Catheter Ablation Of Atrial Fibrillation Research Articles

Posterior wall isolation for persistent atrial fibrillation catheter ablation: an updated systematic review and meta-analysis

Abstract Background The ability of catheter ablation (CA) to prevent arrhythmic recurrences in patients with persistent atrial fibrillation (PeAF) remains suboptimal. In this context, the results of studies conducted with both thermal and non-thermal technologies, that evaluated the effect of adding electrical isolation of the posterior wall of the left atrium (PWI) to isolation of the pulmonary veins alone (PVI) have provided conflicting data. Purpose To compare the efficacy and safety of an ablative strategy with the addition of PWI to PVI versus PVI alone in patients with PeAF undergoing a first ablation procedure. Methods We searched electronic databases for observational studies and randomized controlled trials (RCTs) comparing PVI+PWI versus PVI alone as first CA procedure for PeAF, regardless of the technologies used. The efficacy outcomes were recurrence of any atrial tachyarrhythmias lasting more than 30 seconds, recurrence of atrial fibrillation (AF) and atrial flutter/atrial tachycardia (AFlu/AT). The safety outcome was relevant procedural complications defined as a composite of vascular complications, pericardial effusion or tamponade, phrenic nerve palsy, stroke, atrio-esophageal fistula, and death. The procedural time was compared between the ablation strategies studied. The software RevMan 5.4 was used to estimate the risk ratio (RR) and mean difference (MD) with the relative confidence intervals (CI), using a random-effect model. Results Thirteen studies (8 RCTs and 5 observational studies) counting a total of 2994 PeAF patients (1304 treated with PVI+PWI and 1690 with PVI alone; 1847 RF, 600 cryo and 547 PFA) were included in the analysis. Mean age was 65.2±4.1 years, and 26% were female. Mean follow-up period was 14.5±4.8 years. There were no significant differences in the risk of recurrence of any atrial tachyarrhythmias (RR 0.88; 95% CI 0.68-1.14) between the ablation strategies studied. Patients treated with PWI+PVI experienced a reduced risk of recurrence of AF (RR 0.67; 95% CI 0.48-0.94; p = 0.02) balanced by a trend towards increased risk of AFlu/AT (RR 1.74; 95% CI 0.99-3.06; p = 0.06) as compared with PVI alone strategy. No statistically significant differences in the risk of relevant procedural complication were identified between the studied groups (RR 0.94; 95% CI 0.50-1.78 – Fig. 2A). Procedural time was longer in the PWI+PVI group as compared with PVI alone (MD 30.63 min; 95% CI 8.60-52.65 min; p=0.006 – Fig. 2B). Conclusions Our metanalysis shows that, in patients with PeAF treated for the first time with CA, PWI+PVI versus PVI alone was not associated with a reduction of atrial tachyarrhythmias recurrence and required longer procedural times. Nonetheless, a reduction in the risk of AF recurrence and a trend towards an increased risk of AFlu/AT were identified. No differences in the risk of relevant procedural complications were found between the ablation strategies studied.Figure 2

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.

Clinical usefulness of digital twin guided virtual amiodarone test in patients with atrial fibrillation ablation

It would be clinically valuable if the efficacy of antiarrhythmic drugs could be simulated in advance. We developed a digital twin to predict amiodarone efficacy in high-risk atrial fibrillation (AF) patients post-ablation. Virtual left atrium models were created from computed tomography and electroanatomical maps to simulate AF and evaluate its response to varying amiodarone concentrations. As the amiodarone concentration increased in the virtual setting, action potential duration lengthened, peak upstroke velocities decreased, and virtual AF termination became more frequent. Patients were classified into effective (those with virtually terminated AF at therapeutic doses) and ineffective groups. The one-year clinical outcomes after AF ablation showed significantly better results in the effective group compared to the ineffective group, with AF recurrence rates of 20.8% vs. 45.1% (log-rank p = 0.031, adjusted hazard ratio, 0.37 [0.14-0.98]; p = 0.046). This study highlights the potential of a digital twin-guided approach in predicting amiodarone’s effectiveness and improving personalized AF management. Clinical Trial Registration Name: The Evaluation for Prognostic Factors After Catheter Ablation of Atrial Fibrillation: Cohort Study, Registration number: NCT02138695. The date of registration: 2014-05. URL: https://www.clinicaltrials.gov; Unique identifier: NCT02138695.

