Non-pulmonary Vein Research Articles

Atrial pace mapping with automatic intracardiac pattern matching for non-pulmonary vein trigger ablation: accuracy and feasibility

Abstract Atrial pace mapping (APM) is an alternative method to localize non-pulmonary vein (non-PV) triggers of atrial fibrillation(AF) that are otherwise not eligible for activation mapping due to their instability. The technique applies pattern matching of p-waves and intracardiac signals of atrial trigger and pacing from the site of the suspected origin. A new automated algorithm for intracardiac (IC) pattern matching was recently introduced into the 3D mapping system using the unipolar signal of the reference catheter. The study aims to assess the accuracy and feasibility of APM using IC-pattern matching for localizing non-PV triggers. Methods We assessed the precision of APM using a single chamber and double chamber reference in 20 patients who underwent index pulmonary vein isolation. APM was performed at the anterior and posterior wall of the left atrium (LApost, Laant) and the posterior and lateral wall of the right atrium (Rapost, Ralat). The first pacing point was declared as the origin. The IC-pattern matching algorithm was applied to calculate the similarity of the IC-pattern of the origin to the paced IC-pattern across various distances. The distribution of IC-pattern similarities was analyzed in the Python environment. The feasibility of APM was tested in patients who underwent REDO ablation of AF if all PVs were isolated and no low-voltage substrate was detected. The induction protocol for non-PV triggers included programmed and burst atrial pacing, high-dose isoproterenol, and adenosine infusion. If the IC pattern of the trigger was reproducible, the IC pattern matching was conducted. Ablation was performed at the site of the best IC-pattern matching. Results Atrial PM with IC-pattern matching and a single referent catheter showed lower precision in the RA lateral region (the median[Q1; Q3 ]area of 5% best matching score 1.48 [0.76; 2.01], 0.62[0.15; 1.06], 0.6[0.38; 1.19] and 5.68[2.89; 11.1] cm2 for LApost, LAant, RApost, RAlat accordingly, p = 0.0316). IC-pattern matching with double referent catheter showed high precision at all four anatomical regions (the median [Q1; Q3] area of 5% best matching score 0.126 [0.0879; 0.356], 0.486 [0.205; 0.717], 0.269 [0.198; 0.719], and 0.257 [0.0740; 0.572] cm2 for LApost, LAant, RApost, RAlat accordingly, Fig. 1). Seven out of 37 patients referred to REDO ablation had all PV isolated and absence of low-voltage substrate. In 3 of them, sustained tachycardias (AVNRT, focal atrial tachycardia and typical atrial flutter) were induced, mapped, and ablated. Non-sustained FAT from the RA posterior wall and PAC in the RA septum were induced under the high-dose isoproterenol infusion in two patients. Atrial pace mapping with double chamber referent and successful ablation of these non-PV triggers were performed (Fig.2). Conclusion The atrial pace mapping of non-PV triggers employing the automatic intracardiac pace mapping algorithm is feasible with high accuracy if a double-chamber referent is used.Accuracy of atrial pace mappingNon-PV trigger pace mapping

Prevalance of incessant form of atrial fibrillation by superior vena cava (svc) firing:simplified svc and sinus node mapping(sss map) to avoid sinus node injury

Abstract Background The superior vena cava (SVC) is known as a major source of atrial fibrillation(AF), non-pulmonary vein AF foci (NPVAF). In some cases, an incessant form of AF (iAF) by SVC firing prevents obtaining the sinus node location, and anatomical SVC isolation has a risk of sinus node injury (SNI). Objective This study was aimed to explore the frequency of iAF by SVC firing and the efficacy of the simplified mapping strategy to avoid SNI. Methods Consecutive AF ablation procedures in the 3 centers were retrospectively investigated including the NPVAF prevalence. Simplified SVC/SN mapping (SSS-map: Obtaining the top-end of the SVC potential and >4points with 5-10mm spacing in the upper lateral side of the right atria (RA) for roughly locating the earliest activation site in sinus rhythm) was performed before PV isolation in the last 138 patients. In case of the initial rhythm at the procedure was atrial fibrillation, cardioversion was performed for obtaining the SSS-map. In the cases in which the high-density mapping catheters were available, the high-density activation maps of the RA in sinus rhythm were obtained to investigate the dislocation of the earliest activation site of the SSS map from the SN location. When SVC isolation was required due to iAF, SVC isolation line was designed based on the location of the top-end of the SVC potential during AF and ablative linear lesions were created to keep the distance of 5-10 mm above the second earliest activation site. Results A total of 1160 procedures in 1089 patients (male: 736[63.4%], age: 69.9, paroxysmal AF: 544[49.9%], first session: 997[85.9%]) was investigated. Prevalence of NPVAF was revealed in 160 of the all procedures (13.7%) (the SVC: 64, the posterior wall of the left atria: 24, the coronary sinus: 19, and others: 53). 16 of 160 NPVAFs (10.0%) developed to iAF by SVC firing. The SSS-map was successfully obtained in all of the last 138 patients (Initial rhythm at the procedure: AF 43.7%, Mapping time: 1.3±0.6 min, number of obtained points: 8.4±1.3). In 21 patients in which the high-density RA map was obtained, the SN dislocation distance was 5.1±2.2mm between the SSS map and the high-density RA map. Five of 138 developed to iAF by SVC firing, and SVC isolation based on the SSS-map was successfully achieved without SNI in the cases. Conclusion This study indicated iAF driven by SVC firing after PV isolation occurred in certain number of patients. The SSS-map before PV isolation was practical and showed the potential to be the mapping strategy avoid the SN injury in such cases.

