Second-generation laser balloon ablation for the treatment of atrial fibrillation assessed by continuous rhythm monitoring: the LIGHT-AF study

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

In 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 (HRS), the Asia Pacific HRS, and the Latin American HRS.

Pulsed field ablation technology for pulmonary vein and left atrial posterior wall isolation in patients with persistent atrial fibrillation

INTRODUCTION

Limited data exist on pulsed-field ablation (PFA) in patients with persistent atrial fibrillation (PeAF) undergoing left atrial posterior wall isolation (LAPWI).

METHODS

The Advanced TecHnologies For SuccEssful AblatioN of AF in Clinical Practice (ATHENA) prospective registry included consecutive patients referred for PeAF catheter ablation at 9 Italian centers, treated with the FARAPULSETM-PFA system. The primary efficacy and safety study endpoints were the acute LAPWI rate, freedom from arrhythmic recurrences and the incidence of major periprocedural complications. Patients undergoing pulmonary vein isolation (PVI) alone, PWI + LAPWI and redo procedures were compared.

RESULTS

Among 249 patients, 21.7% had long-standing PeAF, 79.5% were male; mean age was 63 ± 9 years. LAPWI was performed in 57.6% of cases, with 15.3% being redo procedures. Median skin-to-skin times (PVI-only 68 [60-90] vs. PVI + LAPWI 70 [59-88] mins) did not differ between groups. 45.8% LAPWI cases were approached with a 3D-mapping system, and 37.3% with intracardiac echocardiography. LAPWI was achieved in all patients by means of PFA alone, in 88.8% cases at first pass. LAPWI was validated either by an Ultrahigh-density mapping system or by recording electrical activity + pacing maneuvers. No major complications occurred, while 2.4% minor complications were detected. During a median follow-up of 273 [191-379] days, 41 patients (16.5%) experienced an arrhythmic recurrence after the 90-day blanking period, with a mean time to recurrence of 223 ± 100 days and no differences among ablation strategies.

CONCLUSION

LAPWI with PFA demonstrates feasibility, rapidity, and safety in real-world practice, offering a viable alternative for PeAF patients. LAPWI is achievable even with a fluoroscopy-only method and does not significantly extend overall procedural times.

National workflow experience with pulsed field ablation for atrial fibrillation: learning curve, efficiency, and safety

BACKGROUND

Recent data on pulsed field ablation (PFA) for atrial fibrillation (AF) ablation suggest a progressive reduction in procedural times. Real-world data regarding the relationship between the learning curve of PFA and clinical outcomes are scarce. The objective was to evaluate the PFA learning curve and its impact on acute outcomes.

METHODS

Consecutive patients undergoing AF ablation with the FARAPULSE™ PFA system were included in a prospective, non-randomized multicenter study. Procedural times were stratified on the operators' learning curve. Comparative analysis of skin-to-skin time was conducted with radiofrequency (RF) and cryoablation (CB) pulmonary vein isolation (PVI) procedures performed by the same operators in the previous year.

RESULTS

Among 752 patients, 35.1% were females, and 66.9% had paroxysmal AF; mean age was 62.2 ± 10 years. A total of 62.5% of procedures were performed by operators with > 20 PFA procedures. Both time to PVI (25.6 ± 10 min vs 16.5 ± 8, p < 0.0001) and fluoroscopy time (19.8 ± 8 min vs 15.9 ± 8 min, p = 0.0045) significantly improved after 10 associated with consistent linear trend towards procedural time reduction (R2 0.92-0.68 across various procedural metrics). Current PFA skin-to-skin time was lower than the historical skin-to-skin one in 217 (62.4%) procedures; it was similar in 112 (32.2%) cases and higher than the historical skin-to-skin one in 19 (5.5%). No major complications were reported.

CONCLUSIONS

In this nationwide multicentric experience, the novel PFA system proved to be fast, safe, and acutely effective in both paroxysmal and persistent AF patients. The learning curve appears to be rapid, as improvements in procedural parameters were observed after only a few procedures.

