Catheter Ablation Of Atrial Fibrillation Research Articles

The decalogue of the 2024 European Heart Rhythm Association/Heart Rhythm Society/Asia Pacific Heart Rhythm Society/Latin American Heart Rhythm Society consensus document on catheter and surgical ablation of atrial fibrillation.

The decalogue of the 2024 European Heart Rhythm Association/Heart Rhythm Society/Asia Pacific Heart Rhythm Society/Latin American Heart Rhythm Society consensus document on catheter and surgical ablation of atrial fibrillation.

Real-world clinical practice of current periprocedural anticoagulation management in catheter ablation of atrial fibrillation: Data from a large prospective ablation registry.

The guidelines recommend anticoagulation management with uninterrupted warfarin or direct thrombin inhibitors (DTIs) during the atrial fibrillation (AF) ablation periprocedural period. To clarify the Japanese real-world latest periprocedural anticoagulation management during AF ablation. This multicenter observational study included 6232 consecutive AF patients (68.7 ± 10.9 years, 4346 men) who underwent periprocedural anticoagulation therapy using direct oral anticoagulants (DOACs) between January 2022 and August 2023. The mean CHADS2 and CHA2DS2VASc scores were 1.2 ± 1.1 and 2.3 ± 1.5. Bleeding and thromboembolic events occurred in 79 (1.3%) and eight (0.12%) patients. During the periprocedural period, factor Xa inhibitors (FXaIs) were used in 3063 patients (rivaroxaban in 624, apixaban in 1093, and edoxaban in 1345) and DTIs in 3170 including 2583 in whom DTIs were switched from FXaIs. Both the bleeding (0.85% vs. 1.69%, p = .003) and thromboembolic event rates (0.03% vs. 0.23%, p = .036) were significantly lower in the DTI- than FXaI-group. A multivariate analysis showed periprocedural FXaI use was significantly associated with both bleeding events (odds ratio [OR] = 1.92, 95% confidence interval [CI] = 1.20-3.08, p = .006) and cardiac tamponade (OR = 2.74, 95% CI = 1.27-5.9, p = .01). The interval between the last DOAC administration and the procedure was significantly shorter in the DTI- than FXaI-group (4.2 ± 4.9 vs. 19.3 ± 10.7 h, p < .01). In the FXaI-group, the bleeding rate tended to be lower in the minimally interrupted (n = 2105) than uninterrupted group (n = 821) (1.47% vs. 2.56%, p = .06). Two patients in the uninterrupted FXaI-group required surgical management for cardiac tamponade. Our multicenter real-world data demonstrated that anticoagulation with DTIs was a reasonable periprocedural anticoagulation regimen to reduce periprocedural complications.

Silent cerebral lesions after catheter ablation for atrial fibrillation using cryoballoon, hotballoon, laserballoon and radiofrequency catheters: a Bayesian network meta-analysis

BackgroundCatheter ablation (CA) is an effective therapeutic option for patients with symptomatic atrial fibrillation (AF). Previous studies have reported silent cerebral lesions (SCLs) detected by magnetic resonance imaging (MRI) after different CA techniques; however, the results were controversial. Therefore, we performed this network meta-analysis (NMA) to assess the incidence of SCLs after cryoballoon, hotballoon, laserballoon, and radiofrequency ablation (RFA).MethodsDatabases such as PubMed, Embase, and the Cochrane Library were searched systematically. Both pairwise meta-analysis (PMA) and NMA were conducted. The primary outcome was the incidence of new SCLs on MRI after CA procedures.ResultsNine studies were analyzed and 1,057 patients were enrolled. Laserballoon ablation (LBA) had a higher incidence of SCLs than cryoballoon ablation (CBA) [odds ratio [OR] = 1.86, 95% confidence interval [CI] 1.06–3.27, p = 0.032] in the PMA, while no significant difference was detected between the CA techniques according to the NMA. The surface under the cumulative ranking curve (SUCRA) values indicated that CBA may be the best therapeutic option (SUCRA = 81.1%). The NMA results demonstrated similar procedure-related complication rates and mean activated clotting time between CBA (SUCRA = 53.7%, 66.3%), hotballoon ablation (HBA) (SUCRA = 81.5%, 43.6%), LBA (SUCRA = 3.39%, 42.8%) and RFA (SUCRA = 61.3%, 47.3%). LBA therapy required significantly more procedure time than CBA [weighted mean difference (WMD) = 24.36 min, 95% CI 12.51–36.21 min, p = 0.00].ConclusionsCBA treatment had lower incidence of post-procedural SCLs and took less procedure time compared with LBA for patients with AF. The procedure-related complications were comparable between CBA, LBA, HBA and RFA.Systematic Review RegistrationPROSPERO, identifier (CRD42024511110).