Clinical relevance of left atrial structural remodeling and non-pulmonary vein foci in atrial fibrillation.

The mechanistic role of left atrial (LA) structural remodeling as a non-pulmonary vein (PV) trigger in the initiation of atrial fibrillation (AF) remains uncertain. This study is aimed at prospectively evaluating the association between non-PV triggers and LA structural remodeling. A total of 517 patients undergoing catheter ablation for AF were included. After PV isolation, a standardized protocol was implemented to reveal non-PV triggers, which included burst pacing into AF followed by cardioversion during isoproterenol infusion. If pacing-induced atrial tachycardia (AT) was observed, mapping and catheter ablation were performed. The mean percentage of LA low-voltage area (LVA) < 0.5mV incrementally increased during right atrial pacing among the no induction (n = 470), AF (n = 21), and AT (n = 26) groups (2.6 ± 5.7%, 5.5 ± 6.4%, and 18.0 ± 21.5%, respectively; P < 0.001). In the AF induction group, non-PV foci originated from the left atrium in 13 of 25 foci (52%), and 8 of 13 LA non-PV foci (62%) were located in the septal region. All except 1 focus originated from the non-LVA < 0.5mV (8%), but 8 of the 13 LA foci originated from the LVA < 1.0mV (62%). There were no differences in AF recurrence among the groups (log-rank, P = 0.160). The majority of non-PV foci in the LA originated outside regions with advanced structural remodeling, thus suggesting the limited effectiveness of adjunctive ablation guided by the LVA < 0.5mV during sinus rhythm in eliminating non-PV triggers.

Ablation Strategies for Persistent Atrial Fibrillation: Beyond the Pulmonary Veins.

Despite advances in ablative therapies, outcomes remain less favorable for persistent atrial fibrillation often due to presence of non-pulmonary vein triggers and abnormal atrial substrates. This review highlights advances in ablation technologies and notable scientific literature on clinical outcomes associated with pursuing adjunctive ablation targets and substrate modification during persistent atrial fibrillation ablation, while also highlighting notable future directions.

Usefulness of empiric superior vena cava isolation in paroxysmal atrial fibrillation ablation: a meta-analysis of randomized clinical trials.

The long-term success rate of pulmonary vein isolation (PVI) is suboptimal due to the presence of non-pulmonary vein (PV) foci that can trigger atrial fibrillation (AF) in up to 11%. Among non-PV triggers, the superior vena cava (SVC) is a major site of origin of ectopic beats initiating AF. To compare data from randomized controlled trials (RCTs) assessing PVI + empiric SVC isolation (SVCI) versus PVI alone in terms of AF recurrence, procedure-related complications, and fluoroscopic and procedural times. A search of online scientific libraries (from inception to April 1, 2024) was performed. Four RCTs were considered eligible for the meta-analysis totaling 600 patients of whom 287 receiving PVI + SVCI and 313 receiving PVI alone. In the overall population, SVCI + PVI was associated with a non-significant reduction of AF recurrence at follow-up (0.66 [0.43;1.00], p = 0.05, I2 0%). In patients with paroxysmal AF (PAF), a significant reduction of AF recurrence was related to SVCI + PVI (11.7%) as compared to PVI alone (19.9%) (0.54 [0.32;0.92], p = 0.02, I2 0%). No statistical differences were found among the groups in terms of fluoroscopic (3.31 [- 0.8;7.41], p = 0.11, I2 = 91%), procedural times (5.69 [- 9.78;21.16], p = 0.47, I2 = 81%), and complications (1.06 [0.33;3.44], p = 0.92, I2 = 0%). The addition of SVCI to PVI in patients in PAF is associated with a significant lower rate of AF recurrence at follow-up, without increasing complication rates and procedural and fluoroscopy times.