Surveillance of esophageal injury after atrial fibrillation catheter ablation.

Atrial-esophageal fistula following ablation procedures for atrial fibrillation (AF) remains a major concern. There is no standardized approach to minimize the risk and morbidity of this serious complication. The objective of this study was to present the 7-year experience of systematic endoscopic surveillance of esophageal injury after AF catheter ablation. This was a retrospective single-center registry of systematic endoscopic evaluations after consecutive AF ablation procedures performed from 2016 to 2022. A total of 677 AF ablation procedures with controlled esophagogastroduodenoscopy (EGD) were analyzed during that period. Most patients were male (71%) with paroxysmal AF (71%). Radiofrequency with electroanatomical mapping was the main ablation approach for 633 patients (93.5%). Esophageal temperature monitoring was performed using a single sensor in 220 patients (34.3%) and a multisensor probe in 296 patients (46%). Most of the patients presented no esophageal lesions (75,7%). Severe lesions (Kansas-city-classification KCC 2B) were found in 46 (6.8%) of them, requiring a new EGD in 7days. KCC2B lesions were persistent in 3 patients, 2 of whom had ulcers during healing and 1 patient with a deep ulcer of 10mm who was admitted to the hospital and underwent fasting and parenteral nutrition. The ulcer healed in the second week after the procedure. Both esophageal temperature monitoring strategies were equivalent at preventing thermal lesions. Additionally, a greater left atrium (LA) was associated with a lower incidence of esophageal ulcer (P = 0.028). Most of the lesions spontaneously healed. The incidence of esophageal injury after ablation was 24.3%. Most (72%) were mild lesions that required no therapeutic intervention. A larger left atrium (LA) was correlated with a lower incidence of thermal lesions. Early endoscopy can help diagnose severe esophageal lesions and may provide additional information for the surveillance of esophageal injury after AF ablation.

Efficacy and limitation of nonparoxysmal atrial fibrillation ablation in patients with heart failure with preserved ejection fraction.

Catheter ablation for atrial fibrillation (AF) reduces heart failure (HF) hospitalization in patients with HF with preserved ejection fraction (HFpEF). However, the long-term outcomes and subclinical HF after nonparoxysmal AF ablation in HFpEF patients have not been fully evaluated. One-hundred-ninety nonparoxysmal AF patients with left ventricular ejection fraction ≥50% who underwent first-time AF ablation were studied. HFpEF was diagnosed from a history of congestive HF and/or combined criteria of N-terminal pro-brain natriuretic peptide (NT-proBNP) concentration and transthoracic echocardiogram parameters, including average septal-lateral E/e' and tricuspid regurgitation peak velocity. Ninety-five patients with HFpEF (HFpEF group) were compared with 95 patients without HF (CNT group). Low voltage area (LVA) was defined as an area with a bipolar electrogram of <0.5 mV covering >5% of the total left atrial surface. The primary endpoint was a composite of death from any cause or hospitalization for worsening HF. The secondary endpoint was subclinical HFpEF defined from NT-proBNP concentration and average septal-lateral E/e' or tricuspid regurgitation peak velocity at 6-12 months after the procedure irrespective of the rhythm. Kaplan-Meier curves showed that the primary composite endpoint did not differ between the two groups (mean follow-up period 707 ± 75 days, log-rank p = 0.5330). However, significantly more patients in the HFpEF group reached the secondary endpoint (42 [44%] vs. 13 [14%], p < 0.0001). Multivariate analysis revealed that a high preablation NT-proBNP (odds ratio [OR] 1.001, 95% confidence interval [CI] 1.001-1.002, p = 0.0040) and the existence of LVA (OR 5.983, 95% CI 1.463-31.768, p = 0.0194) independently predicted the secondary endpoint in HFpEF patients. After nonparoxysmal AF ablation, mortality of HFpEF patients was not inferior compared to patients without coexisting HF. However, subclinical HF occasionally persisted especially in HFpEF patients with a high preprocedure NT-proBNP concentration and LVA.

