Progress in atrial fibrillation ablation during 25 years of Europace journal

Procedural and Clinical Outcomes of High-Frequency Low-Tidal Volume Ventilation Plus Rapid-Atrial Pacing in Paroxysmal Atrial Fibrillation Ablation

BACKGROUND

High-frequency low-tidal-volume (HFLTV) ventilation is a safe and cost-effective strategy that improves catheter stability, first-pass pulmonary vein isolation, and freedom from all-atrial arrhythmias during radiofrequency catheter ablation (RFCA) of paroxysmal and persistent atrial fibrillation (AF). However, the incremental value of adding rapid-atrial pacing (RAP) to HFLTV-ventilation has not yet been determined.

OBJECTIVE

To evaluate the effect of HFLTV-ventilation plus RAP during RFCA of paroxysmal AF on procedural and long-term clinical outcomes compared to HFLTV-ventilation alone.

METHODS

Patients from the REAL-AF prospective multicenter registry, who underwent RFCA of paroxysmal AF using either HFLTV + RAP (500-600 msec) or HFLTV ventilation alone from April 2020 to February 2023 were included. The primary outcome was freedom from all-atrial arrhythmias at 12-month follow-up. Secondary outcomes included procedural characteristics, long-term clinical outcomes, and procedure-related complications.

RESULTS

A total of 545 patients were included in the analysis (HFLTV + RAP = 327 vs. HFLTV = 218). There were no significant differences in baseline characteristics between the groups. No differences were observed in procedural (HFLTV + RAP 74 [57-98] vs. HFLTV 66 [53-85.75] min, p = 0.617) and RF (HFLTV + RAP 15.15 [11.22-21.22] vs. HFLTV 13.99 [11.04-17.13] min, p = 0.620) times. Both groups showed a similar freedom from all-atrial arrhythmias at 12-month follow-up (HFLTV + RAP 82.68% vs. HFLTV 86.52%, HR = 1.43, 95% CI [0.94-2.16], p = 0.093). There were no significant differences in freedom from AF-related symptoms (HFLTV + RAP 91.4% vs. HFLTV 93.1%, p = 0.476) or AF-related hospitalizations (HFLTV + RAP 98.5% vs. HFLTV 97.2%, p = 0.320). Procedure-related complications were low in both groups (HFLTV + RAP 0.6% vs. HFLTV 0%, p = 0.247).

CONCLUSION

In patients undergoing RFCA for paroxysmal AF, adding RAP to HFLTV-ventilation was not associated with improved procedural and long-term clinical outcomes.

Ablation characteristics associated with steam pops in ablation index-guided radiofrequency ablation of atrial fibrillation

AIMS

Steam pops present a significant concern during radiofrequency (RF) ablation of atrial fibrillation (AF). It is crucial to analyse the incidence and ablation characteristics associated with steam pops. This study aims to investigate the occurrence and potential predictors of steam pops.

METHODS AND RESULTS

This study included 3263 patients with AF who underwent RF ablation. Patients with paroxysmal AF received bilateral circumferential pulmonary vein (PV) ablation, while those with persistent AF underwent additional linear ablation. The ablation parameters at the sites of steam pops were compared to those at adjacent anatomical locations. A total of 81 steam pops (2.5%) with one pericardial tamponade were recorded. Steam pops were observed at liner ablation sites: 6 (0.4%) at the mitral isthmus, 16 (0.9%) at the tricuspid isthmus (CTI), and 7 (0.5%) along the roofline. The most common sites of steam pops were the anterior edge of the left superior PV and the inferior vena cava side of the CTI. The impedance drop was significantly higher (18.2 ± 9.5 Ω vs. 13.5 ± 4.8 Ω, P < 0.001) at steam pop sites. The optimal cut-off points of impedance drop for predicting steam pops were > 9.5 Ω within the first 3 s, > 10.5 Ω within the first 5 s, > 13.5 Ω within the first 10 s, and > 18.5 Ω in the whole ablation, respectively.

CONCLUSION

The incidence of steam pops during ablation of AF is infrequent. Impedance drop is the only ablation parameter that could predict the occurrence of steam pops.

Identifying extra pulmonary vein targets for persistent atrial fibrillation ablation: bridging advanced and conventional mapping techniques

AIMS

Advanced technologies such as charge density mapping (CDM) show promise in guiding adjuvant ablation in patients with persistent atrial fibrillation (AF); however, their limited availability restricts widespread adoption. We sought to determine whether regions of the left atrium containing CDM-identified pivoting and rotational propagation patterns during AF could also be reliably identified using more conventional contact mapping techniques.