Feasibility of Auto-Quantified Epicardial Adipose Tissue in Predicting Atrial Fibrillation Recurrence After Catheter Ablation.

The aim of this study was to build an auto-segmented artificial intelligence model of the atria and epicardial adipose tissue (EAT) on computed tomography (CT) images, and examine the prognostic significance of auto-quantified left atrium (LA) and EAT volumes for AF.Methods and Results: This retrospective study included 334 patients with AF who were referred for catheter ablation (CA) between 2015 and 2017. Atria and EAT volumes were auto-quantified using a pre-trained 3-dimensional (3D) U-Net model from pre-ablation CT images. After adjusting for factors associated with AF, Cox regression analysis was used to examine predictors of AF recurrence. The mean (±SD) age of patients was 56±11 years; 251 (75%) were men, and 79 (24%) had non-paroxysmal AF. Over 2 years of follow-up, 139 (42%) patients experienced recurrence. Diabetes, non-paroxysmal AF, non-pulmonary vein triggers, mitral line ablation, and larger LA, right atrium, and EAT volume indices were linked to increased hazards of AF recurrence. After multivariate adjustment, non-paroxysmal AF (hazard ratio [HR] 0.6; 95% confidence interval [CI] 0.4-0.8; P=0.003) and larger LA-EAT volume index (HR 1.1; 95% CI 1.0-1.2; P=0.009) remained independent predictors of AF recurrence. LA-EAT volume measured using the auto-quantified 3D U-Net model is feasible for predicting AF recurrence after CA, regardless of AF type.

Utility of noninvasive electrocardiographic imaging in the localization of nonpulmonary vein triggers of atrial fibrillation determined by pacing common trigger sites.

Identifying the origin of nonpulmonary vein atrial fibrillation (AF) triggers (NPVTs) after pulmonary vein isolation (PVI) can be challenging. We aimed to determine if noninvasive electrocardiographic imaging (ECGi) could localize pacing from common NPVT sites. ECGi combines measured body surface potentials with heart-torso geometry acquired from computed tomography (CT) to generate an activation map. In 12 patients with AF undergoing first time ablation, the ECGi vest was fitted for preprocedural CT scan and worn during the procedure. After PVI, we performed steady-state pacing from 15 typical anatomic NPVT sites at a cycle length of 700-800 ms. We co-registered the invasive anatomic map with the CT-based ECGi epicardial activation map to compare ECGi predicted to true pacing origin. In the study cohort (67% male, 58% persistent AF, and 67% with left atrial dilation), 148 (82%) pacing sites had both capture and adequate anatomy acquired from the three-dimensional mapping system to co-register with ECGi activation map. Median distance between true pacing sites and point of earliest epicardial activation derived from the ECGi maps for all sites was 17 mm (interquartile range, 10-22 mm). Assuming paced sites treated as regions with a radius of 2.5 cm, the earliest activation site on ECGi map falls within the region with 94% accuracy. ECGi can approximate the origin of paced beats from common NPVT sites to within a median distance of 17 mm. A rapidly identified region may then be the focus of more detailed catheter-based mapping techniques to facilitate successful localization and ablation of NPVTs.

A validation study of the accuracy of the atrial pace map assessed with intracardiac pattern matching: Potential utility of non-pulmonary vein mapping.

Identification of infrequent nonpulmonary vein trigger premature atrial contractions (PACs) is challenging. We hypothesized that pace mapping (PM) assessed by correlation scores calculated by an intracardiac pattern matching (ICPM) module was useful for locating PAC origins, and conducted a validation study to assess the accuracy of ICPM-guided PM. Analyzed were 30 patients with atrial fibrillation. After pulmonary vein isolation, atrial pacing was performed at one or two of four sites on the anterior and posterior aspects of the left atrium (LA, n=10/10), LA septum (n=10), and lateral RA (n=10), which was arbitrarily determined as PAC. The intracardiac activation obtained from each pacing was set as an ICPM reference consisting of six CS unipolar electrograms (CS group) or six CS unipolar electrograms and four RA electrograms (CS-RA group). The PM was performed at 193±107 sites for each reference pacing site. All reference pacing sites corresponded to sites where the maximal ICPM correlation score was obtained. Sites with a correlation score ≥98% were rarely obtained in the CS-RA than CS group (33%vs. 55%, P=.04), but those ≥95% were similarly obtained between the two groups (93%vs. 88%, P=.71), and those ≥90% were obtained in all. The surface areas with correlation scores ≥98% (0[0,10] vs. 10[0,35] mm2, P=.02), ≥95% (10[10,30] vs. 50[10,180] mm2, P=.002) and ≥90% (60[30,100] vs. 170[100,560] mm2, P=.0002) were smaller in the CS-RA than CS group. ICPM-guided PM was useful for identifying the reference pacing sites. Combined use of RA and CS electrograms may improve the mapping quality.

