Atrioventricular Node Ablation Research Articles

Complementary use of conduction system pacing techniques for the “pace and ablate” strategy in permanent atrial fibrillation - a case report

Abstract Introduction The feasibility of the conduction system pacing combined with atrioventricular node ablation was demonstrated in patients with atrial fibrillation in whom rate control can’t be achieved with medication and heart failure. Clinical case We present a case of an 82-year-old man with a personal history of permanent atrial fibrillation, admitted with symptoms of heart failure. The resting electrocardiogram showed a very fast ventricular response, and the echocardiography showed a depressed left ventricular function, raising the suspicion of a tachycardia-mediated cardiomyopathy. Since the patient was on maximum doses of atrioventricular nodal-blocking drugs, we opted for a physiological pacing and atrioventricular node ablation strategy. First, the His bundle capture was achieved at low pacing thresholds, and ablation of the atrioventricular node was attempted. Unfortunately, after several failed attempts, an acute increase in the His bundle capture threshold was noted, suggesting inadvertent tissue ablation beneath the pacing lead. In this scenario, we removed the lead from the His bundle area and achieved optimal left bundle branch area pacing. With the lead in this position, atrioventricular node ablation was performed during the first attempt. At the six-month follow-up, there was no recovery of atrioventricular node conduction. Device interrogation revealed stable pacing and sensing parameters, and there was a significant improvement in clinical status and left ventricular function. Conclusions Mastering both His bundle pacing and left bundle branch area pacing offers the potential to overcome intraprocedural challenges, giving alternative strategies to achieve physiological pacing. These approaches can be used interchangeably based on the evolving dynamics of the procedure and the patient’s specific needs.

Single center experience of efficacy and safety of atrioventricular node ablation after left bundle branch area pacing for the management of atrial fibrillation

Abstract Introduction Atrioventricular node ablation (AVNA) with permanent pacing is an effective treatment of symptomatic atrial fibrillation (AF). Permanent right ventricular pacing is associated with cardiac dyssynchrony, which can worsen heart failure (HF) symptoms. Left bundle branch area pacing (LBBAP) is a recent pacing technique, more physiologic and less associated with cardiac dyssynchrony. Purpose To evaluate feasibility, safety and outcomes at 6 months of AVNA associated with LBBAP in patients with symptomatic AF. Methods In this retrospective monocentric study, we included all consecutive patients treated with AVNA procedure and LBBAP. Procedures characteristics, clinical follow-up, electrical and echographic data at baseline and 6 months were studied and compared to the data of a matched cohort (1:1) of patients who received an AVNA procedure with conventional pacing between March 2010 and February 2023. Results 75 AVNA procedures and LBBAP were studied. The success rate of AVNA was 98.7% at first ablation without any complications, especially no lead dislodgement or threshold rise. Pacing electrical parameters at implant were good, and stable at 6 months follow-up, with no threshold rise. At 6 months, 4 (5%) patients were hospitalized for heart failure and 1 (1.3%) was deceased. Patients had a significative improvement in NYHA class, palpitations symptoms, and left ventricular ejection fraction (LVEF) (p ≤ 0.0001 for all). After matching with a cohort of patients with AVNA and conventional pacing (n=68), patients with LBBAP had a significantly better improvement of LVEF (+5.27±9.62% versus -0.48±14%; p = 0.01), and a lower rate of a composite endpoint (all cause death and hospitalization for HF) (HR 0.34, 95%CI: 0.1-1.06; p = 0.064). Conclusions AVNA with LBBAP in patients with symptomatic AF was feasible and safe. Complication rate and adverse outcomes at 6 months were similar to AVNA with conventional pacing, and LVEF improvement was significantly greater.Matched populationsOutcomes at 6 months

Atrial fibrillation burden, symptoms and medication use after left bundle branch area pacing combined with AV-node ablation in patients with symptomatic atrial fibrillation