METHODS AND RESULTS

Twenty-two patients undergoing de novo ablation of persistent AF underwent both CDM and electroanatomic voltage mapping during AF and sinus rhythm with multiple pacing protocols. Through the use of a left atrium statistical shape model, the location of distinctive propagation patterns identified by CDM was compared with low-voltage areas (LVAs) and regions of slow conduction velocity (CV). Neither LVA nor CV mapping during paced rhythms reliably identified regions containing CDM propagation patterns. Conduction velocity mapping during AF did correlate with these regions (ρ = -0.63, P < 0.0001 for pivoting patterns; ρ = -0.54, P < 0.0001 for rotational patterns). These propagation patterns consistently occurred in two specific anatomical regions across patients: the anteroseptal and inferoposterior walls of the left atrium.

CONCLUSION

Mapping techniques during paced rhythms do not reliably correspond with regions of CDM-identified propagation patterns in persistent AF. However, these propagation patterns are consistently observed in two specific anatomical regions, suggesting a predisposition to abnormal electrophysiological properties. While further research is needed, these regions may serve as promising targets for empirical ablation, potentially reducing the reliance on complex mapping techniques.

Aggressive ablation vs. regular ablation for persistent atrial fibrillation: a multicentre real-world cohort study

AIMS

Current guidelines for the optimal ablation strategy for persistent atrial fibrillation (PerAF) remain unclear. While our previous RCT confirmed the favourable prognosis of aggressive ablation, real-world evidence is still lacking.

METHODS AND RESULTS

Among 4833 PerAF patients undergoing catheter ablation at 10 centres, two groups were defined: regular ablation (PVI-only or PVI plus anatomical ablation) and aggressive ablation (anatomical plus electrogram-guided ablation), with 1560 patients each after propensity score (PS) matching. The primary endpoint was 12-month AF/atrial tachycardia (AT) recurrence-free survival off anti-arrhythmic drugs after a single procedure. Additional PS matching was performed within the regular group between PVI-only and anatomical ablation (n = 455 each). Furthermore, anatomical ablation from the regular group was independently matched with aggressive ablation (n = 1362 each). At 12 months, the aggressive group showed superior AF/AT-free survival (66.2% vs. 59.3%, P < 0.001; HR 0.745), similar AT recurrence (12.0% vs. 11.3%, P = 0.539), and significantly higher procedural AF termination (67.0% vs. 21.0%, P < 0.001) than regular group. Moreover, patients with AF termination had improved AF/AT-free survival (72.3% vs. 55.2%, P < 0.001). Safety endpoints did not differ significantly between the two groups. Both the ablation outcomes and AF termination rate showed increasing trends with the extent of ablation aggressiveness but declined with extremely aggressive ablation. After additional PS matching, within the regular group, no statistical differences were observed though AF/AT-free survival in the anatomical group was slightly higher than the PVI-only group (60.7% vs. 55.6%, P = 0.122); while aggressive ablation showed improved AF/AT-free survival compared to anatomical ablation alone from regular group (67.5% vs. 59.9%, P < 0.001).

CONCLUSION

Aggressive ablation achieved more favourable outcomes than regular ablation, and moderately aggressive ablation may be associated with better clinical outcomes. AF termination is a reliable ablation endpoint.

Thermal side effects during pulsed field ablation: an analysis using computer modelling

AIMS

Pulsed field ablation (PFA) is described as non-thermal, but data from oncology and cardiology show thermal effects occur. The specific waveform parameters influencing thermal energy development during PFA are unclear. The aim of this study is to numerically evaluate the thermal effects of PFA on myocardial and oesophageal tissue at various peak voltage conditions.

METHODS AND RESULTS

A three-dimensional computer model of the left atrium quantified thermal effects from PFA at peak voltages of 1, 1.5, and 2 kV. Energy was applied using a bipolar configuration with far-field and symmetry boundaries set as electrically insulating. A monophasic waveform with a 100 μs pulse width and a 1 s gap between pulses was applied for a total of 50 pulses, mimicking clinical conditions. Minimal temperature rise in the oesophagus was observed with 1 kV pulses (214.5 J). At 1.5 and 2 kV (570.3 and 1.23 kJ), temperatures reached 46.3°C and >62°C, respectively, after a single pulse train. These findings suggest that repeated applications could lead to even higher temperatures, especially if good tissue contact is obtained. These results align with data from other medical fields using pulsed field treatments.

CONCLUSION

Thermal effects from PFA depend on the total energy deposited, with peak voltage being a significant factor. Current commercially available PFA systems have the potential to induce collateral thermal injury with repeated applications of pulsed field energy. This highlights the need for careful monitoring and adjustment of PFA parameters in clinical settings.