Safety and efficacy of very high-power short ablation in superior vena cava isolation in patients with atrial fibrillation

Abstract Backgrounds The superior vena cava (SVC) plays an important role in non-pulmonary vein (PV) foci to trigger atrial fibrillation (AF) and thus are occasionally isolated. A major complication in SVC isolation is phrenic nerve injury, and a shallower ablation depth might be less likely to cause complications. Recently, very high power short ablation (vHPSD) has been demonstrated to be effective in PV isolation. On the other hand, vHPSD has been reported to have shallower depth than the low-power ablation strategies, suggesting concerns about insufficient ablation in thicker myocardial sites. The vHPSD might be effective and safe in SVC isolation thinner than myocardium, however, the details were not elucidated. Purpose This study was aimed to examine the safety and efficacy of vHPSD strategy in SVC isolation, compared retrospectively with low power ablation strategies. Methods Patients with AF who were undergoing first-time SVC isolation were included. An activation map was performed from the SVC to the right atrium during sinus rhythm, and a circumferential isolation line was designed by the CARTO system at a height of 1.5cm above the earliest site. The site and extent of capture of the phrenic nerve by pacing on the circumferentially designed ablation line were recorded. The first step was to perform circumferential ablation except for the sites where the phrenic nerve was captured. If the SVC isolation was completed, the procedure was completed. If the isolation was inadequate, the sites of capture of the phrenic nerve were also ablated. Two groups of patients were analyzed: those performing vHPSD (n=27, vHPSD group) with a power of 90 watts for 3 seconds or those using lower-power (n=20, LP group) limited to 20-40 watts. Results Forty-seven patients who underwent the initial SVC isolation were evaluated. We analyzed all 351 points in the vHPSD group and all 364 points in the LP group with ablation of SVC. No differences were found in the distance of the SVC circumference on the isolation line (vHPSD: 71±10 vs. LPLD: 71±11mm, p=0.95) or the extent of phrenic nerve capture (12±7 vs. 12±9mm, p=0.82). All patients in the vHPSD group were successfully isolated first-pass; the first-pass isolation rate tended to be higher than in the LP group (100% vs. 85%, p=0.07). Differences were observed in temperature rise (49±4 vs. 28±4 degrees, p&amp;lt;0.001) and impedance drop (12±4 vs. 7±5Ω, p&amp;lt;0.001), although there were no differences in the contact force (15±8 vs. 15±7g, p= 0.73). The vHPSD group achieved SVC isolation with a shorter procedure time (9±4 vs. 17±5 min, p&amp;lt;0.001) and fewer ablation points (13±4 vs. 18±4, p&amp;lt;0.001) compared to the LP group. In the vHPSD cases, ATP was administered after isolation, but no dormant conduction was observed. Only in one case in the LP group, transient phrenic nerve injury was observed. Conclusion The vHPSD for SVC isolation might be safe and result in shorter procedure time and fewer ablation points.

Charge-density mapping to evaluate non-pulmonary vein substrate in patients with paroxysmal atrial fibrillation: the ACUPRED study

