Long-term outcomes of cardioneuroablation with and without extra-cardiac vagal stimulation confirmation in severe cardioinhibitory neurocardiogenic syncope.

BACKGROUND: Cardioneuroablation (CNA) is a novel therapeutic approach for functional bradyarrhythmias, specifically neurocardiogenic syncope or atrial fibrillation, achieved through endocardial radiofrequency catheter ablation of vagal innervation, obviating the need for pacemaker implantation. Originating in the nineties, the first series of CNA procedures was published in 2005. Extra-cardiac vagal stimulation (ECVS) is employed as a direct method for stepwise denervation control during CNA. OBJECTIVE: This study aimed to compare the long-term follow-up outcomes of patients with severe cardioinhibitory syncope undergoing CNA with and without denervation confirmation via ECVS. METHOD: A cohort of 48 patients, predominantly female (56.3%), suffering from recurrent syncope (5.1 ± 2.5 episodes annually) that remained unresponsive to clinical and pharmacological interventions, underwent CNA, divided into two groups: ECVS and NoECVS, consisting of 34 and 14 cases, respectively. ECVS procedures were conducted with and without atrial pacing. RESULTS: Demographic characteristics, left atrial size, and ejection fraction displayed no statistically significant differences between the groups. Follow-up duration was comparable, with 29.1 ± 15 months for the ECVS group and 31.9 ± 20 months for the NoECVS group (p = .24). Notably, syncope recurrence was significantly lower in the ECVS group (two cases vs. four cases, Log Rank p = .04). Moreover, the Hazard ratio revealed a fivefold higher risk of syncope recurrence in the NoECVS group. CONCLUSION: This study demonstrates that concluding CNA with denervation confirmation via ECVS yields a higher success rate and a substantially reduced risk of syncope recurrence compared to procedures without ECVS confirmation.

Long-Term Evaluation of the Vagal Denervation by Cardioneuroablation using Holter and Heart Rate Variability

ABSTRACT: Several disorders present reflex or persistent increase in vagal tone that may cause refractory symptoms even in a normal heart patient. Cardioneuroablation (CNA), the vagal denervation by RF ablation of the neuromyocardial interface, was developed to treat these conditions without pacemaker implantation. A theoretical limitation could be the reinnervation, that naturally grows in the first year, that could recover the vagal hyperactivity. This study aims to verify the vagal denervation degree in the chronic phase after CNA. Additionally, it intends to investigate the arrhythmias behavior after CNA. METHODS - prospective longitudinal study with intra-patient comparison of 83 very symptomatic cases without significant cardiopathy, submitted to CNA, 49(59%) male, 47.3±17 years-old, having vagal paroxysmal atrial fibrillation 58(70%) or neurocardiogenic syncope 25(30%), NYHA Class < II and absence of significant comorbidities. CNA was performed in both atria by interatrial septum puncture, with irrigated conventional catheter and electroanatomic reconstruction. Ablation targeted the neuromiocardial interface by fragmentation mapping (AFNests) using the Velocity Fractionation software, conventional recording and anatomical localization of the ganglionated plexi. There were compared the time and frequency domain of the heart rate variability (HRV) and arrhythmias in 24h Holter pre-, 1-year-post- and 2-year-postCNA. Clinical outpatient follow-up and serial Holter showed 80% asymptomatic cases at 40 months. RESULTS - Time and frequency domain HRV demonstrated significant decrease in all autonomic parameters, showing an important parasympathetic and sympathetic activity reduction at 2 yearspost-CNA (p0.05) suggesting that the reinnervation has halted. There was also an important reduction in all brady- and tachyarrhythmias pre- vs. post-CNA, (p<0.01). CONCLUSIONS ­ There is an important and significant vagal and sympathetic denervation after 2 years of CAN with a significant reduction in brady and tachyarrhythmia in the whole group. There were no complications.

Long-Term Evaluation of the Vagal Denervation by Cardioneuroablation Using Holter and Heart Rate Variability.