Abstract Background AV node ablation combined with permanent pacing is an established therapy for rate control in patients with symptomatic atrial fibrillation (AF) refractory or intolerant to pharmacological rate or rhythm control and not eligible for rhythm control by left atrial catheter ablation. The threshold for performing this so-called "pace-and-ablate" strategy has decreased since the introduction of conduction system pacing, and especially left bundle branch area pacing (LBBAP). Purpose To investigate the AF burden, AF related symptoms and anti-arrhythmic drug (AAD) use after AV-node ablation combined with LBBAP. Methods Consecutive patients with symptomatic AF, intolerant or refractory to pharmacological rate and symptom control and deemed not eligible for left atrial catheter ablation, were included. At baseline, AF related symptoms classified according to the EHRA classification and AAD use were scored. After DDD-pacemaker implantation with an LBBAP lead and subsequent AV-node ablation device detected AF burden was assessed six weeks, six months and twelve months later. AF burden at six weeks after AV-node ablation was considered the baseline measurement for AF burden. AF related symptoms and AAD use were collected at twelve months follow-up. Results Twenty-four patients (67% female, mean age 79±4 years) scheduled for pace-and-ablate therapy were prospectively included. Eighteen patients had persistent (75%) and three long-standing persistent (12.5%) AF with enlarged left atria (left-atrial volume index (LAVI) 52 ± 18ml/m2) and EHRA class IIb or higher in twenty (69%) patients. Twenty-three patients (96%) used at least one AAD with fifteen patients (63%) using >1 AAD at baseline, fig. 1. AF burden did not change at six months (-1.3 [-17, 15] %, p=0.87) and twelve months (-2.9 [-40,35] %, p=0.86) follow-up relative to six weeks follow-up, fig 2A. AF symptoms were significantly reduced with most patients in EHRA class I (6, 25%) or class IIa (17, 71%; p<0.001) at twelve months follow-up, fig 2B. There was a significant reduction in AAD use with fourteen patients (58%) using no AAD at twelve months follow-up and no patients using >1 AAD at twelve months follow up (p<0.001), fig 2C. Conclusion AV node ablation followed by permanent LBBAP did not reduce AF burden in an AF population with advanced disease. However, a significant reduction in AF symptoms and medication use was demonstrated with this therapy. Figure 2. AF burden (panel A), symptoms (panel B) and AAD use (panel C) at baseline and twelve months after ‘pace-and-ablate’ therapy. AF = atrial fibrillation; EHRA = EHRA = European Heart Rhythm Association symptom classification for AF; AAD = anti-arrhythmic drug. *relative to AF burden at six weeks follow-up.Baseline characteristicsBaseline and follow-up measurements

AV nodal ablation in atrial fibrillation: long term outcomes

Abstract Background Ablation of the atrioventricular (AV) node, following the insertion of a permanent pacemaker, is a treatment option for symptomatic atrial fibrillation (AF) where rate control is poor, despite maximally tolerated pharmacological intervention or percutaneous AF ablation [1], and yet there is limited data on long-term outcomes. Purpose The purpose of this study is to investigate post AV node ablation follow up outcomes, including the incidence and timeframe of conversion of paroxysmal to persistent AF; incidence and timeframe of upgrade to biventricular pacemakers; and mortality. Methods This observational descriptive study looked at the post-procedure follow-up outcomes of patients who underwent AV node ablation at our centre between March 2015 and June 2019. Retrospective analysis of prospectively collected data was analysed. The demographics of the patients, including their age, gender, co-morbidities, pre-ablation left ventricular ejection fraction (LVEF) and medications were recorded. The follow up outcomes investigated included the change in LVEF, the proportion of patients whose AF converted from paroxysmal to persistent, the proportion of patients requiring upgrade to biventricular devices, and deaths within 6 months of ablation. Outcomes were compared between those who had a biventricular pacemaker pre-ablation and those who had single/dual chamber pacemakers. Results 296 patients with a mean age of 72.7± 8.5 years and a female to male ratio of 54.1% : 45.9% were included. 94 patients (31.8%) had paroxysmal AF pre- ablation. 51.6% of those who had paroxysmal AF pre-ablation converted to persistent AF over a median period of 3 years (interquartile range, 3 years). Among those who had a biventricular pacemaker pre-ablation, 56.5% of those with paroxysmal AF converted to persistent, compared to 47.4% of those with a dual pacemaker pre-ablation p=ns Among patients with dual chamber pacemakers, those who remained in paroxysmal AF post-ablation had a mean CHADVASC score of 3.2 (range of 1-6) compared to 3.7 (range of 2-6) in those whose AF converted to persistent (p=0.19). 9 patients (3%) died within less than 6 months of the procedure, with 1 patient dying within 6 days. 13% of the patients originally having a single or dual chamber pacemaker required an upgrade to a biventricular pacemaker over a median period of 1.25 years (interquartile range 1.1 years). All the patients who required an upgrade to a biventricular pacemaker had normal LVEF pre-ablation except for one patient who had mild LV impairment. Conclusions A significant proportion of patients with paroxysmal AF converted to persistent AF following AV node ablation and having a biventricular pacemaker did not offer benefit in keeping people in paroxysmal AF.A considerable number of people required an upgrade to biventricular pacemaker over a short time frame even though they had normal LVEF pre AV nodal ablation.