Technical standards for performing radiofrequency catheter ablation for atrial fibrillation: a series of consortium standards

Atrial fibrillation (AF) has emerged as a major global cardiovascular disease in the 21st century. In China, there are greater than 12 million patients with AF, and its incidence continues to rise. AF affects patients' quality of life and significantly increases the risks of mortality, stroke, heart failure, cognitive impairment, and dementia. In recent years, multiple clinical guidelines have expanded the indications for catheter ablation and raised its level of recommendation. Concurrently, there has been a rapid and sustained increase in the number of AF ablation procedures performed across China. Among these, radiofrequency catheter ablation remains the most used method. Consequently, the Chinese Heart Rhythm Society of the Chinese Society of Biomedical Engineering, in collaboration with 40 arrhythmia centers and 60 leading clinical experts specializing in AF catheter ablation, developed a comprehensive set of standards. These standards were developed based on extensive clinical experience accumulated in recent years and the latest national and international AF guidelines and consensus documents. They address five critical domains: periprocedural management, intra-atrial septal puncture, anatomical reconstruction and electroanatomic mapping, ablation, and complication identification and management. By providing a structured framework, these standards aim to guide AF catheter ablation practice, thereby enhancing procedural safety and efficacy.

Hospital readmissions following catheter ablation for atrial fibrillation with THERMOCOOL™ STSF/ THERMOCOOL™ ST catheter with CARTO™ 3 system versus TactiCath™ catheter with EnSite™ system.

Aim: Radiofrequency (RF) catheter ablation (CA) is a mainstay treatment for atrial fibrillation (AF). RF catheters with contact force (CF) sensing technology and electroanatomical mapping systems enable real-time assessment of catheter tip-tissue interface CF, facilitating individualized and precise CA. This study examined inpatient hospital readmissions in patients with AF treated with THERMOCOOL™ ST/ THERMOCOOL™ STSF catheter with the CARTO™ 3 System versus TactiCath™ catheter with the EnSite™ System. Materials & methods: Patients undergoing CA for AF between 1 July 2019 to 30 November 2021 were identified from the Premier Healthcare Database and grouped based on use of THERMOCOOL ST/STSF or TactiCath™. Study outcomes were all-cause, cardiovascular (CV)-, and AF-related inpatient readmission at 91-365-day post-CA. Inverse probability of treatment weighting of propensity scores balanced baseline patient, comorbidity and hospital characteristics. A weighted generalized estimating equation (GEE) model examined differences in readmission outcomes. Results: A total of 15,518 patients met inclusion criteria (THERMOCOOL ST/STSF, n=13,001; TactiCath™, n=2517). Patient characteristics were generally well-balanced after weighting. Patients treated with THERMOCOOL ST/STSF+CARTO 3 had a 20% lower likelihood of all-cause inpatient readmissions (7.8 vs 9.3%, chi-square p=0.041; odds ratio [OR]: 0.80, 95% confidence interval [CI]: 0.66-0.96, GEE p=0.019) and a 21% lower likelihood of CV-related inpatient readmission (5.2 vs 6.2%, chi-square p=0.133, OR: 0.79, 95% CI: 0.62-0.99, GEE p=0.043) in 91-365-days post-CA versus those treated with TactiCath™+ Ensite. No significant differences were observed for AF-related readmissions. Conclusion: Patients undergoing CA for AF treated with THERMOCOOL ST/STSF+CARTO 3 had a significantly lower risk of all-cause and CV-related inpatient hospital readmission versus those treated with TactiCath™+Ensite.

Posterior left atrial wall isolation for treatment of persistent atrial fibrillation during first-time catheter ablation: An updated systematic review and meta-analysis.

