Cardioneuroablation for Cardioinhibitory Vasovagal Syncope: Rationale, Approaches, and Its Role in Long-Term Management.

Purpose of Review: Cardioneuroablation (CNA) has emerged as a potential alternative to pacemaker therapy in well-selected cases with vasovagal syncope (VVS). In recent years, the number of CNA procedures performed by electrophysiologists has considerably risen. However, some important questions, including proper patient selection and long-term results, remain unanswered. The present article aims to critically review and interpret latest scientific evidence for clinical indications and how to approach long-term management. Recent Findings: CNA is a new approach that has been supported mainly by retrospective or observational data for its use in syncope. Overall, in mixed population studies treated with CNA, 83.3 to 100% have been reported to be free of syncope over follow-up periods of 6 to 52.1 months. For studies including patients who underwent CNA with pure VVS, 73.2 to 100% have been reported to be syncope-free over follow-up periods of 4 to 45.1 months. One large meta-analysis showed 91.9% freedom from syncope after CAN. To date, only one randomized controlled trial with small case number has been performed of CNA compared to non-pharmacological treatment in VVS. In this study of 48 patients with an average of 10 ± 9 spontaneous syncopal episodes prior to study enrollment and 3 ± 2 episodes in the year prior to CNA. After CNA, 92% were free of syncope compared with 46% treated with optimal non-pharmacological treatment to prevent new syncope episodes (P = 0.0004). To date, most studies have included younger patients (< 60 years of age). There are only limited data in patients older than 60, and some studies suggest less of an effect in relatively older patients. Summary: Cardioneuroablation can be performed to decrease syncope recurrence in adult patients aged < 60 years, with severe or recurrent cardioinhibitory syncope without prodromal symptoms, after proven failure of conventional therapies. Due to a paucity of data supporting efficacy in older individuals or for vasodepressor components, CNA in adult patients aged > 60 years or in the presence of a dominant vasodepressor should be considered investigational in severely symptomatic patients after proven failure of pharmacological and non-pharmacological therapies.

Cardioneuroablation for the management of patients with recurrent vasovagal syncope and symptomatic bradyarrhythmias: the CNA-FWRD Registry.

BACKGROUND: Cardioneuroablation has been emerging as a potential treatment alternative in appropriately selected patients with cardioinhibitory vasovagal syncope (VVS) and functional AV block (AVB). However the majority of available evidence has been derived from retrospective cohort studies performed by experienced operators. METHODS: The Cardioneuroablation for the Management of Patients with Recurrent Vasovagal Syncope and Symptomatic Bradyarrhythmias (CNA-FWRD) Registry is a multicenter prospective registry with cross-over design evaluating acute and long-term outcomes of VVS and AVB patients treated by conservative therapy and CNA. RESULTS: The study is a prospective observational registry with cross-over design for analysis of outcomes between a control group (i.e., behavioral and medical therapy only) and intervention group (Cardioneuroablation). Primary and secondary outcomes will only be assessed after enrollment in the registry. The follow-up period will be 3 years after enrollment. CONCLUSIONS: There remains a lack of prospective multicentered data for long-term outcomes comparing conservative therapy to radiofrequency CNA procedures particularly for key outcomes including recurrence of syncope, AV block, durable impact of disruption of the autonomic nervous system, and long-term complications after CNA. The CNA-FWRD registry has the potential to help fill this information gap.

Solving the Reach Problem: A Review of Present and Future Approaches for Addressing Ventricular Arrhythmias Arising from Deep Substrate.

Ventricular tachycardia (VT) is a significant cause of morbidity and mortality in patients with ischaemic and non-ischaemic cardiomyopathies. In most patients, the primary strategy of VT catheter ablation is based on the identification of critical components of reentry circuits and modification of abnormal substrate which can initiate reentry. Despite technological advancements in catheter design and improved ability to localise abnormal substrates, putative circuits and site of origins of ventricular arrhythmias (VAs), current technologies remain inadequate and durable success may be elusive when the critical substrate is deep or near to critical structures that are at risk of collateral damage. In this article, we review the available and potential future non-surgical investigational approaches for treatment of VAs and discuss the viability of these modalities.

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.

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.

Transient left bundle branch block associated with favipiravir treatment for coronavirus infection.

The coronavirus disease 2019 (COVID-19) may lead to a wide spectrum of clinical manifestations ranging from asymptomatic to symptomatic by having targets on various tissues such as lung parenchyma and myocardium (Shahrbaf et al., Cardiovasc Hematol Disord Drug Targets. 21(2):88-90, 2021). As an RNA-dependent RNApolymerase inhibitor, favipiravir has been proposed as a treatment in clinical studies done during the pandemic period (Furuta et al., Antiviral Res. 100(2):446-454, 2013). Although favipiravir is generally a safe medication, it may rarely cause cardiac adverse effects (Shahrbaf et al., Cardiovasc Hematol Disord Drug Targets. 21(2):88-90, 2021). To the best of our knowledge, favipiravir has not been reported to cause left bundle branch block (LBBB).

