Arrhythmia Recurrence Rate Research Articles

The Interconnection between Obstructive Sleep Apnea and Persistent Atrial Fibrillation: Pathophysiology, Clinical Implications, and Management Strategies

Obstructive sleep apnea (OSA) is a prevalent sleep disorder characterized by intermittent upper airway obstruction, resulting in recurrent hypoxemia, hypercapnia, and sleep fragmentation. Emerging evidence highlights a significant association between OSA and persistent atrial fibrillation (AF), a complex arrhythmia with substantial morbidity and mortality. This relationship is underpinned by multifaceted pathophysiological mechanisms, including autonomic nervous system dysregulation, structural and electrical cardiac remodeling, systemic inflammation, and heightened oxidative stress. Patients with coexistent OSA and AF exhibit a more challenging clinical course with higher rates of arrhythmia recurrence and resistance to conventional therapies such as antiarrhythmic drugs and catheter ablation. This review explores the intricate interplay between OSA and persistent AF, emphasizing the role of continuous positive airway pressure (CPAP) therapy in modifying arrhythmogenic risk and improving cardiovascular outcomes. Furthermore, the article discusses the importance of multidisciplinary approaches for diagnosis and management, integrating cardiological and sleep medicine perspectives. Understanding this bidirectional relationship is crucial for tailoring therapeutic strategies aimed at mitigating the burden of AF in patients with OSA.

Cryoballoon Pulmonary Vein Isolation in Obese Patients with Atrial Fibrillation Compared to Non-Obese Counterparts: A Meta-Analysis

Introduction: Obesity is an important risk factor for atrial fibrillation (AF) development. Data on cryoballoon ablation (CBA) outcomes in obese patients have so far been scarce. We reviewed the existing literature to compare the efficacy and safety of CBA in obese versus non-obese AF patients. Methods: A systematic literature search was conducted for studies comparing clinical outcomes (arrhythmia recurrence and/or procedural data and/or safety outcomes) between obese and non-obese patients undergoing CBA for AF. Statistical pooling was performed according to a random-effects model with generic inverse-variance weighting of relative risks (RRs) and standardised mean differences (SMDs) computing risk estimates with 95% confidence intervals (CIs). Results: Obese and non-obese patients had comparable arrhythmia recurrence rates (normal versus overweight, RR = 0.95, 95% CI: 0.82–1.11, p = 0.55, I2% = 91%; normal versus class I obesity, RR = 0.97, 95% CI: 0.82–1.13, p = 0.68, I2% = 87%; normal versus class II obesity, RR = 0.98, 95% CI: 0.91–1.07, p = 0.29, I2% = 65%). Procedure time was marginally increased in obese patients compared to non-obese counterparts (normal versus overweight, SMD = 0.05, 95% CI: −0.15–0.26, p = 0.62, I2% = 74%; normal versus class I obesity, SMD = 0.10, 95% CI: −0.00–0.19, p = 0.06, I2% = 2%; overweight versus class I obesity, SMD = 0.11, 95% CI: 0.01–0.21, p = 0.048, I2% = 25%). Regarding radiation exposure, fluoroscopy time was increased in patients with class I obesity compared to normal-weight or overweight patients and dose area product was also increased in obese patients compared to non-obese patients. Lastly, the risk of complications did not differ between obese and non-obese patients. Statistical heterogeneity and the small number of patients included are the main limitations of this study. Conclusion: CBA seems to be effective for obese patients suffering from AF, featuring also similar safety outcomes with non-obese individuals. Radiation exposure was increased in obese patients.

Machine Learning‐Driven Identification of Distinct Persistent Atrial Fibrillation Phenotypes: A Cluster Analysis of DECAAF II

ABSTRACTIntroductionCatheter ablation of persistent atrial fibrillation yields sub‐optimal success rates partly due to the considerable heterogeneity within the patient population. Identifying distinct patient phenotypes based on post‐ablation prognosis could improve patient selection for additional therapies and optimize treatment strategies.MethodsWe studied all patients who underwent catheter ablation of persistent atrial fibrillation in the DECAAF II trial. Out of 44 participating centers, 25% were randomly chosen as a validation set. A Gradient Boosting Method determined essential features for arrhythmia recurrence prediction and the number of clusters was determined according to the average silhouette width. K‐medoids cluster analysis identified subgroups based on these features, and Kaplan–Meier curves were further compared among different clusters.ResultsAmong 815 patients, 570 served as a training set and 245 as a validation set. Using the training set, the GBM model achieved an AUC of 0.874. K‐medoids cluster analysis used LA volume, BMI, baseline fibrosis, and age, resulting in two clusters. Cluster 1 patients were older, had higher baseline fibrosis, higher BMI, and greater LA volume compared to Cluster 2. Atrial arrhythmia recurrence rates were significantly higher in Cluster 1 (51.7% vs. 35.0%, p = 0.0002), and survival analysis showed a significant difference in primary recurrence outcomes (HR = 1.71, p < 0.0001). The validation set confirmed these findings.ConclusionUtilizing machine learning, we identified a high‐risk cluster for procedural failure in catheter ablation of persistent atrial fibrillation within the DECAAF II trial population. The primary differentiating factors of this high‐risk cluster include older age, high left atrial fibrosis, elevated BMI, and increased left atrial volume.