Although catheter ablation (CA) by mean of pulmonary vein isolation (PVI) is nowadays the mainstay treatment for atrial fibrillation (AF), its success-rate in persistent AF remains suboptimal. Results from studies evaluating whether adding posterior wall isolation (PWI) to PVI can increase the success-rate of CA in persistent AF have yielded conflicting data. The aim of this meta-analysis was to assess whether PWI plus PVI might be beneficial in patients with persistent AF. Electronic databases were searched for randomized control trials (RCTs) and observational studies that compared clinical outcomes between patients with persistent AF who underwent PVI with or without PWI. Fifteen studies, including a total of 3072 patients, were considered (1533 treated with PVI and 1539 with PWI + PVI). Comparing patients treated with or without PWI, no statistically significant difference was found in the risk of any atrial tachyarrhythmias recurrence after CA (RR 0.83; 95 % CI 0.66-1.03). The analyses detected a statistically significant reduction in the risk of AF in patients treated with PWI (RR 0.63; 95 % CI 0.48-0.84) balanced by a trend towards an increased risk of atrial flutter/atrial tachycardia (RR 1.51; 95 % CI 0.92-2.49). No statistically significant differences were identified in the risk of major procedural complications (RR 0.94; 95 % CI 0.50-1.78). According to our updated meta-analysis, the addition of PWI to PVI was not associated with a reduction of atrial arrhythmia recurrences. A reduction of the risk of AF recurrence and a trend towards an increased risk of atrial flutter/atrial tachycardia were identified.

Rhythm Control Better Prevents Stroke than Rate Control in Patients with Concomitant Hypertrophic Cardiomyopathy and Atrial Fibrillation: A Nationwide Population Based Cohort Study with Long-Term Follow-Up.

Atrial fibrillation (AF) increases the risks of stroke and mortality. It remains unclear whether rhythm control reduces the risk of stroke in patients with AF concomitant with hypertrophic cardiomyopathy (HCM). We identified AF patients with HCM who were ≥ 18 years old in the Taiwan National Health Insurance Database. Patients using antiarrhythmic medications for ≥ 30 defined daily doses (DDDs) or receiving catheter ablation for AF constituted the rhythm control group. Patients using rate control medications for ≥ 30 DDDs constituted the rate control group. A multivariable Cox regression model was used to evaluate the hazard ratio (HR) for adverse cardiovascular events. We enrolled a total of 178 patients with both AF and HCM without pre-existing cardiovascular diseases. Among them, 99 were in the rhythm control group and 79 were in the rate control group. After a follow-up period of 6.47 ± 0.98 years, the rhythm control group had a lower risk of stroke than the rate control group (adjusted HR: 0.380, p = 0.031) after adjusting for covariates including use of antithrombotic agents. After excluding patients receiving catheter ablation, the rhythm control group still had a lower risk of stroke than the rate control group (adjusted HR: 0.380, p = 0.037). In patients with AF and HCM, rhythm control with mainly pharmacological treatment better prevented stroke than rate control in long-term follow-up. The beneficial effect of lowering stroke risk through rhythm control was independent of oral anticoagulant use.

Impact of atrial fibrillation catheter ablation on the risk of progression of the disease towards a persistent form

Impact of atrial fibrillation catheter ablation on the risk of progression of the disease towards a persistent form

Takotsubo Syndrome Following Catheter Ablation for Atrial Fibrillation: A Systematic Review and Metasummary of Case Reports/Series.

