Catheter Ablation Of Persistent Atrial Fibrillation Research Articles

Efficacy and safety of radiofrequency ablation versus cryoballoon ablation for persistent atrial fibrillation: a systematic review and meta-analysis of randomized controlled trials.

Persistent Atrial Fibrillation (PeAF) is a challenging case for rhythm control modalities. Catheter ablation is the mainstay in PeAF management; however, data regarding the comparative safety and efficacy of cryoballoon ablation (CBA) versus radiofrequency ablation (RFA) for PeAF is still limited. We aim to compare the safety and efficacy of CBA versus RFA for PeAF ablation. We conducted a systematic review and meta-analysis synthesizing randomized controlled trials (RCTs), which were retrieved by systematically searching PubMed, EMBASE, Web of Science, SCOPUS, and Cochrane through October 2023. RevMan version 5.4 software was used to pool dichotomous data using risk ratio (RR) and continuous data using mean difference (MD) with a 95% confidence interval (CI). CRD42023480314. Three RCTs with 400 patients were included. There was no significant difference between RFA and CBA regarding AF recurrence (RR: 0.77, 95% CI [0.50, 1.20], P = 0.25), atrial tachycardia or atrial flutter recurrence (RR: 0.54, 95% CI [0.11, 2.76], P = 0.46), and any arrhythmia recurrence (RR: 0.96, 95% CI [0.70, 1.31], P = 0.80). CBA was significantly associated with decreased total procedure duration (MD: - 45.34, 95% CI [- 62.68, - 28.00], P < 0.00001), with no significant difference in fluoroscopy duration (MD: 3.59, 95% CI [- 5.13, 12.31], P = 0.42). Safety parameters were similar in both groups, including the incidence of any complications, phrenic nerve palsy (RR: 2.91 with 95% CI [0.31, 27.54], P = 0.35), access site complications (RR: 0.33 with 95% CI [0.05, 2.03], P = 0.23), and pericardial effusion. In PeAF catheter ablation, CBA is comparable to RFA in terms of safety and efficacy. Also, CBA is associated with a shorter total procedure duration.

Initial real-world data on catheter ablation in patients with persistent atrial fibrillation using the novel lattice-tip focal pulsed-field ablation catheter.

Technological advancements have contributed to the enhanced precision and lesion flexibility in pulsed-field ablation (PFA) by integrating a three-dimensional mapping system combined with a point-by-point ablation strategy. Data regarding the feasibility of this technology remain limited to some clinical trials. This study aims to elucidate initial real-world data on catheter ablation utilizing a lattice-tip focal PFA/radiofrequency ablation (RFA) catheter in patients with persistent atrial fibrillation (AF). Consecutive patients who underwent catheter ablation for persistent AF via the lattice-tip PFA/RFA catheter were enrolled. We evaluated acute procedural data including periprocedural data as well as the clinical follow-up within a 90-day blanking period. In total, 28 patients with persistent AF underwent AF ablation either under general anaesthesia (n = 6) or deep sedation (n = 22). In all patients, pulmonary vein isolation was successfully achieved. Additional linear ablations were conducted in 21 patients (78%) with a combination of successful anterior line (n = 13, 46%) and roof line (n = 19, 68%). The median procedural and fluoroscopic times were 97 (interquartile range, IQR: 80-114) min and 8.5 (IQR: 7.2-9.5) min, respectively. A total of 27 patients (96%) were interviewed during the follow-up within the blanking period, and early recurrent AF was documented in four patients (15%) including one case of recurrent AF during the hospital stay. Neither major nor minor procedural complication occurred. In terms of real-world data, our data confirmed AF ablation feasibility utilizing the lattice-tip focal PFA/RFA catheter in patients with persistent AF.

Outcome after cryoballoon ablation of persistent atrial fibrillation in patients with heart failure with preserved ejection fraction versus tachycardiomyopathy: a propensity score-matched analysis

Abstract Introduction Atrial fibrillation (AF) often coexists with heart failure (HF). The aim of the study was to detect differences in outcome between patients with arrhythmia induced cardiomyopathy (AIC)/tachycardiomyopathy and HFpEF undergoing cryoballoon pulmonary vein isolation (cryo-PVI) using a propensity score-based model. Methods In this retrospective observational study, we analysed persistent AF patients with HFpEF and AIC undergoing cryoballoon ablation between 2014 and 2020. AIC was diagnosed ex juvantibus during the first year after ablation at the 3- and 12-month follow-up when LVEF recovered to &amp;gt; 50% and by more than 10% after ablation and a different aetiology for reduced LVEF was excluded. Propensity score matching was used to pair patients based on their age, sex, CHA2DS2-VASc score and left atrial (LA) area. The primary endpoint was the first documented &amp;gt; 30-s recurrence of atrial arrhythmia after a 3-month blanking period during the one-year follow-up. The secondary endpoints were improvements in NYHA class and reduction of LA area. For identification of independent predictors of atrial arrhythmia recurrence after ablation, univariate and multivariate Cox regression analyses were performed. Results Out of 1293 consecutive patients who underwent cryo-PVI, 148 persistent AF patients with HFpEF and 66 patients with AIC were identified. Propensity score matching yielded 46 patients in each group. HFpEF patients were more symptomatic than AIC patients (NYHA: 2.4 +/- 0.5 vs. 2.0 +/- 0,8; p = 0.002). Other baseline characteristics did not differ between the two groups, except LVEF (57 % [IQR: 52-62%] vs. 41% [QR: 35%-45%]; p= 0.002). Kaplan-Meier curves (Figure 1) demonstrated no difference in recurrence-free survival rate between the groups during the 12-month follow-up (71.7 % vs. 56.5%, log-rank P = 0.16). After the 12-month follow-up, the median LA area decreased significantly in the HFpEF group from 25.8 cm2 (IQR: 23.4-29.5 cm2) to 24.6cm2 (IQR: 22.0-29.6 cm2; p = 0.045) and in the AIC group from 26.6 cm2 (IQR: 22.9-31.1 cm2) to 23.0 cm2 (IQR: 18.3-25.2 cm2; p=0.024). At the 12-month follow-up the median LA-area was significantly higher in the HFpEF than in the AIC cohort (p= 0.007). NYHA class improved significantly in both groups from baseline. At the 1-year follow-up NYHA class was similar between both groups (1.6 +/- 0.8 vs. 1.4 +/- 0,6; p = 0.206). After univariate and multivariate analysis, the following predictors of atrial arrhythmia recurrence were identified: body-mass-index (BMI; HR = 1.082, p = 0.015) and LA area (HR = 1.079, p = 0.003). Conclusions Cryoballoon catheter ablation of persistent AF seems to have similar effectiveness on arrhythmia free survival in patients with HFpEF and AIC. NYHA class and LA enlargement improved after ablation in both groups although LA area in HFpEF was higher than in AIC patients at follow-up. BMI and LA area were identified as predictors of arrhythmia recurrence.