CLINICAL TRIAL REGISTRATION

Advanced TecHnologies For SuccEssful AblatioN of AF in Clinical Practice (ATHENA). URL: http://clinicaltrials.gov/ Identifier: NCT05617456.

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

In 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.

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

In 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 .

Early Clinical Outcomes and Advantages of a Novel-Size Adjustable Second-Generation Cryoballoon: A Proof-of-Concept Study

(1) Background/Objective Balloon-guided catheter ablation (CA) has emerged as an alternative option for atrial fibrillation (AF) management. The recent introduction of a novel-size adjustable second-generation cryoballoon (CB) system offers innovations, but clinical outcomes remain unexplored. This study aims to assess the acute performance of the POLARx FIT™ CB system in AFCA. (2) Methods: Consecutive patients undergoing AF ablation with the POLARx FIT™ CB system in our center were included. The primary outcome was the rate of 31 mm balloon-size utilization, with secondary outcomes including acute pulmonary vein isolation (PVI) rate, periprocedural complications, and in-hospital AF recurrences. (3) Results: Twenty-four patients with a mean age of 59.5 years, predominantly male (87.5%), and exhibiting paroxysmal AF (91.7%) were enrolled. Procedural characteristics demonstrated a high acute success rate (100% PV isolation) with a favorable safety profile. Notably, the 31 mm CB configuration was utilized in 51% of applications, showcasing its adaptability in challenging anatomies. No major complications occurred, with two patients experiencing in-hospital self-limiting AF recurrences. (4) Conclusions: This study represents the first comprehensive assessment of the POLARx FIT™ CB system in AF ablation. While acknowledging the study's limitations, this novel CB emerges as a promising tool, warranting further exploration in larger studies with extended follow-up periods.

Association of Prediabetes and Recurrent Stroke in Atrial Fibrillation Patients: A Population-Based Analysis of Hospitalizations and Outcomes

Prediabetes is a risk factor for ischemic stroke in atrial fibrillation (AF) patients, yet, its impact on recurrent stroke in AF patients remains understudied. Using the 2018 National Inpatient Sample, we investigated the link between Prediabetes and recurrent stroke in AF patients with prior stroke or transient ischemic attack (TIA). Among 18,905 non-diabetic AF patients, 480 (2.5%) had prediabetes. The prediabetic group, with a median age of 78, exhibited a two-fold higher risk of recurrent stroke compared to the non-prediabetic cohort (median age 82), as evidenced by both unadjusted (OR 2.14, 95% CI 1.72-2.66) and adjusted (adjusted for socio-demographics/comorbidities, OR 2.09, 95% CI 1.65-2.64, p < 0.001). The prediabetes cohort, comprising more male and Black patients, demonstrated associations with higher Medicaid enrollment, admissions from certain regions, and higher rates of hyperlipidemia, smoking, peripheral vascular disease, obesity, and chronic obstructive pulmonary disease (all p < 0.05). Despite higher rates of home health care and increased hospital costs in the prediabetes group, the adjusted odds of all-cause mortality were not statistically significant (OR 0.55, 95% CI 0.19-1.56, p = 0.260). The findings of this study suggest that clinicians should be vigilant in managing prediabetes in AF patients, and strategies to prevent recurrent stroke in this high-risk population should be considered.

Atrial fibrillation recurrences during the blanking period after catheter ablation with the laser balloon technique

INTRODUCTION

Regardless of the catheter ablation (CA) for atrial fibrillation (AF) strategy, the role of early recurrences during the blanking period (BP) is still unclear. Our aim was to evaluate atrial tachyarrhythmias (ATAs) recurrences during the BP after CA with the laser-balloon (LB) technique.

METHODS

Consecutive patients undergoing LBCA were enrolled. Primary outcome of the study was the overall crude ATA recurrence rate during the BP. ATA recurrences after the BP and in-hospital readmissions during the BP were deemed secondary outcomes.