Echocardiographic follow-up after AV node ablation combined with left bundle branch area pacing for patients with symptomatic atrial fibrillation

Abstract Background AV node ablation combined with permanent pacing is an established therapy for rate control in patients with symptomatic atrial fibrillation (AF) refractory or intolerant to pharmacological rate or rhythm control and not eligible for rhythm control by left atrial catheter ablation. The threshold for performing this so-called "pace-and-ablate" strategy has decreased since the introduction of conduction system pacing, and especially left bundle branch area pacing (LBBAP). Purpose To investigate the change of the left-ventricular (LV) ejection fraction (EF) and left-atrial volume index (LAVI) in patients with symptomatic AF, twelve months after LBBAP and AV-node ablation. Methods Consecutive patients with symptomatic AF intolerant or refractory to pharmacological rate and symptom control and deemed not eligible for left atrial catheter ablation were included. At baseline, the EHRA score was noted and the LVEF and LAVI were measured echocardiographically. Patients were subdivided in a normal baseline LV ejection fraction (LVEF >50%) or diminished baseline LVEF (LVEF <50%) group. After LBBAP, patients underwent AV node ablation in the same procedure or four weeks later. After twelve months, the LVEF and LAVI were reassessed in the entire cohort and the two subgroups. Results Twenty-two patients (68% female, mean age 79±4 years) scheduled for pace-and-ablate therapy were prospectively included. Three (14%) had paroxysmal, sixteen patients (72%) had persistent AF and three patients (14%) long-standing persistent AF. An EHRA class IIb or higher was found in eighteen patients (82%). At baseline, the mean LVEF was 51 ± 7%, the mean LVEDD 47 ± 6 mm and LAVI 54 ± 18 ml/m2. Twelve patients (55%) had a preserved LVEF, whereas ten patients (45%) had an LVEF <50%, fig. 1. After twelve months, the overall ejection fraction increased to 54 ± 5% (p=0.016), fig. 2A. This was mostly attributed to the increase in LVEF to 51 ± 5% in the subgroup with a reduced baseline LVEF (p=0.009 compared to baseline 44 ± 5%), fig. 2A. The LVEF was unaffected in the other group (57 ± 3% vs. 57 ± 4%, p=0.63), fig. 2A. The LAVI was not significantly reduced in the overall cohort or the subgroups (54 ± 18 ml/m2 to 51 ± 19 ml/m2, p=0.16), fig 2B. Conclusion AV node ablation combined with LBBAP results in a significant improvement in LVEF at twelve months follow-up. This is mainly driven by an improvement in LVEF in those patients with a diminished LVEF at baseline. The data suggests that the therapy can reverse a tachycardiomyopathy without inducing a pacing-induced cardiomyopathy. No significant reduction in LAVI was found.Baseline characteristicsChanges in LVEF (A) and LAVI (B)

Not too old to be treated: electrophysiological study and catheter ablation in eldery patients

Abstract Background The number of elderly patients referred for electrophysiological study (EPS) and catheter ablation (CA) is increasing. These patients are thought to have more complications due to age and comorbidity. Purpose The aim of our study was to evaluate the safety (EPS and CA) and acute success (CA) in a group of elderly patients (age ≥75 years old). Methods Between August 2020 and September 2023, consecutive elderly patients (32.7% older than 80 years) underwent EPS alone or EPS and CA at our center. Left atrial thrombus was ruled out performing transesophageal echocardiography when indicated. Anticoagulation (ACO) was not interrupted. Femoral veins, arteries and transeptal punctures were performed under ultrasound guidance. A navigation system was used for all CA procedures, except for pulmonary vein isolation, which was performed with a cryoballoon. We analysed procedural complications related to EPS and CA and the acute success of CA procedures. Results A total of 104 patients undergoing EPS±CA (79.9±4.6 years, 41.3% female, 75% HTA, 67.3% diabetes type 2, 19.4% COPD, 20.2% chronic renal disease, 25% structural heart disease, CHA2DS2VasC score 3.6±0.8, IMC 27.3±4.5 kg/m2, weight 72.3±13.6 kg, LVEF 52.7±10.8%, 31% history of atrial fibrillation (AF), 47.1% on ACO, 38.5% bundle-branch block, 34.6% first-degree atrioventricular block, 4.8% implanted pacemaker or ICD) were included. Indications for referral (Figure 1) were typical atrial flutter (TAF, 34.6%), atrioventricular nodal reentrant tachycardia (AVNRT, 26.9%), study of syncope (11.5%) atypical atrial flutter or atrial tachycardia (AAF/AT, 10.6%), AF (8.6%, 6 patients for AV node ablation, 3 for pulmonary vein isolation), ventricular tachycardia or ectopy (VT or VE, 5.7%), orthodromic reentrant tachycardia (ORT, 1.9%). 2 patients had TAF and AVNRT, treated in the same procedure. Acute success was achieved in 100% of AF, 94.6% of TAF, 89.6% of AVNRT, 66% of VT/VE, 50% of ORT, 45% of AAF/AT. There were 4 complications (2.9%) in 3 patients, all during the CA procedure: an AV block during an AVNRT ablation, another AV block during an ischaemic septal VT ablation, a femoral artery pseudoaneurism in the same patient (femoral artery approach), and a dislocation of the electrodes from a previous pacemaker during an AT ablation. None of the patients undergoing EPS alone had complications. Weight was the only variable associated with the development of complications (mean difference= -19.8, 95% CI(-38.9-0.7); p=0.04), being higher in those with than in those without complications (91.5±2.2 vs 71.6±13 Kg),(Table 1). Conclusions EPS and CA procedures in elderly patients with multiple comorbidities are safe and effective. Acute success and complication rates of CA procedures are substrate-dependent and similar to those reported in the literature for younger patients. We conclude that age is not a barrier to the study and treatment of arrhythmias.

