Cardioneuroablation for the treatment of reflex syncope and functional bradyarrhythmias. A Scientific Statement of the European Heart Rhythm Association (EHRA) of the ESC, the Heart Rhythm Society (HRS), the Asia Pacific Heart Rhythm Society (APHRS) and the Latin American Heart Rhythm Society (LAHRS).

Cardioneuroablation has emerged as a potential alternative to cardiac pacing in selected cases with vasovagal reflex syncope, extrinsic vagally induced sinus bradycardia-arrest or atrioventricular block. The technique was first introduced decades ago, and its use has risen over the past decade. However, as with any intervention, proper patient selection and technique are a prerequisite for a safe and effective use of cardioneuroablation therapy. This document aims to review and interpret available scientific evidence and provide a summary position on the topic.

Discontinuation of cardiac implantable electronic device therapy after transvenous lead extraction.

BACKGROUND: Patients with cardiac implantable electronic devices (CIEDs) may no longer be eligible for continued therapy. AIMS: The study aimed to assess the circumstances under which CIED reimplantation may not be necessary after transvenous lead extraction (TLE). METHODS: A retrospective analysis of 3646 TLE procedures was performed with assessment of indications for device reimplantation. RESULTS: Reimplantation was not performed immediately after TLE in 169 (4.6%) and, in long-term follow-up, in 146 (4.0%) of patients. No further need for CIED reimplantation was mostly associated with establishment of stable sinus rhythm (2.4%), conversion of sinus node dysfunction to chronic atrial fibrillation (AF; 1.4%), or improvement in left ventricular ejection fraction (LVEF) (0.9%). Independent prognostic factors were in the pacing groups: LVEF (odds ratio [OR], 1.03; 95% confidence interval [CI], 1.01-1.05; P <0.001), AF (OR, 3.8; 95% CI, 2.4-15.7; P <0.001), patients' age during first CIED implantation (OR, 0.97; 95% C, 0.96-0.98; P <0.001), and New York Heart Association (NYHA) class (OR, 0.616; 95% CI, 0.43-0.86; P <0.01); in the cardioverter-defibrillator group: LVEF (OR, 1.06; 95% CI, 1.04-1.09; P <001). Non-reimplanted patients had more complex procedures and more frequent complications, but survival after TLE was better in this group of patients. CONCLUSIONS: Reassessment of the need for continuation of CIED therapy should be considered in all patients following lead extraction and also before planned device replacement as TLE delay increases implant duration, complexity, and procedural risk. The predictors of non-reimplantation are a younger age during the first CIED implantation, lower NYHA class, presence of AF, and higher LVEF in pacemaker carriers, and, in the defibrillator group, only higher LVEF. A decision not to reimplant does not negatively affect the long-term prognosis.

Shared Decision Making and Cardioneuroablation Allow Discontinuation of Permanent Pacing in Patients with Vagally Mediated Bradycardia.

BACKGROUND: Safe discontinuation of pacemaker therapy for vagally mediated bradycardia is a dilemma. The aim of the study was to present the outcomes of a proposed diagnostic and therapeutic process aimed at discontinuing or not restoring pacemaker therapy (PPM) in patients with vagally mediated bradycardia. METHODS: The study group consisted of two subgroups of patients with suspected vagally mediated bradycardia who were considered to have PPM discontinued or not to restore their PPM if cardioneuroablation (CNA) would successfully treat their bradycardia. A group of 3 patients had just their pacemaker explanted but reimplantation was suggested, and 17 patients had preexisting pacemakers implanted. An invasive electrophysiology study was performed. If EPS was negative, extracardiac vagal nerve stimulation (ECVS) was performed. Then, patients with positive ECVS received CNA. Patients with an implanted pacemaker had it programmed to pace at the lowest possible rate. After the observational period and control EPS including ECVS, redo-CNA was performed if pauses were induced. The decision to explant the pacemaker was obtained based on shared decision making (SDM). RESULTS: After initial clinical and electrophysiological evaluation, 17 patients were deemed eligible for CNA (which was then performed). During the observational period after the initial CNA, all 17 patients were clinically asymptomatic. The subsequent invasive evaluation with ECVS resulted in pause induction in seven (41%) patients, and these patients underwent redo-CNA. Then, SDM resulted in the discontinuation of pacemaker therapy or a decision to not perform pacemaker reimplantation in all the patients after CAN. The pacemaker was explanted in 12 patients post-CNA, while in 2 patients explantation was postponed. During a median follow-up of 18 (IQR: 8-22) months, recurrent syncope did not occur in the CNA recipients. CONCLUSIONS: Pacemaker therapy in patients with vagally mediated bradycardia could be discontinued safely after CNA.

Efficacy and safety of zero-fluoroscopy approach for ablation of atrioventricular nodal reentry tachycardia: experience from more than 1000 cases.

