Symptomatic Atrial Fibrillation Research Articles

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

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)

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

Impact of early recurrences on late recurrences after pulmonary vein isolation with pulsed field ablation. A subanalysis from the EU-PORIA multicenter international registry

Abstract Background Early recurrences of atrial tachyarrhythmia (ERAT) are commonly observed after pulmonary vein isolation (PVI) with thermal energies. ERAT during the 90-day blanking period (BP) should not be considered therapy failure as the cardiac tissue is still healing and the long-term benefit of PVI may not be immediately apparent. With the introduction of pulsed field ablation (PFA), a non thermal, myocardial-specific ablation technology for atrial fibrillation (AF), the significance of ERAT following PVI is unclear. Methods EU-PORIA (EUropean real-world outcomes with Pulsed field ablatiOn in patients with symptomatic atRIAl fibrillation), a multicentre international registry, collected data from 1233 patients treated with the pentaspline PFA catheter. For the current analysis, patients with a previous AF ablation procedure, patients treated with lesions beyond PVI, and patients without complete follow up data (during and following the BP) were excluded. The rate and significance of ERAT following PFA PVI were analysed. Results This subanalysis included 1011 patients (38% female, 66±11 years old, 64% paroxysmal atrial fibrillation [PAF]). ERATs were recorded in 178/1011 (18%) of patients (16% in PAF and 21% in persAF, p=0,021). Notably, ERAT patients were older (67,1±11,4 Vs 65,4±10,9, p=0,015) and had a higher median CHA2DS2-VASc Score (2,5 [IQR:1-4] Vs 2 [IQR:1-3]; p=0,019). The 35-mm catheter was more often used in ERAT patients (48/178(27%) Vs 148/833(18%) – p=0,005). At a median follow-up of 365 days (IQR 347-390), 100/178(56%) of patients with ERAT had documented late recurrence (LR), compared to only 147/833(18%) of patients in sinus rhythm throughout BP (p<0,001). Kaplan Meier estimates for overall freedom from AF/AT outside of the BP was 77% at one year for all patients. Patients with ERAT had a significantly lower freedom from AF/AT compared to patients with no ERAT (42% vs 84%, log-rank p<0,001). The absence of ERAT was associated with long-term success independent of the type of AF (41% Vs 88% in PAF, 43% vs 74% in persistent AF; p<0,001 for both). Among ERAT patients, no additional predictors for LR were identified. Conclusions In this large multicentre international registry, early recurrence of atrial tachyarrhythmia following PFA PVI were recorded in 18% of patients. ERAT was associated with late recurrences in the majority of cases, independent of AF type. The need for a blanking period following non thermal energy ablation for atrial fibrillation should be further questioned.

Cryoballoon ablation for atrial fibrillation in young adults: a propensity-score matching comparison with an older cohort

Abstract Background Cryoballoon ablation (CB-A) has proven to be a valid technology for achieving pulmonary vein isolation (PVI) in patients affected by symptomatic atrial fibrillation (AF). Data regarding CB-A in young adults are still scarce and mainly derived from studies performed without balancing comorbidities and echocardiographic parameters between the groups. The present study aimed to focus on the outcomes and complications of CB-A PVI in young adults (< 50 years) compared to a propensity score-matched population of older individuals, seeking also to understand the true role of "age" as potential risk factor for arrhythmia recurrences. Methods and results We retrospectively enrolled 172 consecutive patients aged < 50 years who underwent PVI employing the second-generation cryoballoon (CB-2). A 1:1 propensity score matching comparison with an older cohort of patients was performed and 290 patients (145 subjects aged < 50 years vs. 145 patients aged ≥ 50 years) were then selected. The mean age was 43.3 ± 4.9 years in the younger group and 64.7 ± 8.7 years in the control group (p < 0.001). After an overall median follow-up of 18 [12 - 29] months, the Kaplan-Meier curves showed a similar rate of freedom from arrhythmia relapses between the younger and the older cohorts (85.5% vs. 77.2% respectively, log-rank p = 0.31). The rate of major complications was low (2.8 %) and did not significantly differ between the groups, being 2.1% for the younger cohort and 3.5% for the older group (p = 0.50). Vascular complications and phrenic nerve palsy appeared to be the most common procedure-related adverse events, occurring in 8 (2.8%) patients. Arrhythmia recurrences during blanking period (ERAF) was found to be the only independent predictor of late AT/AF relapses. Conclusions Our propensity-score model demonstrates that CB-A PVI is equally safe and effective in young adults as it is in older individuals. Furthermore, our findings suggest that "age" itself does not appear to play a significant role in predicting recurrences after CB-A PVI. This result underscores the importance of controlling the modifiable risk factors (comorbidities) and emphasizes the value of early AF diagnosis and intervention.Survival Curve