Cryoballoon versus radiofrequency catheter ablation: 3-year follow-up data from the prolonged Norwegian randomized study of persistent atrial fibrillation (NO-PERSAF study)

Abstract Background Pulmonary vein isolation (PVI) is still regarded as a cornerstone for treatment of persistent atrial fibrillation (AF). Both radiofrequency ablation (RFA) and cryoballoon ablation (CBA) are frequently employed to achieve PVI. Similar results of both techniques have been reported during short follow-up, but clinical outcomes for long-term follow-up from randomized trials are still missing. Purpose This study aimed to evaluate the effectiveness of PVI performed with CBA compared with RFA in patients with persistent AF over 3 years. Methods For the NO-PERSAF study, 101 patients (63.2±8.6 years old, 80 male, 21 female), with persistent AF (77 persistent AF, 24 long-standing persistent AF) referred to PVI were randomized (1:1) to CBA or RFA and followed for 12 months. All patients participating in the NO-PERSAF study were invited to an extended outpatient evaluation with 12-lead ECG and 7-day Holter. The primary endpoint was any documented recurrent atrial tachyarrhythmia (ATA) lasting longer than 30 s during 3 years after the index ablation procedure (following a 3-month blanking period). The ATA-free survival curves were estimated by Kaplan-Meier method and analyzed by log-rank test. Results One patient crossed over from CBA to RFA group because of equipment problem during index ablation procedure. 99 of the original 101 patients responded (1 died of non-cardiovascular diseases, 1 lost). Freedom from ATA was achieved in 51 (50.5%) of the 101 patients, 28 (54.9%) out of 51 patients in the CBA group and 23 (46.0%) out of 50 patients in the RFA group (Figure 1). No difference of ATA recurrence was found between the two groups (p=0.327). There was significantly (p=0.031) less atrial flutter in the CBA group (7.8%; 4 atypical) compared with the RFA group (22%; 10 atypical, 1 typical). 28 patients received repeat ablations with RFA during the follow-up period, 15 in the CBA group and 13 in the RFA group (1 twice). Freedom from ATA after multiple ablations was achieved in 74 (73.3%) of the 101 patients, 40 (78.4%) out of the 51 patients in the CBA group and 34 (68.0%) out of the 50 patients in the RFA group. No difference of ATA recurrence was found between the two groups (p=0.178, Figure 2) after multiple ablations with RFA for AF and atrial flutter. Noticeably, 2 patients in the CBA group and none in the RFA group received atrioventricular nodal ablation after permanent pacemaker implantation. Conclusions Compared to RFA, PVI performed with CBA showed similar outcome of freedom from ATA over a long-term follow-up of 3 years. However, the incidence of atrial flutter was significantly lower in the CBA group.Figure 1Figure 2

Temporal evolution of His bundle pacing thresholds: a sub-study of the PACE-CONDUCT trial