BACKGROUND: Several disorders present reflex or persistent increase in vagal tone that may cause refractory symptoms even in a normal heart patient. Cardioneuroablation, the vagal denervation by radiofrequency ablation of the neuromyocardial interface, was developed to treat these conditions without pacemaker implantation. A theoretical limitation could be the reinnervation, that naturally grows in the first year, that could recover the vagal hyperactivity. This study aims to verify the vagal denervation degree in the chronic phase after cardioneuroablation. Additionally, it intends to investigate the arrhythmias behavior after cardioneuroablation. METHODS: Prospective longitudinal study with intrapatient comparison of 83 very symptomatic cases without significant cardiopathy, submitted to cardioneuroablation, 49 (59%) male, 47.3±17 years old, having vagal paroxysmal atrial fibrillation 58 (70%) or neurocardiogenic syncope 25 (30%), New York Heart Association class0.05) suggesting that the reinnervation has halted. There was also an important reduction in all bradyarrhythmias and tachyarrhythmias pre-cardioneuroablation versus post-cardioneuroablation (P<0.01). CONCLUSIONS: There is an important and significant vagal and sympathetic denervation after 2 years of cardioneuroablation with a significant reduction in bradyarrhythmia and tachyarrhythmia in the whole group. There were no complications.

Idiopathic VPC: Distribution Of FOCI And Tips Of Ablation.

Idiopathic Ventricular Premature Contraction (VPC) is currently more routinely referred for electrophysiology evaluation. Usually it carries a good prognosis but, when symptomatic or suspected to produce ventricular dysfunction, will require treatment. Nowadays, RF ablation has great advantages over antiarrhythmic drugs. Classically the outflow tract (right or left), with the typical inferior axis with left (eventually right) bundle brunch block like ECG morphology, is considered the most frequent site of origin for idiopathic VPC, but with the widespread of EP procedures and advancement of technology making possible to map and ablate difficult locations, it is possible to see a growing and changing population referred for idiopathic VPC ablation, displaying that, almost any region of the heart may be source of this kind of arrhythmia that can be successfully treated. A well-planned procedure, with the presumed region of origin settled and employing the current technology and knowledge (tips), will have a high chance of cure.

Simplified Method for Vagal Effect Evaluation in Cardiac Ablation and Electrophysiological Procedures.

OBJECTIVES: The aim of this study is to show a simplified reversible approach to investigate and confirm vagal denervation at any time during the ablation procedure without autonomic residual effect. BACKGROUND: Parasympathetic denervation has been increasingly applied in ablation procedures such as in vagal-related atrial fibrillation and cardioneuroablation. This method proposes an easy way to study the vagal effect and to confirm its elimination following parasympathetic denervation through vagal stimulation (VS) by an electrophysiological catheter placed in the internal jugular vein. METHODS: A prospective controlled study including 64 patients without significant cardiopathy (48 male [75.0%], age 46.4 ± 16.4 years) who had a well-defined RF ablation indication for symptomatic arrhythmias, comprising a "denervation group" (DG), with indication for ablation with parasympathetic denervation (vagal-related atrial fibrillation or severe cardioinhibitory syncope) and a "control group" (CG), with ablation indication without parasympathetic denervation (accessory pathway or ventricular arrhythmia). By using a neurostimulator, both groups underwent non simultaneous bilateral VS (8 to 12 s, frequency: 30 Hz, pulse width: 50 µs, amplitude: 0.5 to 1 V/kg up to 70 V) through the internal jugular vein pre- and post-ablation. RESULTS: Significant cardioinhibition was achieved pre-ablation in all cases (pause of 11.5 ± 1.9 s in DG vs. 11.4 ± 2.1 s in CG; p = 0.79). Eight patients (12.5%) presented catheter progression difficulty in 1 jugular vein (2 right, 6 left); however, the contralateral VS was adequate for cardioinhibition. After ablation, the cardioinhibition was reproduced only in CG (pause of 11.2 ± 2.2 s) as in DG it was entirely eliminated. There was no significant difference between pre- and post-ablation cardioinhibition in CG (p = 0.84). There was no complication (follow-up 8.8 ± 5 months). CONCLUSIONS: The vagal stimulation was feasible, easy, and reliable, and showed no complications. It may be repeated during the procedure to control the denervation degree without residual effect. It could be a suitable tool for vagal denervation confirmation or autonomic tests during electrophysiological studies. Ablation without parasympathetic denervation did not change the vagal response.