RESULTS

Two hundred and twenty-four patients underwent CA with the LB. Median age was 63.0 (55.5-69.5) years and 74.1% were males. 28.6% were persistent AF patients, and 34.8% of patients were followed up with a loop recorder. 15.6% of patients experienced at least an ATA recurrence during the BP. Male sex, chronic heart failure, persistent AF, and recurrences during the BP were found to be associated with long-term ATA recurrences. Recurrences during the BP remained associated with the outcome of interest at multivariate analysis (hazard ratio [HR] = 12.393, 95% confidence interval [95% CI] = 3.699-41.865, p < .001). An association over time was found between early and late recurrences, with 73.7%, 45.5%, and 10.8% of patients presenting with recurrences at 1-, 2-, and 3-month follow-up being free from recurrences after the BP, respectively. 8.0% of patients were readmitted during the BP: 4.5% for AF electrical cardioversion, and 1.8% for CA of other atrial arrhythmias; no redo CA was performed.

CONCLUSION

After adjusting for confounders, ATA recurrences during the BP represent the most significant predictor of ATA recurrences after the BP, regardless of AF pattern.

Safety and Efficacy of Uninterrupted Oral Anticoagulation in Patients Undergoing Catheter Ablation for Atrial Fibrillation with Different Techniques

BACKGROUND

The safety and efficacy of an uninterrupted direct anticoagulation (DOAC) strategy during catheter ablation (CA) for atrial fibrillation (AF) has not been fully investigated with different ablation techniques.

METHODS

We evaluated consecutive AF patients undergoing catheter ablation with three different techniques. All patients were managed with an uninterrupted DOAC strategy. The primary endpoint was the rate of periprocedural thromboembolic and bleeding events. The secondary endpoints of the study were the rate of MACE and bleeding events at one-year follow-up.

RESULTS

In total, 162 patients were enrolled. Overall, 53 were female and the median age was 60 [55.5-69.5] years. The median CHA2DS2-VASc and HAS-BLED scores were 2 [1-4] and 2 [1-2], respectively. In total, 16 patients had a past stroke or TIA while 11 had a predisposition or a history of bleeding. The CA procedure was performed with different techniques: RF 43%, cryoballoon 37%, or laser-balloon 20%. Overall, 35.8% were on rivaroxaban, 20.4% were on edoxaban, 6.8% were on apixaban, and 3.7% were on dabigatran. All other patients were all naïve to DOACs; the first anticoagulant dose was given before the ablation procedure. As for periprocedural complications, we found three groin hematomas not requiring interventions, one ischemic stroke, and one systemic air embolism (the last two likely due to several catheter changes through the transeptal sheath). Five patients reached the secondary endpoints: one patient for a myocardial infarction while four patients experienced minor bleeding during 1-year follow-up.

CONCLUSIONS

Our results corroborate the safety and the efficacy of uninterrupted DOAC strategy in patients undergoing CA for AF, regardless of the ablation technique.

Efficacy and safety of visually guided laser balloon versus cryoballoon ablation for paroxysmal atrial fibrillation: a systematic review and meta-analysis

Background

Newly developed catheter ablation (CA) techniques, such as laser balloon ablation (LBA) and cryoballoon ablation (CBA), have been introduced in recent years and emerged as valuable alternatives to conventional radiofrequency CA strategies for paroxysmal atrial fibrillation (PAF) patients. However, evidence comparing LBA and CBA remain controversial. Thus, we conducted this meta-analysis to assess the efficacy and safety between these two techniques.

Methods

Scientific databases (PubMed, Embase) and relevant websites (the Cochrane Library, ClinicalTrials.gov) were systematically searched from inception to March 2023. The primary outcomes of interest were the AF recurrence and the procedure-related complications. Secondary outcomes included procedural time, fluoroscopy time, and left atrial (LA) dwell time.