Comparison of peri-device sealing and procedural outcome after LAA closure in patients with and without isolated left atrial appendage

Abstract Background Catheter-based electrical isolation of the left atrial appendage (LAA) is increasingly performed in patients with symptomatic atrial fibrillation (AF) not responding to pulmonary vein isolation (PVI). Since the electrically isolated LAA is known to be susceptible to thromboembolism, endovascular LAA occlusion (LAAO) is increasingly being used. Objective We performed a procedural and clinical outcome analysis over 12 months in patients receiving two different LAAO device systems and compared those with versus those without LAA isolation (LAAI). Methods Between 08/2021 and 10/2022 we enrolled 83 consecutive patients (median age 73.2 years; median CHA2DS2-VASc Score 3.0; 51 men [61%]) of whom 59 (71%) had LAAI and 24 (29%) no LAAI. All patients had a least one previous catheter ablation procedure of AF. LAAO was done 6 weeks after the last ablation procedure. The main indication for LAAO was the implementation of electrical LAAI. In the no-LAAI group, all patients had lost persistent LAAI. Implanted devices were Watchman FLXTM (n=30) and LAmbreTM (n=53). Pertinent procedural data, periprocedural complications, as well as peri-device leaks (PDL) at 45 days were assessed according to device type. The composite endpoints (death, TIA/stroke, device thrombus, bleeding) and the clinical impact after switch of anticoagulation therapy were assessed at 12 months follow-up. Results The distribution of LAAI/No LAAI were found in 21[70%]/9 patients treated with the Watchman device and in 38[72%]/15 patients treated with the LAmbre device (p=0.87). PDL on follow-up (f/u) TEE was observed in 13/54 LAAI patients (24%) and 10/23 No-LAAI patients (43%, p=0.089). Leak distribution (<3mm/3-5mm/>5mm/no leak) at f/u was different between LAAI groups (LAAI: 12/1/0/41; No LAAI: 5/4/1/13; p=0.027) but not between device types. The mechanisms of leaks according to device type are listed in Table 1. Procedural complications were observed in 6/59 LAAI patients and 0/24 No-LAAI patients (p=0.11). The composite endpoint of death, stroke, severe bleeding, device-related thrombus and thromboembolism was reached by a total of 2 patients (both LAAI with LAmbre device). In 9/13 LAAI-group patients (69%) with PDL (all <6 mm) the sealing effect was assumed to be incomplete with perfusion of the LAA. Post procedural anticoagulation therapy was switched after the control TEE from NOAC/VKA (8/1) to aspirin alone. None of these patients reached the composite endpoint after 12 months. Conclusions LAAO can be performed safely and efficaciously in patients with LAAI. Compared with patients without LAAI after LAAO, the occurrence of minor leaks, periprocedural complications, and composite endpoint events was not different between the two patient groups. Despite the presence of incomplete sealing with perfusion of LAA in the LAAI group, the switch in post-procedural anticoagulation seems to be safe regarding the composite endpoint after 12 months.Mechanism of PDL of the LAmbre DeviceMechanism of PDL between the LAAO types

Validation of the Castle HTx data in a real world scenario

Abstract Background Pulmonary vein isolation (PVI) is recommended in patients with symptomatic atrial fibrillation (AF) and reduced left ventricular ejection fraction (LVEF). Recently the Castle HTx (CHTx) trial showed a significant mortality reduction in end stage heart failure patients undergoing PVI in addition to optimized medical therapy (OMT) compared to OMT only. Aim Objective of this analysis is to validate results of Castle HTx study in a real world scenario. Methods All patients between September 2021 und September 2023 referred for PVI at our center with symptomatic AF und LVEF ≤35% were included in this retrospective analysis at the University Hospital Cologne. Results A total of 119 PVI in patients with LVEF≤35% were successfully performed (mean age 63.3±10.1 years, 96 patients (81%) male, 43 (36%) paroxysmal AF, 76 (64%) persistent AF) matching inclusion criteria used in CHTx. Cryo-PVI was used in 50 (42%), RF-PVI in 60 (50%) and PFA in 9 (8%) patients. Complete follow-up (FU) with a mean of 549.6±430.2 days was obtained in 108 patients, comparable to CHtx (540 days). During FU 11 patients (10%) died from any cause (CHTx 8 patients (8%)), 2 patients (2%) received a left ventricular assist device (CHTx 1 patient (1%)) and no patient had urgent heart transplantation (CHTx 1 patient (1%)). For 30 patients (28%) recurrence of AF was detected and 72% remained in sinus rhythm. In 6 patients (5%) post-procedural complications occurred: 5 inguinal hematoma, 1 decompensation. During FU LVEF was statistically significantly improved (EF initial 26.9±6.5%, EF FU (n=80) 37.1±12.8%, p<0.001) (CHTx EF initial 29.0±6.4%, EF FU (n=92) 37.2±9.1%). Conclusion The findings of the Castle HTx patients have been validated in a real-world setting. PVI for rhythm control in end stage heart failure patients is safe and highly effective. Our patient cohort, matched to the Castle HTx ablation group, showed freedom from AF rate of 72% after mean FU time of 550 days. Furthermore, LVEF was improved significantly in our cohort echoing the results from CHTx.