Randomized Controlled Trial Comparing Training of Transseptal Puncture With or Without Intracardiac Echocardiography.

Intracardiac echocardiography (ICE) has been widely used in the catheter ablation of atrial fibrillation (AF). However, the value of ICE in the training of transseptal puncture (TSP) is unclear. ICE-Training Study was a single-center, parallel-group, unmasked, randomized controlled trial registered in ChineseClinicalTrials.gov. Participants were randomly assigned (1:1) to different groups (1) the ICE simulator training group (ICE-ST), in which TSP was trained and performed under the guidance of both ICE and x-ray; and (2) the conventional simulator training group (Con-ST), in which TSP was trained and performed only under the guidance of x-ray. The trainees need to undergo the training stage and the evaluation stage. From October 2022 to December 2022, 18 consecutive fellows (age 32.4±4.4years, 12 males) without experience of TSP were included. The training period (16.9±6.6 vs. 29.6±8.7 times, p=0.003) and the fluoroscopy time (120.3±25.3 vs. 189.3±40.2s, p<0.001) of the ICE-ST group was significantly shorter than that of the Con-ST group. No significant difference was found in the comprehensive performance of TSP in the ICE-ST group (composite score 96.7±5.7) and the Con-ST group (composite score 95.9±6.3, p=0.62), but the selection of TSP sites in the ICE-ST group was commonly better than that in the Con-ST group. ICE could improve the efficiency of TSP training and optimize the site of TSP to facilitate catheter manipulation in the ablation. ChineseClinicalTrials.gov identifier: ChiCTR2200058377.

Is sinus rhythm maintenance after repeat catheter ablation effective in patients with atrial fibrillation and heart failure with preserved ejection fraction?

Heart failure (HF) with preserved ejection fraction (HFpEF) and atrial fibrillation (AF) are associated with high morbidity and mortality. Recently, sinus rhythm (SR) maintenance (SRM) after catheter ablation (CA) of AF (AFCA) in HFpEF has shown to reduce adverse events as compared to medical treatment. However, it remains unclear whether SRM after a repeat CA for recurrent AF has the same effect as SRM after the initial CA in patients with AF and HFpEF. We studied 244 AF patients with HFpEF who maintained SR after repeat AFCA (repeat CA-SRM group, n = 54) and initial AFCA (initial CA-SRM group, n = 190). HFpEF were defined as HFA-PEFF score of 5 or 6 and left ventricular ejection fraction ≥ 50% before the initial CA. The primary endpoint was a composite of all-cause mortality, HF hospitalizations, or strokes within 3 years after the initial or repeat CA. The incidence of the primary endpoint was similar between the repeat CA-SRM and initial CA-SRM groups (3 of 54 [5.6%] vs. 8 of 190 [4.2%], p = .423 by a log-rank test). There was no significant difference in the 12-month HFA-PEFF score and the proportion of a 12-month HFA-PEFF score <5 between the repeat CA-SRM and the initial CA-SRM groups (5 [4,6] vs. 5 [4,6], p = .915, and 46% vs. 35%, p = .426, respectively). In patients with AF and HFpEF diagnosed by HFA-PEFF score, the primary endpoint of all-cause mortality, HF hospitalizations, and strokes was similar between the repeat CA-SRM and initial CA-SRM groups.

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

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

Factors influencing patient engagement in decision making for catheter ablation of atrial fibrillation: a cross-sectional survey.