Comparison of Therapeutic Effects Between Pulsed Field Ablation and Cryoballoon Ablation in the Treatment of Atrial Fibrillation: A Systematic Review and Meta-analysis.

Pulsed field ablation (PFA) is a novel nonthermal ablation technique for the treatment of atrial fibrillation (AF) patients, with safety comparable to traditional catheter ablation surgery. The present study aims to evaluate and compare the procedural efficiency and safety profiles of PFA and cryoballoon ablation (CBA) in the management of AF. We performed a systematic search across PubMed, the Cochrane Library, and Embase databases, encompassing the literature up to February 2024, to inform our systematic review and meta-analysis. When assessing outcome indicators, the risk ratio and its corresponding 95% confidence interval (CI) were calculated for dichotomous variables. For continuous variables, the mean difference (MD) and the associated 95% CI were determined. In this scenario, a relative risk (RR) value of less than 1 and an MD value of less than 0 are deemed favorable for the PFA group. This could translate to a reduced likelihood of procedural complications or enhanced procedural performance within the PFA group. In this analysis, 9 observational studies encompassing 2875 patients with AF were included. Among these, 38% (n = 1105) were treated with PFA, while 62% (n = 1770) received CBA. The results indicated that PFA was associated with a significantly shorter procedural duration compared with CBA, with an MD of -10.49 minutes (95% CI, -15.50 to -5.49; P < 0.0001). Nevertheless, no statistically significant differences were observed when comparing the 2 treatment cohorts concerning fluoroscopy time (MD, 0.71; 95% CI, -0.45 to 1.86; P = 0.23) and the recurrence of atrial arrhythmias during follow-up (RR, 0.95; 95% CI, 0.78-1.14; P = 0.57). In terms of perioperative complications, the PFA group showed a significantly decreased risk of phrenic nerve palsy (RR, 0.15; 95% CI, 0.06-0.39; P < 0.0001) and an increased risk of cardiac tamponade (RR, 3.48; 95% CI, 1.26-9.66; P = 0.02) compared with the CBA group. No significant differences were noted between the PFA and CBA groups regarding the incidence of stroke/transient ischemic attack (RR, 0.99; 95% CI, 0.30-3.22; P = 0.99), vascular access complication (RR, 0.87; 95% CI, 0.36-2.10; P = 0.76), atrial esophageal fistula (RR, 0.33; 95% CI, 0.01-8.13; P = 0.50), and major or minor bleeding events (RR, 0.39; 95% CI, 0.09-1.74; P = 0.22). Our research results indicate that compared with CBA, PFA not only shortens the procedure time but also demonstrates noninferiority in terms of fluoroscopy duration and the recurrence rate of atrial arrhythmias. PFA and CBA have both demonstrated their respective advantages in perioperative complications.

Abstract 4146376: Efficacy of Early Vs Delayed Catheter Ablation in Atrial Fibrillation: an Updated Meta-analysis

Background: Although observational studies have shown a higher rate of atrial arrhythmia recurrences in patients with atrial fibrillation (AF) undergoing delayed catheter ablation as compared with early ablation, a recent randomized controlled trial (RCT) did not show any such difference. We aimed to perform an updated meta-analysis of the available studies. Methods: Multiple online databases were searched for studies comparing early ablation (&lt; 1 year) to delayed ablation (&gt; 1 year) in patients diagnosed with AF. The outcome of interest was atrial arrhythmia recurrence at the longest follow up available. Pooled odds ratio (OR) and 95% confidence interval (CI) were calculated using a random-effects model. Results: A total of 8 studies (1 RCT and 7 observational) with 5,171 patients (early ablation n=1,636, delayed ablation n=3,535) were included. Around 70% patients were men, mean age was 61 years and mean duration of follow up was 28 months. Patients with AF undergoing early catheter ablation had a lower rate of atrial arrhythmia recurrence when compared with the delayed ablation group (OR 0.57, 95% CI 0.44 to 0.73, p &lt; 0.0001). Substantial level of heterogeneity was present between the studies (I2 = 67%). Conclusion: Performing catheter ablation early (within 1 year of diagnosis) in patients with AF may lead to significant reduction in atrial arrhythmia recurrence as compared with delayed ablation. The results of this meta-analysis, however, are subject to potential bias and heterogeneity.

Investigating the role of electroanatomical mapping in single-shot pulsed field catheter ablation.