Abstract Background His bundle pacing (HBP) has become a valuable alternative for cardiac resynchronization therapy, offering physiological pacing. This substudy of the PACE-CONDUCT trial aimed to explore the influence selective and non-selective HBP on threshold height. We assessed these parameters in patients with both normal conduction and bundle branch block conduction. Methods Our study included 61 consecutive patients with a median age of 73 years, who underwent a successful HBP implantation for indications such as sick sinus syndrome, AV Block 2 type 2, binodal disease, and ablate and pace therapy prior to AV-node ablation. Among these patients, 18 exhibited QRS durations exceeding 150 ms, indicating a complete and broad bundle branch block which made them candidates for cardiac resynchronization therapy (CRT). All patients received HBP implantation with the assistance of a 3D electroanatomical system. This system allowed for low-fluoroscopic, atraumatic evaluation of the His bundle (HB) area, presenting the His voltage as a color-coded map for precise electrode placement. Results The feasibility of bundle branch correction is generally accepted in selective HBP distal to the site of block, albeit associated with higher threshold values and potentially lower battery duration. Our analysis encompassed 61 patients who underwent HBP implantation, with 23 patients (37,7%) exhibiting selective HBP and 38 (62,3%) non-selective HBP. Remarkably, 10 out of the 23 patients with selective HBP demonstrated a complete bundle branch block correction after HBP implantation even with a basal QRS durations exceeding 150 ms. We evaluated HBP thresholds at implantation, one day post-implantation, and one month post-implantation, correlating these data with selective and non-selective HBP. Threshold values were converted to volts per millisecond (volts × milliseconds) for analysis. Statistical analysis conducted with IBM SPSS 29.0 revealed a significant difference at the day of implantation, indicating higher threshold capture in selective HBP compared to non-selective HBP (one-sided p-value: < 0.01, two sided p value 0.01). However, this difference could not be sustained at the one-day and one-month threshold follow-ups, suggesting normalization of the selective HBP threshold. Conclusion In our study, the initially higher threshold in selective HBP normalized within 24 hours compared to non-selective HBP. Additionally, our study demonstrated the feasibility of selective His pacing in patients with complete bundle branch block and broad QRS durations. These findings provide insights into HBP optimization and encourage further investigations with larger patient cohorts to validate our observations and enhance patient care in the realm of cardiac pacing.Threshold trend

Safety of catheter ablation in patients with recently implanted cardiac implantable electronic device: A 5-year experience.

Catheter ablation (CA) can interfere with cardiac implantable electronic device (CIED) function. The safety of CA in the 1st year after CIED implantation/lead revision is uncertain. This single center, retrospective cohort included patients who underwent CA between 2012 and 2017 and had a CIED implant/lead revision within the preceding year. We assessed the frequency of device/lead malfunctions in this population. We identified 1810 CAs in patients between 2012 and 2017, with 170 CAs in 163 patients within a year of a CIED implant/lead revision. Mean age 68±12 years (68% men). Time between the CIED procedure and CA was 158±99 days. The CA procedures included AF ablation (n=57, 34%), AV node ablation (n=40, 24%), SVT ablation (n=37, 22%), and PVC/VT ablations (n=36, 21%). The cumulative frequency of lead dislodgement, significant CIED dysfunction, and/or CIED-related infection following CA was (n=1/170, 0.6%). There was a single atrial lead dislodgement (0.6%). There were no instances of power-on-reset or CIED-related infection. Following CA, there was no significant difference in RA or RV lead sensing (p=0.52 and 0.84 respectively) or thresholds (p=0.94 and 0.17 respectively). The RA impedance slightly decreased post-CA from 474±80 Ohms to 460±73 Ohms (p=0.002), as did the RV impedance (from 515±111 Ohms to 497±98 Ohms, p<0.0001). CA can be performed within 1 year following CIED implantation/lead revision with a low risk of CIED/lead malfunction or lead dislodgement. The ideal time to perform CA after a CIED remains uncertain.

Outcomes of combined left bundle branch area pacing with atrioventricular nodal ablation in patients with atrial fibrillation and pulmonary disease.

Concomitant left bundle branch area pacing (LBBAP) with atrioventricular (AV) nodal ablation is emerging as a viable management option in atrial fibrillation refractory to medical management. Its viability in patients with pulmonary disease and atrial fibrillation is unknown. This is a retrospective, observational cohort study in consecutive patients who underwent concomitant LBBAP with AV nodal ablation with advanced pulmonary disease at the Cleveland Clinic Fairview Hospital between January 2019 and January 2023. Patient characteristics, comorbidities, and medication use were extracted via chart review. Rates of hospitalizations, medication use, and structural disease seen on echocardiography were compared before and after the procedure. There were 27 patients with group 3 pulmonary hypertension who underwent the procedure. In the 24 months preprocedure, there were 114 admissions for heart failure or atrial fibrillation compared to 9 admissions postprocedure (p<.001). Mean follow up was 17.3±12.1 months. There were no significant complications or lead dislodgements. Echocardiographic characteristics were similar prior to and after pacemaker implantation. Use of medications for rate and rhythm control was common preprocedure, and was reduced dramatically postprocedure. This small, retrospective cohort study suggests concomitant LBBAP with AV nodal ablation may be safe and efficacious for management of atrial fibrillation in patients with advanced pulmonary disease.