Patient engagement in decision making could improve healthcare quality and health outcome, which has been emphasized in atrial fibrillation (AF) management guidelines. However, patients report relatively low level of engagement in decision making for catheter ablation (CA). Therefore, this study aims to explore the influencing factors of AF patient engagement in decision making for CA. A cross-sectional study was conducted. A total of 836 patients were recruited from six tertiary hospitals in Shanghai. Adapted version of the Control Preferences Scale, Chinese version of the All Aspects of Health Literacy Scale, Chinese version of the Facilitation of Patient Involvement Scale and the Atrial Fibrillation Knowledge Questionnaire were used to measure patient engagement in decision making, health literacy, perception of physician facilitation and AF knowledge, respectively. Of the 750 patients who returned valid questionnaires, 20.2% of the patients reported active engagement in decision making, 39.5% reported collaborative engagement, and 40.3% reported passive engagement. Compared with patients perceiving passive engagement, those with collaborative or active engagement were more likely to be female, have higher income, moderate EHRA class (II and III), higher perception of physician facilitation, higher health literacy and higher AF knowledge (P＜0.05 for all). The collaborative engagement group exhibited a shorter AF duration. The degree of patient engagement in CA decision making varied, with most perceiving passive engagement. Patient engagement in decision making was influenced by gender, income, duration of AF, EHRA class, perception of physician facilitation, health literacy and AF knowledge.

Association between ablation-induced baroreceptor reflex modification and procedure efficacy in patients with atrial fibrillation.

The autonomic nervous system (ANS) plays a significant role in atrial fibrillation (AF). Catheter ablation (CA) is a well-established treatment method for AF and significantly affects the ANS, including baroreceptor (BR) function. However, little is known about the changes in BR function caused by radiofrequency (RF) or cryoballoon energy (CB) and its impact on future AF recurrences. To assess 1-year efficacy of CA of AF in relation to BR function modification and type of ablation energy used. The study group consisted of 78 patients (25 females, mean age 58 ± 9 years) with paroxysmal AF and first CA (39 patients in the RF group and 39 in the CB group). The BR function was assessed non-invasively, using tilt testing before and after CA, and three BR parameters were calculated: event count (BREC) depicting overall BR activity, slope mean depicting BR sensitivity (BRS), and BR effectiveness index (BEI). The efficacy of CA was assessed during 1-year follow-up, which consisted of ambulatory visits and 24-h Holter ECG recordings at 3, 6, and 12 months after CA. The quality of life was assessed by using a dedicated scale [University of Toronto Atrial Fibrillation Severity Scale (AFSS)]. The two groups did not show differences in terms of clinical or demographic data. One-year follow-up was completed for 35 (89.7%) patients from the CB group and for 34 (87.2%) from the RF group. The rates of efficacy of CB and RF were similar [31/35 (88.6%) vs. 26/34 (76.5%), respectively]. After CA, the BR function decreased in both groups, with a significantly greater decrease in the CB group. The changes in BR parameters were similar in both responders and non-responders after CA in the whole group [BREC 10.0 (2.0-24.0) vs. 12.0 (4.0-21.5), p = 0.939; BRS 5.4 (3.7-6.5) vs. 4.8 (3.6-7.2), p = 0.809; BEI 24.8 (15.9-27.4) vs. 17.5 (8.9-27.5), p = 0.508, respectively]. According to the AFSS, the AF symptoms were significantly reduced in both groups to a similar extent. CA for AF significantly decreased the BR function, especially in patients undergoing CB. There was no correlation between CA-induced changes in BR parameters and ablation outcome.

Prediction of major intravascular hemolysis during pulsed electric field ablation of atrial fibrillation using a pentaspline catheter.