Abstract Background/introduction Pulmonary veins (PV) electrical isolation (PVI) is the main ablation strategy for the treatment of paroxysmal atrial fibrillation (AF), since the description of PV triggers. However, non-PV substrate and triggers in AF are not a negligible clinical issue. Indeed, in up to 22% of patients with AF recurrence after PVI, all PV are found isolated. Non-PV triggers can be demonstrated in up to 10-15% of non-selected patients at first AF ablation and non-PV substrate has been related to functional slow conduction and fibrosis also in paroxysmal AF. Purpose The aim of this study is to evaluate non-PV substrate (slow conduction) and triggers with charge-density (CD) mapping in patients with paroxysmal AF. Methods All patients, were prospectively enrolled in 2023. Inclusion criteria for the study were: 1) paroxysmal AF patients undergoing PVI procedure with a single-shot device and 2) CD mapping pre- and post- PVI. CD mapping was performed during CS proximal pacing at cycle length (CL) 600 ms and CS proximal pacing at CL 300 ms, pre- and post- PVI. Conduction velocity (CV) magnitude (in cm/s) and vector (direction and sense) were calculated offline for each CD map for all anatomical vertices. Reduction map was defined as the map of CV magnitude difference between CL 600 ms and CL 300 ms, Figure 1. Refraction map was defined as the map of CV direction difference between CL 600 ms and CL 300 ms, Figure 1. Non-PV substrate was defined at pre-PVI maps as: 1) slow conduction (&amp;lt;30 cm/s) at CL 600 ms or CL 300 ms, or 2) difference in CV magnitude (&amp;gt;25 cm/s) at reduction map, a marker of functional slow conduction (induced by fast pacing), or 3) difference in CV direction more than 90° between two neighboring vertices at refraction map, a marker of anisotropy, Figure 1. Non-PV triggers were defined as non-PV premature atrial contractions &amp;gt;10/min or inducing AF. Results A total of 43 patients (60.6 ± 11.2 years, 74.4% males) with paroxysmal AF undergoing first procedure PVI were analyzed. Non-PV substrate was found in 13 patients (30.2%). Non-PV triggers were found in 3 patients (6.9%), including one patient on the posterior wall near right PV antra and two patients on the posterior wall near the left PV antra. At a mean follow-up of 5.6 months, a total of 5 patients (11.6%) experienced a recurrence. Patients experiencing a recurrence had more frequently non-PV substrate (80.0% vs 23.7%, p=0.024) and lower CV magnitude at CL 600 ms pre-PVI (72.3 cm/s vs 83.1 cm/s, p=0.04). At survival analysis for 34 patients (79.1%) out of the 2 months blanking period, patients with non-PV substrate had lower freedom from AF recurrence (56% vs 90%, p=0.0028), Figure 2. Conclusion In patients with paroxysmal AF undergoing index PVI, non-PV substrate or triggers can be found in up to 37.1% of cases. Non-PV substrate is associated with worse arrhythmic prognosis.Figure 1Figure 2

Impact of residual induction number of non-pulmonary vein foci on the 2-year outcomes in patients with paroxysmal atrial fibrillation.

Residual non-pulmonary vein (PV) foci are significantly associated with atrial fibrillation (AF) recurrence after pulmonary vein isolation (PVI). However, we previously reported among patients with non-PV foci induced only once, none experienced AF recurrence. Thus, we aimed to investigate the correlation between the residual induction number of non-PV foci and ablation outcome in paroxysmal AF patients. We investigated 55 paroxysmal AF patients with residual non-PV foci after PVI and ablation of non-PV-foci. Study patients were classified into the residual one-time induction of non-PV foci (residual OTI-nPVF) group (n = 23) and residual repeatedly induced non-PV foci (residual RI-nPVF) group (n = 32). Furthermore, the residual RI-nPVF group was divided into the low inducibility group (n = 10) and high inducibility group (n = 22) according to the presence or absence of non-PV foci provoked by two sets of drug induction tests (non-PV foci inducibility). In addition, the latter was divided into the ablation group (n = 14) or observation group (n = 8). The 2-year AF recurrence-free rate in the residual RI-nPVF group was significantly lower compared to the residual OTI-nPVF group (53% vs. 90%, p = 0.018). There was no significant difference of the 2-year AF recurrence-free rates in the inducibility of non-PV foci (p = 0.913) and the presence or absence of ablation (p = 0.812) in the residual RI-nPVF group. Among paroxysmal AF patients, the presence of residual RI-nPVF was associated with higher AF recurrence compared to residual OTI-nPVF. Furthermore, within residual RI-nPVF subgroup, non-PV foci inducibility or ablation of some residual RI-nPVF did not affect ablation outcome.

Novel automated atrial pacemapping technique based on intracardiac pattern matching to identify the location of ectopic atrial activity.

Atrial ectopy from the pulmonary veins and non-pulmonary vein foci can trigger atrial fibrillation. In addition, the elimination of atrial ectopy is important to prevent recurrence. The intracardiac pattern matching technique has been reported as a useful method to manually visualize the location of triggers regardless of their frequency. We combined the original intracardiac pattern matching method with the automapping setting of CARTO CONFIDENCE and discovered the automated atrial pacemapping technique. We report two cases in which this technique was used to eliminate the atrial triggers. This technique achieved a time reduction and high-resolution mapping.

Evaluation of an Optimized Workflow for the Radiofrequency Catheter Ablation of Paroxysmal Atrial Fibrillation.

