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.

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.

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.

Atualização das indicações de marcapasso e desfibriladores cardíacos / Up to date of pacemakers and implantable cardioverter defibrillators indications

As indicações de marcapasso têm sido bastante ampliadas nos últimos anos. No início da década de 60, os marcapassos eram utilizados somente para bloqueios atrioventriculares de 3ºgrau com síncope; porém, logo após o surgimento dos sistemas de demanda, passaram a ser utilizados em bloqueios menos graves e na doença do nó sinusal. Atualmente, os marcapassos, além das bradiarritmias, são empregados no tratamento das síndromes neuromediadas, da fibrilação atrial, da cardiomiopatia hipertrófica e da insuficiência cardíaca, da síndrome do QT longo, na incopetência cronotrópica, para controle em longo prazo de rejeição em transplante cardíaco, e até mesmo em casos muito peculiares de bloqueio atrioventricular de 1ºgrau.Os desfibriladores cardíacos que há alguns anos necessitavam que o paciente fosse recuperado de pelo menos dois episódios de morte súbita atualmente já são indicados mesmo no tratamento primário, ou seja, antes do primeiro episódio. Além disso, têm sido recomendados no tratamento da insuficiência cardíaca em associação com os ressincronizadores