Pulsed electric field (PEF) has emerged as a promising energy source for catheter ablation of atrial fibrillation (AF). However, data regarding the in-vivo effect of PEF energy on erythrocytes during AF ablation procedures are scarce. This study aimed to quantify the impact of PEF energy on erythrocyte damage during AF ablation by assessing specific hemolytic biomarkers. A total of 60 patients (age: 68 years, males: 72%, serum creatinine: 91 µmol/L) with AF underwent catheter ablation of AF using PEF energy delivered by a multipolar pentaspline Farawave catheter (Farapulse, Boston Scientific, Inc.). Ablation beyond pulmonary vein isolation was performed at the operator's discretion. Peripheral venous blood was sampled for assessing the plasma levels of free hemoglobin (fHb), direct (conjugated) bilirubin, lactate dehydrogenase (LDH), and creatinine before, immediately after the ablation, and on the next day. Following the PEF ablation with duration of [median (interquartile range)] 75 (58, 95) min, with 74 (52, 92) applications and PVI only in 27% of patients, fHb, LDH, and direct bilirubin significantly increased, from 40 (18, 65) to 493 (327, 848) mg/L, from 3.1 (2.6, 3.6) to 6.8 (5.0, 7.9) µkat/L, and from 12 (9, 17) to 28 (16, 44) µmol/L, respectively (all p < .0001). A strong linear correlation was found between the peak fHb and the number of PEF applications (R = 0.81, p < .001). The major hemolysis (defined as fHb >500 mg/L) was predicted by the number of PEF applications with the corresponding area under the receiver operating characteristic curve of 0.934. The optimum cut-off value of >74 PEF applications predicted the major hemolysis with 89% sensitivity and 87% specificity. Catheter ablation of AF using PEF energy delivered from a pentaspline catheter is associated with significant intravascular hemolysis. More than 74 PEF applications frequently resulted in major hemolysis. However, the critical amount of PEF energy that may cause kidney injury in susceptible patients remains to be investigated.

Invasive management of atrial tachycardias using a novel lattice-tip catheter combining high-density mapping and dual ablation properties: initial real-world experience.

Invasive management of atrial tachycardias(ATs) requires proper diagnosis of the mechanism followed by elimination of the responsible substrate. A novel lattice-tip catheter with both high-density mapping and dual ablation properties(radiofrequency-RF/pulsed field ablation-PFA) has been recently introduced for catheter ablation of atrial fibrillation. We present the first study to assess its performance in the management of ATs (diagnostic and therapeutic). Patients with documented ATs were selected. Activation mapping was used for the establishment of the AT mechanism. Confirmation with entrainment was performed, whenever appropriate. Accuracy of the activation mapping in diagnosis, acute ablation efficacy, and procedural characteristics were the study endpoints. Twenty patients were included (12 cavotricuspid isthmus-dependent atrial flutters, 5 mitral flutters, 2 roof flutters, and 2 focal ATs). Proper diagnosis was established by activation mapping in all cases. The mean mapping time was 7.85 ± 3.06 min with 296.82 ± 150.9 mean mapping points/minute. The mean ablation time was 54.25 ± 42.97 s. Conversion to sinus rhythm during ablation was achieved in all cases with the exception of a roof flutter that converted to mitral flutter and a case of a parahisian AT in which ablation was not attempted. Patients that received ablation did not experience any arrhythmia recurrence in a mean follow up of 4.14 ± 0.91months. No major or minor complications occurred. The lattice-tip catheter and its dedicated electroanatomical mapping system provided sufficiently detailed activation mapping for the diagnosis of the AT mechanism. The delivered lesions were highly effective acutely, with no adverse events. However, limitations exist and should be acknowledged.