BACKGROUND A significant number of atrial fibrillation (AF) recurrences occur after initial ablation, often due to pulmonary vein reconnections or triggers from non-pulmonary veins. MATERIAL AND METHODS Patients with paroxysmal AF who underwent radiofrequency catheter ablation for the first time were enrolled. Base on propensity score matching (1: 1 matching), 118 patients were selected for an optimized workflow for the radiofrequency catheter ablation of paroxysmal AF (OWCA) group and a conventional group. Comparative analysis of the acute and 12-month clinical outcomes was conducted. Moreover, an artificial intelligence analytics platform was used to evaluate the quality of pulmonary vein isolation (PVI) circles. RESULTS PVI was successfully achieved in all patients. Incidence of first-pass isolation of bilateral PVI circles was higher (P=0.009) and acute pulmonary vein reconnections was lower (P=0.027) in the OWCA group than conventional group. The OWCA group displayed a significant reduction in the number of fractured points (P<0.001), stacked points (P=0.003), and a greater proportion of cases in which the radiofrequency index achieved the target value (P=0.003). Additionally, the contact force consistently met the force over time criteria (P<0.001) for bilateral PVI circles in the OWCA group, accompanied by a shorter operation time (P=0.017). During the 12-month follow-up period, the OWCA group exhibited a higher atrial arrhythmia-free survival rate following the initial ablation procedure than did the conventional group. CONCLUSIONS The optimized workflow for radiofrequency catheter ablation of paroxysmal AF could play a crucial role in creating higher quality PVI circles. This improvement is reflected in a significantly elevated 12-month atrial arrhythmia-free survival rate.

Impact of Atrial Fibrillation Triggers on Long-Term Outcomes of a Second Catheter Ablation of Nonparoxysmal Atrial Fibrillation.

Background: Catheter ablation (CA) of atrial fibrillation (AF) triggers, including non-pulmonary vein (PV) foci, contributes to improved procedural outcomes. However, the clinical significance of an AF trigger ablation during second CA procedures for nonparoxysmal AF is unknown. Methods and Results: We enrolled 94 patients with nonparoxysmal AF undergoing a second CA. Intracardiac cardioversion during AF using high-dose isoproterenol was performed to determine the presence or absence of AF triggers. PV re-isolations were performed if PV potentials recurred, and if AF triggers appeared from any non-PV sites, additional ablation was added to those sites. We investigated the incidence of atrial arrhythmia recurrence (AAR) >3 months post-CA. Of the 94 enrolled patients, AF triggers were identified in 65 (69.1%), and of those with AF triggers, successful elimination of the triggers was achieved in 47 patients (72.3%). Multivariate analysis revealed that no observed AF triggers were a significant predictor of AAR (hazard ratio [HR] 1.97, 95% confidence interval [CI] 1.21-3.46, P=0.019). In a subanalysis of the patients with AF triggers, multivariate analysis showed that unsuccessful trigger ablation was significantly associated with AAR (HR 5.84, 95% CI 2.79-12.22, P<0.01). Conclusions: Having no observed AF triggers during a second CA session significantly increased the risk of AAR, as did unsuccessful CA of AF triggers.

Prospective 1-year results of atrial fibrillation ablation using the pentaspline pulsed field ablation catheter: The initial French experience

BackgroundPulsed field ablation has recently emerged as an interesting non-thermal energy for atrial fibrillation ablation. At a time of rapid spread of this technology, there is still a lack of prospective real-life data. AimTo describe multicentre prospective safety and 1-year efficacy data in three of the first French centres to use pulsed field ablation. MethodsAll consecutive patients undergoing a first pulsed field ablation were included prospectively. The primary outcome was freedom from documented atrial arrhythmia. The safety endpoint was a composite of major adverse events. Univariate and multivariable analyses, including patient and procedural characteristics, were performed to identify factors predictive of recurrence. ResultsBetween May 2021 and June 2022, 311 patients were included (paroxysmal atrial fibrillation in 53%, persistent atrial fibrillation in 35% and long-standing persistent atrial fibrillation in 11%). Additional non-pulmonary vein pulsed field ablation applications were performed in 104/311 patients. One-year freedom from arrhythmia recurrence was 77.6% in the overall population and was significantly higher in patients with paroxysmal atrial fibrillation (88.4%) compared with patients with persistent atrial fibrillation (69.7%; P<0.001) and those with long-standing persistent atrial fibrillation (49.0%; P<0.001). The major complication rate was 2.6% (tamponade in four patients, stroke in two patients and coronary spasm in one patient). Besides the usual predictors of recurrences (left atrium size, CHA2DS2-VASc score, type of atrial fibrillation), the presence of atrial fibrillation at procedure start was independently associated with arrhythmia recurrence (hazard ratio: 2.04, 95% confidence interval: 1.10–3.77). ConclusionIn this prospective multicentre real-world study, pulsed field ablation for atrial fibrillation ablation seems to be associated with a good safety profile and rather favourable acute and 1-year success rates.