Pulsed field ablation (PFA) is a form of nonthermal energy that has been recently introduced for pulmonary vein isolation (PVI). A multi-electrode pentaspline catheter for delivery of PFA guided by fluoroscopy has become widely available for clinical use. In this study, we aimed to assess whether the addition of electroanatomical mapping (EAM) for confirmation of PVI in the acute phase can increase the efficacy of the procedure in terms of arrhythmia recurrences. A total of 51 patients with atrial fibrillation (AF) scheduled for first time PVI were included in the study. Participants were assigned to receive PVI using fluoroscopy guidance only (Fluoro-only group: 31 patients) or additional validation with EAM (EAM group: 20 patients). Endpoints included arrhythmia recurrence and procedural characteristics. During a 11.2 ± 1.3 months follow-up period, arrhythmia recurrences did not statistically differ between groups (16.1% vs. 20%, p .72). Procedure time was longer in the EAM group (86.5 ± 11.4 vs. 78.4 ± 9.3 min, p .008). EAM revealed 5 nonisolated PVs that were re-ablated using the same catheter. Four patients of the cohort underwent a redo-procedure during the follow-up period. In all 4 cases, at least one reconnected PV was identified. In a cohort of patients with AF undergoing first time PVI using a pentaspline PFA catheter, PVI validation with EAM did not lead to significantly different arrhythmia recurrence rates compared to PVI without EAM. In the acute phase, the rate of nonisolated PVs was low.

Pulsed Field Ablation in Atrial Fibrillation: Initial Experience of the Efficacy and Safety in Pulmonary Vein Isolation and Beyond.

Regional differences in pulsed field ablation (PFA) adoption for pulmonary vein isolation (PVI) with additional posterior wall ablation (PWA) in Asia remains unknown. We hereby report our experience on the safety and efficacy of PFA in AF ablation. Consecutive AF patients who underwent PFA from September 2022 to January 2024 were included. The primary efficacy endpoint was freedom from atrial arrhythmia recurrence after a 90-day blanking period at 12 months. Safety endpoints included 30 days of all-cause death, cardiac tamponade, stroke, myocardial infarction, and heart failure hospitalization. One hundred and one (72.3% males, 79.2% pAF) patients underwent PFA for AF. Thirty-one (30.7%) had structural heart disease with mean LVEF of 57.4 ± 8.1% and CHA2DS2-VASc score of 1.4 ± 1.3. Twenty-nine (28.7%) underwent additional PWA (PVI + PWA) using PFA. PWA was acutely successful in all patients. Patients who underwent PWA were more likely to have persistent AF and require general anesthesia and electroanatomic mapping (all p < 0.05). Total PFA applications for PVI, LA dwell time, procedural time, and fluoroscopy time were similar between the PVI-only and PVI + PWA groups (all p > 0.05). The 1-year atrial arrhythmia recurrence rates were 10% for pAF and 21% for the persistent AF group. The primary efficacy endpoint was not significantly different between the PVI-only and PVI+PWA groups (12-month KM estimates 90.3% [95% CI, 83.3-97.3] and 82.8% [95% CI, 68.1-97.4], respectively). There were no complications related to PFA use. PFA can be safely, effectively, and efficiently adopted for AF ablation. Additional PWA, if pursued, had similar procedural metrics to the PVI-only strategy without increased complications.

Effectiveness and Safety of PulsedFieldAblation in Patients WithAtrialFibrillation.

As a competitive nonthermal energy technique used in atrial fibrillation (AF), the effectiveness and safety of pulsed field ablation (PFA) has remained uncertain. The authors meta-analysis aimed to investigate the effectiveness and safety of PFA in treating AF patients and compare its outcomes with conventional thermal ablation. The PubMed, Embase, and Cochrane Library databases were systematically searched until January 2024 for relevant studies investigating the use of PFA for AF. A fixed-effects model was used for pooled analysis if the I2 value was<50%; otherwise, a random-effects model was applied. A total of 46 studies were included in this analysis. The single-arm meta-analysis of 40 studies showed an acute pulmonary vein isolation (PVI) rate of 99.79% per pulmonary vein (PV) and 99.47% per patient, with atrial arrhythmia recurrence rates of 12.36%, 12.42%, and 23.28% at 3, 6, and 12months, respectively. The safety outcomes incidence was low. In the comparison of 21 studies between PFA and thermal ablation, PFA demonstrated comparable acute PVI rates but a higher first-pass isolation rate. PFA was associated with a lower incidence of atrial arrhythmia recurrence after 3months and phrenic nerve paralysis or injury, but a higher risk of cardiac perforation or tamponade. Procedure time was shorter with PFA. PFA showed noninferiority to thermal ablation in acute PVI and superiority in first-pass isolation, atrial arrhythmia recurrence, phrenic nerve paralysis or injury, and procedure time. However, PFA treatment exhibited a higher risk of cardiac perforation or tamponade.