BACKGROUND: Radiofrequency catheter ablation (RFCA) of the slow pathway in atrioventricular nodal reentry tachycardia (AVNRT) is associated with high efficacy and low risk of total perioperative or late atrioventricular block. This study aimed to evaluate the efficacy, safety, and feasibility of slow-pathway RFCA for AVNRT using a zero-fluoroscopy approach. METHODS: Data were obtained from a prospective multicenter registry of catheter ablation from January 2012 to February 2018. Consecutive unselected patients with the final diagnosis of AVNRT were recruited. Electrophysiological and 3-dimensional (3D) electroanatomical mapping systems were used to create 3D maps and to navigate only 2 catheters from the femoral access. Acute procedural efficacy was evaluated using the isoproterenol and/or atropine test, with 15-min observation after ablation. Each case of recurrence or complication was consulted at an outpatient clinic during long-term follow-up. RESULTS: Of the 1032 procedures, 1007 (97.5%) were completed without fluoroscopy. Conversion to fluoroscopy was required in 25 patients (2.5%), mainly due to an atypical location of the coronary sinus (n = 7) and catheter instability (n = 7). The mean radiation exposure time was 1.95 ± 1.3 min for these cases. The mean fluoroscopy time for the entire study cohort was 0.05 ± 0.4 min. The mean total procedure time was 44.8 ± 18.6 min. There were no significant in-hospital complications. The total success rate was 96.1% (n = 992), and the recurrence rate was 3.9% (n = 40). CONCLUSION: Slow-pathway RFCA can be safely performed without fluoroscopy, with a minimal risk of complications and a high success rate.

Amateur Athlete with Sinus Arrest and Severe Bradycardia Diagnosed through a Heart Rate Monitor: A Six-Year Observation-The Necessity of Shared Decision-Making in Heart Rhythm Therapy Management.

Heart rate monitors (HRMs) are used by millions of athletes worldwide to monitor exercise intensity and heart rate (HR) during training. This case report presents a 34-year-old male amateur soccer player with severe bradycardia who accidentally identified numerous pauses of over 4 s (maximum length: 7.3 s) during sleep on his own HRM with a heart rate variability (HRV) function. Simultaneous HRM and Holter ECG recordings were performed in an outpatient clinic, finding consistent 6.3 s sinus arrests (SA) with bradycardia of 33 beats/min. During the patient's hospitalization for a transient ischemic attack, the longest pauses on the Holter ECG were recorded, and he was suggested to undergo pacemaker implantation. He then reduced the volume/intensity of exercise for 4 years. Afterward, he spent 2 years without any regular training due to depression. After these 6 years, another Holter ECG test was performed in our center, not confirming the aforementioned disturbances and showing a tendency to tachycardia. The significant SA was resolved after a period of detraining. The case indicates that considering invasive therapy was unreasonable, and patient-centered care and shared decision-making play a key role in cardiac pacing therapy. In addition, some sports HRM with an HRV function can help diagnose bradyarrhythmia, both in professional and amateur athletes.

Implementation of zero or near-zero fluoroscopy catheter ablation for idiopathic ventricular arrhythmia originating from the aortic sinus cusp.

Complete elimination of fluoroscopy during radiofrequency ablation (RFA) of idiopathic ventricular arrhythmias (IVAs) originating from the aortic sinus cusp (ASC) is challenging. The aim was to assess the feasibility, safety and a learning curve for a zero-fluoroscopy (ZF) approach in centers using near-zero fluoroscopy (NOX) approach in IVA-ASC. Between 2012 and 2018, we retrospectively enrolled 104 IVA-ASC patients referred for ZF RFA or NOX using a 3-dimensional electroanatomic (3D-EAM) system (Ensite, Velocity, Abbott, USA). Acute, short and long-term outcomes and learning curve for the ZF were evaluated. ZF was completed in 62 of 75 cases (83%) and NOX in 32 of 32 cases (100%). In 13 cases ZF was changed to NOX. No significant differences were found in success rates between ZF and NOX, no major complications were noted. The median procedure and fluoroscopy times were 65.0 [45-81] and 0.0 [0-5] min respectively, being shorter for ZF than for NOX. With growing experience, the preference for ZF significantly increased-43% (23/54) in 2012-2016 vs 98% (52/53) in 2017-2018, with a simultaneous reduction in the procedure time. ZF ablation can be completed in almost all patients with IVA-ASC by operators with previous experience in the NOX approach, and after appropriate training, it was a preferred ablation technique. The ZF approach for IVA-ASC guided by 3D-EAM has a similar feasibility, safety, and effectiveness to the NOX approach.

Cardiac parasympathetic modulation in the setting of radiofrequency ablation for atrial fibrillation.

The cardiac autonomic nervous system plays an important role in the genesis and maintenance of atrial fibrillation. Although, pulmonary vein isolation is the cornerstone in today's approach to atrial fibrillation ablation, a considerable proportion of patients will recur with atrial arrhythmias following this procedure, especially in the non-paroxysmal forms. The pulmonary vein isolation indirectly targets and ablate the ganglionated plexi. This might ultimately enhance the efficacy of the procedure, but an optimal ablation strategy and a reliable method to confirm and quantify the efficacy of vagal denervation following the procedure might be necessary, thus leading to significantly better results.

Association between the geographic region and the risk of familial atrioventricular nodal reentrant tachycardia in the Polish population.