Ablación de la fibrilación auricular por catéter con radiofrecuencia guiada por mapeo espectral de los Nidos de FA en ritmo sinusal / Atrial fibrillation catheter RF-ablation guide

Usando el mapeo espectral endocárdio en ritmo sinusal nosotros podemos definir dos tipos de miocardio auricular: el fibrilar con espectro segmentado hacia la derecha - llamado Nido-FA (NFA) - y el compacto con espectro no segmentado hacia la izquierda. Al inducir FA nosotros hemos observado constantemente activación muy desorganizada sobre los Nidos-FA [tejido resonante reactivo] mientras el compacto mantiene una activación bien regular [ tejido pasivo]. Ambos son activados por una taquicardia protegida de alta frecuencia "Taquicardia de Background" (TB). Describir el tratamiento de la FA a través de la ablación - RF de los Nidos-FA y la TB. 92 p (76 H, 52,4 ± 11 a) con FA refractaria muy frecuente, 56 paroxístina, 25 persistente, 11 permanente sin cardiopatía significativa (AI 41, 9 ± 5mm). 1- Ablación- RF con catéter de los NFA [4/8 mm-60°/30-40J/30s] guiado por mapeo espectral en ritmo sinusal fuera de las venas pulmonares (VP); 2- Estimulación auricular (300 ppm); 3- Adicional ablación de los NFA cuando era inducida FA; 4- Ablación de TB focal o Flutter cuando eran inducidos; 4 - Seguimiento Clínico SC (EKG/Holter). Una media de 50 ± 18 nidos-FA / p fueron tratados. Después de SC 0 11,3 ± 8 meses 81p (88%) no tenía FA (28,3 % previamente utilizaban drogas AA no eficaces). Después de ablación los NFA: fue imposible reinducir FA en 61p (71 %); en 31p (29%) solo FA no sostenida (< 10s) fue inducida; TB fue inducida y tratada en 24p (26%). Dos derrames pericárdicos ocurrieron (tratada en 24p (26%). Dos derrames pericárdicos ocurrieron (tratada en 24p (26%). Dos derrames pericárdicos ocurrieron (tratados 1 clínicamente y 1 quirúrgicamente) descrito utilizando una específica y no más usada vaina. El mapeo espectral de los Nidos - FA fue fácil de hallar y ablacionar; Durante la FA los Nidos _ FA juegan un papel resonante reactivo mientras el compacto juega un papel pasivo, uno o ambos son activados por la TB de elevada frecuencia; Después de la ablación de los...

Using endocardial spectral mapping in sinus rhythm we found two kinds of atrial myocardium: fibrillar with a rightward - segmented spectrum - named AF - Nest (AFN) - and compact with a leftward non - segmented spectrum. Inducing AF we have consistently observed very highly disorganized activation only in the AF - Nest [reactive resonant tissue] while the compact myocardium maintains well - organized, predominantly regular activation [passive tissue]. Both are activated by a high frequency protected tachycardia "Background Tachycardia" (BT). To describe treatment of AF by AF - Nests and BT catheter RF - ablation. 92 (76 males, 52.4 ± 11 y) with very frequent refractory AF, paroxysmal in 56, persistent in 25, and permanent in 11 without any significant cardiopathy (LA 41. 9 ± 5mm). 1 - AFN Catheter RF ablation [4/8mm - 60°/30-40J/30s] guided by spectral mapping in sinus rhythm outside the pulmonary veins (PV); 2 - Atrial stimulation (300ppm); 3 - AFN additional ablation if AF induced; 4 - BT focal or flutter ablation if induced; 4 - Clinical FU (EKG/Holter). A mean of 50 ± 18 AF nests/person were treated. After 11. 3 ± 8 months of follow up, 81 (88%) patients had no AF (28. 3 % previously on no effective AA drugs). After AFN ablations, it Was not possible to reinduce AF in 61 (71%) cases. In 31 patients (29 %) only non - sustained AF (< 10s) was induced; BT was induced and treated in 24 patientns (26%). Two pericardial effusions occurred (1 clinically and 1 surgically treated) related to an isolated cause and the other to a sheath no longer in use. Using spectral mapping, AF - Nests were easily found and ablated. During AF - Nests play a reactive resonant role while the compact myocardium plays a passive one, both activated by the high frequency BT. After AF - nest and BT ablations it was not possible to reinduce sustained AF; AF - nest and BT ablation around the PV is safe, feasible and very efficient for the cure or control of AF.