Efficacy and safety of catheter ablation for paroxysmal atrial fibrillation as first-line therapy vs. after drug failure -analysis from Japan Nationwide Ablation (J-AB) Registry-

Abstract Background Catheter ablation is an effective rhythm control therapy for atrial fibrillation (AF). Recent advancements in technology have improved the efficacy and safety of this procedure. Current European Society of Cardiology and Japanese Circulation Society guidelines recommend that catheter ablation (CA) for patients with paroxysmal AF (PAF) after failure of drug therapy is classified as Class I, and CA as first-line therapy is categorized as Class IIa. However, there are limited clinical studies directly comparing these groups. Objective This study aimed to compare the efficacy and safety of CA as first-line therapy vs. those after failed drug therapy using data from the Japan Nationwide Ablation (J-AB) Registry led by the Japanese Heart Rhythm Society. Methods Detailed data of patients who underwent catheter ablation for PAF extracted from the J-AB registry were analyzed. Patients were divided into two groups: those who underwent CA as first-line therapy (First-line group) or those who underwent CA after failed drug therapy (Drug failure group). Patients’ characteristics, efficacy and safety of CA were compared between the two groups. Efficacy was assessed by evaluating the recurrence rate of any atrial arrhythmia within one year after the 90-day blanking period, and major safety outcomes were set as severe bleeding complication, stroke, and gastrointestinal disorders during the perioperative period. Result This analysis included 5,011 cases with a median age of 69 years (range 61-75) and 35% females. Comparing patient characteristics between the first-line therapy group (n = 3,447) and the drug failure group (n = 1,564), there are no statistically significant differences between the two groups except in left atrium diameter in echocardiogram (LAD) (38 [34-42] mm vs. 38 [34-43] mm, P &amp;lt;0.001), serum creatinine levels (0.8 [0.7-1.0] mg/dl vs. 0.9 [0.7-1.0] mg/dl, P &amp;lt;0.001), and beta-blocker usage (38.2% vs. 46.7%, P &amp;lt;0.01). A total of 501 recurrence events were observed in this analysis during a median follow-up of 365 [254-390] days. Recurrence rates did not statistically differ between the two groups (log-rank P=0.49). After adjusting for contributing factors with age, gender, body mass index, LAD, and left ventricular ejection fraction in echocardiogram using a multivariate Cox proportional hazards model, efficacy outcomes showed no significant difference between the two groups (adjusted hazard ratio; 1.06 95% confidence interval; 0.88-1.28, P = 0.55). Besides, the two groups had no significant difference in major safety outcomes. Conclusions Catheter ablation as the first-line therapy for paroxysmal atrial fibrillation showed a similar recurrence rate of atrial arrhythmias and adverse events compared to those who underwent catheter ablation after drug failure.

Early ablation leads to better outcome in patients < 55 years with persistent atrial fibrillation

The question of optimal timing for catheter ablation of atrial fibrillation (AF) to achieve best outcomes remains a crucial clinical issue. As AF occurs less frequently in younger patients, data regarding Diagnosis-to-Ablation Time (DAT) is especially limited in patients under the age of 55 years with persistent AF. We therefore analyzed the temporal relationship between initial AF presentation and timing of catheter ablation in this cohort. We conducted a retrospective single-centre study of patients ≤ 55 years with persistent AF who underwent first-time catheter ablation at our center. The cohort was divided into patients that underwent catheter ablation after diagnosis of persistent AF within a DAT of ≤ 12 months and patients with a DAT of > 12 months. A total of 101 patients (median age 51 years; female n = 19 (18.8%)) with persistent AF were included. Ablation was performed within 12 months (“early DAT”) in 51 patients and > 12 months (“late DAT”) in 50 patients. Pulmonary vein isolation was performed using high-power short-duration (HPSD) radiofrequency ablation. Median DAT was 5 months (1–12 months) in the early ablation group and 36 months (13–240 months) in the late ablation group. The median follow-up was 11.3 months (0.03–37.1 months). The rate of any atrial arrhythmia recurrence after a 30-day blanking period was significantly lower in the early DAT group (13/51 patients; 25.5%) as compared to the late DAT group (26/50 patients; 52.0%) (log rank test; p = 0.003). Catheter ablation performed > 12 months after the initial AF diagnosis was an independent predictor for the occurrence of any atrial arrythmia (OR: 2.58; (95%-CI: 1.32–5.07). Early first-time catheter ablation (DAT ≤ 12 months) in patients ≤ 55 years with persistent AF is associated with a significantly lower rate of arrhythmia recurrence.

Embryological Classification of Arrhythmogenic Triggers Initiating Atrial Fibrillation