Atrial fibrillation (AF) catheter ablation is safe and effective, though rare cases of takotsubo syndrome (TTS) have been observed without proven causation. This review synthesizes TTS following AF ablation case reports and series. Until October 2024, PubMed/Medline, SCOPUS, and Google Scholar were searched for AF ablation and TTS case reports and series. This study examines TTS incidence, clinical features, and prognosis after AF catheter ablation. Thirteen articles detailing 18 patients were included in the review. The study population had a mean age of 65 ± 9.18 years and 77.77% were female. Of the 18 patients, 6 patients (33.3%) underwent radiofrequency catheter ablation and 5 patients (27.7%) underwent cryoablation. All the patients developed TTS within 4 days of the procedure. Heart palpitations and breathlessness are predominant symptoms. Eight patients had T-wave inversion. Dyskinesia was the most prevalent echocardiography finding among the reported cases. Left ventricular ejection fraction was moderately reduced in 5 cases (35.7%) and severely reduced (left ventricular ejection fraction <30%) in 6 cases (42.8%). Of the 15 patients in whom a pattern of ballooning was reported, 13 patients had apical ballooning and 2 had atypical ballooning pattern. Of the 8 cases (44.44%) with complications, 1 had ventricular fibrillation and 2 patients had pulseless electrical activity. Left ventricular function is completely recovered among 17 patients whereas one patient died due to numerous cardiac electromechanical dissociation events. This systematic investigation highlights the need for TTS vigilance after AF ablation, especially in postmenopausal women having catheter ablation. More research is required to fully understand the prevalence, etiology, and risk factors of TTS after AF ablation.

Real-world evaluation of intracardiac echocardiography guided radio-frequency catheter ablation for atrial fibrillation: a retrospective cohort study

Intracardiac echocardiography (ICE) has been used to guide radio-frequency catheter ablation (RFCA) for better catheter navigation and less radiation exposure in treating atrial fibrillation (AF). This retrospective cohort study enrolled 227 AF patients undergoing ICE- or traditional fluoroscopy (TF)-guided RFCA for AF in a tertiary hospital. ICE was used more often in patients with atrial tachycardia [odds ratio (OR) 3.692, p = 0.062], a higher score of Hypertension, Abnormal renal/liver function, Stroke, Bleeding history or predisposition, Labile INR, Elderly, Drugs/alcohol concomitantly (OR 1.541, p = 0.050), or heart failure (OR 2.098, p = 0.156). Based on the comparisons of 47 propensity score-matched pairs from 156 patients only undergoing pulmonary vein isolation (PVI), patients using ICE exhibited a significantly higher success rate in the first transseptal puncture (100% vs. 87.2%, p = 0.041) and less radiation exposure [utilization of radiographic contrast agent (2.7 ml vs. 6.0 ml, p < 0.001), fluoroscopy time (5.7 min vs. 7.6 min, p = 0.026), and fluoroscopy dose (208.4 mGy vs. 332.3 mGy, p = 0.024)] than patients using TF. Other perioperative efficacy outcomes (PVI success, free from AF after RFCA and complications) showed no difference between the matched pairs. ICE can enhance procedural safety and efficiency of RFCA, particularly for more complex patient profiles, in real-world setting.

Pre-procedural TMAO as a predictor for recurrence of atrial fibrillation after catheter ablation

BackgroundNumerous studies have demonstrated the significance of trimethylamine-N-oxide (TMAO) in the progression of atrial fibrillation (AF). However, the association between TMAO and AF recurrence (RAF) post-catheter ablation is not yet fully understood. This study aims to elucidate the predictive capability of pre-procedural TMAO levels in determining RAF following catheter ablation (CA).MethodsThis study was conducted as a prospective, single-center observational study. Between June 2021 and June 2022, 152 patients from the Department of Cardiology at The Affiliated Huaian No. 1 People’s Hospital of Nanjing Medical University were enrolled. Baseline characteristics and serum TMAO levels were assessed for all participants. Patients with AF who underwent CA were monitored for recurrences of AF using electrocardiography (ECG) or 24-hour Holter monitoring during the follow-up period.ResultsThe study found that serum TMAO levels were significantly higher in persistent AF (PeAF) patients compared to those in sinus rhythm (SR) and paroxysmal AF (PaAF) patients (3.96 ± 1.69 vs. 1.81 ± 0.59, 3.02 ± 1.50 µM, P < 0.001 and P < 0.01, respectively). After a one-year follow-up, 29 (21.2%) AF patients experienced recurrence after CA. Multivariate Cox proportional hazards regression analysis revealed that pre-procedural serum TMAO was an independent predictor of recurrent AF (HR = 1.78, 95% CI = 1.43–2.21, P < 0.001). The receiver operating characteristic (ROC) curve analysis identified a cut-off value of 4.3µM for serum TMAO levels in predicting recurrent AF (area under the curve: 0.835, P < 0.001). The Kaplan-Meier plot demonstrated that patients with TMAO levels greater than 4.3µM had a significantly higher rate of recurrent AF (HR = 13.53, 95% CI = 6.19–29.56, P < 0.001).ConclusionPatients with AF exhibited elevated levels of circulating TMAO compared to patients with SR. The findings suggest a potential role of TMAO in the development of AF, with pre-procedural serum TMAO levels serving as a reliable predictor of recurrence of AF CA.