Radiofrequency catheter ablation of atrial fibrillation guided by spectral mapping of atrial fibrillation nests in sinus rhythm.

BACKGROUND: Two types of myocardia can be observed through the endocardial spectral mapping (SM) in sinus rhythm: the compact type with a smooth spectrum and the fibrillar type with a segmented spectrum (atrial fibrillation nests). During the atrial fibrillation (AF), the compact type has an organized activation and low frequency (passive), whereas the fibrillar type has a rather disorganized activation and high frequency (active/resonant), with both being activated by high-frequency sustained tachycardia--the background tachycardia (BT). OBJECTIVE: To describe the treatment of AF by the ablation of the AF nests and BT. METHODS: 1) Catheter ablation of the AF nests with RF [4/8 mm-60 masculine/30-40 J/30s] guided by SM in sinus rhythm, outside the pulmonary vein; 2) atrial stimulation -300 ppm; 3) Additional ablation of the AF nests if AF is induced; 4) Focal ablation if BT and/or Flutter is induced; 5) Clinical follow-up+ ECG+ Holter. RESULTS: A total of 50+/-18 AF nests/patient were treated. After 11.3+/-8 m, 81 patients (88%) did not present AF (28.3% with antiarrhythmic drugs). After the ablation of the AF nests, AF was not reinduced in 61 patients (71%) and BT was induced and treated in 24 patients (26%). There were two episodes of pericardial bleeding (1 treated clinically and 1 surgically), caused by sheaths that are no longer used CONCLUSION: The SM in sinus rhythm can be used in the ablation of AF nests. During the AF, the AF nests present a reactive-resonant pattern and the compact myocardium is passive, stimulated by the high frequency of the BT. After the ablation of the AF nests and the BT, it was not possible to reinduce the sustained AF. The Ablation of AF nests outside the pulmonary veins showed to be safe and highly effective in the cure and/or clinical control of the AF.

Ablação da fibrilação atrial por cateter com radiofreqüência guiada por mapeamento espectral endocárdico dos "ninhos de FA" em ritmo sinusal / Radiofrequency catheter ablation of atrial fibrillation guided by spectral mapping of atrial fibrillation nests in sinus rhythm

FUNDAMENTO: Através de mapeamento espectral-(ME) endocárdico em ritmo sinusal, observam-se dois tipos de miocárdio atrial: o compacto de espectro liso e o fibrilar de espectro segmentado ("Ninho de FA" [NFA]). Durante a FA o compacto tem ativação organizada e baixa freqüência (passivo) enquanto o fibrilar apresenta ativação bastante desorganizada e alta freqüência (ativo/ressonante) sendo ambos ativados por uma taquicardia protegida de alta freqüência, taquicardia de background (TB). OBJETIVO: Descrever o tratamento da FA pela ablação dos NFA e da TB. MÉTODOS: 1) Ablação por cateter-RF [4/8mm-60°/30-40J/30s] dos NFA guiada por ME em ritmo sinusal, fora das veias pulmonares; 2) Estimulação atrial-300ppm; 3) Ablação adicional de NFA se induzida FA; 4) Ablação focal se induzida TB e/ou Flutter; 5) Seguimento clínico+ECG+Holter. RESULTADOS: Foram tratados 50±18 NFA/paciente. Após 11,3±8m 81p (88 por cento) estavam sem FA (28,3 por cento com antiarrítmico). Após a ablação dos NFA: a FA não foi reinduzida em 61p(71 por cento); TB foi induzida e tratada em 24p(26 por cento). Ocorreram 2 sangramentos pericárdicos (1 tratado clinicamente e 1 cirurgicamente) ocasionados por bainhas não mais utilizadas. CONCLUSÃO: O ME em ritmo sinusal ablaciona os NFA. Durante a FA os NFA apresentam um padrão reativo-ressonante e o miocárdio compacto apresenta-se passivo, estimulados pela alta freqüência da TB. Após a ablação dos NFA e da TB não foi possível reinduzir FA sustentada. A ablação dos NFA fora das VP se mostrou segura e altamente eficiente para a cura e/ou o controle clínico da FA.