2024 European Heart Rhythm Association/Heart Rhythm Society/Asia Pacific Heart Rhythm Society/Latin American Heart Rhythm Society expert consensus statement on catheter and surgical ablation of atrial fibrillation

AbstractIn the last three decades, ablation of atrial fibrillation (AF) has become an evidence‐based safe and efficacious treatment for managing the most common cardiac arrhythmia. In 2007, the first joint expert consensus document was issued, guiding healthcare professionals involved in catheter or surgical AF ablation. Mounting research evidence and technological advances have resulted in a rapidly changing landscape in the field of catheter and surgical AF ablation, thus stressing the need for regularly updated versions of this partnership which were issued in 2012 and 2017. Seven years after the last consensus, an updated document was considered necessary to define a contemporary framework for selection and management of patients considered for or undergoing catheter or surgical AF ablation. This consensus is a joint effort from collaborating cardiac electrophysiology societies, namely the European Heart Rhythm Association, the Heart Rhythm Society, the Asia Pacific Heart Rhythm Society, and the Latin American Heart Rhythm Society

Anatomical Treatment Strategies for Persistent Atrial Fibrillation with Ethanol Infusion within the Vein of Marshall—Current Challenges and Future Directions

Currently, pulmonary vein isolation (PVI) is the gold standard in catheter ablation for atrial fibrillation (AF). However, PVI alone may be insufficient in the management of persistent AF, and complementary methods are being explored. One such method takes an anatomical approach—improving both its success rate and lesion durability may lead to improved treatment outcomes. An additional approach complementary to the anatomical one is also attracting attention, one that focuses on epicardial conduction. This involves ethanol ablation of the vein of Marshall (VOM) and can be very effective in blocking epicardial conduction related to Marshall structure; it is becoming incorporated into standard treatment. However, the pitfall of this “Marshall-PLAN”, a method that combines an anatomical approach with ethanol infusion within the VOM (Et-VOM), is that Et-VOM and other line creations are not always successfully completed. This has led to cases of AF and/or atrial tachycardia (AT) recurrence even after completing this lesion set. Investigating effective adjunctive methods will enable us to complete the lesion set with the aim to lower the rates of recurrence of AF and/or AT in the future.

A single-center outcome of choosing catheter ablation as the initial treatment in tachycardia–bradycardia syndrome and a new predictive factor for pacemaker implantation

BackgroundThe relationship between sinus node dysfunction and atrial fibrillation (AF) has been well known. The reversibility of sinus node dysfunction is indeed a critical factor in determining the treatment strategy in patients with tachycardia–bradycardia syndrome (TBS). We aimed to assess the clinical outcome of choosing catheter ablation as the initial treatment in tachycardia–bradycardia syndrome and predictive factors leading to the implantation of a permanent pacemaker (PPM) in these patients.MethodsPatients with TBS who had been taken AF catheter ablation from 2012 to 2021 were reviewed, and 113 patients were enrolled. Patients were divided into two groups based on whether a “sinus pause episode of more than 3 s unrelated to tachyarrhythmia” coexists (Group I, n = 20) or not (Group II, n = 93).ResultsCompared to Group II, baseline characteristics showed that Group I was comprised of more female gender (p = 0.043), with hypertension (p = 0.033), and with enlarged left atrium (p = 0.003). An average three-year follow-up found that eight patients (8/113, 7%) were implanted PPM (5/20, 25% in Group I vs. 3/93, 3.2% in Group II, p = 0.001). Using a multivariate model, a “sinus pause episode unrelated to tachyarrhythmia” was strongly associated with PPM implantation after catheter ablation in patients with TBS (HR 6.765, 95% CI 1.355–33.763, p = 0.020). Only four out of 113 patients (3.5%) progressed to persistent or permanent AF.ConclusionsAfter catheter ablation as the initial treatment in TBS, only 7% underwent PPM implantation, and an isolated sinus pause was a predictive factor for requiring PPM implantation. In addition, even in patients who undergo catheter ablation with subsequent PPM implantation, we can expect to improve the clinical outcome associated with a reduced AF burden.

Combined Catheter Ablation of Atrial Fibrillation and Premature Ventricular Complexes

Combined Catheter Ablation of Atrial Fibrillation and Premature Ventricular Complexes

Impact of Catheter Ablation on AtrialFibrillation Burden and Symptomsin Patients With HypertrophicCardiomyopathy.