The Electroanatomic Volume of the Left Atrium as a Determinant of Recurrences in Patients with Atrial Fibrillation After Pulmonary Vein Isolation: A Prospective Study

Background/Objectives: Catheter ablation for atrial fibrillation (AF) is a well-established therapeutic approach for maintaining sinus rhythm, though its efficacy remains suboptimal in certain patients. The left atrium (LA) volume, commonly assessed through transthoracic echocardiography (TTE), is a recognized predictor of AF recurrence after pulmonary vein isolation (PVI). However, the complex three-dimensional structure of the LA makes precise measurement challenging with traditional TTE techniques. Electroanatomic mapping (EAM) offers a more accurate evaluation of LA geometry and volume, which may enhance the prediction of ablation outcomes. Methods: This prospective study included 197 patients with AF who were referred for PVI to our center (Hospital Universitario Central de Asturias, Spain) between 2016 and 2020. All participants underwent pre-ablation TTE and EAM to assess the electric active volume (EAV) of the LA. Clinical follow-up included regular Holter monitoring and electrocardiograms to detect AF recurrences. Results: The mean age was 56.3 ± 9.67 years, and 34% had persistent AF. The mean LA volumes measured by TTE and the EAV by EAM were 62.86 ± 15.58 mL and 126.75 ± 43.35 mL, respectively, with a moderate positive correlation (r = 0.49, p &lt; 0.001). AF recurrences were observed in 51.27% of patients over a 36 ± 15-month follow-up period. Cox regression analyses (univariate and multivariate), Kaplan–Meier curves and log-rank tests were used to illustrate freedom from atrial arrhythmia during follow-up. Both EAV by EAM and TTE volumes were significant predictors of AF recurrence in the univariate analysis (HR 1.002 [1.001–1.003], p = 0.033 and HR 1.001 [1.006–1.012], p &lt; 0.01, respectively). Among clinical variables, persistent AF was significantly associated with a higher risk of recurrence (HR 1.17 [1.096–1.268], p = 0.02). Conclusions: EAV of the LA assessment by EAM demonstrates a significant correlation with TTE measurements and is a predictor of AF post-ablation recurrence. In patients selected for catheter ablation, EAV by EAM provides additional insights that could contribute to therapeutic decision-making and risk stratification of AF recurrences.

Value of P-wave Parameters in Predicting Outcomes of Repeat Catheter Ablation for Paroxysmal Atrial Fibrillation.

Pulmonary vein isolation (PVI) has been established as an effective management option for symptomatic paroxysmal atrial fibrillation (PAF). We aimed to explore the role of P-wave parameters in a 12-lead electrocardiogram (ECG) in predicting the success of repeat PAF ablation. We enrolled consecutive patients who underwent a second AF ablation procedure for PAF in a UK tertiary center after an index ablation conducted between 2018 and 2019 and a repeat ablation up to 2021. A digital 12-lead ECG was recorded with a 1-50-Hz bandpass filter applied. P-wave duration (PWD), P-wave voltage (PWV), P-wave dispersion (PWDisp), and P-wave terminal force in V1 (PTFV1) were measured before and after the procedure. Changes were correlated with the 12-month clinical outcome. Procedural success was freedom from ECG-documented AF up to 12 months following ablation. Study criteria were satisfied by 72 patients, of which 43 (60%) had successful repeat PVI at 12 months. The mean age is 65, and 47 (65%) were males. The demographics were comparable between both study arms. PWD decreased after successful repeat ablations (136.7 to 124.6ms, p = 0.01) and failed repeat ablations (135.4 to 125.3ms, p = 0.009) without a significant change between both arms. PMV and PWDisp did not change significantly after both study arms. PTFV1 significantly decreased after successful repeat ablations (-3.1 to -4.4mm.s, p = 0.005) without a significant change after failed ablations (-2.9 to -2.7mm.s, p = 0.42). Changes were statistically significant between both arms (p = 0.004). PTFV1 reduction following the second AF ablation was correlated with successful repeat AF ablation at 12 months.