Posterior wall isolation with pulsed field ablation or radiofrequency ablation with vein of marshall ethanol ablation for the treatment of atrial fibrillation

Abstract Background In patients undergoing repeat catheter ablation for atrial fibrillation (AF) two ablation strategies beyond pulmonary vein isolation (PVI) have recently gained increased interest: posterior wall isolation (PWI) using pulsed field ablation (PFA) and Vein of Marshall (VoM) ethanol ablation combined with radiofrequency energy ablation (RFA). However, a direct comparison is lacking. Purpose To compare prospectively enrolled patients undergoing repeat catheter ablation for persistent AF using PVI and PWI with PFA (PFA group) vs. PVI and VoM ethanol ablation using RFA (VoM group) regarding procedural characteristics, safety, myocardial injury and outcomes. Methods Patients undergoing redo PFA-PVI with PWI and VoM ethanol ablation with RFA were included. Isolation and bidirectional block were checked using a multipolar mapping catheter. High-sensitivity cardiac troponin T (hs-cTnT) was measured after 24h of ablation. Results A total of 84 patients were included (age 69 [interquartile range (IQR) 63-75] years; ejection fraction 56% [IQR 48-60%]; left atrial size 42 [IQR 37-47] mm), baseline characteristics did not differ significantly between groups. Of these, 54 patients (64%) were in the PFA group and 30 (36%) in the VoM group. The procedure duration (65 [IQR 56-73] minutes vs 116 [IQR 103-142] minutes; p &amp;lt; .001) and fluoroscopic times (11 [IQR 8–14] minutes vs 14 [IQR 12-19] minutes; p &amp;lt; .001) were significantly shorter for the PFA group than for the VoM group. No major complications were observed except for a probable allergic reaction in the VoM group and a transient AV-block in the PFA group. High-sensitivity cardiac troponin levels post ablation were similar between the PFA group and the VoM group with 886 [IQR 627–1260] ng/L and 793 [IQR 543-1199] ng/L, p=0.28, respectively. During follow-up (median duration 230 [IQR 117-370] days), AF recurrence was observed in 15% in the PFA group and in 40% in the VOM group (p ≤ 0.01). Conclusion In patients undergoing repeat catheter ablation for AF, PVI and PWI using PFA is associated with shorter procedure and fluoroscopic times, similar high-sensitivity cardiac troponin levels and a reduced recurrence rate compared to PVI using RFA with additional VoM ethanol ablation.Central Illustration

Reduced heart failure hospitalizations and improved quality of life in cardiac amyloidosis patients undergoing atrial fibrillation ablation

Abstract Background Cardiac amyloidosis (CA) has been associated with an increased risk of atrial arrhythmias and development and worsening of heart failure due to infiltration of the amyloid protein in the atrial wall. Few data exist regarding prognosis, symptoms, and quality of life after catheter ablation of atrial fibrillation in this category of patients. Objective The study evaluates the outcome of hospitalization for heart failure and quality of life in cardiac amyloidosis patients with atrial fibrillation after catheter ablation. Methods This is a study including 102 consecutive patients from two different centers with an established diagnosis of amyloidosis ATTR that underwent their first AF catheter ablation for persistent AF. They underwent pulmonary vein (PV) isolation + isolation of left atrial posterior wall and superior vena cava. Additionally, extrapulmonary triggers were identified and ablated. Post procedure, patients were followed up routinely with ECG during office visits, 7-day Holter monitor and event recorders during the first year followed by biannual checkups during the remaining part of the follow-up period. Quality of life (QoL) was measured using The Minnesota Living Heart Failure Questionnaire (MLHFQ) before Catheter ablation and after 18 months follow up; QoL was compared with T-test. Results 102 patients (mean age 72 ± 6) were included in the study. After 18 months follow up, 72 patients (70.6%) remained arrhythmia-free without antiarrhythmic drugs (Group 1), whereas 30 patients (29.4%) experienced recurrence (Group 2). In Group 1, 9 patients were hospitalized for heart failure, in contrast to 18 patients in Group 2, indicating a higher rate of heart failure hospitalizations associated with arrhythmia recurrence (p=0.02). The Quality of life in group 1 was 62 ±12 points before ablation and 63±16 points at 18 months follow up (p=0.17) while in group 2 was 68±16 points before ablation and 86±12 points at 18 months follow up (p&amp;lt;0.001). Conclusion Catheter ablation for AF in patients with cardiac amyloidosis is associated with reduced hospitalizations for heart failure, along with improvement in QoL.