Results

Seven clinical trials with a total of 637 patients were finally enrolled. No significant differences were found between LBA and CBA in terms of AF recurrence [16.3% vs. 22.7%, odds ratio (OR) = 0.66, 95% confidence interval (CI): 0.42-1.05, p = 0.078] or total procedural-related complications (8.4% vs. 6.4%, OR = 1.33, 95% CI: 0.71-2.51, p = 0.371). LBA had a significantly longer procedural time [weighted mean difference (WMD) = 38.03 min, 95% CI: 13.48-62.58 min, p = 0.002] and LA dwell time (WMD = 46.67 min, 95% CI: 14.63-78.72 min, p = 0.004) than CBA, but tended to have shorter fluoroscopy time.

Conclusions

LBA and CBA treatment have comparable efficacy and safety for PAF patients. LBA was associated with longer procedural and LA dwell times compared with CBA. Further large-scale studies are warranted to compare these two techniques with the newest generations.Systematic Review Registration: https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=426513, identifier (CRD42023426513).

Progress in atrial fibrillation ablation during 25 years of Europace journal

The first edition of Europace journal in 1999 came right around the time of the landmark publication of the electrophysiologists from Bordeaux, establishing how elimination of ectopic activity from the pulmonary veins (PVs) resulted in a marked reduction of atrial fibrillation (AF). The past 25 years have seen an incredible surge in scientific interest to develop new catheters and energy sources to optimize durability and safety of ablation, as well as study the mechanisms for AF and devise ablation strategies. While ablation in the beginning was performed with classic 4 mm tip catheters that emitted radiofrequency (RF) energy to create tissue lesions, this evolved to using irrigation and contact force (CF) measurement while increasing power. Also, so-called single-shot devices were developed with balloons and arrays to create larger contiguous lesions, and energy sources changed from RF current to cryogenic ablation and more recently pulsed field ablation with electrical current. Although PV ablation has remained the basis for every AF ablation, it was soon recognized that this was not enough to cure all patients, especially those with non-paroxysmal AF. Standardized approaches for additional ablation targets have been used but have not been satisfactory in all patients so far. This led to highly technical mapping systems that are meant to unravel the drivers for the maintenance of AF. In the following sections, the development of energies, strategies, and tools is described with a focus on the contribution of Europace to publish the outcomes of studies that were done during the past 25 years.

Rhythm vs. Rate Control in Patients with Postoperative Atrial Fibrillation after Cardiac Surgery: A Systematic Review and Meta-Analysis

BACKGROUND

Postoperative atrial fibrillation (POAF) is the most common complication after cardiac surgery; it is associated with morbidity and mortality. We undertook this review to compare the effects of rhythm vs. rate control in this population.

METHODS

We searched MEDLINE, Embase and CENTRAL to March 2023. We included randomized trials and observational studies comparing rhythm to rate control in cardiac surgery patients with POAF. We used a random-effects model to meta-analyze data and rated the quality of evidence using GRADE.

RESULTS

From 8,110 citations, we identified 8 randomized trials (990 patients). Drug regimens used for rhythm control included amiodarone in four trials, other class III anti-arrhythmics in one trial, class I anti-arrhythmics in four trials and either a class I or III anti-arrhythmic in one trial. Rhythm control compared to rate control did not result in a significant difference in length of stay (mean difference -0.8 days; 95% CI -3.0 to +1.4, I² = 97%), AF recurrence within 1 week (130 events; risk ratio [RR] 1.1; 95%CI 0.6-1.9, I² = 54%), AF recurrence up to 1 month (37 events; RR 0.9; 95%CI 0.5-1.8, I² = 0%), AF recurrence up to 3 months (10 events; RR 1.0; 95%CI 0.3-3.4, I² = 0%) or mortality (25 events; RR 1.6; 95%CI 0.7-3.5, I² = 0%). Effect measures from seven observational studies (1428 patients) did not differ appreciably from those in randomized trials.

CONCLUSIONS

Although atrial fibrillation is common after cardiac surgery, limited low-quality data guide its management. Limited available evidence suggests no clear advantage to either rhythm or rate control. A large-scale randomized trial is needed to inform this important clinical question.