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 &lt; 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.

Long-term impact of atrial fibrillation catheter ablation on heart failure with preserved ejection fraction.

The efficacy of catheter ablation as a treatment approach for patients with concurrent atrial fibrillation (AF) and heart failure with preserved ejection fraction (HFpEF) has been inadequately investigated. This study's objective was to assess the effectiveness of atrial fibrillation ablation (AFA) in patients with heart failure with preserved ejection fraction. Utilizing the TriNetX research network, we identified individuals aged 18 and older with atrial fibrillation (AF) and concurrent heart failure with preserved ejection fraction (HFpEF) from January 1, 2010, to June 1, 2021. Patients were further classified based on their catheter ablation procedure, using Current Procedural Terminology codes. Following propensity-score matching, each cohort consisted of 9440 patients. The primary endpoint was all-cause mortality at two years and secondary outcomes during the 2-year follow-up encompassing readmissions for heart failure, AF, and stroke. In propensity-matched cohort, patients with AF and HFpEF who underwent AFA plus medical therapy had significantly lower all-cause mortality at two years than those who did not undergo AFA (hazard ratio (HR): 0.37, 95% CI: 0.34-0.40; P < 0.001) even after matching antiarrhythmic medications. At two years, secondary outcomes including HF readmissions (HR: 0.86 95% CI: 0.84-0.89; P < 0.001) and stroke readmissions (HR: 0.66 95% CI: 0.59-0.73; P < 0.001) were lower in the AFA group. AFA amongst AF patients with concomitant HFpEF showed a significant reduction in all-cause mortality. It also leads to significant reductions in readmissions due to HF and ischemic stroke at two years.

Vascular Cell Adhesion Molecule 1 in atrial fibrillation

ObjectiveAssessing whether serum Vascular Cell Adhesion Molecule 1(VCAM-1) concentration in the left atrial appendage(LAA) and the expression of VCAM-1 in LAA tissues are associated with the risk of atrial fibrillation-related stroke.MethodBlood samples were collected from atrial fibrillation(AF) patients scheduled for catheter ablation of AF, both from within the LAA and peripheral veins(PV). The serum concentration of VCAM-1 was quantitatively analyzed using ELISA. Additionally, LAA tissues were obtained from AF patients undergoing cardiac surgery, and immunohistochemical quantification was conducted to assess VCAM-1 expression in these tissues. Univariate analysis and multivariate logistic regression were performed to examine the association between VCAM-1 levels and the risk of atrial fibrillation-related stroke.ResultsA total of 146 patients scheduled for AF ablation and 34 patients scheduled for cardiac surgery were enrolled in this study. Among these two groups, there were 67 cases (45.9%) and 13 cases (38.2%) of AF patients who experienced strokes, respectively. Serum analysis revealed that in the AF group with strokes, the LAA serum VCAM-1 concentration was higher compared to the AF group without strokes (631.64 ± 143.48 pg/ml vs. 336.71 ± 201.66 pg/ml, P < 0.001). Similarly, the PV serum VCAM-1 concentration was higher in the AF group with strokes compared to the group without strokes (591.65 ± 128.23 pg/ml vs. 257.71 ± 157.92 pg/ml, P < 0.001). Additionally, both the AF group with strokes and the group without strokes exhibited higher LAA serum VCAM-1 concentrations compared to PV serum concentrations (631.64 ± 143.48 pg/ml vs. 591.65 ± 128.23 pg/ml, P = 0.041) and (336.71 ± 201.66 pg/ml vs. 257.71 ± 157.92 pg/ml, P = 0.004).Regarding left atrial tissue analysis, the AF group with strokes had a higher average optical density value (AOD) of VCAM-1 compared to the group without strokes (1.257 ± 0.147 vs. 1.093 ± 0.161, P < 0.001), indicating a higher expression level of VCAM-1 in the LAA in the AF group with strokes. In univariate analysis, LAA serum VCAM-1 concentration (OR = 1.15, P < 0.001), PV VCAM-1 concentration (OR = 1.11, P < 0.001), and LAA VCAM-1 AOD value (OR = 3.04, P = 0.021) were all associated with the risk of atrial fibrillation-related stroke. In the multivariate logistic regression analysis, LAA serum VCAM-1 concentration (OR = 1.17, P = 0.002) and PV VCAM-1 concentration (OR = 1.30, P = 0.034) were predictive of atrial fibrillation-related stroke. Specifically, left atrial appendage serum VCAM-1 concentration greater than 387.93 pg/ml and peripheral vein VCAM-1 concentration greater than 344.04 pg/ml were predictive of atrial fibrillation-related strokes.ConclusionsThe risk of stroke in AF is associated with VCAM-1, and elevated serum VCAM-1 concentrations in AF patients who experience strokes may be attributed not only to systemic inflammatory responses but also to increased VCAM-1 expression in LAA tissues. Serum VCAM-1 concentrations in AF patients can serve as predictive factors for atrial fibrillation-related stroke, with LAA serum VCAM-1 concentrations exceeding 387.93 pg/ml and peripheral vein VCAM-1 concentrations exceeding 344.04 pg/ml being predictive of atrial fibrillation-related strokes.