BackgroundAtrial fibrillation (AF) is a prevalent multifactorial arrhythmia associated with specific single-nucleotide polymorphisms (SNPs). Pulmonary vein (PV) isolation is an established treatment for AF; however, recurrence risk remains caused by AF triggers beyond the PVs. Understanding the embryological origins of these triggers could improve treatment outcomes. ObjectivesThis study aimed to investigate the association between embryologically categorized AF triggers, clinical and genetic backgrounds, and postablation prognosis. MethodsIn cohort 1, comprising 3,067 patients with AF undergoing PV isolation, the clinical characteristics and outcomes were analyzed. Among them, 815 patients underwent genetic analysis using AF-associated SNPs (cohort 2). Patients were delineated based on the developmental origin of the AF triggers: common PV, sinus venosus (SV), and primitive atrium (PA). ResultsSV-origin extra-PV AF triggers occurred in 20.3% (n = 622) of patients, whereas PA-origin triggers occurred in 11.9% (n = 365) of patients in cohort 1. Multivariate analysis of cohort 2 revealed that female sex, lower body mass index, absence of hypertension, rs2634073 near PITX2, and rs6584555 in NEURL1 were associated with SV-AF, whereas nonparoxysmal AF and rs2634073 near PITX2 were predictors of PA-AF. The PA group had a significantly higher arrhythmia recurrence rate after repeated procedures than the common PV (HR: 1.75; 95% CI: 1.34-2.29; P < 0.001) and SV-AF (HR: 1.31; 95% CI: 1.19-1.45; P < 0.001) groups with more de novo AF triggers. However, the incidence of adverse events did not differ significantly among the 3 groups. ConclusionsSV-derived AF triggers may have hereditary factors with a favorable postablation prognosis, whereas PA-derived triggers are linked to AF persistence and poor ablation response. Variants near PITX2 may play a pivotal role in extra-PV triggers.

The Safety and Efficacy of Left Atrial BOX Ablation in Persistent Atrial Fibrillation: A Meta-Analysis.

Circumferential pulmonary vein isolation (CPVI) has a high recurrence rate in managing persistent atrial fibrillation (AF). While some studies suggest that augmenting CPVI with additional left atrial BOX ablation can diminish this recurrence rate among patients with persistent AF, this approach remains controversial. This meta-analysis assesses the safety and efficacy of adjunctive left atrial BOX ablation in treating persistent atrial fibrillation. We conducted a comprehensive literature search across China National Knowledge Infrastructure (CNKI), PubMed, Web of Science, and Cochrane Library, focusing on randomized controlled trials. The primary outcome was the recurrence rate of any atrial arrhythmias (AAs) within one-year post-treatment, with the secondary outcome being the frequency of adverse events related to the surgery. The combination of CPVI and left atrial BOX ablation did not lead to a significant reduction in the overall recurrence rate of atrial arrhythmias (risk ratios (RR) = 0.86, 95% confidence interval (CI) = 0.73-1.02, I2 = 35%). However, subgroup analyses revealed that this therapeutic approach significantly decreased the recurrence rates of all atrial arrhythmias (RR = 0.67, 95% CI = 0.49-0.92, I2 = 15%) and specifically atrial fibrillation (RR = 0.53, 95% CI = 0.37-0.77, I2 = 0%) in patients with a left atrial diameter ≤44 mm. Notably, there was no significant increase in the incidence of procedure-related adverse events (RR = 1.04, 95% CI = 0.56-1.94, I2 = 0%). However, the durations of both the ablation (mean difference (MD) = 19.77, 95% CI = 15.84-23.70, I2 = 0%) and the overall procedure (MD = 15.64, 95% CI = 6.99-24.29, I2 = 0%) were longer due to the additional ablation steps. In patients with smaller left atrial diameters, augmenting CPVI with left atrial BOX ablation significantly lowers the recurrence rates of atrial arrhythmias and atrial fibrillation without elevating surgical risk levels.

Targeting pulmonary vein myocardial sleeves with omnipolar mapping can reduce radiofrequency applications and procedure time: a proof-of-concept study.

There remains an imperative need to accurately map the left atrium in the setting of atrial fibrillation. While the pulmonary vein segmental ostial isolation plays a significant role in atrial fibrillation, clinical attempts to selectively ablate near the pulmonary vein myocardial sleeves have demonstrated a higher recurrence rate of arrhythmia given less precise mapping modalities. However, novel omnipolar mapping technology coupled with Advisor™ HD Grid Mapping Catheter may provide an advantageous profile to map and selectively ablate near the myocardial sleeves. This retrospective cohort underwent ablation targeting the pulmonary vein myocardial sleeves with the use of omnipolar mapping technology and later wide area circumferential ablation (WACA) was performed. The findings of this study demonstrated a few number of lesions were required to achieve all PVI targeting PVMS at 36 (95% CI 32-41) compared to WACA at 81 (95% CI 73-90). PVMS radiofrequency time was shorter at 314s (95% CI 278-350s) compared to 799s (95% CI 692-906s) for WACA. Mean procedure time to complete PVMS was 59min (95% CI 53-65) and to complete WACA was 90min (95% CI 80-100). Precision ablation near PVMS coupled with omnipolar technology may provide a superior profile in reducing procedure time and number of ablative lesions compared to WACA in the setting of atrial fibrillation with possible similar results. Future investigation using randomized controlled trials can help further support these findings.

Implementation of a Patient Decision Aid for Atrial Fibrillation Ablation Improves Patient Procedural Knowledge but Does Not Impact Perceived Involvement With the Shared Decision-Making Process.