Peak frequency can be effectively used to characterize atrial remodelling in atrial fibrillation

Abstract Introduction Characterizing atrial fibrillation (AF) substrate can guide ablation strategies, particularly as current efficacy leaves room for substantial improvement. Low voltage zones (LVZs) correlate with atrial fibrosis and scar and can independently predict AF recurrence. Ablation of these zones improves freedom from arrhythmia, but the chaotic nature of atrial excitation frequently results in overestimation of LVZs limiting accurate substrate identification. Purpose While omnipolar voltage (OV) mapping has emerged to address this issue by closely correlating with sinus rhythm (SR) voltage maps, our study builds upon this by investigating a novel parameter, peak frequency (PF), to further refine AF substrate characterization. Methods Patients undergoing catheter ablation for persistent AF were enrolled. OV maps and PF maps were created during AF while bipolar voltage (BV) maps were created in SR with atrial pacing at pacing intervals (PIs) of 600ms and 250ms. Areas were classified as fixed scar (consistent LVZs across all maps), functional remodelling (LVZs in AF OV and SR BV 250ms maps) and non-LVZs (normal voltage across all maps). PF was assessed in these areas and defined as the highest frequency detected in the electrogram. Results Among 20 patients, the average voltage in AF OV maps differed significantly from SR BV 600ms (0.49±0.76mV in AF OV vs. 1.12±0.97mV SR BV 600ms, p&amp;lt;0.001) but not SR BV 250ms maps (0.49±0.76mV in AF OV vs. 0.52±0.84mV SR BV 250ms, p=0.10). Comparing co-registered points, there was a significant difference between AF OV and SR BV 600ms maps (0.21±0.09mV, p&amp;lt;0.001) but not between AF OV and SR BV 250ms maps (0.06±0.04mV, p=0.10). These findings were also consistent with regards to the proportion of LA area occupied by LVZs (42.4±8.2% AF OV, 24.3±7.4% SR BV 600ms and 39.4±6.7% SR BV 250ms; p=0.001). AF OV maps thereby correlated better with SR BV 250ms maps hence representing both fixed scar and functional remodelling. PF values ≥244Hz were predictive of non-LVZs (OR 3.91, 95% CI 3.77-4.07,) with an AUC of 0.71. A PF of ≤214Hz was predictive of fixed scar (OR 17.67, 95% CI 16.82-18.56, p&amp;lt;0.001) with an AUC of 0.90. A PF between 215-236Hz was predictive of functional remodelling (OR 2.83, 95% CI 2.71-2.95, p&amp;lt;0.001) with an AUC of 0.60. The majority of LVZs identified exclusively in AF OV maps exhibited PFs akin to those in non-LVZs highlighting the ability of PF to pinpoint potential overestimations in LVZs. Conclusions PF mapping can effectively discern between areas of fixed scar, functional remodelling, and potential overestimation of LVZs. PF may enhance substrate characterization in AF utilising data solely from electrograms.Trial Design and Zone AssignmentPeak Frequency and Voltage Zones

Atrial voltage analysis following vein of marshall alcohol infusion predicts mitral line block

Abstract Background The vein of Marshall (VOM) is a promising therapeutic target for the atrial fibrillation (AF) treatment, fitting perfectly with the "Coumel triangle" as it contains triggers of focal activities and stable reentries, autonomic parasympathetic and sympathetic connection and it represents substrate for perimitral flutters. Lateral mitral line (ML) represents a fundamental part of the anatomical ablation setup for the treatment of AF but its bidirectional block is very difficult to achieve by endocardial ablations. Ethanol infusion into the VoM (VOM-EI) has demonstrated high effectiveness in facilitating ML block. Newly-formed bipolar lesion after VOM-EI is considered an index of effectiveness of the alcoholization procedure. Voltage analysis assessment after VOM-EI in predicting ML block is poorly investigated. Purpose To compare unipolar and bipolar low-voltage areas (LVAs) along VOM trajectory after VOM-EI, and their role in predicting ML block. Methods We enrolled 59 patients undergoing catheter ablation for persistent AF or mitral isthmus dependent atrial flutter. We performed first a high-density voltage map of the left atrium. After VOM-EI, a LA remap was performed. The area width difference was obtained and defined as ∆LVA (see Figure 1). Normal Bipolar voltage cutoffs were 0.50 mV in case of sinus rhythm or 0.29 mV in case of AF. Unipolar cutoffs were respectively 2.7 mV in sinus rhythm and 1.1 mV in AF. The anatomical lesions set, after VOM-EI, included wide antral PVI, linear lesion for dome and ML isthmus following the newly-formed lesion after the VOM-EI. Systematic lines block validation was performed. ML block was defined after coronary sinus electrograms sequence inversion (septal-to-lateral) during left atrial appendage pacing. In case of residual conduction gaps, RF applications into the coronary sinus-great cardiac vein were done to target residual epicardial gaps. Ablation time to obtain ML block (AblTime) was obtained. Results In our group, 56/59 patients (94.5%) achieved mitral isthmus block. Bipolar and unipolar low voltage areas after VOM-EI were 9.9 ± 6.9 cm2 and 12.2 ± 5.9 cm2 respectively. Bipolar ∆LVAs were significantly lower compared with unipolar ∆LVA (8.2 ± 6.5 cm2 vs 9.4 ± 6.0 cm2; p= 0.03). A strong linear correlation between AblTime and bipolar ∆LVA (R: 0.76) and a significant correlation between AblTime and unipolar ∆LVA (R: 0.6) were found (Figure 2). Patients that required coronary sinus applications to reach ML block (13/59, 22%), presented lower ∆LVAs at logistic regression both at bipolar (p&amp;lt;0.01) and unipolar (p=0.03) analysis. Conclusions Unipolar and bipolar voltage analysis along the mitral isthmus trajectory predicts ML block achievement, with VOM-EI inducing wider unipolar LVAs than bipolar LVAs. Furthermore, wider unipolar and bipolar LVAs post VOM-EI are linked to a shorter AblTime and an increased probability of avoiding the need to target epicardial gaps via the CS musculature.LVA along VOM territory after VOM EI∆LVAs linear correlation with AblTime

Catheter ablation for persistent atrial fibrillation: patterns of recurrence and impact on quality of life and health care utilisation.