Healthcare Utilization and Outcomes in Atrial Fibrillation Patients Treated by Drug Therapy versus a Catheter Ablation Strategy-A Middle European Propensity Score Matched Cohort Study

BACKGROUND AND AIMS

Atrial fibrillation (AF) is the most prevalent arrhythmia, associated with increased mortality and morbidity and causing relevant costs. Treatment options consist of catheter ablation (PVI) and rate or rhythm control drugs (non-PVI).

METHODS

We analyze inpatient and outpatient data from the Upper Austrian Health Insurance Fund. Data of patients with a first hospitalization for AF in the years 2005 to 2018 were examined, using propensity score matching (PSM) including all CHA₂DS₂-VASc variables and working "collar".

RESULTS

Out of 21,791 AF patients, PSM identified 1013 well-matching pairs (PVI and non-PVI). Over a ten-year period, the PVI treatment strategy group reveals significantly higher inpatient and outpatient expenditures (€2200/year). Positive economic effects can be demonstrated by a 5.1 percentage points (pp) higher employment rate and fewer retirements (7.6pp). Of utmost important is the 5.8pp all-cause mortality reduction over 10 years in the PVI treatment strategy.

CONCLUSIONS

A PVI based treatment strategy results in higher healthcare expenditures vs. drug therapy alone. Most of these higher costs were caused by the PVI procedures during this period. Thus, more effective and efficient methods are needed to further reduce costs for the intervention and prevent repeat procedures. The benefit of a PVI treatment strategy is seen in higher employment rates, which are crucial from a societal perspective and should be a strong argument for caregivers. We show a significant reduction in all-cause mortality, which we partly attribute to the PVI procedure itself, to a stricter risk factor assessment and treatment, and a tighter medical adherence.

Clinical Management of New-Onset Atrial Fibrillation in COVID-19 Patients Referred to a Tertiary Cardiac Arrhythmia Center after Hospital Discharge

Background: Available reports on the post-discharge management of atrial fibrillation (AF) in COVID-19 patients are scarce. The aim of this case series was to describe the clinical outcomes of new-onset AF in COVID-19 patients referred to a tertiary cardiac arrhythmia center after hospital discharge. Methods: All consecutive patients referred to our center for an ambulatory evaluation from 18 May 2020 to 15 March 2022 were retrospectively screened. Patients were included in the current analysis if new-onset AF was diagnosed during hospitalization for COVID-19 and then referred to our clinic. Results: Among 946 patients, 23 (2.4%) were evaluated for new-onset AF during COVID-19. The mean age of the study cohort was 71.5 ± 8.1 years; 87.0% were male. Median time from COVID-19 discharge and the first ambulatory evaluation was 53 (41.5–127) days; median follow-up time was 175 (83–336) days. At the in-office evaluation, 14 (60.9%) patients were in sinus rhythm, and nine patients were in AF. In 13.0% of cases, oral anticoagulation was stopped according to CHADS-VASc. Eight patients in AF were scheduled for electrical cardioversion; one patient was rate-controlled. Four patients were treated with catheter ablation (CA) during follow-up. Two post-cardioversion AF recurrences were detected during follow-up, while no recurrences were diagnosed among patients who underwent CA. Conclusion: Our data suggest that AF may not be considered as a simple bystander of the in-hospital COVID-19 course. Management of new-onset AF in post-COVID-19 patients referred to our clinic did not significantly differ from our usual practice, both in terms of long-term oral anticoagulation and in terms of rhythm control strategy.

Hospital outcomes of patients receiving catheter ablation of atrial fibrillation, left atrial appendage closure, or both

BACKGROUND

Catheter ablation (CA) and left atrial appendage closure (LAAC) require transseptal access; combining both in a single procedure may have advantages. However, the safety of this approach has not been extensively studied. The objective of this study was to compare in hospital outcomes among patients receiving CA, LAAC, and combination of both treatments on the same day.