Editorial to predictors of the need for atrioventricular nodal ablation following redo ablation for atrial fibrillation

Editorial to predictors of the need for atrioventricular nodal ablation following redo ablation for atrial fibrillation

Predictors of the need for atrioventricular nodal ablation following redo ablation for atrial fibrillation

AbstractBackgroundPatients who have recurrent atrial fibrillation (AF) following redo catheter ablation may eventually be managed with a pace‐and‐ablate approach, involving pacemaker implant followed by atrioventricular nodal ablation (AVNA). We sought to determine which factors would predict subsequent AVNA in patients undergoing redo AF ablation.MethodsWe analyzed patients undergoing redo AF ablations between 2013 and 2019 at our institution. Follow‐up was censored on December 31, 2021. Patients with no available follow‐up data were excluded. Time‐to‐event analysis with Cox proportional hazard regression was used to compare those who underwent AVNA to those who did not.ResultsA total of 467 patients were included, of whom 39 (8.4%) underwent AVNA. After multivariable adjustment, female sex (aHR 4.68 [95% CI 2.30–9.50]; p &lt; 0.001), ischemic heart disease (aHR 2.99 [95% CI 1.25–7.16]; p = 0.014), presence of a preexisting pacemaker (aHR 3.25 [95% CI 1.10–9.60]; p = 0.033), and persistent AF (aHR 2.22 [95% CI 1.07–4.59]; p = 0.032) were associated with increased risk of subsequent AVNA requirement.ConclusionFemale sex, ischemic heart disease, and persistent AF may be useful clinical predictors of the requirement for subsequent AVNA and may be considered as part of shared clinical decision making.

Modern physiological approach to inappropriate ICD shocks due to atrial fibrillation with very fast ventricular response. A case report

BackgroundFast-conducting atrial fibrillation misinterpreted as ventricular tachycardia is the leading cause for inappropriate shocks in patients with implantable cardiac defibrillators (ICD). These inappropriate shocks are associated with significant morbidity and mortality and cause great discomfort and stress.Case presentationWe report the case of a patient with ischemic cardiomyopathy, permanent atrial fibrillation, and a single-chamber DF-1 ICD implanted for the primary prevention of sudden cardiac death, who presented for multiple inappropriate internal shocks due to very fast-conducting atrial fibrillation, which was mislabeled as ventricular fibrillation by the ICD. Since the patient was under maximal atrioventricular nodal blocking medical therapy (beta-blockers and digitalis) and we didn`t find any reversible causes for the heart rate acceleration, we opted for rate control with atrioventricular node ablation. To counteract the risk of pacing-induced cardiomyopathy in this patient who would become totally pacemaker-dependent, we successfully performed left bundle branch area pacing. Because the patient`s ICD had a DF-1 connection and the battery had a long life remaining, we connected the physiological pacing lead to the IS-1 sense-pace port of the ICD. The 6-month follow-up showed an improvement in left ventricular function with no more inappropriate shocks.ConclusionsLeft bundle branch area pacing and atrioventricular node ablation in patients with an implantable single-chamber DF-1 defibrillator and fast-conducting permanent atrial fibrillation is a cost-efficient and very effective method to prevent and treat inappropriate shocks, avoiding the use of an additional dual-chamber or CRT-D device.

Silent pulmonary veins at redo ablation for atrial fibrillation: Implications and approaches.