Multicenter retrospective evaluation of a patient-tailored electrogram-based ablation strategy using an artificial intelligence software in repeat atrial fibrillation ablation procedures

Abstract Background While pulmonary vein isolation (PVI) is the gold standard approach of treatment of atrial fibrillation (AF), the optimal strategy in case of AF recurrences for redo patients is not well established. Several studies described the usefulness of ablating in atrial regions exhibiting abnormal electrograms, i.e. spatio-temporal dispersion, during AF and an artificial intelligence (AI) electrograms (EGMs)-based software solution has been developed and validated to obtain real-time adjudications of multipolar electrograms in de novo patients. Purpose This study sought to evaluate the novel AI-EGMs-based software approach for redo-AF ablation procedures. Methods This study was a retrospective, multicentric, nonrandomized study. Patients with recurrent symptomatic AF were enrolled in 7 European centers. Redo ablation procedures were performed using the AI software and acute and long-term outcomes after ablation were evaluated. Results A total of 117 patients with refractory symptomatic AF admitted for redo procedure were included with 30% paroxysmal, 42% short-standing persistent and 28% long-standing persistent AF at the time of the redo procedure. During the index procedures, a previous PVI ablation was performed in all patients while additional ablation such as lines and EGM-based ablation was performed in 64 patients (55%). Out of 117 patients, 30 (26%) presented with structural heart disease, 61 (52%) with hypertension, 31 (26%) with a BMI >30, 16 (14%) a sleep apnea syndrome and 24 (20%) had an antiarrhythmic treatment at the time of the procedure. The average AF history was 6.54 ± 4.15 years with an average sustained duration equal to 25 ± 62 months. AI-EGMs-based AF ablation was performed in all patients and easily integrated in the physicians’ workflow during redo procedures. AF termination, i.e. AF regularization or sinus rhythm conversion, occurred in 82/117 patients (71%) with sinus rhythm conversion by ablation in 79/117 patients (68%). After a mean follow-up of 11 ± 5 months, 81% of patients were free from documented AF, with or without antiarrhythmic drugs (AADs) after one redo procedure and 60% of patients were free from any documented atrial arrhythmia, with or without AADs, after one redo procedure per patient. Furthermore, we observed that 77%, 84% and 82% of patients were free from documented AF with or without AADs in paroxysmal, short-standing and long-standing persistent AF patients respectively, and that 71%, 59% and 49% of patients were free from any documented atrial arrhythmia with or without AADs in paroxysmal, short-standing and long-standing persistent AF patients respectively. Conclusions This retrospective study reports that patient-tailored spatiotemporal dispersion ablation is a relevant and standardized approach for repeat AF ablation. This was obtained with an AI-EGMs-based software solution, which may be added to the operative workflow of redo AF procedures.

LINAC-Based STereotactic Arrhythmia Radioablation (STAR) for paroxysmal atrial fibrillation in elderly: a prospective phase II trial