Patterns of atrial fibrillation (AF) recurrence post catheter ablation for persistent AF are not well described. This study aimed to describe the pattern of AF recurrence seen following catheter ablation for persistent AF (PsAF) and the implications for healthcare utilisation and quality of life. This was a post-hoc analysis of the CAPLA study, an international, multi-centre study that randomised patients with symptomatic PsAF to pulmonary vein isolation plus posterior wall isolation or pulmonary vein isolation alone. Patients underwent twice daily single lead ECG, implantable device monitoring or three monthly Holter monitoring. 154 of 333 (46.2%) patients (median age 67.3 years, 28% female) experienced AF recurrence at 12-month follow-up. Recurrence was paroxysmal in 97 (63%) patients and persistent in 57 (37%). Recurrence type did not differ between randomisation groups (p=0.508). Median AF burden was 27.4% in PsAF recurrence and 0.9% in paroxysmal AF (PAF) recurrence (p<0.001). Patients with PsAF recurrence had lower baseline left ventricular ejection fraction (PsAF 50% vs PAF 60%, p<0.001) and larger left atrial volume (PsAF 54.2±19.3 ml/m² vs PAF 44.8±11.6 ml/m², p=0.008). Healthcare utilisation was significantly higher in PsAF (45 patients [78.9%]) vs PAF recurrence (45 patients [46.4%], p<0.001) and lowest in those without recurrence (17 patients [9.5%], p<0.001). Patients without AF recurrence had greater improvements in quality of life as assessed by the Atrial Fibrillation Effect on Quality-of-Life (AFEQT) questionnaire (Δ33.3±25.2 points) compared to those with PAF (Δ24.0±25.0 points, p=0.012) or PsAF (Δ13.4±22.9 points, p<0.001) recurrence. AF recurrence is more often paroxysmal after catheter ablation for PsAF irrespective of ablation strategy. Recurrent PsAF was associated with higher AF burden, increased healthcare utilisation and antiarrhythmic drug use. The type of AF recurrence and AF burden may be considered important endpoints in clinical trials investigating ablation of PsAF.

ATRIAL VOLTAGE ANALYSIS FOLLOWING VEIN OF MARSHALL ETHANOL INFUSION PREDICTS MITRAL LINE BLOCK

Abstract Background The vein of Marshall (VoM) is a promising target for atrial fibrillation (AF) treatment, matching with the ‘Coumel triangle‘ by housing triggers, autonomic connections, and serving as a substrate for perimitral flutters. Lateral mitral line (ML) represents a fundamental part for AF treatment, but achieving bidirectional block through endocardial ablations is challenging. VoM ethanol infusion (VOM–EI) facilitates ML block, with the newly–formed bipolar lesion serving as an effectiveness index. Voltage analysis assessment after VOM–EI in predicting ML block is poorly investigated. Purpose To compare unipolar and bipolar low–voltage areas (LVAs) along VOM trajectory after VOM–EI, and their role in predicting ML block. Methods We enrolled 59 patients undergoing catheter ablation of persistent AF or ML–dependent atrial flutter. High–density voltage mapping of left atrium was followed by VOM–EI and LA remapping. The area width difference was obtained and defined as ΔLVA. Normal bipolar voltage cutoffs were 0.50 mV in sinus rhythm or 0.29 mV in AF. Unipolar cutoffs were 2.7 mV and 1.1 mV, respectively. After VOM–EI, anatomical lesions included PVI, linear lesion for dome and ML isthmus. Systematic lines block validation was performed, defining ML block after coronary sinus (CS) electrograms sequence inversion (septal–to–lateral) during left atrial appendage pacing. Radiofrequency (RF) applications into the CS–great cardiac vein targeted epicardial gaps if present. Ablation time for ML block (AblTime) was obtained. Results In our cohort, 94.5% achieved ML block. Bipolar and unipolar low voltage areas after VOM–EI were 9,9 ± 6,9 cm2 and 12,2 ± 5,9 cm2 respectively. Bipolar ΔLVAs were significantly lower than unipolar ΔLVA (8.2 ± 6.5 cm2 vs. 9.4 ± 6.0 cm2; p=0.03) (Fig 1). A strong linear correlation between AblTime and bipolar ΔLVA (R: 0.76), and a significant correlation between AblTime and unipolar ΔLVA (R: 0.6) were found (Fig 2). Patients requiring RF applications into the CS for ML block (13/59, 22%) showed lower ΔLVAs in logistic regression for both bipolar (p&amp;lt;0.01) and unipolar (p=0.03) analyses. Conclusions VOM–EI induces unipolar LVAs wider than bipolar along the mitral isthmus trajectory. Unipolar and bipolar voltage analysis predicts a short time ML block achievement. Moreover, wider unipolar and bipolar LVAs following VOM–EI correlates with higher likelihood to avoid the targeting of epicardial gaps via the CS musculature.

The Yin and Yang of the persistent atrial fibrillation catheter ablation: Posterior wall isolation and novel pulsed field ablation technology.