Pulmonary vein isolation (PVI) is the cornerstone of atrial fibrillation (AF) ablation. Despite promising success rates, redo ablation is sometimes required. At redo, PVs may be found to be isolated (silent) or reconnected. We studied patients with silent vs reconnected PVs at redo and analysed associations with adverse outcomes. Patients undergoing redo AF ablations between 2013 and 2019 at our institution were included and stratified into silent PVs or reconnected PVs. The primary outcome was a composite of further redo ablation, non-AF ablation, atrioventricular nodal ablation, and death. Secondary outcomes included arrhythmia recurrence. A total of 467 patients were included with mean 4.6 ± 1.7 years follow-up, of whom 48 (10.3%) had silent PVs. The silent PV group had had more often undergone >1 prior ablation (45.8% vs 9.8%; p<0.001), had more persistent AF (62.5% vs 41.1%; p=0.005) and had more non-PV ablation performed both at prior ablation procedures and at the analysed redo ablation. The primary outcome occurred more frequently in those with silent PVs (25% vs 13.8%; p=0.053). Arrhythmia recurrence was also more common in the silent PV group (66.7% vs 50.6%; p=0.047). After multivariable adjustment, female sex (aHR 2.35 [95% CI 2.35-3.96]; p=0.001) and ischaemic heart disease (aHR 3.21 [95% CI 1.56-6.62]; p=0.002) were independently associated with the primary outcome, and left atrial enlargement (aHR 1.58 [95% CI 1.20-2.08]; p=0.001) and >1 prior ablation (aHR 1.88 [95% CI 1.30-2.72]; p<0.001) were independently associated with arrhythmia recurrence. Whilst a finding of silent PVs was not itself significant after multivariable adjustment, this provides an easily assessable parameter at clinically indicated redo ablation which informs the clinician of the likelihood of a worse future prognosis. Patients with silent PVs at redo AF ablation have worse clinical outcomes.

Lead Dislodgement Post Invasive Hemodynamic Assessment after Atrioventricular Node Ablation and Biventricular Pacemaker

A man with history of Heart Failure with preserved Ejection Fraction (HFpEF), Atrioventricular (AV) node ablation followed by biventricular pacemaker placement was hospitalized for dyspnea. During invasive hemodynamic assessment patient had brief episode of asystole due to lead displacement. Right catheterization should be cautiously performed in patients with intracardiac devices, when done safety protocols should be followed.

Conversion to Sinus Rhythm in Refractory Atrial Fibrillation Patients after Atrioventricular Node Ablation with Conduction System Pacing

Conversion to Sinus Rhythm in Refractory Atrial Fibrillation Patients after Atrioventricular Node Ablation with Conduction System Pacing

Feasibility and Safety Study of Concomitant Left Bundle Branch Area Pacing and Atrioventricular Node Ablation with Same-Day Hospital Dismissal.

Left bundle branch area pacing (LBBAP) has rapidly emerged as a promising modality of physiologic pacing and has demonstrated excellent lead stability. In this retrospective study, we evaluate whether this pacing modality can allow concomitant atrioventricular node (AVN) ablation and same-day dismissal. Twenty-four consecutive patients (female 63%, male 37%) with an average age of 78 ± 5 years were admitted for pacemaker (75%)/defibrillator (25%) implantations and concomitant AVN ablation. Device implantation with LBBAP was performed first, followed by concomitant AVN ablation through left axillary vein access to allow for quicker post-procedure ambulation. The patients were discharged on the same day after satisfactory post-ambulation device checks. LBBAP was successful in 22 patients (92% in total, 20 patients had an LBBP and two patients had a likely LBBP), followed by AVN ablation from left axillary vein access (21/24, 88%). All patients had successful post-op chest x-rays, post-ambulation device checks, and were discharged on the same day. After a mean follow up of three months, no major complications occurred, such as LBBA lead dislodgement requiring a lead revision. The LBBA lead pacing parameters immediately after implantation vs. three-month follow up were a capture threshold of 0.8 ± 0.3 V@0.4 ms vs. 0.6 ± 0.3 V@0.4 ms, sensing 9.9 ± 3.9 mV vs. 10.4 ± 4.1 mV, and impedance of 710 ± 216 ohm vs. 544 ± 110 ohm. The QRS duration before and after AVN ablation was 117 ± 32 ms vs. 123 ± 14 ms. Mean LVEF before and three months after the implantation was 44 ± 14% vs. 46 ± 12%. LBBA pacing not only offers physiologic pacing, but also allows for a concomitant AVN ablation approach from the left axillary vein and safe same-day hospital dismissal.

High-power short-duration ablation of the atrioventricular node

Abstract Introduction There are limited studies that compare different radiofrequency ablation catheters in atrioventricular node (AVN) ablation. Our study compared the effectiveness of several radiofrequency ablation catheters in AVN ablation. Methods We identified patients who underwent AVN ablation at our institution. Data related to patients and procedures were collected through retrospective chart review. The radiofrequency catheters compared were plain non-irrigated, externally irrigated (EI), and contact force sensing in two different settings: low-power long duration (LPLD) and high-power short duration (HPSD). We compared the different catheters in terms of success rate using logistic regression and lesion time using linear regression. Results We identified 66 patients who underwent AVN ablation, out of which 31 were female (47%). The patients were elderly, with a mean age of 73.27 years. The indications were resistant atrial fibrillation in 74%, atrial flutter in 18%, and other atrial tachycardias in 8% of patients. Types of catheters used were plain non-irrigated in 48%, EI in 2%, LPLD in 16%, and HPSD in 34% of patients. All ablation procedures were successful with no immediate post-procedure complications. Regarding lesion time, HPSD was significantly shorter compared to plain catheters by 403.42s[-631.67, -175.17] as shown in table 1. Conclusions While plain catheter, LPLD, and HPSD were equally safe and effective, HPSD catheter had significantly shorter lesion time and thus procedure time.