BACKGROUND: Two types of myocardia can be observed through the endocardial spectral mapping (SM) in sinus rhythm: the compact type with a smooth spectrum and the fibrillar type with a segmented spectrum (atrial fibrillation nests). During the atrial fibrillation (AF), the compact type has an organized activation and low frequency (passive), whereas the fibrillar type has a rather disorganized activation and high frequency (active/resonant), with both being activated by high-frequency sustained tachycardia - the background tachycardia (BT). OBJECTIVE: To describe the treatment of AF by the ablation of the AF nests and BT. METHODS: 1) Catheter ablation of the AF nests with RF [4/8mm-60°/30-40J/30s] guided by SM in sinus rhythm, outside the pulmonary vein; 2) atrial stimulation -300ppm; 3) Additional ablation of the AF nests if AF is induced; 4) Focal ablation if BT and/or Flutter is induced; 5)Clinical follow-up+ ECG+ Holter. RESULTS: A total of 50±18 AF nests/patient were treated. After 11.3±8m, 81 patients (88 percent) did not present AF (28.3 percent with antiarrhythmic drugs). After the ablation of the AF nests, AF was not reinduced in 61 patients (71 percent) and BT was induced and treated in 24 patients (26 percent). There were two episodes of pericardial bleeding (1 treated clinically and 1 surgically), caused by sheaths that are no longer used CONCLUSION: The SM in sinus rhythm can be used in the ablation of AF nests. During the AF, the AF nests present a reactive-resonant pattern and the compact myocardium is passive, stimulated by the high frequency of the BT. After the ablation of the AF nests and the BT, it was not possible to reinduce the sustained AF. The Ablation of AF nests outside the pulmonary veins showed to be safe and highly effective in the cure and/or clinical control of the AF.

Arritmias na infância / Arrhthmias in childhood

Arritmias cardíacas de algum tipo ocorrem entre 10 por cento e 30 por cento nos exames de Holter nas crianças. Podem ser assintomáticas e benignas, porém em muitos casos produzem sintomas incapacitantes e risco de morte súbita. Frequentemente estão relacionadas a cardiopatias congênitas ou a cirurgias de correção, assim como à presença de feixes ou vias anômalas ou a cardiopatias adquiridas. A ablação por cateter por meio de radiofrequência mudou a história natural de muitas arritmias pediátricas, permitindo a cura definitiva na maioria dos casos. Adicionalmente, marcapassos especiais, desfibriladores e ressincronizadores estão cada vez mais estendendo seus benefícios ao pequeno paciente. Análises clínicas e laboratoriais...

Syncopal high-degree AV block treated with catheter RF ablation without pacemaker implantation.

A 23-year-old-female patient had undergone a very successful gastric banding surgery to treat obesity. Six months later she began to present recurrent syncope due to very frequent, intermittent high-degree AV block referred to as pacemaker implantation. The electrophysiological study showed impaired AV nodal conduction but the His-Purkinje conduction was preserved. Partial catheter radiofrequency ablation of the cardiac autonomic nervous system guided by spectral endocardial mapping (cardioneuroablation) was performed. The electrophysiological parameters were normalized. Holter recordings were normal and the patient was asymptomatic with normal life without pacemaker implantation in a follow-up 21 months later.