The Yin and Yang of the persistent atrial fibrillation catheter ablation: Posterior wall isolation and novel pulsed field ablation technology.

Sex-specific outcomes after catheter ablation for persistent AF

BackgroundSex-specific outcomes after catheter ablation (CA) for atrial fibrillation (AF) have reported conflicting findings. ObjectiveWe examined the impact of female sex on outcomes in patients with persistent AF (PsAF) from the Catheter Ablation for Persistent Atrial Fibrillation: A Multicentre Randomized Trial of Pulmonary Vein Isolation vs PVI with Posterior Left Atrial Wall Isolation (CAPLA) randomized trial. MethodsA total of 338 patients with PsAF were randomized to pulmonary vein isolation (PVI) or PVI with posterior wall isolation (PWI). The primary outcome was arrhythmia recurrence at 12 months. Clinical and electroanatomical characteristics, arrhythmia recurrence, and quality of life were compared between women and men. ResultsSeventy-nine women (23.4%; PVI 37; PVI + PWI 42) and 259 men (76.6%; PVI 131; PVI + PWI 128) underwent AF ablation. Women were older {median age 70.4 (interquartile range [IQR] 64.8–74.6) years vs 64.0 (IQR 56.7–69.7) years; P < .001} and had more advanced left atrial electroanatomical remodeling. At 12 months, arrhythmia-free survival was lower in women (44.3% vs 56.8% in men; hazard ratio 1.44; 95% confidence interval 1.02–2.04; log-rank, P = .036). PWI did not improve arrhythmia-free survival at 12 months (hazard ratio 1.02; 95% confidence interval 0.74–1.40; log-rank, P = .711). The median AF burden was 0% in both groups (women: IQR 0.0%–2.2% vs men: IQR 0.0%–2.8%; P = .804). Health care utilization was comparable between women (36.7%) and men (30.1%) (P = .241); however, women were more likely to undergo a repeat procedure (17.7% vs 6.9%; P = .007). Women reported more severe baseline anxiety (average Hospital Anxiety and Depression Scale [HADS] anxiety score 7.5 ± 4.9 vs 6.3 ± 4.3 in men; P = .035) and AF-related symptoms (baseline Atrial Fibrillation Effect on Quality-of-Life Questionnaire [AFEQT] score 46.7 ± 20.7 vs 55.9 ± 23.0 in men; P = .002), with comparable improvements in psychological symptoms (change in HADS anxiety score −3.8 ± 4.6 vs −3.0 ± 4.5; P = .152 (change in HADS depression score −2.9 ± 5.0 vs −2.6 ± 4.0; P = .542) and greater improvement in AFEQT score compared with men at 12 months (change in AFEQT score +45.9 ± 23.1 vs +39.2 ± 24.8; P = .048). ConclusionWomen undergoing CA for PsAF report more significant symptoms and poorer quality of life at baseline than men. Despite higher arrhythmia recurrence and repeat procedures in women, the AF burden was comparably low, resulting in significant improvements in quality of life and psychological well-being after CA in both sexes.

Hybrid ablation for persistent atrial fibrillation: a narrative review.

Treatment for atrial fibrillation (AF) has evolved significantly, with pulmonary vein isolation (PVI) becoming an established treatment. However, the outcomes following catheter ablation for persistent AF remain unsatisfactory. Hybrid catheter-surgical ablation has emerged as a therapeutic approach for persistent AF, combining the strengths of both interventions. The purpose of this narrative review is to comprehensively examine the current state of knowledge regarding hybrid ablation for AF. A thorough PubMed search using the terms "hybrid ablation", "atrial fibrillation", "catheter ablation", and "guideline on cardiology" within the timeframe of 1980 to 2024 resulted in 138,969 articles. Consensus on the selected articles was reached through a series of structured meetings and discussions. PVI has demonstrated higher sinus rhythm maintenance rates, especially for paroxysmal AF. However, the efficacy is not as high for persistent AF. Additional ablation strategies, such as linear ablation, complex fractionated atrial electrogram ablation, low voltage zone ablation as well as posterior wall isolation, lack consistent evidence of effectiveness. Hybrid ablation, involving collaboration between cardiac surgeons and electrophysiologists, presents a promising alternative for hard-to-treat AF. Recent studies report favorable outcomes of hybrid ablation, with atrial arrhythmia-free rates ranging from 53.5% to 76%, surpassing those of catheter ablation alone, which might result from better lesion durability or intervention for non-PV foci and left atrial appendage excision or closure during hybrid ablation. The rate of complications associated with hybrid ablation is higher than catheter ablation alone. While favorable outcomes of hybrid ablation for persistent AF have been reported, it is not recommended for all AF patients due to its invasiveness compared to catheter ablation. Additionally, some patients with persistent AF maintain sinus rhythm with catheter ablation alone. More clinical data are needed to determine which patients are suitable candidates for hybrid ablation.

First clinical data on artificial intelligence-guided catheter ablation in long-standing persistent atrial fibrillation.