Catheter ablation in rate-controlled atrial fibrillation with severely reduced ejection fraction: intervention for irregularity-mediated cardiomyopathy.

Recent evidence suggests atrial fibrillation (AF) causes cardiomyopathy due to remodeling driven by both irregular rate and rhythm. Atrial fibrillation (AF) ablation in patients with reduced ejection fraction (EF) ≤ 35% has been shown to improve EF and mortality. It is unknown whether the benefits of AF ablation among patients with reduced EF are affected by the degree of pre-ablation rate control. To evaluate AF ablation echocardiographic outcomes for patients who have EF ≤ 35% with varying degrees of pre-ablation rate control. Single-center, retrospective study of patients with EF ≤ 35% undergoing first-time ablation of persistent AF. Primary analyses evaluated the degree to which pre-ablation rate control impacted echocardiographic outcomes. Rates of EF recovery to > 35% were compared at three different cutoffs: 110bpm, 90bpm, and 70bpm. A linear regression analysis was then performed to evaluate whether baseline heart rate (HR) predicted change in EF. Among 73 patients, the mean pre-ablation resting HR was 90 ± 25bpm, and baseline EF was 27 ± 7%. Patients experienced significant improvements in EF by mean + 14% ± 11% (p < 0.001). Post-ablation EF recovery occurred in 60% of patients. No differences in EF improvement were detected at HR control targets of ≤ 110bpm or ≤ 90bpm, while patients achieving HR ≤ 70bpm had less improvement in EF (+ 9% ± 9%) compared to those with HR above the cutoff (+ 16% ± 11%; p = 0.01). Linear regression analysis did not reveal baseline HR as a significant predictor of change in LVEF (slope = 0.09, r2 = 0.05, p = 0.07). Catheter ablation of persistent AF in patients with reduced EF frequently resulted in recovery in EF > 35%, irrespective of pre-ablation achieved rate control. While patients with HR > 70bpm experienced a greater improvement in EF compared to those ≤ 70bpm, patients with baseline HR below this target still experienced significant EF improvements. Further investigation into irregularity-mediated cardiomyopathy is warranted.

High-density mapping in catheter ablation for atrial fibrillation in Asia Pacific region: An observational study.

Few clinical studies of atrial fibrillation (AF) have focused on Asian patients; data are lacking on current mapping and ablation strategies in the Asia Pacific region (APAC). The HD Mapping Observational Study (NCT04022954) was designed to characterize electroanatomic mapping (EAM) with market-released high-density mapping (HDM) catheters in subjects with AF in APAC. Subjects undergoing HDM and indicated for radiofrequency ablation (RFA) to treat AF were prospectively enrolled in APAC. Data included mapping strategy and ablation targets. EAM was performed using one of two commercially available HDM catheters (Advisor™ HD Grid, Sensor Enabled™, Abbott [GRID] or Inquiry™ AFocus II™ Double Loop, Abbott [DL]). Procedure-related adverse events were collected. Two hundred subjects were enrolled at 15 centers: 164 with symptomatic paroxysmal (PAF) and 36 with symptomatic persistent (PersAF) AF for de novo ablation. GRID and DL were used in 186 and 14 cases, respectively. All subjects underwent voltage mapping, with conservative thresholds (low voltage ≤0.5 mV and very low voltage/electrical scar ≤0.1 mV) used in 60.2% and 35.4% of maps, respectively. Focal impulses, rotors, complex fractionated electrograms, and other substrate targets were each searched for in <3% of subjects. Median time to generate a map was 9.0 (Q1: 5.0, Q3: 13.0) minutes. Ablation strategy included pulmonary vein (PV) isolation in all, and non-PV triggers in 75/200 (37.5%) subjects. Five serious adverse events were reported. The study demonstrated an efficient strategy with the feasibility and safety of using HDM during AF ablation procedures in APAC.