First-in-human trial of atrial fibrillation ablation using real-time tissue optical assessment to predict pulsed field lesion durability

AIMS

Loss of bipolar electrograms immediately after pulsed field ablation (PFA) makes lesion durability assessment challenging.

OBJECTIVE

The aim of this trial (NCT06700226) was to evaluate a novel ablation system that can optically predict lesion durability by detecting structural changes in the tissue during ablation.

METHODS AND RESULTS

Patients with paroxysmal atrial fibrillation underwent pulmonary vein isolation (PVI) using PFA (AblaView®, MedLumics). Using polarization-sensitive optical coherence reflectometry (PS-OCR), reflective characteristics of myocardial tissue and visualization of real-time contrast between healthy tissue and ablated tissue using a drop in tissue birefringence (BiR) was assessed. Wide antral PVI was performed using single point irrigated PFA (unipolar, 1800V, 3 trains, 21 s). Remapping was performed at 3 months. Primary efficacy outcome was the ability of PS-OCR to predict lesion durability at 3-month remapping. Serious adverse events were recorded. Ten patients were included. In total, 38/40 PVs could be isolated with the system. The mean drop of BiR was 17.3 ± 11.5%. Dragging across the ablation lines showed a persistent drop in BiR. During the remap procedures (8/10 patients ablated only with PFA), 12 PVs (37.5%) were found to be electrically reconnected. The mean loss of BiR during all PFA for durable lesions was 20.9%, while only 10.1% BiR loss was observed during the index ablation for reconnected areas (P < 0.001). None of the points with ≥17% loss of birefringence was found to be reconnected.

CONCLUSION

This first-in-human study supports the use of real-time drop in tissue BiR for lesion assessment and durability during PFA delivery, and its procedural safety.

Comparative analysis of anaesthesia modalities in pulmonary vein isolation: insights from a prospective multicentre registry

AIMS

Atrial fibrillation (AF), the most common sustained arrhythmia in adults, is increasing in prevalence globally. Catheter ablation (CA), particularly pulmonary vein isolation (PVI), is a key treatment option. Pulmonary vein isolation can be performed using different energy sources, including cryoballoon ablation (CBA), radiofrequency ablation (RFA), or pulse field ablation. Anaesthesia modalities for these procedures include general anaesthesia (GA), deep sedation (DS), and conscious sedation (CS). However, the optimal anaesthesia modality remains unclear, as previous studies have shown mixed outcomes. This study aims to compare the safety and efficacy of different anaesthesia modalities in PVI.

METHODS AND RESULTS

This prospective, multicentre study, based on the Israeli Catheter Ablation Registry, evaluated the impact of different anaesthesia modalities on procedural outcomes and safety in AF ablation. Data from 1002 patients who underwent PVI between January 2019 and December 2021 across 14 centres were analysed. Patients were stratified by anaesthesia modality-CS vs. GA, with the latter encompassing DS. Key outcomes, including AF recurrence, procedural complications, and success rates, were evaluated over a 24-month follow-up period. Additionally, a sensitivity analysis was performed for the subgroup of patients who underwent CBA. Of the 1002 patients, 53% received GA, 6.3% DS, and 40% CS, with CBA used in 84% of cases. Complete PVI was achieved in 91% of patients, with comparable success rates observed between CS and GA groups. No significant differences were found between CS and GA modalities in terms of AF recurrence rates at 12 months (15% vs. 16%) and 24 months (19.5% vs. 21.2%), or in 12-month rehospitalization rates (19.8% vs. 16.5%). Sensitivity analysis of the CBA subgroup yielded similar results, with no significant differences in AF recurrence, complications, or procedural duration between CS and GA modalities.

CONCLUSION

Conscious sedation is as safe and effective as general anaesthesia in AF ablation, particularly with cryoablation. The choice of anaesthesia appears to be driven by patient characteristics and institutional factors without affecting long-term outcomes such as AF recurrence or complication rates.

Impact of atrial fibrillation diagnosis-to-ablation time on 24-month efficacy and safety outcomes in the Cryo Global Registry

AIMS

Early rhythm control therapy in atrial fibrillation (AF) results in higher freedom from atrial arrhythmia (AA) recurrence and improved cardiovascular outcomes. The optimal timing of cryoballoon ablation (CBA) is unknown.