METHODS

We conducted a retrospective cohort analysis of the National Inpatient Sample database. The primary outcome was the presence of major adverse cardiovascular and cerebrovascular events (MACCE) during index hospitalization. Secondary outcomes included stroke, pericardial effusion, pericardiocentesis, and bleeding.

RESULTS

A total of 69,285 hospitalizations with AF were included in the analysis, of which 71.7% received LAAC, 27.8% received CA, and 0.5% received combination of both treatments on the same day. MACEE (OR, 1.63; 95% CI, 0.39-6.70), stroke (OR, 2.98; 95% CI, 0.55-16.01), pericardial effusion (OR, 0.33; 95% CI, 0.07-1.41), pericardiocentesis (OR, 1.00; 95% CI, 0.25-3.86), and bleeding (OR, 3.25; 95% CI, 0.87-12.07) did not differ significantly between CA and combination treatment. Similarly, MACCE (OR, 1.11; 95% CI, 0.28-4.41), stroke (OR, 1.03; 95% CI, 0.24-4.35), pericardial effusion (OR, 0.45; 95% CI, 0.11-1.90), pericardiocentesis (OR, 0.63; 95% CI, 0.14-2.83), and bleeding (OR, 2.04; 95% CI, 0.65-6.39) did not differ significantly between LAAC and combination treatment.

CONCLUSIONS

The combined approach is infrequently used in clinical practice (< 1%). However, major life-threatening adverse events did not differ between CA and LAAC when performed in isolation or combined in a single procedural stage on the same day.

Higher serum sST2 is associated with increased left atrial low-voltage areas and atrial fibrillation recurrence in patients undergoing radiofrequency ablation

OBJECTIVE

To conduct a comprehensive analysis of prospectively measuring the concentration of soluble suppression of tumorigenicity 2 (sST2) to predict left atrial (LA) low-voltage areas (LVAs) and atrial fibrillation (AF) recurrence after radiofrequency catheter ablation (RFA).

METHODS

This was a prospective cohort study. A total of 84 patients, including 54 paroxysmal AF cases and 30 persistent AF cases who underwent RFA, were recruited. Electroanatomical voltage mapping determined the extent of LVAs. The serum level of sST2 was measured by enzyme-linked immunosorbent assay. All patients were followed for 12 months after the RFA procedure to verify AF recurrence.

RESULTS

The concentration of sST2 measured in the sample was 17.90-198.77 pg/mL, and the range of LA LVAs was 0-85.6%. The sST2 level positively correlated with LVAs (r = 0.40; P = 0.005). When comparing the top and bottom quartile, sST2 is significantly associated with LA LVAs (OR = 1.833, 95% CI: 1.582-2.011, P = 0.004). When compared with the 1st quartile group, the multivariable adjusted hazard ratios for AF recurrence after RFA were 1.57 (95% CI: 1.182-1.795) for the 4th quartile group, 1.44 (95% CI: 1.085-1.598) for the 3rd quartile group, and 1.27 (95% CI: 0.954-1.318) for the 2nd quartile group. The AF-free survival rates of patients with 1st quartile and 4th quartile sST2 levels after ablation were 95% and 59.6%, respectively (Log Rank test, P = 0.027).

CONCLUSION

Elevated sST2 levels of AF patients were associated with higher LA LVAs and a significantly increased risk of recurrence. The circulating sST2 concentration might be a pre-diagnostic marker of AF recurrence after RFA.

Evaluation of linear lesion formation and thermodynamics by dragging ablation with the third-generation laser balloon

Background

The lesion formation properties of a motorized rotational delivery (RAPID) mode, third-generation laser balloon (LB3) ablation compared to point-by-point laser ablation in patients with atrial fibrillation remain unclear.

Objective

The purpose of this study was to assess lesion characteristics and thermodynamics in LB3 ablation with a RAPID mode in vitro model.