Abstract Background and aims Stereotactic arrhythmia radioablation (STAR) is a novel therapeutic approach for cardiac arrhythmias. The aim of this trial is to investigate the feasibility of STAR for the treatment of paroxysmal atrial fibrillation (AF) in elderly patients. Method inclusion criteria were: age > 70 years, symptomatic AF, antiarrhythmic drugs failure or intolerance. All patients underwent to 4D cardiac Computed Tomography simulation. The clinical target volume was identified in the area around pulmonary veins (PV). STAR was performed with a total dose of 25 Gy (single fraction) delivered in 3 minutes. Results Twenty patients were enrolled and 18 underwent STAR. One patient withdrew informed consent before treatment and 1 patient was excluded due to unfavorable esophagus position. With a median follow-up (FU) of 16 months (range 12-23), no acute toxicity more than grade 3 was reported. Five patients had a grade 1 esophagitis 24 hours after STAR; eight patients had an asymptomatic grade 1 pericardial effusion, one patient had a torsade de pointes treated effectively by electrical cardioversion and subsequent cardiac ICD implantation. Most patients had a significant reduction in AF episodes. Five patients, due to arrhythmias recurrences after STAR, performed electrophysiological study documenting successful PV isolation. Finally, a significant improvement of quality of life was documented (48 ± 15 at enrollment vs 75 ± 15 at 12 months FU; p < 0.001). Conclusion The present phase II trial demonstrated the feasibility of STAR in paroxysmal AF elderly patients and its potential role in increasing the quality of life. Surely, more robust data are needed about safety and efficacy.

Severity of tricuspid regurgitation predicts risk of atrial fibrillation recurrence after pulmonary vein isolation

Abstract Background Atrioventricular valve regurgitation (AVVR) results in atrial remodeling, thus promoting the formation of a substrate for atrial fibrillation (AF). On the other hand, AF may cause functional AVVR by annular dilatation of the atria. In this vicious circle, the identification of the leading pathomechanism and consequently the optimization of treatment can be challenging. Purpose Our aim was to investigate whether the presence of significant AVVR and especially of tricuspid regurgitation (TR) affects the efficacy of catheter-based pulmonary vein isolation (PVI) for AF. Furthermore, we evaluated whether rhythm control for AF through PVI could lead to an improvement of AVVR severity. Finally we examined the effect of concomitant right atrial flutter on the arrhythmic outcome in patients with significant TR . Methods We enrolled patients undergoing first-time PVI for symptomatic AF. We compared the severity of AVVR at the time of the procedure as well as after 6 months, using transthoracic echocardiography. Moderate to severe AVVR was defined as significant. Moreover, we evaluated whether the presence of significant AVVR, at baseline and 6 months after the procedure, could serve as an independent predictor for AF recurrence. Results Out of 320 consecutive patients (mean age 66.3 ± 10 years, 61.6% male, 60% paroxysmal AF) , significant TR at baseline was documented in 13.1%, while significant mitral regurgitation (MR) in 10.9%. Six months after PVI, the proportion of patients with moderate to severe TR (13.1% to 7.2%; p<0.001) and MR (10.9% to 6.6%; p<0.001) decreased significantly. Compared to patients with post-interventional improvement of significant TR, right atrial (RA) dilatation at baseline was more pronounced in patients with persistent significant TR (RA area 20.2 ± 4.4 vs. 26.6 ± 8.3 cm2; p=0.002). The presence of significant TR, particularly without improvement during the follow-up, independently increased the risk of atrial fibrillation recurrences. Even after propensity-score matching, TR at baseline remained an independent risk predictor regarding recurrent atrial fibrillation (HR 2.2 [95% CI, 1.1 - 4.9]; p=0.045). Among patients with significant TR, those with documented right atrial flutter were at high risk for recurrence of atrial arrhythmia (HR 2.69 [95% CI, 1.0 – 6.9]; p=0.039), despite the additional ablation of the cavo-tricuspid isthmus. Significant MR was not associated with increased risk of atrial arrhythmias. Conclusion In patients with symptomatic AF undergoing PVI, the presence of moderate to severe TR, particularly without improvement 6 months after the procedure, was associated with a worse arrhythmic outcome. Further investigations to enhance the understanding of the underlying electrophysiological substrate and the need for tailored ablation strategies are warranted.TR as predictor for AF(propensity score)AVVR improvement after PVI

The new "olive strategy" for pulsed field ablation of atrial fibrillation: procedural data and early follow-up