Introduction: Atrioventricular nodal reentrant tachycardia (AVNRT) is one of the most common regular supraventricular arrhythmias referred for catheter ablation (CA). In Poland, several families with familial AVNRT (FAVNRT) were reported in Podkarpacie Province (PP). Objectives: We aimed to determine the frequency of FAVNRT in PP compared with other south-eastern provinces of Poland. Patients and methods: Clinical data of 1544 patients with AVNRT diagnosed by invasive electrophysiological study between 2010 and 2019 were screened for FAVNRT. From January 2017 to June 2019, patients were asked to provide details on family history and origin to obtain 3-generation pedigrees. Families with at least 2 members with previous CA of AVNRT were divided into those from south-eastern provinces (SEPs; including PP and bordering provinces [BPs]) and the remaining parts of Poland (RPP). Results: There were 932 patients from SEPs and 612 from RPP. FAVNRT was reported in 45 patients (2.91%) from 27 families, with a higher frequency in SEPs than RPP (4.02% vs 1.17%; P = 0.002) and the highest frequency in PP (6.33% vs 2.47% in BPs; P = 0.004). The risk of FAVNRT was higher in PP compared with BPs (odds ratio, 2.67; 95% CI, 1.36­5.23; P = 0.004) and similar in BPs compared with RPP (odds ratio, 2.14; 95% CI, 0.86­5.34; P = 0.1). Conclusions: A relationship exists between the geographic region and frequency of FAVNRT. A greater distance from PP was associated with less frequent FAVNRT. International cooperation and genetic testing are needed to confirm the genetic impact of FAVNRT in this part of Central Europe.

Ultrasound-guided imaging for vagus nerve stimulation to facilitate cardioneuroablation for the treatment of functional advanced atrioventricular block.

We present a case study article demonstrating successful implementation of ultrasound guided extra cardiac vagus nerve stimulation during cardioneuroablation. To our knowledge it is first published description of this technique, as most ECVS are done in the internal jugular vein bulb area. This method allows for reduction of fluoroscopy time, and most importantly reproducible vagus nerve capture especially after full bi-nodal (sinus and atrioventricular) cardioneuroablation when stimulation of vagus nerve may not give any effect in the heart. This article includes a case study with "dual component" atrioventricular block, where functional component is cured with cardioneuroablation, but structural (PR elongation) remains after procedure.

Catheter ablation of the cavotricuspid isthmus in patients with atrial flutter: predictors of long-term outcomes.

BACKGROUND: Predictors of long­term outcomes and an optimal catheter set for ablation of the cavotricuspid isthmus in patients with atrial flutter (AFL) are not well known. AIMS: This study aimed to identify predictors of clinical events following ablation. METHODS: We studied 741 patients (mean [SD] age, 62.2 [10.8] years; 248 women) who were followed for a mean (SD) time of 4.4 (2.7) years. The 2- versus 3­electrode approach and clinical predictors ofclinical events during follow­up were analyzed. RESULTS: The 2­electrode approach was faster (mean [SD] time, 62.5 [30.3] vs 101.4 [51] min; P <0.001), associated with shorter fluoroscopy time (13.1 [9.3] vs 20.3 [12.4] min; P < 0.001), cost­effective (8.29 [2.82] vs 11.89 [2.51] units; P <0.001), and more effective (92.1% vs 86.1%; P = 0.012). The independent predictors of AFL recurrence were: calcium blocker use (hazard ratio [HR], 3.24; 95% CI, 1.64-6.4), mitral valve disease (HR, 1.82; 95% CI, 1.12-2.95), previous stroke and/ or TIA (HR, 2.38; 95% CI, 1.21-4.65), pulmonary artery dilatation (HR, 3.94; 95% CI, 1.22-12.73), and previous pulmonary embolism (HR, 3.77; 95% CI, 1.14-12.43); of atrial fibrillation (AF): previous AF (HR, 6.054; 95% CI, 4.58-8), left atrial enlargement (HR, 1.43; 95% CI, 1.12-1.81), number of antiarrhythmic drugs used (HR, 1.16; 95% CI, 1.05-1.28), and mitral valve disease (HR, 1.28; 95% CI, 1.04-1.58); of pacemaker implantation: tachycardia­bradycardia syndrome (HR, 6.17; 95% CI, 3.16-12.05), previous second-/third­degree atrioventricular block (HR, 29.4; 95% CI, 7.37-117.28), centrally acting hypotensive drugs (HR, 29.55; 95% CI, 6.14-142.25), aortic dilatation or aneurysm (HR, 2.58; 95% CI, 1.06-6.3), a labile international normalized ratio (HR, 3.45; 95% CI, 1.72-6.93), left bundle branch block (HR, 4.7; 95% CI, 1.49-14.82), the shortest R­R interval during AFL (HR, 1.003; 95% CI, 1.001-1.005), previous cardiac surgery (HR, 2.69; 95% CI, 1.27-5.7), and aortic valve disease (HR, 2.22; 95% CI, 1.08-4.59). CONCLUSION: Ablation of cavotricuspid isthmus with a minimal number of electrodes is safe and effective. Specific predictors of clinical events during long­term follow-up can be determined.