Atrial fibrillation (AF) is more common in patients with hypertrophic cardiomyopathy (HCM) and is often highly symptomatic. The impact of catheter ablation (CA) may be under-reported when evaluated by long-term freedom from any atrial arrhythmia. This study aims to evaluate whether CA of AF in patients with HCM would significantly reduce AF burden and improve symptoms. A multicenter registry was established to enroll HCM patients with pre-existing cardiac implantable electronic devices undergoing CA of AF between 2017 and 2021. The first AF recurrence and burden 12months before and after CA were determined. Eighty-one HCM patients with cardiac implantable electronic devices underwent CA of AF. Patients were followed-up for a minimum of 1-year (35 [Q1-Q3 range: 23-50] months). AF was paroxysmal in 38 of 81 (46.9%) patients and burden pre-CA was 27.0% (Q1-Q3 range: 3.0% to 99.0%). Thirty-five (43.2%) patients had AF/atrial tachycardia recurrence within 12months. AF burden reduced after CA to 0.5% (Q1-Q3 range: 0.0% to 11.1%) (P=0.001); a 95% CI (range: 13.8% to 100%) relative reduction. European Hearth Rhythm Association class improved by 1.8 ± 1.3 classes (P<0.001). Of those with AF/atrial tachycardia recurrence, the reduction in AF burden was -33.7% (Q1-Q3 range: -88.9% to -13.8%) (P< 0.001) and 20 (57.1%) patients reported symptomatic improvement by≥1 European Hearth Rhythm Association class. AF burden reduction was associated with symptomatic improvement. (r=-0.67; P< 0.001) CONCLUSIONS: AF recurrence is common after CA in HCM patients, but this may under-represent the impact of CAinthis cohort. CA significantly reduced AF burden and improved symptoms. A comprehensive evaluation of AFburden,symptoms, and hard endpoints is needed to determine the utility of CA in this context.

Lesion characteristics using high-frequency low-tidal volume ventilation versus standard ventilation during ablation of paroxysmal atrial fibrillation.

High-frequency low-tidal-volume (HFLTV) ventilation during radiofrequency catheter ablation (RFCA) for paroxysmal atrial fibrillation (PAF) has been shown to be superior to standard ventilation (SV) in terms of procedural efficiency, acute and long-term clinical outcomes. Our study aimed to compare ablation lesions characteristics utilizing HFLTV ventilation versus SV during RFCA of PAF. A retrospective analysis was conducted on patients who underwent pulmonary vein isolation (PVI) for PAF between August 2022 and March 2023, using high-power short-duration ablation. Thirty-five patients underwent RFCA with HFLTV ventilation and were matched with another cohort of 35 patients who underwent RFCA with SV. Parameters including ablation duration, contact force (CF), impedance drop, and ablation index were extracted from the CARTONET database for each ablation lesion. A total of 70 patients were included (HFLTV = 35/2484 lesions, SV = 35/2830 lesions) in the analysis. There were no differences in baseline characteristics between the groups. While targeting the same ablation index, the HFLTV ventilation group demonstrated shorter average ablation duration per lesion (12.3 ± 5.0 vs. 15.4 ± 8.4 s, p < .001), higher average CF (17.0 ± 8.5 vs. 10.5 ± 4.6 g, p < .001), and greater impedance reduction (9.5 ± 4.6 vs. 7.7 ± 4.1 ohms, p < .001). HFLTV ventilation group also demonstrated shorter total procedural time (61.3 ± 25.5 vs. 90.8 ± 22.8 min, p < .001), ablation time (40.5 ± 18.6 vs. 65.8 ± 22.5 min, p < .001), and RF time (15.3 ± 4.8 vs. 22.9 ± 9.7 min, p < .001). HFLTV ventilation during PVI for PAF was associated with improved ablation lesion parameters and procedural efficiency compared to SV.