Abstract Background Pulsed field ablation (PFA) is a new myocardial-specific ablation technology for atrial fibrillation (AF). Direct current electric energy is applied to cells and disrupts cell membranes by creating pores. Purpose The aim of this single-center study was to report procedural data and early recurrence of atrial tachyarrhythmia (ERAT) following a new PFA-based ablation strategy for pulmonary vein isolation (PVI). Methods Consecutive patients with symptomatic AF were enrolled to undergo PFA-PVI using the pentaspline catheter. A new ablation strategy was performed: In total 10 applications per pulmonary vein (PV) were delivered. In addition to the conventional four applications in flower- and four applications in basket-configuration, two applications were delivered in a smaller "olive"-configuration. ERAT was defined as any documented AF/atrial tachycardia (AT) lasting more than 30 seconds during a 90-days blanking period. Procedural and demographic data were analysed. Results 60 patients (37% female, age 67±12, 43% paroxysmal atrial fibrillation [PAF]) were included in this preliminary analysis. 239 PVs were identified, and all PVs could be isolated using solely the PFA device. All PVs were isolated with the first application. 40 applications per patient were delivered. No complications occurred. Procedure time was 30±11 min, fluoroscopy time was 6±3 min. Median follow-up time was 100 days. 20% of patients experienced an early recurrence after a median of 2 days (IQR 1-7.25; 92% AF, 8% AT). Kaplan Meier estimated freedom of AF/AT was 83.3 % at 3 months, 92.3% for PAF and 76.5% for persistent atrial fibrillation (p=0.11). Conclusions Our data show feasibility of a new ablation strategy with the pentaspline PFA-catheter. This study indicates high acute efficacy and safety. 83.3% of patients are free of AF/AT at 3 months. Longer follow-up times are needed to assess the clinical outcome and will be available at the time of presentation.

Oral flecainide therapy and myocardial pacing: preliminary data from a prospective multicenter registry

Abstract Background Antiarrhythmic drugs, class I are widely used for prevention of atrial fibrillation recurrence. However, previous studies found that these drugs could affect pacing thresholds among pacemaker recipients. Aim of the study: evaluate short -term effect on myocardial pacing following therapy with oral flecainide (200 mg/daily). Methods 45 consecutive pacemaker recipients were prospectively enrolled in a multicenter registry. These patients had preserved left ventricular ejection fraction, a dual chamber pacemaker with symptomatic sustained high-rate atrial fibrillation episodes and stable output atrial and ventricular thresholds. Patients were followed with ambulatory and/or remote monitoring. Results mean age was 74±1 years, 48% pts were male and AF burden was 8±16%. Pacemaker implantation was performed 3.9±0.3 year before study enrollment. Three (6%) out of 45 patients were excluded due to drug sided effects including dyspnea (n=1), diplopia (n=1) and toxicity during acute renal insufficiency (n=1). Flecainide treatment was associated with a significant reduction of atrial fibrillation burden (from 8±16% to 5±12%, p<0.01). At 30 days follow-up since Flecainide starting therapy both atrial and ventricular sensing significantly decreased (3.6 ± 2.2 vs 3.4 ± 2.1mV p=0.01; 12.5±6.6 vs 11.8±6.3 mV p=0.01), while there was a slight increase of both atrial and ventricular capture thresholds (0.77±0.61V@0.4ms vs 0.80±0.42V@0.4ms p=0.01; 0.80±0.53V @0.4ms vs 0.83±0.33V @0.4ms p=0.01). No patient required pacemaker parameters reprogramming. Conclusions oral flecainide therapy among pacemaker recipients at 30 days follow-up seems to be safe and do not affect device function. Further studies with additional follow-up data are warranted.

Pulmonary vein isolation with the radiofrequency balloon catheter: long-term results and predictors of ablation success

Abstract Background The novel multielectrode radiofrequency balloon catheter (RFB) has been demonstrated to achieve safe and effective pulmonary vein isolation (PVI). However, data on long-term ablation outcomes is lacking. Purpose This single-centre study aimed to evaluate the efficacy of the RFB beyond 1-year follow-up and define predictors of arrhythmia recurrence. Methods All consecutive patients with symptomatic paroxysmal atrial fibrillation (AF) undergoing first-time PVI with the RFB between January 2021 and November 2022 were prospectively included. Post-ablation remapping was systematically employed to confirm PVI at the end of the procedure. Procedural failure was defined as any atrial tachyarrhythmias (ATas) lasting >30 s occurring during the follow-up after a 3-month blanking period (BP). Patient characteristics, procedural parameters, and ATas recurrence during BP were analysed with respect to ablation outcome. Results A total of 120 consecutive patients (50 female, 42%; mean age 65±12 years) were enrolled. After a mean follow-up of 16.1±7.9 months, ATas recurrence occurred in 30 patients (25%). ATas were adjudicated as AF in 25 patients (83.3%) and as atrial tachycardia/atrial flutter in 5 patients (16.7%). The mean time from the index procedure to ATas recurrence was 203±130 days. A redo procedure was performed in 17 patients (56.7%) and at least one PV reconnection was observed in 12 patients (70.6%). Patients with ATas recurrence presented higher values of body mass index (31.0 ±5.7 vs. 28.1±4.9 kg/m2, p=0.048), larger left atria (43±11 vs. 35±9 ml/m2, p=0.003), and increased rates of ATas recurrence during the BP (53.3% vs. 2.2 %, p<0.001) compared to patients with persistent sinus rhythm. At multivariable Cox regression analysis, left atrial end-systolic volume index and ATas recurrence during the BP were independently associated with procedural failure (HR 1.05, 95%CI 1.00-1.11, p=0.048 and HR 23.88, 95%CI 7.71-73.99, p<0.001, respectively). Conclusion At 16 months follow-up, PVI with the RFB resulted in freedom from arrhythmia relapse in 75% of patients. Left atrial end-systolic volume index and ATas recurrence during the BP were independent predictors of arrhythmia recurrence.ATas-free survivalPredictors of ATas recurrence