Despite advanced ablation strategies and major technological improvements, treatment of persistent atrial fibrillation (AF) remains challenging and the underlying pathophysiology is not fully understood. This study analyzed the multiple procedure outcome and safety of catheter ablation of spatiotemporal dispersions (DISPERS) detected by artificial intelligence (AI)-guided software in patients with long-standing persistent AF. The Volta VX1 software was used for 50 consecutive patients undergoing catheter ablation for persistent AF. First, high-density mapping (78% biatrial) with a multipolar mapping catheter was performed. In addition to pulmonary vein isolation (PVI), ablation of DISPERS was performed aiming at homogenizing, dissecting, isolating, or connecting DISPERS areas to nonconducting anatomical structures. Follow-up contained regular visits at our outpatient clinic at 1, 3, 6, and 12 months including 7-day Holter electrocardiograms. Patients were mainly suffering from long-standing persistent AF (mean AF duration 50.30 ± 54.28 months). Following PVI, ablation of left atrial and right atrial DISPERS areas led to AF cycle length prolongation (mean of 162.0 ± 16.6to 202.2 ± 21.6 ms after) and AF termination to atrial tachycardia (AT) or sinus rhythm (SR) in 12 patients (24%). No stroke or pericardial effusion occurred; major groin complications (pseudoaneurysm n = 1, atrioventricularfistula n = 1) were detected in two patients. After a blanking period of 6 weeks, recurrence of any atrial arrhythmia was documented in 26 patients (52%). The majority of patients presented with organized AT (n = 15) while AF was present in n = 9 patients and AT/AF was observed in n = 2 patients. Twenty-twopatients underwent reablation. During a mean follow-up of 363.14 ± 187.42 days and after an average of 1.46 ± 0.68 procedures, 82% of patients remained in stable SR. DISPERS-guided ablation using machine learning software (the Volta VX1 software) in addition to PVI in long-standing persistent AF ablation resulted in high long-term success rates regarding AF and AT elimination. Most arrhythmia recurrences were reentrant AT. After a total of 1.46 ± 0.68 procedures, freedom from AF/AT was 82%. Despite prolonged procedure times complication rates were low. Randomized studies are necessary to evaluate long-term efficacy of dispersion-guided ablation using AI.

Catheter Ablation of Persistent AF—Where are We Now?

Catheter Ablation of Persistent AF—Where are We Now?

Comparison of additional ablation of spatio-temporal dispersion electrograms and low voltage area beyond pulmonary vein isolation in patients with persistent atrial fibrillation

Abstract Backgrounds Although strategies beyond extensive pulmonary vein isolation (EPVI) including low voltage zone (LVZ) ablation in patients with persistent atrial fibrillation (AF) have not yet been established, recent research showed that ablation targeting spatio-temporal dispersion electrograms (STDE) could achieve high AF-free survival. We hypothesized that EPVI plus STDE approach could reduce AF recurrence after catheter ablation of persistent AF. Purpose The purpose of this study is to assess the AF recurrence after the ablation in different two strategies. Methods We prospectively enrolled consecutive patients with persistent AF undergoing their first catheter ablation at our institution during July 2018 to March 2021. The ablation strategy was divided into 2 groups: 1) EPVI plus LVZ and 2) EPVI plus STDE ablation. STDE was defined as clusters of fractionated electrograms that displayed interelectrode time and space dispersion at a minimum of three adjacent bipolar electrodes such that activation spread over all the cycle length of AF. The definition of LVZ was bipolar amplitude of &amp;lt;0.5mV. Posterior wall isolation was performed if STDE or LVZ were broadly present in posterior wall. The primary endpoint was defined as AF recurrence after the ablation. The blanking period of 3 months was applied. Results Out of 138 patients (66±11 years, 108 men), 64 patients underwent EPVI plus LVZ and 74 EPVI plus STDE ablation. There was no difference in median AF duration (8 [interquartile range (IQR) 4-13] months vs. 12 [IQR 5-22] months; p=0.129) and left atrial volume (151 [IQR 115-168] ml vs. 151 [IQR 127-175] ml; p=0.239) between the two groups. The prevalence of concomitant hypertension (47% vs. 67%; p=0.024) and diabetes mellitus (24% vs. 42%; p=0.027) was lower in the STDE group than in the LVZ group. Posterior wall isolation was performed more frequently in the STDE group than in the LVZ group (38% vs. 19%; p=0.015). At 1 year follow-up, the STDE group achieved higher AF-free rate than the LVZ group (84% [95% confidence interval (CI), 73-91%] vs. 64% [95% CI 52-76%]; P=0.017). Multivariate Cox regression analysis demonstrated that not only AF duration (hazard ratio [HR] 1.03, 95% CI 1.01–1.04; p&amp;lt;0.001), and left atrial volume (HR 1.10, 95% CI 1.02–1.19; p=0.011) but also STDE ablation (HR 0.33, 95% CI 0.14-0.77%, p=0.010) were independently associated with AF recurrence. Conclusions Ablation guided by STDE in addition to EPVI may be a useful treatment strategy for persistent AF.

Abstract 17638: Left Atrial Scar Burden Among Patients With Persistent Atrial Fibrillation Undergoing Catheter Ablation and Its Association With Patient Risk Factors and Risk of Recurrence

Introduction: Left atrial (LA) scar at time of catheter ablation (CA), assessed by bipolar voltage &lt;0.5mV may indicate more advanced AF substrate. It is not known which risk factors are associated with scar burden and whether this is linked to worse clinical outcomes. Hypothesis: We hypothesized that patient demographics and comorbidities are associated with greater scar burden at time of CA and predispose to AF recurrence. Methods: The Real-AF registry is a prospective, observational, multicenter registry of patients undergoing CA with follow-up at 6 and 12 months. LA scar burden was calculated from CARTO as total % LA area &lt; 0.50mV bipolar using the Pentaray catheter at first CA for persistent AF. We evaluated 1503 patients among this cohort using logistic regression modeling of age, sex, CHA2DS2-VASc and LVEF &lt;= 35%, BMI and their association with LA scar burden categorized as 0 to 5% vs &gt;= 6%. In 783 patients with 12-month clinical outcomes a Kaplan-Meier estimator was used to analyze risk of AF recurrence in these two cohorts. Results: Each additional year in age is associated with 1.07 greater odds (p&lt;0.001, 95% CI=1.05, 1.08) of scar area &gt;= 6%. Women had 2.08 greater odds (p&lt;0.001, 95% CI=1.63, 2.65) of abnormal scar area compared to men, while patients with CHF had 1.67 greater odds (p&lt;0.001, 95% CI=1.30, 2.16). Patients with LA scar burden &gt;= 6% experienced significantly higher recurrence of AF compared to those with a lower scar burden (HR=1.8, p=0.0094) including after controlling for operator-specific effects (HR=1.9, p=0.0088), see figure 1. Conclusions: In a large multicenter registry of persistent AF patients undergoing CA, LA scar &gt;=6% was associated with female sex, greater age, and CHF. An increased scar burden is associated with worse 12 month clinical outcomes from CA.