Syncopal high-degree AV block treated with catheter RF ablation without pacemaker implantation

A 23-year-old-female patient had undergone a very successful gastric banding surgery to treat obesity. Sixmonths later she began to present recurrent syncope due to very frequent, intermittent high-degree AV block referred to as pacemaker implantation. The electrophysiological study showed impaired AV nodalconduction but the His-Purkinje conduction was preserved. Partial catheter radiofrequency ablation of thecardiac autonomic nervous system guided by spectral endocardial mapping (cardioneuroablation) was performed. The electrophysiological parameters were normalized. Holter recordings were normal and the patient was asymptomatic with normal life without pacemaker implantation in a follow-up 21 months later.

"Cardioneuroablation"--new treatment for neurocardiogenic syncope, functional AV block and sinus dysfunction using catheter RF-ablation.

Cardiac neuroablation is a new technique for management of patients with dominantly adverse parasympathetic autonomic influence. The technique is based on radiofrequency (RF) ablation of autonomic connections in the three main ganglia around the heart. Their connections are identified by Fast-Fourier Transforms (FFTs) of endocardial signals: sites of autonomic nervous connections show fractionated signals with FFTs shifted to the right. In contrast, normal myocardium without these connections does not show these features. RF-ablation is thought to inflict permanent damage on the parasympathetic autonomic influence because its cells are adjacent to the heart whereas sympathetic cells are remote. Twenty-one patients with a mean age of 48 years, neurally mediated reflex syncope in six, functional high grade atrioventricular block in seven and sinus node dysfunction in 13 (there is overlap between the second and third groups) were treated. Follow-up for a mean of 9.2 months demonstrated success in all cases with relief of symptoms. No complications occurred.

A new treatment for atrial fibrillation based on spectral analysis to guide the catheter RF-ablation.

BACKGROUND: By studying the spectrum of atrial potentials by fast Fourier transform (FFT) we have found two types of atrial muscle: the compact (CM) and the fibrillar (FM) myocardium. The former presents normal in-phase conduction inferring a great number of cellular connections, long-lasting refractoriness and leftward FFT-shift. The latter shows anisotropic out-of-phase conduction, fewer cellular connections, short refractoriness and a segmented right-FFT-shift. The compact is the normal predominant muscle and the fibrillar is different and may be neural input, vein insertion, interatrial (1A) septum, left atrial (LA) roof, etc. or pathological tissue, being so by loss of cellular connections this is a possible mechanism for conversion of compact into fibrillar-like myocardium. During atrial fibrillation (AF), clusters of FM (AF nests) present higher frequencies than any surrounding tissue. PURPOSE: The purpose was to describe a new method for paroxysmal AF RF-ablation targeting AF nests. METHOD: Forty patients, six control and 34 having idiopathic drug-refractory paroxysmal or persistent AF were studied and treated. Two catheters were placed in the LA by transseptal approach. RF (30-40 J/60-70 degrees C) was applied to all sites outside the pulmonary veins (PV) presenting right-FFT-shift (AF nests). RESULTS: Numerous AF nests were found in 34/34 AF patients and only in 1/6 controls (only in this case it was possible to induce AF despite an absence of AF history). The main FM sites were: LA roof, LA septum, close to the insertion of the superior PV, near the insertion of the inferior PV, LA posterior wall, RA near the superior vena cava insertion, RA lateral and anterior wall and the right IA septum. Ablation of all AF nests near PV insertions resulted in 35 PV isolations. After 9.9 +/- 5 months only two AF patients presented relapse of a different AF form (coarse AF) which was very well controlled with medication previously ineffective. The AF was more frequent as the ratio FM/CM increased. CONCLUSIONS: The RF-ablation of AF nests decreasing the fibrillar/compact myocardium ratio eliminated 94% of the paroxysmal AF in patients in the FU of 9.9 +/- 5 months. The AF nests may be easily identified by spectral analysis and seem to be the real AF substrate. Paroxysmal AF may be cured or controlled by applying RF in several places outside the PV and, thereby, avoiding PV stenosis.