An economic evaluation of first-line cryoballoon ablation versus antiarrhythmic drug therapy for the treatment of paroxysmal atrial fibrillation from a Danish healthcare perspective

Abstract Background As demonstrated in three randomized clinical trials (RCTs), initial rhythm control with first-line pulmonary vein isolation (PVI) using cryoballoon ablation decreases atrial arrhythmia recurrence compared to antiarrhythmic drug (AAD) therapy in patients with symptomatic paroxysmal atrial fibrillation (PAF). Purpose To assess the cost-effectiveness of first-line cryoablation versus first-line AADs in a Danish healthcare setting. Methods Data from 703 participants with symptomatic PAF enrolled into Cryo-FIRST, STOP AF First and EARLY-AF RCTs were used to estimate risk equations (rate of ablation, AF recurrence and resolution, AF-related hospital attendance in addition to health-related quality-of-life (HRQoL) utilities). These were then incorporated into a cost-effectiveness model (CEM) . The Danish cost data was derived from published Danish literature, DRG tariffs and pharmaceutical list prices in Denmark. Where parameters could not be derived, inputs were sourced from published literature or expert opinion. The CEM consisted of a decision tree (one-year time horizon) and a Markov model (three-month cycle length) hybrid, with a lifetime (40 years) time horizon. The CEM is from the perspective of the Danish healthcare system. Health benefits were expressed in quality-adjusted life-years (QALYs), and all costs and benefits were discounted at 3%. As there is no official cost-effectiveness threshold in Denmark, the UK threshold of £20,000 (~€23,200) was assumed. Input uncertainty within the CEM was explored using probabilistic sensitivity analysis. The results presented include data from the initial 12-week blanking period for all studies. Results The three-monthly rate of AF symptom recurrence had a reduction, on average, of 46.7% (p<0.001) in those treated with cryoablation. In addition, the cryoablation arm had a 72.8% (p<0.001) reduction in the monthly rate of receiving an ablation following initial treatment. The average cryoablation patient was also associated with a 4.3% (p=0.025) increase in their HRQoL. Finally, there was no difference in the rate of AF symptom resolution in those who failed initial treatment. Base case results per patient are presented in Table 1. Cryoablation was shown to be dominant when compared to AADs (0.159 more QALYs and €2,519 less costly), with a 99.96% probability of being cost-effective at a willingness-to-pay threshold of ~€23,200 per QALY gained. Individuals in both arms of the model were also expected to receive ~1.2 ablations over a lifetime horizon. Nonetheless, there was a 45% relative reduction in time spent in symptomatic AF states for individuals who were initially treated with cryoablation. Scenario analysis results are presented in Table 2. Cryoablation remained cost-effective over AADs in all scenarios conducted. Conclusions Initial rhythm control with cryoballoon ablation is cost-effective (dominant) when compared to AADs in the Danish healthcare system.Table 1:Key results (per patient)Table 2.Deterministic scenario analysis

Long-term recurrence-free survival following second-generation cryoballoon ablation for persistent atrial fibrillation: role of the autonomic nervous system

