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.

Cardioneuroablation for severe neurocardiogenic syncope.

INTRODUCTION AND OBJECTIVES: Cardioneuroablation (CNA), a technique based on radiofrequency ablation of cardiac vagal ganglia, was developed to treat recurrent vasovagal syncope (VVS) with a predominant cardioinhibitory component, as an alternative to pacemaker implantation. The aim of our study was to evaluate the safety and success rate of CNA guided by extracardiac vagal stimulation in patients with highly symptomatic cardioinhibitory VVS. METHODS: Prospective study of patients who underwent anatomically guided CNA at two cardiology centers. All patients had a history of recurrent syncope with a predominant cardioinhibitory component and refractory to conventional measures. Acute success was determined by the absence or significant reduction of cardiac parasympathetic response to extracardiac vagal stimulation. The primary endpoint was the recurrence of syncope during follow-up. RESULTS: In total, 19 patients (13 males; mean age 37.8±12.9 years) were included. Ablation was acutely successful in all patients. One patient had a convulsive episode after the procedure, which was deemed unrelated to the ablation, requiring admission to intensive care but without sequelae. No other complications occurred. At a mean follow-up of 21.0±13.2 months (range 3-42 months), 17 patients remained free of syncope. The remaining two patients had recurrence of syncope and, despite undergoing a new ablation procedure, required pacemaker implantation during follow-up. CONCLUSION: Cardioneuroablation, confirmed by extracardiac vagal stimulation, appears to be an effective and safe treatment option for highly symptomatic patients with refractory VVS with a predominant cardioinhibitory component, providing a new potential approach as an alternative to pacemaker implantation.

Treatment of Symptomatic Functional Atrioventricular Block by Cardioneuroablation as an Alternative to Pacemaker Implantation.

A woman with recurrent presyncope caused by a functional atrioventricular (AV) block after meals, with limiting symptoms, underwent cardioneuroablation and AV node vagal denervation without pacemaker implantation. Normal AV conduction was recovered with complete abolishment of symptoms. (Level of Difficulty: Advanced.).

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.

Ablation of "Background Tachycardia" in Long Standing Atrial Fibrillation: Improving the Outcomes by Unmasking a Residual Atrial Fibrillation Perpetuator.

BACKGROUND: Catheter ablation of long-standing persistent AF (LSAF) remains challenging. Since AF-Nest (AFN) description, we have observed that a stable, protected, fast source firing, namely "Background Tachycardia"(BT), could be hidden beneath the chaotic AF. Following pulmonary vein isolation (PVI)+AFN ablation one or more BT may arise or be induced in 30-40% of patients, which could be the culprit forAF maintenance and ablation recurrences. METHODS AND RESULTS: We studied 114 patients, from 322 sequential LSAF regular ablations, having spontaneous or induced residual BT after EGM-guided PVI+AFN ablation of LSAF; 55.6±11y/o, 97males (85.1%), EF=65.5±8%, LA=42.8±6.7mm. Macroreentrant tachycardias were excluded. Pre-ablationAF 12-leads ECG Digital processing(DP) and spectral analysis(SA) was performed searching for BT before AF ablation and its correlation with BT during ablation.After PVI, 38.1±9 AFN sites/patient and 135 sustained BTs (1-3, 1.2±0.5/patient) were ablated. BT cycle length(CL) was 246.3±37.3ms. In 79 patients presenting suitable DP for SA, the BT-CL was 241.6±34.3ms with intra procedure BT-CL correlation r=0.83/p<0.01. Following BT ablation, AF could not be induced. During FU of 13→60 months(22.8±12m), AF freedom for BT RF(+) vs. BT RF(-) groups were 77.9% vs. 56.4% (p=0.009), respectively. There was no significant complication. CONCLUSION: BT ablation following PVI and AFN ablation improved long-term outcomes ofLSAF ablation. BT is likely due to sustained microreentry, protected during AF by entry block. BT can be suspected by spectral analysis of the pre-ablation ECG and is likely one important AF perpetuator by causing electrical resonance of the AFN. This ablation strategy warrants randomized, multicenter investigation.