Methods

Chicken muscles were cauterized using LB3 in RAPID mode with 13 W and 15 W and 50% overlapped point-by-point fashion with 7 W/30 seconds, 8.5 W/20 seconds, 10 W/20 seconds, and 12 W/20 seconds. Lesion depth, width, and continuity were compared. Lesion continuity was classified by the visible gap degree categorized from 1 (perfect) to 3 (poor). Thermodynamics and maximum tissue temperatures were assessed under infrared thermographic monitoring. Fifteen and 5 lesions were evaluated per ablation protocol for measurement of lesion size and continuity and for thermographic assessment, respectively.

Results

Lesion depth and width were smaller in RAPID mode laser ablation than point-by-point laser ablation (P <.001). However, RAPID mode laser ablation revealed sufficient mean lesion depth of 5 mm or more. Lesion continuity was 1 (perfect) in all samples in RAPID mode laser ablation and point-by-point laser ablation (P = 1). Infrared thermographic observation demonstrated fast and gapless linear lesion formation with thermal stacking in RAPID mode laser ablation. Maximum tissue temperature was lower in RAPID mode laser ablation than point-by-point laser ablation (P <.001).

Conclusion

RAPID mode LB3 ablation could provide fast, gapless, and acceptable lesion formation with thermal stacking and moderate tissue temperature rise.

Long term comparisons of atrial fibrillation ablation outcomes with a cryo-balloon or laser-balloon: a propensity-matched analysis based on continuous rhythm monitoring

BACKGROUND

Cryoballoon (CB) and laser-balloon (LB) catheter ablation (CA) have been demonstrated to achieve durable and effective pulmonary vein isolation (PVI). Only one head-to-head comparison with an intermittent rhythm monitor strategy is currently available. Aim of this study was to compare acute and long-term outcomes of CB and LB atrial fibrillation ablation procedures, using a continuous rhythm monitoring strategy.

METHODS

This was a prospective two-arm non-randomized propensity-matched observational trial, comparing the outcomes of atrial fibrillation (AF) ablation using LB and CB techniques. To evaluate AF recurrences, an implantable cardiac monitor (ICM) was implanted prior to hospital discharge to detect atrial tachyarrhythmias (ATAs) recurrences.

RESULTS

110 propensity-matched patients undergoing AF ablation with a LB (n=55) or with a CB system (n=55) were enrolled (paroxysmal AF 57.3%). Procedural time (LB: 87 [73-104] vs CB 90 [70-130] min; p=0.264) and fluoroscopy time did not differ. No differences in ATAs recurrences were observed at 12-month (LB-30.9% vs CB-29.1% and LB-45.5% vs CB-38.2%; log-rank 0.539). As for AF burden, the 12-month median was 0 [0-1] vs 0 [0-3]% (p=0.127), in the LB and CB-group, respectively. When considering only PeAF patients, median 12-month ATAs burden was 26 [18.5-40.5] vs 29 [26-35] % for the LB and CB patients (p=0.919).

CONCLUSION

In a propensity-matched cohort undergoing AF ablation, arrhythmia outcomes assessed by continuous rhythm monitoring did not differ between LB and CB, with an overall low ATAs burden. The only predictor of recurrences was persistent AF. There was no difference in procedure or fluoroscopy time.

Recent advances in the tools available for atrial fibrillation ablation

INTRODUCTION

Atrial fibrillation (AF) is the commonest arrhythmia in clinical practice with significant detrimental health impacts. Much effort has been spent in mapping AF, determine its triggers and drivers, and how to develop tools to eliminate these triggers.

AREAS COVERED

In this state of-the-art review article, we aim to highlight the recent techniques in catheter-based management of Atrial Fibrillation; including new advancements either in the catheter design or the software used. This includes a comprehensive summary of the most recent tools used in AF mapping and subsequent ablation.

EXPERT OPINION

Electrical isolation of the pulmonary veins has been developed and established as the cornerstone in AF ablation with good results in patients with paroxysmal AF (PAF) whilst new ablation tools are aimed at streamlining the procedure. However, the quest for persistent AF (PeAF) remains. The future of AF ablation, we believe, lies in identifying AF drivers by means of the new developing mapping tools and altering their electrical properties in a safe, reproducible, and effective manner.