Epigenetic regulation on left atrial function and disease recurrence after catheter ablation in atrial fibrillation

BackgroundGenetic variation and modifiable risk factors play a significant role in the pathogenesis of atrial fibrillation (AF). The influence of epigenetic modification on AF remains to be elucidated. We investigated the role of DNA methylation in the etiology of AF. Epigenetic evaluation was performed in 115 AF patients who underwent radiofrequency catheter ablation in a single institution. We measured methylation at approximately 850,000 bp cytosine-phosphate-guanine (CpG) sites in the 115 samples. The degree of methylation was compared across seven classification criteria: type of AF, late recurrence, impaired left atrium (LA) function, late gadolinium enhancement, LA diameter, LA volume, and flow velocity of the LA appendage.ResultsThe four most significantly methylated genes were DEFB104B, C3, TANC1, and TMEM9B. The DEFB104B gene (cg20223677 in the transcription start site), which encodes β-defensin 104B, was hypomethylated in three groups: AF patients with late recurrence, impaired LA function, and impaired LAA flow velocity. Enriched functional annotation of the differentially methylated datasets revealed that five out of the seven AF groups in this cohort were associated with genes involved in the cell movement of endothelial cell lines, sprouting angiogenesis by endothelial cell lines, or migration of endothelial cell lines.ConclusionsEpigenetic profiling revealed that epigenetic modification might affect important characteristics of AF. Our results suggest that the pathogenesis of AF might be affected by not only genetic variation or modifiable factors but also by epigenetic modulation.

Feasibility of Atrial Substrate Mapping During Atrial Pacing and Its Impact on the Omnipolar Voltage and the Peak-Frequency of Electrograms.

Atrial pacing maps are often used as substitutes for sinus rhythm (SR) maps to expedite mapping procedures. However, the impact of this method on electrophysiological parameters has not been systematically examined. This study aimed to elucidate the advantages and limitations of atrial pacing maps. In 21 patients undergoing catheter ablation for atrial fibrillation, left atrial (LA) substrate maps using an HD-grid catheter were performed during SR, and pacing from the sinus-node region with cycle lengths (CLs) of 300 ms (SN-P300) and 600 ms (SN-P600). Mapping time, omnipolar voltage, peak-frequency of electrograms, and global LA activation time were compared among the three maps. The SR-map more frequently required automap-setting changes (p < 0.01), and one SR-map was not completed due to CL-fluctuation. Compared to SR, mapping time significantly decreased (833 [702-1097] seconds for SR vs. 615 [530-700] seconds for SN-P600 and 463 [404-542] seconds for SN-P300, p < 0.01). Mean voltage and peak-frequency of electrograms significantly decreased in SN-P600 and SN-P300 (mean voltage: 2.5 [2.1-3.2] mV for SR vs. 2.3 [2.1-2.8] mV for SN-P600 and 2.2 [2.0-2.7] mV for SN-P300, p < 0.01; mean peak-frequency: 308 [299-325] Hz for SR vs. 303 [288-314] Hz for SN-P600 and 281 [258-295] Hz for SN-P300, p < 0.01). The wavefront collision site shifted in 3/20 (15%) between SR and SN-P600, remaing within 30° along the mitral annulus, but this shift reached 9/20 (45%) between SR and SN-P300, including one patient showing a shift up to 60°. SN-P maps provide faster, higher-resolution substrate maps, but the amplitude and frequency of electrograms may be reduced as the CL shortens. Maps with SN-P600 may be acceptable, maintaining electrophysiological information in SR.