Avanços, indicações e resultados do tratamento não-farmacológico da fibrilação atrial: ablação por cateter / Advances, indications and results of non-pharmacological atrial fibrillation treatment: catheter ablation

O surgimento de novos antiarritmicos e anticoagulantes e o grande avanço da ablação por radiofrequência na fibrilação atrial justificam a frequente revisao de conduta nessa que é a arrtmia sustentada mais frequente. Nos Estados Unidos, existem mais de 5 milhões de portadores, número que deverá triplicar até 2050. Ocorre em 10 por cento das pessoas com mais de 80 anos. Além dos sintomas, problemas hemodinâmicos e taquicardiomiopatia, essa arritmia acrescenta considerável risco de tromboembolismo. No Brasil, 26 por cento dos pacientes com mais de 80 anos que já tiveram acidente vascular cerebral isquêmico são portadores de fibrilação atrial. Mesmo na fibrilação atrial isolada, sem cardiopatia estrutural, o risco de tromboembolismo duplica e na fibrilação atrial da cardiopatia reumática o risco pode chegar a 17 vezes em relação à população normal. O tratamento com marca-passos ou com desfibriladores atriais não mostrou benefício ou aplicabilidade clínica. Nos últimos anos, novas drogas foram introduzidas; entretanto, o tratamento não-farmacológico, possibilidade de cura da fibrilação atrial e suspensão dos medicamentos, representa ao mesmo tempo o grande desafio e a grande aspiração da eletrofisiologia moderna. Nesse sentido, novos avanços no entendimento da fisiopatologia permitiram aumentar a taxa de sucesso da ablação por radiofrequência, tornando-a uma opção altamente atrativa e segura mesmo nos casos que, apesar de boa resposta, são altamente dependentes de medicação.

The development of new antiarrhythmic drugs and anticoagulants and the great advance of radiofrequency ablation in atrial fibrillation treatment justify a frequent review of the conduct against the most frequent types of sustained arrhythmia. In the USA there are over 5 million patients with atrial fibrillation, and this figure is likely to triple by 2050. It is observed in over 10% of people over 80 years of age. In addition to the symptoms, hemodynamic problems and tachycardiomyopathy, this arrhythmia has a considerable risk of thromboembolism. In Brazil, 26% of the patients over 80 years of age who have had a ischemic stroke have atrial fibrillation. Even in cases of atrial fibrillation alone, without structural heart disease, there is a 2-fold increase of the risk of thromboembolism and it may be up to 17 times higher than in the normal population in atrial fibrillation caused by rheumatic heart disease. The treatment with intelligent pacemakers or with atrial defibrillators has not shown any benefit or clinical applicability. In the last years new drugs have been introduced, however, non-pharmacological treatment with the possibility of curing atrial fibrillation and the discontinuation of drugs is a great challenge and the major hope of modern electrophysiology. New advances in the understanding of this pathophysiology have increased the success rate of radiofrequency ablation, making it an attractive and safe option in cases which, despite the good results, are highly dependent on medication.

Aspectos epidemiológicos da estimulação cardíaca no Brasil: 12º ano do RBM - Registro Brasileiro de Marcapassos, Desfibriladores e Ressincronizadores Cardíacos / Epidemiological aspects of Brazilian cardiac stimulation - 12th year of RBM - the Brazilian Pacemaker, Defibrillation and Resynchronization Registry / Aspectos epidemiológicos de la estimulación cardíaca en Brasil - 12º año del RBM - Registro Brasileño de Marcapasos, Desfibriladores y Resincronizadores Cardíacos

O Registro Brasileiro de Marcapassos, Desfibriladores e Ressincronizadores Cardíacos (RBM) é uma extensa base de dados nacional que dispõe de informações sobre os procedimentos de estimulação cardíaca em nosso país, tendo completado seu 12º ano em junho de 2006. No 12º observamos praticamente as mesmas tendências observadas nos anos anteriores: aumento da idade média dos pacientes, redução dos casos de doença de Chagas, maior implante de marcapassos atrioventriculares, entre outras. O número e procedimentos voltou a aumentar após uma redução observada no décimo ano do registro. Entretanto, o número de implantes de marcapassos por milhão de habitantes, ainda encontra-se muito aquém do observado em outros países.

The brazilian cardiac pacemaker, defibrillation and resynchronization registry (RBM) is an extensive national database that contains the information about cardiac stimulation procedures in Brazil, which reached its 12th year in June of 2006. During the 12th year we practically observed the same tendencies observed in previous years: an increase in patients average age, reduction in Chagas cases, greater number of atrioventricular pacemaker implants, among others. The number of procedures has increased after a reduction observed during the 10th year of registry. However, the number of pacemaker implants per million inhabitants, is still far from what is observed in other countries.

El Registro Brasileño de Marcapasos, Desfibriladores y Resincronizadores Cardíacos (RBM) es una extensa base de datos nacional que dispone de informaciones sobre los procedimientos de estimulación cardíaca en nuestro país, habiendo cumplido su 12º año en junio de 2006. En el 12º año, observamos prácticamente las mismas tendencias advertidas en los años anteriores: aumento de la edad media de los pacientes, reducción de los casos de enfermedad de Chagas, mayor implante de marcapasos atrioventriculares, entre otras. El número de procedimientos volvió a aumentar tras una reducción observada en el décimo año del registro. Sin embargo, el número de implantes de marcapasos por millón de habitantes todavía se halla muy lejos de lo advertido en otros países.