Shared decision-making (SDM) is a method for a patient and physician to cooperatively consider a diagnostic or therapeutic option, ultimately empowering the patient to make an informed decision. Atrial fibrillation (AF) ablation is a procedure that would benefit from SDM given the risk of serious adverse events, the high rate of arrhythmia recurrence, and alternative treatment options. Implementing a patient decision aid (PDA) may help facilitate AF ablation SDM by succinctly conveying important information to patients. Patients scheduled for initial AF catheter ablation were randomized to a virtual SDM visit utilizing a PDA, which covered procedural risks and benefits, or a virtual control visit with a tool outlining periprocedural processes. Preoperatively, patients completed a questionnaire assessing procedural risk and benefit knowledge, as well as perceived involvement with the decision-making process. Unpaired t-tests were used to compare groups. The SDM group scored significantly better overall on knowledge-based questions compared to the control group (69% correct [n=34] vs 53% [n=32]; P=0.00013). In particular, the SDM group was significantly more likely to answer questions correctly about stroke risk (P=0.01), anticoagulation (P=0.01), and potential need for additional procedures (P=0.03 and P=0.03). Perceived involvement in the decision-making process was overall not improved with PDA use (4.7 vs 4.6 out of 5; P=0.72). The addition of a PDA for AF ablation significantly improved procedural knowledge but did not impact patients' perceived involvement in the decision-making process compared to traditional preprocedural discussion alone.

Cryoballoon-Assisted Pulmonary Vein Isolation and Left Atrial Roof Ablation Using a Simplified Sedation Strategy without Esophageal Temperature Monitoring: No Notable Thermal Esophageal Lesions and Low Arrhythmia Recurrence Rates after 2 Years.

Atrial fibrillation (AF) ablation is increasingly effective for managing heart rhythm but poses risks like esophageal fistulas. Minimizing esophageal thermal lesions while simplifying procedures is crucial. This prospective study involved 100 consecutive AF patients undergoing cryoballoon ablation with simplified sedation, without esophageal temperature monitoring. Patients with paroxysmal AF (Group A) received pulmonary vein isolation only, while those with persistent AF (Group B) also had left atrial roof ablation. Gastroesophageal endoscopy was performed post-procedure to detect lesions, and cardiological follow-ups were conducted at 3, 12, and 24 months. The cohort included 69% men, with a median age of 65.5 years. Post-ablation endoscopy was performed in 92 patients; esophageal lesions were found in 1.1% of Group A and none of Group B. GERD was diagnosed in 14% of patients, evenly distributed between groups and not linked to lesion occurrence. Gastric hypomotility was observed in 16% of patients, with no significant difference between groups. At 24 months, arrhythmia-free survival was 88% in Group A and 74% in Group B. Cryoballoon-assisted pulmonary vein isolation, with or without additional left atrial roof ablation and without esophageal temperature monitoring during a simplified sedation strategy, shows low risk of esophageal thermal injury and effective ablation outcomes.

The role of high density mapping in cathether ablation of paroxysmal atrial fibrillation - preliminary results

Abstract Introduction Despite technical progress and numerous approaches in ablation strategies, long-term success in paroxysmal atrial fibrillation (PAF) treatment is still suboptimal. Non-transmural ablation lesions in antral isolation lines, causing late electrical reconnection between pulmonary veins (PVs) and left atrium (LA) could present one of the potenital issues for reduced effectiveness of radiofrequency cathether ablation (RFCA). Potentially, these lesions can be identified with high-density (HD) mapping as low voltage, fragmented electrocardiograms (LFEGMs) representing gaps in antral isolation lines. Purpose To compare the long-term pulmonary vein isolation (PVI) durability of two PVI verification methods (circumferential vs high-density mapping catheter) after catheter ablation of PAF. Methods Thirty-three patients with PAF were prospectively randomized to PVI verification by either circumferential mapping catheter (CM group) or HD mapping catheter (HD group). Patients in both groups underwent PVI according to the CLOSE protocol with PVI verification after a 30 minute waiting period. Additionally, in the HD group antral ablation lines were mapped to search for LFEGMs that were defined as fragmented signals (at least 3 deflections) and/or conduction to the LA during stimulation on the ablation line (10 mA at 1 msec) and/or voltage amplitude above 0.1 mV. If LFEGMs were found, additional ablations were performed until electrical inactivity was confirmed with the HD catheter. To monitor AF reccurence 6-day continuous holter ECG was performed after 3, 6, and 12 months after the initial procedure. Arrhythmia recurrence was defined as any atrial tachyarrhythmia lasting more than 30 seconds. Patients also underwent a mandatory second procedure 12 months after the initial PVI, during which HD re-mapping was performed to test durability of PVI and absence of conducting gaps in antral isolation lines. Results There were 16 patients in the CM group and 17 patients in the HD group. Baseline characteristics (gender, age, body mass index, LA volume index, left ventricular ejection fraction, CHA2DS2VASc score) did not significantly differ between the groups. Procedural characteristic are summarized in Table 1. There were significantly more isolated PVs at the remapping procedure in the HD group compared to the CM group (91.2% (62/68) vs 75.0% (48/64); P=0.021). There were also significantly more patients with all PVs durably isolated in the HD group (82.4% (14/17) vs 37.5% (6/16); P=0.008). However, arrhythmia recurrence rate was similiar between the CM and HD group (43.8% (7/16) vs 35.3% (6/17); P=0.640). Conclusion HD mapping improved PVI durability after 12 months compared to standard CM verification. However, lower number of isolated PVs in the HD group did not have an impact on arrhythmia reccurence.