Real-time interactive 3d simulation of Atrial Fibrillation for education

Abstract Background The mechanistic understanding of atrial fibrillation (AF) has burgeoned over the past decades. However, the interplay between triggers, reentry, drivers and therapies is rarely fully appreciated despite being ultimately fundamental to patient care. Readily accessible, high-fidelity interactive simulation has the potential to address this knowledge gap across healthcare providers. Objective To develop a, interactive simulation system to allow deep understanding of AF mechanisms and therapies. Methods An application for e-Training was developed to be accessible on consumer smartphones and tablets, based on a validated electromechanical simulation model of the heart, with real-time interactive 3D image output. A virtual heart is represented in normal and arrhythmic states, enabled with simulated models for administering antiarrhythmic drugs, performing Pulmonary Vein Isolation (PVI), AV Node ablation, ventricular pacing, DC Cardioversion, plus the formation of atrial thrombus leading to a stroke event. Electrogram and ECG signals are generated from the underlying simulation and respond realistically to drugs, pacing and ablation. A self-study tutorial introduces the arrhythmia and treatment procedures. Learning outcomes are assessed with MCQ tests and receive Continuous Professional Development CPD credits. Results The AFib Sim app has received CPD accreditation in the UK and has so far been used at the Universities of Oxford, Cambridge and Leeds medical schools. All trainees and medical students followed the self-study tutorials and took the interactive MCQ test, which are embedded within the AFib Sim app. Development was based on Unity 3D and was made available on iOS, Android, macOS, MS Windows and WebGL platforms. Conclusion This project meets an urgent training need whilst expanding expertise and market scope into clinical training. The impact on clinical training was high and the societal benefit came from better and quicker trained staff. Learning Objective Upon completion of this session, the attendee will be able understand how a simulation of Atrial Fibrillation can be used for training and deepening the clinical understanding of atrial fibrillation.

Cardiac resynchronosation and left ventricular ejection fraction improvement with single ventricular conduction pacing system lead

Abstract Background Conduction system pacing is a new modality to obtain physiologic pacing (PP) and normal to near normal cardiac synchrony; they often obtain shorter QRS durations and they could replace the need of Bi-V (CRT) implants if LVEF improves as much with less leads implanted. Methods From our cohort of 340 physiologic pacing attempts (2019-2023), we extracted all patients (pts) with available ultrasounds before and after implants, aiming to describe the variation of Left Ventricular Ejection Fraction (LVEF) over time; all attempts, including failures were analyzed. Results A total of 146 pts completed follow-up LVEF evaluation. Pts were 36,8% females; median age was 79 +/- 8.5 years. Indications were: SSS 25%, AV block 41% (including 11 post TAVR), Pacemaker induced cardiomyopathy (PIMC) 27% and AV node ablation in 7%. Success to achieve cardiac resynchronisation (defined as a QRS shorter than 140ms and a LVAT shorter than 90ms, or 20% reduction in QRS width) was obtained in 82,6% of pts (higher success rate achieved with LBB-P: 88,4% vs 55,5% for His-P). Procedural time (pts in-out) was 88min (+/- 37min). Pts with a QRS larger than 150ms (CRT indication) were 49% of the cohort. Patients with a LVEF less than 50% accounted for 54,8% of the cohort. Mean QRS duration was 141,9ms (+/-36) pre-implant and 129,3ms (+/- 19) post implant. Mean LVEF was 43,6% (+/- 14) before implant and increased to 50,2% (+/-12) post implant for the entire cohort, in pts with CRT indication, variation persisted: mean LVEF improved from 33,2 to 43,8% and QRS duration from 172,9 to 136,8ms. Pts with less than 50% LVEF had a response rate of 75,5% (increase in LVEF from 4-41%), and 33% of patients increase their LEVF between 10-30% (deemed super responders), only one pt decrease 10% her LVEF (a His failure implant). Conclusion Cardiac resynchronisation is feasible with only one ventricular lead, potentially with longer duration of batteries and lesser costs. Response rate is similar to CRT historical controls but super responders are twice to three times higher than historical controls.