Predictors of nonpulmonary vein triggers for atrial fibrillation: A clinical risk score

BackgroundTargeting non-pulmonary vein triggers (NPVTs) after pulmonary vein isolation may reduce atrial fibrillation (AF) recurrence. Isoproterenol infusion and cardioversion of spontaneous or induced AF can provoke NPVTs but typically require vasopressor support and increased procedural time. ObjectiveThe purpose of this study was to identify risk factors for the presence of NPVTs and create a risk score to identify higher-risk subgroups. MethodsUsing the AF ablation registry at the Hospital of the University of Pennsylvania, we included consecutive patients who underwent AF ablation between January 2021 and December 2022. We excluded patients who did not receive NPVT provocation testing after failing to demonstrate spontaneous NPVTs. NPVTs were defined as non-pulmonary vein ectopic beats triggering AF or focal atrial tachycardia. We used risk factors associated with NPVTs with P <.1 in multivariable logistic regression model to create a risk score in a randomly split derivation set (80%) and tested its predictive accuracy in the validation set (20%). ResultsIn 1530 AF ablations included, NPVTs were observed in 235 (15.4%). In the derivation set, female sex (odds ratio [OR] 1.40; 95% confidence interval [CI] 0.96–2.03; P = .080), sinus node dysfunction (OR 1.67; 95% CI 0.98–2.87; P = .060), previous AF ablation (OR 2.50; 95% CI 1.70–3.65; P <.001), and left atrial scar (OR 2.90; 95% CI 1.94–4.36; P <.001) were risk factors associated with NPVTs. The risk score created from these risk factors (PRE2SSS2 score; [PRE]vious ablation: 2 points, female [S]ex: 1 point, [S]inus node dysfunction: 1 point, left atrial [S]car: 2 points) had good predictive accuracy in the validation cohort (area under the receiver operating characteristic curve 0.728; 95% CI 0.648–0.807). ConclusionA risk score incorporating predictors for NPVTs may allow provocation of triggers to be performed in patients with greatest expected yield.

P-Wave Morphology From Common Nonpulmonary Vein Trigger Sites Following Pulmonary Vein and Posterior Wall Isolation

BackgroundNon-pulmonary vein (PV) triggers are increasingly targeted during atrial fibrillation (AF) ablation. P-wave morphology (PWM) can be useful because point mapping of AF triggers is challenging. The impact of prior ablation on PWM is yet to be determined. ObjectivesThis study sought to report PWM before and after left atrial (LA) ablation and construct a P-wave algorithm of common non-PV trigger locations. MethodsThis multicenter, prospective, observational study analyzed the paced PWM of 30 patients with persistent AF undergoing pulmonary vein isolation (PVI) and posterior wall isolation (PWI). Pace mapping was performed at the SVC, crista terminalis, inferior tricuspid annulus, coronary sinus ostium, left septum, left atrial appendage, Ligament of Marshall, and inferoposterior LA. The PWM was reported before PVI, then blinded comparisons were made post-PVI and post-PVI + PWI. A P-wave algorithm was constructed. ResultsA total of 8,352 paced P waves were prospectively recorded. No significant changes in the PWM were seen post-PVI alone in 2,775 of 2,784 (99.7%) and post-PWI in 2,715 of 2,784 (97.5%). Changes in PWM were predominantly at the IPLA (53 P waves) with a positive P-wave in leads V2 to V6 before biphasic post-PWI, LA appendage (9 P waves), coronary sinus ostium (6 P waves), and ligament of Marshall (3 P waves). A PWM algorithm was created before PVI and accurately predicted the location in 93% post-PVI + PWI. ConclusionsMinimal change was observed in PWM post-PV and PWI aside from the IPLA location. A P-wave algorithm created before and applied after PVI + PWI provided an accuracy of 93%. PWM provides a reliable tool to guide the localization of common non-PV trigger sites even after PV and PWI.

Long-term Outcomes of Cryoballoon-based Empirical Superior Vena Cava Isolation in Addition to Pulmonary Vein Isolation in Persistent Atrial Fibrillation.