Catheter ablation (CA) for atrial fibrillation and atrial tachycardia in the elderly: Results from a large single center study in 293 patients over 80 years old

Abstract Funding Acknowledgements Type of funding sources: None. Introduction The increasing incidence of atrial arrhythmias in the elderly is mostly adjudicated to the age-dependent development of arhythmic substrate. In recent years, CA has become a standard approach in treating atrial fibrillation (AF) and left and right atrial flutter (AFlut). Data regarding safety and efficacy of CA in patients over 80 years old remains scarce. This study aims to report on our high-volume center experience regarding the safety and efficacy of CA in a large cohort of patients &amp;gt;80 years of age. Methods All patients &amp;gt;80 years undergoing de-novo-CA for AF or AFlut (parox. AF n=85, 29%; pers. AF n=146, 49.8%; left-/right- AFlut n=62, 21.2%) in our institution between 01/2016 and 12/2020 were included (n=293; mean age 82.3 ± 2.27 years). For safety analysis, all complications requiring intervention or causing sequels occurring during or up to 30 days after CA were collected. For efficacy, AF/Aflut-free survival was analysed after a blanking period (3 months) using 7-day Holter ECGs. Results Baseline characteristics are shown in table 1. Most patients suffered from multiple cardiovascular co-morbidities (CHA2DS2-VASc-score 4.45 ± 1.15), &amp;gt;30% were on reduced OAC. Isolation of all pulmonary veins (PV) and/or termination of AFlut with demonstration of bidirectional block across the ablation line was achieved in all patients (procedure success 100%). During a follow-up of 400 ± 446 days, 61.4% of patients remained in stable sinus rhythm after 1.56 ± 0.81 ablations (Figure 1). Single procedure outcome was significantly higher in paroxysmal AF compared to persistent AF (p = 0.03, s. Figure 1b). 32 patients (10.9%) were lost to follow-up. In 17 patients (5.8%) complications occurred: 1 case of pericardial tamponade during PVI and CA of PVCs (LA and CS). 2 patients suffered a stroke within a week after CA of persistent AF and left AFlut, 1 TIA occurred after CA of persistent AF. All patients had been under uninterrupted full-dose OAC. Major groin complications occurred in 13 patients (4.4%). 3 arterial bleeds treated by covered stent implant, 7 pseudoaneurysms needing thrombin injections, 2 infections of the puncture site and 1 patient requiring surgical treatment for a large hematoma. 9 patients underwent pacemaker implantation shortly after CA due to underlying symptomatic sick-sinus-syndrome or higher degree AV-blocks demasked in sinus rhythm, none were procedure-related. Conclusion De novo catheter ablation of AF and AFlut in very old patients is safe and effective. In paroxysmal AF, ablation success rates seem to be similar to those in younger patients and are significantly higher than for persistent AF. After 1.56 ablation procedures, &amp;gt;60% of patients were free of arrhythmia, suggesting that the supposed atrial remodelling does not preclude an interventional treatment approach.

Impact of catheter ablation for persistent atrial fibrillation with heart failure, compared to preserved and reduced ejection fraction

Abstract Funding Acknowledgements Type of funding sources: None. Background Catheter ablation for persistent atrial fibrillation (AF) in patients with heart failure is known to improve heart failure. However, there were few reports comparing the outcomes of catheter ablation for patients with heart failure with reduced ejection fraction (HFpEF) and heart failure with preserved ejection fraction (HFpEF). Method Patients with E/e’ &amp;gt; 15 and EF &amp;gt; 50% on preoperative echocardiography were defined HFpEF, and those with EF &amp;lt; 40% were defined as HFrEF. We compared ablation outcomes and postoperative BNP changes between patients with HFpEF (HFpEF-group) and HFrEF (HFrEF-group). Result There were 166 cases of HFpEF-group and 177 of HFrEF-group among the cases with catheter ablation for persistent AF in our hospital from 2013 to 2021. The median preoperative BNP was 190.7 pg/ml in HFrEF-group and 144.3 in HFpEF-group, significantly higher in HFrEF-group (P=0.001). After a mean follow-up of 37.2 months, maintenance of sinus rhythm without any antiarrhythmic drugs was significantly better in the HFrEF-group (64.4% and 53.6%, p=0.048). After one year of ablation, median BNP was significantly higher in HFpEF-group (HFpEF: 37.5 pg/ml, HFrEF: 22.0 pg/ml; p=0.017), contrary to before ablation. Conclusion Catheter ablation for persistent AF with HFrEF showed better ablation outcomes and improved BNP levels compared to those with HFpEF.