Factors affecting signal quality in implantable cardiac monitors with long sensing vector

PURPOSE

Electrical artefacts are frequent in implantable cardiac monitors (ICMs). We analyzed the subcutaneous electrogram (sECG) provided by an ICM with a long sensing vector and factors potentially affecting its quality.

METHODS

Consecutive ICM recipients underwent a follow-up where demographics, body mass index (BMI), implant location, and surface ECG were collected. The sECG was then analyzed in terms of R-wave amplitude and P-wave visibility.

RESULTS

A total of 84 patients (43% female, median age 68 [58-76] years) were enrolled at 3 sites. ICMs were positioned with intermediate inclination (n = 44, 52%), parallel (n = 35, 43%), or perpendicular (n = 5, 6%) to the sternum. The median R-wave amplitude was 1.10 (0.72-1.48) mV with P waves readily visible in 69.2% (95% confidence interval, CI: 57.8%-79.2%), partially visible in 23.1% [95% CI: 14.3%-34.0%], and never visible in 7.7% [95% CI: 2.9%-16.0%] of patients. Men had higher R-wave amplitudes compared to women (1.40 [0.96-1.80] mV vs 1.00 [0.60-1.20] mV, P = .001), while obese people tended to have lower values (0.80 [0.62-1.28] mV vs 1.10 [0.90-1.50] mV, P = .074). The P-wave visibility reached 86.2% [95% CI: 68.3%-96.1%] in patients with high-voltage P waves (≥0.2 mV) at surface ECG. The sECG quality was not affected by implant site.

CONCLUSION

In ordinary clinical practice, ICMs with long sensing vector provided median R-wave amplitude above 1 mV and reliable P-wave visibility of nearly 70%, regardless of the position of the device. Women and obese patients showed lower but still very good signal quality.

Validation of lesion durability following pulmonary vein isolation using the new third-generation laser balloon catheter in patients with recurrent atrial fibrillation

BACKGROUND

The second- and third-generation endoscopic ablation systems (EAS2 and EAS3) have been launched in recent years. We aimed to assess the lesion durability as well as gap localization using the multigenerational novel technologies in patients with recurrent atrial fibrillation (AF).

METHODS

Consecutive patients who underwent second ablation for recurrent AF following the initial pulmonary vein isolation (PVI) with EAS2 or EAS3 were retrospectively investigated. The persistent durability of PVI, gap localization at the second procedure, and procedural/anatomical features of durable PVI were analyzed.

RESULTS

Among 225 patients treated with EAS3 (N = 125) and EAS2 (N = 100), 34 patients (EAS3: 13 patients, 50 PVs, EAS2: 21 patients, 82 PVs) underwent a second procedure because of recurrent AF mean 11.9 ± 9.3 months after the initial procedure. Persistent isolation of all four PVs was recorded in 6 (46.2%) patients in EAS3 group and 4 (19.1%) patients in EAS2 group (p = 0.130). Ninety-one out of 132 (68.9%) PVs were persistently isolated with a higher rate in EAS3 group (82.0% vs. EAS2 group: 61.0%, p = 0.0113). A total of 45 gaps were recorded in 41 PVs. Right superior PV (RSPV) was the predominantly common reconnected vein (15 gaps, 14 PVs) irrespective of generations (EAS3: 4 gaps in 3 PVs and EAS2: 12 gaps in 11 PVs). Logistic multivariate regression analysis revealed ablation without reduced energy dose (5.5-7 W) as an independent predictor of durable PVI [adjusted OR: 3.70, 95% CI (1.408-10.003)], p = 0.008].

CONCLUSION

The technical innovation resulted in a higher lesion durability in EAS3-guided PVI in patients with recurrent AF. The most common gap location was found at RSPV in successor EASs. Ablation without reduced energy was a predictor of durable PVI in successor EASs.