Abstract Background The cardiac autonomic nervous system (ANS) plays a pivotal role in the regulation of atrial fibrillation (AF). Cryoballon (CB)-guided pulmonary vein isolation (PVI) is an established treatment for AF. Purpose In our present study we evaluated the impact of vagal reactions (VRs), as a surrogate parameter for ANS modulation, on the long-term outcome of CB-ablation in patients with persistent AF (PERS AF). Methods Data from consecutive PERS AF patients undergoing primary CB-guided PVI for symptomatic drug refractory AF between 2013-2023 were analysed. VRs were defined as bradycardia < 40 beats/min, asystole or higher-degree atrioventricular block. Long-term follow-up data were assessed. AF-recurrence was defined as AF lasting > 30 seconds beyond a 3-month blanking period. Results A total of 250 consecutive patients (mean age 63.9±10.0 years, 30% female) were included. VRs were recorded in 61 patients (24%, mean age 64.2±13.0 years, 30% female). The mean follow-up duration amounted to 84±14 months. Within this observation period 101 patients (40%) developed AF-recurrence. Re-ablation procedures were performed in 61 patients (60%). Patients with PVI-associated VRs presented with a significantly higher estimated AF-free survival rate (log-rank p-value < 0.001) (Figure 1) and a significantly longer median AF-free survival time (75 months, interquartile range (IR) 63-92 months) compared to those without (69 months, IR 13-79 months) (p=0.002). Beyond that Kaplan-Meier plot analyses revealed significant gender differences (Figure 1). Multivariate cox regression analyses confirmed VRs (Confidence interval (CI) 0.294-0.838, Hazard Ratio (HR) 0.497, p=0.009) and male gender (CI 0.352-0.781, HR, 524, p=0.001) as independent predictors (IPs) for AF-free-survival. Conclusion CB-ablation procedure associated VRs and male gender seem to be associated with a favorable long-term outcome in PERS AF. Further studies are warranted to verify our observations.Kaplan Meier plot on long-term AF-free s

Predictors of neuromodulation during single-shot thermal atrial fibrillation ablation: a computed tomography imaging analysis

Abstract Background Ganglionated plexi (GPs) are part of the cardiac autonomic nervous system (CANS), which play an important role in the induction and maintenance of atrial fibrillation (AF). Because of the anatomic proximity of the pulmonary veins with GPs, pulmonary vein isolation (PVI) using thermal (radiofrequency (RF) or cryo) ablation, has been shown to concomitantly affect the GPs, as suggested by increased heart rate (HR) after ablation. Right superior pulmonary vein (RSPV) isolation has been reported to have the most evident inhibitory responses to the CANS via modulation of the anterior right ganglionated plexus. Nonetheless, there are also cases with little to no effect on neuromodulation post-ablation. Purpose To assess the clinical and anatomical predictors of thermal ablation-induced CANS changes, as assessed via variations in resting HR post-ablation. Methods We retrospectively analyzed consecutive patients with symptomatic paroxysmal AF who underwent first-time PVI by cryoballoon (CB) or RF balloon (RFB) between January 2022 to November 2022. Patients who were not in sinus rhythm, had cardiac implantable electronic devices, or did not have a contrast-enhanced computed tomography before the ablation were excluded. Pre-ablation and 24-hour post-ablation ECGs in sinus rhythm were collected and analyzed to assess HR. Results A total of 83 patients (CB group, n = 43 vs RFB group, n = 40) were included in the analysis. Baseline patients’ characteristics were similar between the two groups (Table 1). A significant HR increase (ΔHR ≥ 15 bpm) at 24h post-ablation occurred in 31 patients [CB group 16 (52 %), RFB group 15 (48 %)]. Predictors of increased HR were the distance between superior vena cava (SVC) and RSPV (OR 0.51, CI 0.35 - 0.75, p value < 0.01) and age (OR 0.94, CI 0.89 - 0.99, p value < 0.01) (Table 2). Conclusions Single-shot thermal PVI influences the CANS, especially in patients with a shorter SVC - RSPV distance and in younger patients.Table 1Table 2

Long-term follow-up of pulmonary vein cryoballoon isolation using a double 120s vs single 240s standard freeze protocol

Abstract Background Recently, pulmonary vein isolation (PVI) using a double 120s freeze protocol has demonstrated to be non-inferior to a single 240s protocol despite a potentially increased procedural safety. Main advantages of a double 120s protocol are a reduction of phrenic nerve injury and an increase of the mean minimal esophageal temperature during the procedure. Methods We performed a long-term follow-up comparison between groups of patients with history of symptomatic atrial fibrillation undergoing PVI with second generation cryoballoon (CB) between 2019 and 2020. Our usual energy dosing protocol was modified including 2 times 120 seconds applications instead of a single 240 seconds application. Of A total of 160 consecutive patients, 80 were treated with double 120s (CB120) and 80 with single 240s (CB240) freeze protocol. 107 patients were, successfully, followed-up. The primary end-point was freedom from atrial tachyarrhythmia. Results Before PVI a total of 11/52 patients (21%) had persistent AF and 41/52 (79%) had paroxysmal AF in the CB120 group; a total of 20/55 patients (36%) had persistent AF and 35/55 (64%) had paroxysmal AF in the CB240 group. On a mean follow-up time of 17 months, freedom from atrial tachyarrhythmia was 63% in those patients undergoing CB240 and 74% with CB120 (log-rank P=0.255). Conclusions The double 120s freeze protocol is not-inferior as compared to the standard 240s in terms of freedom from recurrences on a long term follow-up, but with a more favorable procedural safety profile.