Non-fluoroscopic Cardioneuroablation for Deglutition-induced Syncope: Not a Bitter Pill to Swallow.

Swallowing is an uncommon trigger of reflex situational syncope. We discuss the case of a 61-year-old woman who presented without a prior cardiac history complaining of 15 years of dizzy spells and hot facial flushing provoked by the swallowing of solid foods.

Cardioneuroablation for treatment of carotid sinus syndrome secondary to oropharyngeal squamous cell cancer.

Head and neck tumors can rarely cause carotid sinus syndrome and this often resolves by surgical intervention or palliative chemoradiotherapy. If these modalities are not an option or are ineffective, the most preferred treatment is permanent pacemaker therapy. Here, we present the first case of cardioneuroablation treatment performed in patient with oropharyngeal squamous cell cancer who developed recurrent asystole and syncope attacks due to compression of the carotid sinus on neck movement.

Intrinsic Cardiac Neuromodulation in the Management of Atrial Fibrillation- A Potential Missing Link?

Atrial fibrillation (AF) is the most common supraventricular arrhythmia that is linked with higher cardiovascular morbidity and mortality. Recent evidence has demonstrated that catheter-based pulmonary vein isolation (PVI) is not only a viable alternative but may be superior to antiarrhythmic drug therapy for long-term freedom from symptomatic AF episodes, a reduction in the arrhythmia burden, and healthcare resource utilization with a similar risk of adverse events. The intrinsic cardiac autonomic nervous system (ANS) has a significant influence on the structural and electrical milieu, and imbalances in the ANS may contribute to the arrhythmogenesis of AF in some individuals. There is now increasing scientific and clinical interest in various aspects of neuromodulation of intrinsic cardiac ANS, including mapping techniques, ablation methods, and patient selection. In the present review, we aimed to summarize and critically appraise the currently available evidence for the neuromodulation of intrinsic cardiac ANS in AF.

Ganglionic Plexus Ablation: A Step-by-step Guide for Electrophysiologists and Review of Modalities for Neuromodulation for the Management of Atrial Fibrillation.

As the most common sustained arrhythmia, AF is a complex clinical entity which remains a difficult condition to durably treat in the majority of patients. Over the past few decades, the management of AF has focused mainly on pulmonary vein triggers for its initiation and perpetuation. It is well known that the autonomic nervous system (ANS) has a significant role in the milieu predisposing to the triggers, perpetuators and substrate for AF. Neuromodulation of ANS - ganglionated plexus ablation, vein of Marshall ethanol infusion, transcutaneous tragal stimulation, renal nerve denervation, stellate ganglion block and baroreceptor stimulation - constitute an emerging therapeutic approach for AF. The purpose of this review is to summarise and critically appraise the currently available evidence for neuromodulation modalities in AF.

Worldwide survey on implantation of and outcomes for conduction system pacing with His bundle and left bundle branch area pacing leads.

BACKGROUND: Adoption and outcomes for conduction system pacing (CSP), which includes His bundle pacing (HBP) or left bundle branch area pacing (LBBAP), in real-world settings are incompletely understood. We sought to describe real-world adoption of CSP lead implantation and subsequent outcomes. METHODS: We performed an online cross-sectional survey on the implantation and outcomes associated with CSP, between November 15, 2020, and February 15, 2021. We described survey responses and reported HBP and LBBAP outcomes for bradycardia pacing and cardiac resynchronization CRT indications, separately. RESULTS: The analysis cohort included 140 institutions, located on 5 continents, who contributed data to the worldwide survey on CSP. Of these, 127 institutions (90.7%) reported experience implanting CSP leads. CSP and overall device implantation volumes were reported by 84 institutions. In 2019, the median proportion of device implants with CSP, HBP, and/or LBBAP leads attempted were 4.4% (interquartile range [IQR], 1.9-12.5%; range, 0.4-100%), 3.3% (IQR, 1.3-7.1%; range, 0.2-87.0%), and 2.5% (IQR, 0.5-24.0%; range, 0.1-55.6%), respectively. For bradycardia pacing indications, HBP leads, as compared to LBBAP leads, had higher reported implant threshold (median [IQR]: 1.5 V [1.3-2.0 V] vs 0.8 V [0.6-1.0 V], p = 0.0008) and lower ventricular sensing (median [IQR]: 4.0 mV [3.0-5.0 mV] vs. 10.0 mV [7.0-12.0 mV], p < 0.0001). CONCLUSION: In conclusion, CSP lead implantation has been broadly adopted but has yet to become the default approach at most surveyed institutions. As the indications and data for CSP continue to evolve, strategies to educate and promote CSP lead implantation at institutions without CSP lead implantation experience would be necessary.