Long-term success and predictors of atrial arrhythmia recurrence following left atrial flutter ablation

Abstract Background In recent years, success rate of left atrial flutter (LAFL) ablation has witnessed improvement, attributed to enhanced comprehension of the arrhythmia mechanism and technological advancements. However, the recurrence rate and specific types of atrial arrhythmias, along with their potential predictors, remain inadequately understood. Purpose The aim of this study is to assess the factors influencing the efficacy, safety, and long-term success of radiofrequency (RF) ablation for LAFL. Methods Patients with sustained LAFL undergoing RF ablation were included in the study. LAFL mapping employed a combination of activation, voltage, and entrainment with 3D electroanatomical mapping. RF ablation targeted a protected isthmus of slow conduction, and if not localized, it involved creating lines of conduction block transecting the reentrant circuit or empirically created lines. Ablation success was defined as clean arrhythmia termination during RF application and no LAFL induction with pacing maneuvers. Follow-up included outpatient visits at 6 and 12 months. Ablation success at follow-up was defined as the absence of arrhythmia recurrence (≥30s) at regular outpatient or emergency department visits. Clinical and electrophysiological characteristics were analyzed and correlated with ablation success, complications, and freedom from arrhythmia recurrences at follow-up. Results The study included 104 consecutive patients undergoing LAFL ablation (67.5 ± 11.3 years, 67% male). Clinical characteristics comprised 12 with HFrEF, 44 with structural heart disease, 25 with valvular heart disease, 43 with previous pulmonary vein isolation (PVI) ablation, and 39 with significant left atrium enlargement. Simultaneous cavotricuspid isthmus ablation (CTI) was performed in 46 patients. LAFL cycle length was 293±68 ms, with more than one LAFL mechanism (2.0±0.8 mechanisms) demonstrated in 76 patients (73%). The most common LAFL mechanism was perimetral reentry (37%). LAFL was successfully ablated 83% of cases, with 7 patients experiencing complications (4 tamponades and 3 sinus node dysfunctions following LAFL termination). At a median follow-up of 28 months, 35 patients (34%) had AFL recurrence, and 15 of them required a second ablation procedure. No factor was associated with LAFL recurrence, except for a short LAFL cycle length (P=0.04) at the ablation procedure. Demonstration of more than one LAFL mechanism (P=0.48) or LAFL termination by focal or linear RF application (P=0.99) were not associated with AFL recurrences at follow-up. Conclusions Despite the relatively high efficacy of LAFL ablation, the rate of atrial arrhythmia recurrences at follow-up after a single procedure remains elevated, predominantly in the form of AFL rather than AF. Short LAFL cycle length at the index procedure appears to be a significant predictor of these recurrences. Arrythmia cycle length proved to be predictive factor of LAFL ablation success rate.Peri-veinal left AFL, LAT map, CranialPeri-veinal left AFL, LAT map, PA

One-year freedom from arrhythmia following radiofrequency ablation using proactive oesophageal cooling

Abstract Background Proactive esophageal cooling is increasingly being utilized, and is now FDA cleared, to reduce the likelihood of ablation-related esophageal injury resulting from radiofrequency (RF) cardiac ablation of atrial fibrillation (AF). One-year follow-up from the largest randomized controlled study, the IMPACT trial, showed a trend towards improvement in long-term efficacy versus luminal esophageal temperature (LET) monitoring. With larger data sets now available for analysis, we sought to determine 1-year freedom from atrial arrhythmia associated with the use of proactive esophageal cooling. Methods Data from 2 trials comparing freedom from atrial arrhythmia after RF ablation using proactive esophageal cooling to LET monitoring were combined. Data were analyzed using a stratified Cox proportional hazards model to compare arrhythmia recurrence rates, with R statistical analysis software. Results Data from 631 patients across two studies comparing arrhythmia outcomes for proactive oesophageal cooling versus LET monitoring were analysed. Mean patient age was 66.4±9.8 years, and 37.4% were female. Arrhythmias were 56.3% paroxysmal AF and 43.7% persistent or long-standing persistent AF. Freedom from atrial arrhythmia at one year was 77.2% for patients receiving proactive oesophageal cooling and 64.4% for patients receiving LET monitoring (Figure 1), with a hazard ratio for cooling of 0.65 (95% CI 0.43 to 0.99, P = 0.044). Conclusions Proactive oesophageal cooling was associated with significantly greater freedom from atrial arrhythmia at one year when compared to LET monitoring during RF ablation.