Assessing the impact of 3D imaging assistance on efficiency and safety in atrial fibrillation cryoablation

Abstract Introduction Pulmonary vein (PV) isolation is a cornerstone therapy for symptomatic atrial fibrillation (AF). Current 3D-navigation technologies used with radiofrequency (RF) ablation allow drastic reduction of X-ray exposure and better anatomical characterization improving acute and long-term procedural results. Cryoballoon ablation (CA) procedures typically rely on conventional fluoroscopy, resulting in significant X-ray exposure. Although contemporary fluoroscopy technologies allow for potential 3D imaging integration, their specific utility in improving procedural guidance during CA remains undefined. Method Using semi-automatic segmentation obtained from pre-procedural cardiac computed tomography, 3D segmentations of the left atrium, including PV, spine and primary bronchi walls were fused on the real-time fluoroscopy acquisitions in three standard positions (AP, LAO, RAO), acquired at the beginning of the procedure (Figure1). We compared procedural characteristics of CA performed with 3D-fusion imaging to conventional fluoroscopy-guided procedures. Results Thirty-six patients (aged 60±13 yo, 85% male) with paroxysmal AF treated with CA were included in the study: 18 in the control group (conventional fluoroscopy) and 18 in the 3D-assisted group. Acute PV isolation was achieved in all patients. The 3D-assisted CA was associated with significantly shorter procedure duration (mean 97.8±15.5 vs 82.1±16.1 min, p=0.0048); left-sided dwelling time (mean 77±15.2 vs 65.1±14.4 min, p=0.0351); and lower X-ray energy delivered to the patient (Dose Area product) with mean 661±373.1 vs 378.1±316.8 cGy*cm2 (p=0.013). Interestingly, we found that 72.2% of 3D guided procedures were done in less than 90min, while 77.8% of conventional cases required more than 90min to be completed (Figure 2D). Conclusion 3D-fusion imaging integration is feasible and allows for an exact PV anatomy depiction on fluoroscopy. Our data illustrates that it might significantly improve CA efficiency (shorter procedure duration) and safety (lower X-ray exposure and left-sided dwelling time). Our approach could also impact long-term results since it might reduce the likeability of missing intermediate PVs. Further research is needed to evaluate the incremental value of 3D imaging in long term efficacy.Figure 1Figure 2

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.

Treatmen of atrial fibrillation with cryoballoon pulmonary vein isolation - results of a 5-year follow-up

Abstract Background Atrial fibrillation is the most common arrhythmia in the general population and cryoballoon ablation is gradually becoming a first-line treatment. However, data regarding long-term outcomes after this procedure are still lacking. Aim The goal was to show the results of a long-term follow-up following the cryoballoon pulmonary vein isolation in patients with atrial fibrillation (AF). Methods A total of 126 patients were included in the study of which 77.0% had paroxysmal atrial fibrillation (PAF). Successful treatment outcome was defined as AF recurrence-free survival with stabile sinus rhythm during 5 years after the procedure. A treatment failure was defined as symptomatic AF recurrence with ECG verification (12 lead ECG or AF lasting >30s by Holter EKG). The patients on antiarrhythmic therapy and those who underwent a redo pulmonary vein isolation procedure were also included. Results Following cryoballoon pulmonary vein isolation in a 5-year period 52.4% of patients were in stable sinus rhythm without AF recurrence. With redo pulmonary vein procedures a total of 61.9% of patients were without AF recurrence. Together with antiarrhythmic drugs 57.9% of patients were in sinus rhythm without AF recurrence in a 5-year period. With redo pulmonary vein isolation and antiarrhythmic drugs a total of 73.8% of patients were without AF recurrence. There was a statistically significant difference regarding AF recurrence between patients who underwent redo pulmonary vein isolation and those who did not (p=0.006). In patients with PAF, 62.9% remained without AF recurrence, and 79.4% underwent a redo procedure. In patients with persistent atrial fibrillation (PersAF), 41.4% were without AF recurrence, and 55.1% underwent a redo procedure. The difference between PAF and PersAF was statistically significant (p=0.009). Conclusion Data from our center show good long-term results of cryoballoon pulmonary vein isolation in patients with atrial fibrillation. The procedure is especially successful in patients with PAF.1 The use of redo procedures is justified as it increases the long-term success rate.