAAT in P with inducible sustained AF and ANS modulation may influence the heterogeneity of atrial electrograms duration.
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Fibrilación Atrial/fisiopatología , Sistema Nervioso Autónomo/fisiología , Técnicas Electrofisiológicas Cardíacas , Sistema de Conducción Cardíaco/fisiopatología , Taquicardia por Reentrada en el Nodo Atrioventricular/fisiopatología , Enfermedad Aguda , Anciano , Fibrilación Atrial/etiología , Fibrilación Atrial/cirugía , Ablación por Catéter , Femenino , Atrios Cardíacos/inervación , Atrios Cardíacos/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Tiempo de Reacción/fisiología , Taquicardia por Reentrada en el Nodo Atrioventricular/etiología , Taquicardia por Reentrada en el Nodo Atrioventricular/cirugíaRESUMEN
AIMS: To study anterograde atrioventricular (A-V) nodal electrophysiological properties through the right-atrial (Ri) and left-atrial inputs (Li) under the pharmacological autonomic blockade (AUB) in patients with slow-fast A-V nodal re-entrant tachycardia (AVNRT) and in controls. METHODS AND RESULTS: Twenty-nine patients with slow-fast AVNRT and 15 control subjects were included. Programmed stimulation with single extrastimulus was performed from the right atrial appendage to test the Ri, and from the posterolateral coronary sinus to test the Li. The AUB was induced with intravenous atropine (0.04 mg/kg) and metoprolol (0.15 mg/kg). The A-V nodal conduction times, refractoriness, discontinuous conduction (≥ 40 ms atrial-His interval 'jump'), and inducibility of AVNRT or reciprocating beats were compared. The A-V nodal conduction times were longer: (i) through the Ri than Li, (ii) in patients than controls, and (iii) in baseline than after AUB--at slow rates in both groups and at fast rates in patients through the right input only (P < 0.05-0.001). A significantly longer slow pathway effective refractory period was demonstrated through the Li than the Ri in patients in baseline (P < 0.05). The discontinuous conduction was demonstrated 94 times in 25 of 29 (83%) patients and 15 times in 6 of 15 (40%) controls (P < 0.01), and was most frequently encountered with the Ri testing. Likewise, inducibility was manifested most frequently with the Ri testing (P = 0.08), and decreased after AUB during this testing only (P = 0.05). CONCLUSION: The inherent magnitude of discordance of A-V nodal conduction velocity, refractoriness, and parasympathetic modulation between the Ri and Li to the A-V node may play a role in the aetiology of AVNRT.
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Nodo Atrioventricular/fisiopatología , Fenómenos Electrofisiológicos/fisiología , Atrios Cardíacos/fisiopatología , Taquicardia por Reentrada en el Nodo Atrioventricular/fisiopatología , Adulto , Antiarrítmicos/farmacología , Atropina/farmacología , Sistema Nervioso Autónomo/efectos de los fármacos , Sistema Nervioso Autónomo/fisiopatología , Fascículo Atrioventricular/fisiopatología , Estudios de Casos y Controles , Técnicas Electrofisiológicas Cardíacas , Femenino , Humanos , Masculino , Metoprolol/farmacología , Persona de Mediana Edad , Taquicardia por Reentrada en el Nodo Atrioventricular/etiologíaRESUMEN
Anatomic displacement of the atrioventricular node and associated conduction tissue in atrioventricular septal defects has been previously described. In spite of the increasing use of cryothermal catheter ablation in the pediatric population, there remains very little literature regarding its use in congenital heart disease. We describe successful cryothermal modification of the slow atrioventricular nodal pathway in a 12-year-old patient with a previously repaired partial atrioventricular septal defect and inducible atrioventricular nodal reentrant tachycardia. The use of a steerable catheter to locate the displaced His signal combined with the use of cryothermal energy allowed for the safe and effective treatment of this patient's tachycardia.