Left ventricular wall thickening predicts left atrial low voltage areas in patients undergoing catheter ablation for atrial fibrillation

Abstract Background The success rate of circumferential pulmonary vein isolation (CPVI) remains suboptimal in patients with paroxysmal and persistent atrial fibrillation; moreover, the detection of low voltage areas (LVA) in the left atrium does predict an even higher recurrence rate of atrial tachyarrhythmias after the procedure. Left ventricular wall thickening (LVWT) is known to correlate with left atrial volume; however, no data is available whether LVWT is predictive of the presence of left atrial LVA. Purpose The aim of this study was to investigate whether LVWT is predictive of left atrial LVA and to verify that the presence of LVA confer a higher arrhythmia recurrence rate after catheter ablation for atrial fibrillation. Methods A total of 374 patients who undervent CPVI with the use of 3D electroanatomical mapping system as a primary procedure were enrolled in the study. Transthoracic echocardiography was performed in all patients prior the procedure with measurement of the thickness of the septum and the posterior wall. Patients were classified based on LVWT as normal (females:≤9mm, males:≤10mm), borderline (females:10-11mm, males: 11-12mm) and increased (females:≥12mm, males:≥13mm). A detailed left atrial voltage map was obtained in all patients prior to ablation with the identification of LVA (bipolar voltage &amp;lt;0.5mV with an area &amp;gt;5cm2). Arrhythmia recurrence was defined as documented atrial fibrillation or atrial tachycardia lasting for at least 30 seconds. Results Among 374 patients (mean age: 59.0±10.2 years, 131 females) 94, 195 and 85 were considered to be normal, borderline and increased based on LVWT, respectively. LVA were found in 29.9% (112/374) of patients. According to LVWT, LVA were detected in 16.0% (15/94), 31.3% (61/195) and 42.4% (36/85) in patients with normal, borderline and increased wall thickness, respectively, p=0.005. Patients with left atrial LVA had a higher [60.7% (68/112)] arrhythmia recurrence compared to those without low voltage areas [35.1% (92/262)] during a mean follow-up of 2.1±1.9 years, p&amp;lt;0.0001. Conclusions Left ventricular wall thickening predicts the presence of left atrial low voltage areas in patients undergoing catheter ablation for atrial fibrillation. Low voltage areas confer a higher arrhyhtmia recurrence rate during follow-up.

Radiofrequency catheter ablation for redo procedures after pulmonary vein isolation with the cryoballoon technique: 9-year outcome

Abstract Catheter ablation has become the first line of therapy in patients with symptomatic, recurrent, drug-refractory atrial fibrillation. Cryoablation has been shown to be a safe and effective technique for pulmonary vein isolation. However, there is a significant arrhythmia recurrence rate after cryoablation procedures and there are no established strategies for redo procedures in these patients. Therefore, we have summarized our experience with radiofrequency catheter ablation for redo procedures after pulmonary vein isolation with the cryoballoon technique (including an analysis of pulmonary vein conduction recovery patterns after procedures performed with the first or second generation cryoballoon). Methods Two hundred and twenty patients (paroxysmal AF: 140 patients, persistent AF: 80 patients) had to undergo a redo procedure after initially successful circumferential PV isolation with the cryoballoon technique (First generation: 110 patients (group A); second generation: 110 patients (group B)). The redo ablation procedures were performed using a segmental approach or a circumferential ablation strategy (three-dimensional mapping system) depending on the intra-procedural findings. Results During the redo procedure, a mean number of 1.6 re-conducting PVs were detected (using a circular mapping catheter; group A: 2.2 re-conducting PVs, group B: 1.0 re-conducting PVs). There was a slightly higher incidence of chronic PV reconnections related to the left-sided PV ostia than to the right-sided PVs in both groups. Furthermore, sites of chronic PV reconnection were found more frequently in the inferior parts of the PV ostia than in the superior parts. In 97 patients in group A, a segmental approach was sufficient to eliminate the residual PV conduction because there were only a few recovered PV fibers (1-3 reconnected PVs; group A1). In the remaining 13 patients in group A, a circumferential ablation strategy was used because of a complete recovery of the PV-LA conduction of all four pulmonary veins (group A2). In group B, a segmental approach was sufficient in nearly all patients (109/110) because there was only a minor reconnection of 1-2 PVs. All recovered PVs could be isolated sucessfully again. At 108-month follow-up, 69.1 % of all patients were free from an arrhythmia recurrence (152/220 patients; group A: 72/110 patients (65.5 %), group B: 80/110 patients (72.3 %)). There were no major complications in both groups. Conclusions In patients with an initial circumferential PVI using the cryoballoon technique, a repeat ablation procedure can be performed safely and effectively using radiofrequency catheter ablation. In most cases only a few re-conducting PV fibers were found and therefore, a segmental re-ablation approach seems to be sufficient in the majority of patients (especially in patients treated with the second generation cryoballoon).