The new tactiflex ablation catheter: reducing the time for radiofrequency atrial fibrillation ablation

Abstract Funding Acknowledgements Type of funding sources: Public hospital(s). Main funding source(s): Azienda Ospedaliero-Univerisitaria delle Marche Background Pulmonary vein isolation (PVI) by radiofrequency (RF) ablation is a well-established and effective treatment for paroxysmal and persistent atrial fibrillation (AF). Compared to low-power-long-duration (LPLD) RF ablation, the high-power-short duration (HPSD) one produces shallower lesions reducing potential adverse effects, without affecting efficacy. The new TactiFlex Ablation Catheter, Sensor Enabled (TFSE), combining a flexible tip with fiber optic-based contact force sensing, can deliver HSPD RF, obtaining a faster PVI. Objective To test feasibility, safety, and effectiveness of RF AF ablation performed by TFSE, comparing it with LPLD RF AF ablation using TactiCath Contact Force Ablation catheter, Sensor Enabled (TCSE). Methods We conducted a prospective study including 50 consecutive patients admitted to our centre for paroxysmal or persistent AF catheter ablation. The patients were randomly divided into 2 groups according to ablation protocol: 25 patients were treated with HPSD performed by TFSE [63 (53-68) years, male 19]; 25 patients were treated with LPLD by TCSE [62 (51-69); male 12). In the HPSD group, the lesions were performed delivering 50W up to 10 seconds with a contact force (CF) index ranging from 5g to 20g. In the LPLD group, the lesions were performed delivering 40W in the anterior segments of veins (LSI 5-5.5) and 35W in the posterior segments (LSI 4-4.5). Results PVI was achieved in 100% of patients in both groups. No periprocedural complication was reported. No statistically significant differences were found in terms of clinical and echocardiographic characteristics. A significant decrease in PVI time was reported in TFSE group for every pulmonary vein (LSPV: 2.14±0.13 min vs 10.63±5.34, p&amp;lt;0.005; LIPV 2.10±0.12 min vs 10.50±5.56 min, p&amp;lt;0.005; RSPV: 2.20±0.14 min vs 10±6.35 min, p&amp;lt;0.005; RIPV 3.10±5.21 min vs 10.40±8.54 min, p&amp;lt;0.005). No difference was reported for the impendence drop (17 Ω, range 15.3-18 in TFSE vs 15 Ω, range 14.5-17.5 in TCSE, p=0.114). A shorter total procedural time (110 min, range 90-121 vs 155 min, range 128-190, p&amp;lt;0.005) and LA mapping time (8 min, range 6-10 vs 13 min, range 11-14, p&amp;lt;0.005) were reported in TFSE group, while no difference was reported in total fluoroscopy time (16 min, range 12-19.30 vs 19 min, range 14-27, p=0,062). The RF total time was superior in the TCSE group. Conclusions In our initial experience, TactiFlex catheter allows a safe, effective and faster PVI in patients affected by paroxysmal and persistent AF undergoing RF ablation. The shorter time for PVI is the main contributor for shortening total procedural times. However, our results have to be confirmed in larger studies.

PO-02-172 CONDUCTION VELOCITY AND CONDUCTION VELOCITY DYNAMICS IN THE LEFT ATRIUM ARE IMPACTED BY STRUCTURAL AND AUTONOMIC MODULATION AND SITES OF CONDUCTION VELOCITY HETEROGENEITY CORRELATE TO RE-ENTRY ACTIVITY IN ATRIAL FIBRILLATION

Structural and autonomic remodelling is proposed to drive atrial fibrillation (AF). Conduction velocity (CV) heterogeneity predisposes cardiac tissue to re-entry mechanisms. The impact of structural and autonomic remodelling on CV dynamics and re-entry formation is unclear. Evaluate the impact structural and autonomic modulation has on CV dynamics and re-entry activity in AF. Local activation times (LATs), voltage and geometry data were obtained from 20 patients undergoing catheter ablation for persistent AF. LATs were obtained at 3 pacing intervals (PI) (600, 400 and 250ms) with pacing from two pacing sites. LATs were used to determine CV dynamics and their relationship to voltage using an automated algorithm. Relationship between sites of enhanced CV heterogeneity defined as rate dependent CV slowing (RDCV) sites (sites exhibiting CV difference (CVd) between PI=600ms and PI=250ms of ≥20% of the mean CVd seen between these PIs for that voltage zone) and re-entry activity in AF was evaluated. Re-entry activity was identified using an automated algorithm and defined as ≥1.5 rotations of 360 degrees. The impact of autonomic modulation on CV dynamics both pharmacologically and with ganglionated plexi stimulation was assessed. A total of 512,082 LAT and voltage points were analysed. Voltage impacts CV (1.36±0.98 nLVZ ≥0.5mV, 1.05±1.03 LVZ 0.2-0.49mV and 0.58±0.37 vLVZ <0.2mV) (Figure 1A-B) and CV dynamics, whereby at nLVZ the curves are steeper (0.03±0.02ms CVd PI 600-400ms, 0.54±1.1ms CVd PI 400-250ms), broader at LVZ (0.16±0.09ms CVd PI 600-400ms, 0.23±1.1ms CVd PI 400-250ms) and flat at vLVZ (0.04±0.01ms CVd PI 600-400ms, 0.05±0.02ms CVd PI 400-250ms) (Figure 1C). Per patient, 5.6±1.1 RDCV sites and 3.4±1.3 sites of re-entry activity were identified. Of the RDCV sites, 72.3% (81/112) correlated to 94.1% (64/68) of re-entry activity sites which were mainly confined to LVZs (59/68, 86.8%). Autonomic modulation affected the CV dynamic curves through increasing rate dependency slowing (Figure 1D). The number of RDCV sites identified were enhanced following autonomic modulation (3.4±1.2 increase per patient). CVs and CV dynamics are impacted by structural remodelling and are influenced by autonomic modulation which enhances CV heterogeneity. CV heterogeneity sites correlate to re-entry activity in AF. Assessment of CV dynamics and heterogenity may help to determine the mechanistic importance of LVZs.