Varying Effect of AF Ablation in Patients with HFpEF according to CHA2DS2-VASc score

The impact of comorbidity burden on outcomes of radiofrequency catheter ablation (RFCA) for atrial fibrillation (AF) in patients with heart failure and preserved ejection fraction (HFpEF) remains unclear. To evaluate how comorbidity burden influences the association between RFCA and cardiovascular outcomes in AF patients with HFpEF. AF patients with HFpEF from the prospective China-AF cohort, recruited between August 2011 and December 2020, were categorized into two groups based CHA2DS2-VASc score: low comorbidity burden (score ≤ 4) and high comorbidity burden (score > 4). The associations between RFCA and cardiovascular outcomes and interaction effects of comorbidity burden on these associations were assessed. Among 1,700 patients with a median follow-up of 65.9 months, those in the low comorbidity burden group who received RFCA had a lower risk of composite events (cardiovascular death and ischemic stroke/TIA) [adjusted hazard ratio (aHR): 0.35, 95% CI, 0.21-0.59] and all-cause death [aHR: 0.31, 95% CI, 0.17-0.54] compared to those without RFCA. However, significant associations were not observed in the high comorbidity burden group. The differences between low and high comorbidity burden groups were significant, with interaction effects noted between comorbidity burden and RFCA for cardiovascular death (Pinteraction=0.045) and ischemic stroke/TIA (Pinteraction=0.010). RFCA was associated with a reduced risk of AF recurrence in both comorbidity burden groups. RFCA for AF is associated with reduced AF recurrence and improved cardiovascular outcomes in patients with HFpEF. However, these benefits may be limited for patients with a CHA2DS2-VASc score > 4 (high comorbidity burden).

Characterization and Clinical Significance of Hemolysis After Pulsed Field Ablation for Atrial Fibrillation: Results of a Multicenter Analysis.

Pulsed field ablation (PFA) is increasingly used in clinical practice for the treatment of atrial fibrillation. While the susceptibility of erythrocytes to electroporation is well established, the effect of cardiac PFA technologies on hemolysis has remained underreported. The aim of this study was to investigate the incidence, severity, and clinical impact of PFA-induced hemolysis. We included n=145 patients undergoing atrial fibrillation catheter ablation with a pentaspline PFA catheter (biphasic, bipolar pulses of 2 kV) and n=70 patients receiving radiofrequency ablation (40-90 W) at 4 high-volume European centers. The lesion set comprised pulmonary vein isolation for paroxysmal atrial fibrillation and pulmonary vein isolation±additional lesions for persistent atrial fibrillation. Hemolysis and renal function biomarkers were analyzed in blood samples at baseline, at the end of ablation, and 24 hours after the procedure. Baseline characteristics were well balanced between groups (overall mean, 65.7±9.4 years; 69.3% male). The ablation procedures comprised a mean of 61.6±27.4 PFA deliveries and 26.3±15.0 minute RF duration. Hemolysis was detected in 94.3% versus 6.8% of patients after PFA versus radiofrequency ablation (P<0.001): PFA was associated with significantly lower haptoglobin levels (0.5±0.4 versus 1.0±0.4 g/L), while free plasma hemoglobin (592.8±330.6 versus 147.8±183.0 mg/L), bilirubin (21.3±11.3 versus 14.8±8.8 µmol/L), and LDH (lactate dehydrogenase, 352.7±115.7 versus 253.2±56.5 U/L) were significantly higher after PFA versus radiofrequency ablation (all P<0.001). Hemolysis correlated with the number of PFA deliveries (r=0.62 [95% CI, 0.33-0.80]; P<0.001), with the highest severity occurring ≥54 PFA deliveries. After PFA, hemoglobinuria occurred in 36.4%, while creatinine increase was higher in patients with baseline glomerular filtration rate <50 mL/min versus baseline glomerular filtration rate >50 mL/min (Δcrea, 27.0±103.1 versus -0.2±12.1 µmol/L; P=0.010). Intravascular hemolysis is a frequent finding after PFA and increases with the number of PFA deliveries. Until the clinical impact of PFA-associated hemolysis is fully elucidated, a careful titration of PFA deliveries during the ablation procedure is warranted.