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 Outcome of Cardiac Denervation Procedures: The Anatomically Guided Septal Approach.

BACKGROUND: Functional bradycardia is a challenging condition that affects a healthy population. Ganglionated plexus ablation has emerged as a therapeutic alternative to avoid a pacemaker. OBJECTIVES: The purpose of this study is to evaluate long-term effects of anatomically guided cardiac denervation. METHODS: This is a prospective longitudinal study that included 36 patients with symptomatic functional bradycardia. Electroanatomic reconstruction of both atria was carried out, and the main septal ganglionated plexi were anatomically located and targeted. RESULTS: Ablation endpoints were: 1) heart rate increment; 2) Wenckebach cycle length shortening; and 3) atrio-Hisian (AH) interval shortening. A sinus node denervation was obtained in all patients with an increment of 21.6% in the mean heart rate. All patients presented a negative atropine test after ablation. Twenty-eight (77.7%) patients presented immediate sings of atrioventricular node denervation, with a shortening of 15.6% of mean Wenckebach cycle length and 15.9% of the mean AH interval. All heart rate variability parameters showed a significant reduction after 12 months, enduring after 18 months. Thirty (83.3%) patients remained free of events after a mean follow-up of 52.1 ± 35.2 months. One patient (2.77%) presented acute sinus node artery occlusion during ablation with persistent sinus dysfunction and had a pacemaker implantation; 3 (8.3%) other patients evolved with sinus tachycardia, and 4 (11.1%) patients presented syncope recurrence during follow-up, 3 (8.3%) of them requiring a pacemaker implantation. No other tachyarrhythmia was observed. CONCLUSIONS: The anatomically guided septal approach is an effective technique for syncope prevention, promoting long-lasting autonomic changes. No significant proarrhythmia effect has been observed during the long-term follow-up.

Cardioneuroablation: Where are we at?

Since its original description in 2005, catheter ablation techniques, commonly called cardioneuroablation, have emerged as a potential strategy for modulating autonomic function. Multiple investigators have provided observational data on the potential benefits of this technique in a variety of conditions associated with or exacerbated by increased vagal tone such as vasovagal syncope, functional atrioventricular block, and sinus node dysfunction. Patient selection, current techniques including the various mapping strategies, clinical experience, and limitations of cardioablation are reviewed. Finally, while cardioneuroablation has potential to be a treatment option for selected patients with symptoms mediated by hypervagotonia, the document outlines the important knowledge gaps that currently exist and the necessary next steps required before this technique can be widely implemented into clinical practice.

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.).

Initial Experience with Fractionation Mapping in the Identification of Vagal Ganglionated Plexus During Cardioneuroablation

This is a series case report of five symptomatic patients presented with diagnosis of sinus bradycardia, first and second degrees atrioventricular (AV) blocks, that were referred to pacemaker implantation. During the screening, a functional cause for the bradycardia and AV blocks were documented by treadmill stress test, 24-hour Holter monitoring and atropine test. After the confirmation of the diagnosis, patients were submitted to cardioneuroablation on an anatomical basis supported by a tridimensional electroanatomical fractionation mapping software. The technique and the acute and short-term results of the cardioneuroablation are described.

Cardioinhibitory syncope: from pathophysiology to treatment-should we think on cardioneuroablation?

Vasovagal syncope (VVS) is the most common type of syncope; the lone cardioinhibitory syncope represents only a small group of patients; however, the "cardioinhibitory component" is highly prevalent in reflex syncope and can be severe enough to produce asystole, lasting for a few seconds followed by a recovery to sinus beats. The environment in which syncope occurs can compromise life, and in-depth knowledge of the disease can prevent deaths and guide the appropriate management. The therapeutic cornerstone is general measures (increase water and salt) followed by pharmacologic therapy; for cardioinhibitory syncope, both treatments fail most of the time, and the next therapeutic option is pacemaker implantation. However, although the pacemaker causes a reduction in syncope, recurrence is high, and a one-time, effective, and safe intervention would be ideal. Cardioneuroablation (CNA) therapy has been proposed as a pacemaker alternative with these characteristics. CNA has shown a high reduction or even complete syncope elimination during 3 years of follow-up in some studies. Patients also reported prolonged prodromal periods, which allowed them enough time to abort the syncope. Invasive therapies like CNA require further extensive cohort studies, randomized clinical trials, and more substantial follow-up to evaluate adverse side effects. This review highlights syncope pathophysiology, dividing it into a central theory and a peripheral theory, the diagnosis explaining the head-up tilt test protocols, and treatments like CAN, representing it with figures for a simplified understanding.

Long-Term Follow-Up of Cardioneuroablation to Treat Second-Degree Block After Slow Pathway Ablation.

We present the long-term follow-up of a 31-year-old woman who underwent cardioneuroablation (for atrioventricular (AV) block. Slow pathway ablation was performed in September 2017 with normal follow-up until April 2018, when the patient started noticing symptoms of palpitations at rest, and the electrocardiogram showed a Mobitz I AV block. A cardiac stress test and 24-h Holter monitoring demonstrated first- and second-degree block and normal AV conduction during times of higher heart rate. (Level of Difficulty: Advanced.).

Selective atrial vagal denervation guided by spectral mapping to treat advanced atrioventricular block.

AIMS: Asymptomatic nocturnal long ventricular pauses are usually detected accidentally and it has been suggested that they may lead to sudden death. Identification of predisposing factors could prevent cardiovascular events. METHODS AND RESULTS: We report the case of a patient with frequent asymptomatic nocturnal ventricular pauses of 3-11 s, characteristic of a vagally mediated atrioventricular (AV) block. Echocardiography, treadmill test, thyroid function test levels, and polysomnogram were normal. In an attempt to reduce the risk, it was decided that an atrial vagal denervation induced by radiofrequency (RF) ablation (cardioneuroablation) could be useful. Spectral mapping was used to localize endocardial vagal innervation in the right and left aspects of the inter-atrial septum, responsible for the sinus node and AV node modulation, and RF pulses were applied in those sites only. After finishing the procedure, significant changes were observed in the heart rate (66-90 b.p.m.), atrial-His interval (115-74 ms), Wenckebach cycle length (820-570 ms), and sinus node recovery time (1100-760 ms). Follow-up Holter recording demonstrated that the number of ventricular pauses had reduced from 438 to 0. Heart rate and time domain characteristics were compatible with vagal denervation. CONCLUSION: Ablation of the endocardial vagal innervation sites seems to be safe and efficient in reducing the frequency and the length of the ventricular pauses. It was possible by identifying certain spectral components of the atrial electrogram, resulting in a conservative approach.