Superior vena cava (SVC) is atrial fibrillation (AF)'s most common non-pulmonary vein (PV) foci. Studies reported conflictory results when SVC isolation (SVCi) was combined with PVi and long-term outcomes were lacking. Therefore, we aimed to evaluate the long-term efficacy and safety of empirical SVCi as an adjunct to cryoballoon-based PV isolation (PVi) in persistent AF ablation. A total of 40 consecutive persistent AF patients (60.6 ± 8.2 years, 52.5% females) who underwent SVCi in addition to PVi compared with a propensity score matched cohort of 40 persistent AF patients (58.6 ± 8.7 years, 50% female) in whom PVi-only was performed. Second-generation cryoballoon (CB2) was used in all procedures. Atrial tachyarrhythmia (ATa) recurrence was defined as the detection of AF, atrial flutter, or atrial tachycardia (≥30 s) after a 3-month blanking period. Pulmonary veins and SVC were successfully isolated in all patients. At a mean of 46.7 ± 7.8 months follow-up, 22 (55%) patients in the PVi-only group, and 27 (67.5%) patients in the PVi + SVCi group were free of ATa after the index procedure (P =.359). Phrenic nerve injury (PNI) was detected in 2 (5%) patients in the PVi-only group (during right PVi) and 2 (5%) patients in the PVi + SVCi group (during SVCi) (P = 1.00). Cox regression analysis revealed that early recurrence was the only predictor of recurrence (hazard ratio 4.88, 95% confidence interval 1.59-14.96; P =.005). Long-term results of our small sample-sized study revealed that CB-based PVi + SVCi was associated with outcomes similar to the PVi-only strategy in patients with persistent AF. Although complication rates were similar between the groups, close follow-up of diaphragmatic movement is crucial to prevent PNI during SVCi.

A novel designed atrial septum linear ablation method (Icho line) for non-pulmonary vein triggers originating from atrial postero-septum and crista terminalis

Abstract Background Therapeutic strategy for non-pulmonary vein (PV) trigger of atrial fibrillation (AF) has not been well established although they are the major cause of AF recurrence after PV isolation. The atrial postero-septum or right atrial crista terminalis (CT) are the common non-PV trigger sites of AF. For them, a focal ablation is often insufficient due to a regional arrhythmogenicity. We devised an original linear ablation method, named "Icho Line". Icho means ginkgo in Japanese. Methods Eight hundred and thirty-two AF ablation patients were retrospectively studied. An AF induction test was conducted after each PV isolation procedure. Non-PV triggers from the postero-septum or CT that initiate AF were analyzed. Premature atrial contractions that did not initiate AF were excluded. A linear ablation was designed horizontally from the anterior right PV isolation line to fossa ovalis in the left atrium. In the right atrium, the opposite side of the left atrial ablation and CT were continuously ablated like the shape of a ginkgo leaf (Figure 1). Results A hundred and fifteen non-PV triggers were detected in 104 patients (12.5%), among which Icho line ablation was performed in 39 patients (37.5%) with documented triggers from the postero-septum or CT (Figure 1). Atrial tachyarrhythmia recurrence free rate in the Icho line group and other non-PV ablation patients were 61.8% and 45.4%, respectively (P=0.54, Figure 2). Conclusions A novel designed Icho line is a feasible and effective ablation strategy covering non-PV triggers from the atrial septum and CT.Icho Line Figure 1Icho Line Figure 2

Abstract 18515: Prevalence of Right and Left Atrium Non-Pulmonary Vein Triggers in Cardiac Amyloidosis Patients Undergoing Atrial Fibrillation Ablation

Introduction: Cardiac amyloidosis (CA) has been associated with an increased risk of atrial arrhythmias due to infiltration of the amyloid protein in the atrial wall. Though non-pulmonary vein(PV) triggers are commonly seen in left atrium, they are also seen in the right side of the heart, so identifying them at the time of ablation is essential. Minimal data exists on the prevalence of triggers in amyloidosis patients. Aim: The study evaluates the prevalence of non-PV triggers during catheter ablation in atrial fibrillation (AF) patients affected by cardiac amyloidosis Methods: This is a study including 74 consecutive patients with an established diagnosis of amyloidosis ATTR diagnosed with cardiac MRI or myocardial biopsy that underwent their first AF catheter ablation. They underwent PV isolation + isolation of left atrial posterior wall and superior vena cava. Additionally, extrapulmonary triggers, which are defined as ectopic triggers originating from sites other than PVs including left atrial appendage (LAA), coronary sinus (CS), interatrial septum, crista terminalis, mitral valve anulus were identified and ablation in all 74 patients. Post procedure, patients were followed up routinely with ECG during office visits, 7-day Holter monitor and event recorders for the duration of 1 year. Results: Isoproterenol-challenge revealed non-PV triggers in 51 (68.9%) patients. These triggers were mostly mapped to LAA (39, 52.7%), CS (30, 40,5%), and crista terminalis (35, 47.3%). Besides, ectopic beats were seen originating from inter-atrial septum (19, 25.6%), mitral valve annulus (10, 13.5%). More than one trigger was found in (68%) patients.At 1-year after the ablation, 65 (87.8%) were arrhythmia-free off AADs. Conclusions: Our findings suggest that non-PV triggers are highly prevalent in cardiac amyloidosis AF patients including a much higher rate crista terminalis firing compared to the standard population.