METHODS AND RESULTS

We evaluated AA recurrence and procedure-related complications of early vs. late CBA (≤12 vs. >12 months from diagnosis) in patients enrolled in the prospective Cryo Global Registry (121 centres in 37 countries, NCT02752737). A total of 3447 subjects were followed through 12 months and 1220 through 24 months. In summary, 1573 patients (46%) had early ablation at a median (IQR) of 0.3 (0.1-0.6) years from AF diagnosis (age 62 ± 12 years., 35.8% female, 71.4% paroxysmal), and 1874 (54%) had late ablation at a median of 3.4 (1.9-6.7) years after diagnosis (age 61 ± 11 years, 36.2% female, 75.0% paroxysmal). Early ablation patients were less hypertensive (53.5% vs. 57.9%, P = 0.01) and less symptomatic (1.5 ± 1.1 vs. 1.8 ± 1.1 symptoms/patient, P < 0.01) and had smaller left atrial diameters (41 ± 7 mm vs. 42 ± 7 mm, P < 0.01). Freedom from AA recurrence was 81.5% (95% CI: 78.7-83.9%) in the early vs. 71.7% (95% CI: 68.9-74.3%) in the late ablation group at 24 months (P < 0.01). The risk of cardioversion was 41% lower in the early ablation group [HRAdj: 0.59 (0.42-0.83), P < 0.01]. Serious procedure-related adverse events occurred in 2.4 and 3.5% of patients in the early and late ablation groups (P = 0.045), respectively.

CONCLUSION

CBA within 12 months from AF diagnosis resulted in higher freedom from AA recurrence and is associated with fewer safety events in a real-world evaluation.

CLINICAL TRIAL REGISTRATION

https://clinicaltrials.gov/ct2/show/NCT02752737.

Early versus late atrial fibrillation recurrence after pulsed field ablation: insights from the admIRE trial

AIMS

Studies have shown correlations between early recurrence (ER) and late recurrence (LR) of atrial arrhythmia after ablation with thermal technologies. This admIRE trial (NCT05293639) subanalysis aims to analyse ER vs. LR in patients with paroxysmal atrial fibrillation (PAF) undergoing pulsed field ablation (PFA).

METHODS AND RESULTS

Patients with symptomatic paroxysmal atrial fibrillation and ≥1 transtelephonic monitoring transmission during the blanking period were included (n = 169). ER was defined as documented recurrence in the blanking period (days 1-90), and LR as recurrence in the evaluation period (days 91-365). Freedom from 12-month recurrence was estimated using Kaplan-Meier method. A Cox proportional-hazards regression model, with ER as the primary factor, and adjusted for age, sex, and body mass index, was used to estimate hazard ratios (HRs) and 95% CI. ER was observed in 20.1% (31/169) of patients (66.1 ± 7.1 years, 35.5% female, 46.6 ± 48.4-month PAF history). Time to first documented ER was 49 (37-61) days. Occurrence of LR was 16.7% (23/138) in patients without ER, 71.0% (22/31) in those with ER, and 87.0% (20/23) in patients whose ER onset occurred within the first 2 months. Twelve-month freedom from documented recurrence was significantly lower in patients with ER at 29.0% (95% CI, 13.1-45.0%) vs. 82.5% (95% CI, 75.9-89.1%) in those without ER (adjusted HR, 7.9; 95% CI, 4.1-15.1; P < 0.001).

CONCLUSION

This admIRE subanalysis demonstrated that PAF patients who experience ER after PFA are at a substantially higher risk for LR. The optimal duration of the blanking period post-PFA needs further assessments.

CLINICALTRIALS.GOV IDENTIFIER

NCT05293639.

Using computed tomography atrial myocardial thickness maps in cryoballoon pulmonary vein isolation: the UTMOST AF II randomized clinical trial

AIMS

Whether adjusting the duration of ablation based on left atrial wall thickness (LAWT) provides extra benefits for pulmonary vein (PV) isolation for atrial fibrillation (AF) is uncertain. We studied the safety and efficacy of tailored cryoballoon PV isolation (CB-PVI) based on LAWT for paroxysmal AF.

METHODS AND RESULTS

Two hundred seventy-seven patients with paroxysmal AF refractory to anti-arrhythmic drug were randomized 1:1 to either LAWT-guided CB-PVI (n = 135) and empirical CB-PVI (n = 142). Empirical CB-PVI was performed using a 28 mm cryoballoon with recommended application for 240 s per ablation. Cryoapplication in the LAWT-guided group was titrated (additional application for 120 s at PVs, where >25% of the circumference includes segments with LAWT > 2.5 mm and reduced baseline application to 180 s at PVs where >75% of the circumference includes segments with LAWT < 1.5 mm) according to the computed tomography LAWT colour map. The primary endpoint was freedom from any documented atrial arrhythmia of more than 30 s without antiarrhythmic medication, after a single ablation procedure. During a mean follow-up of 18.7 months, patients in the LAWT-guided CB-PVI group (70.8%) had a higher event-free rate from primary endpoint than those in the empirical CB-PVI group (54.4%; hazard ratio 0.64, 95% confidence interval 0.42-0.99; P = 0.043). No differences were observed between the groups in complication rates (3.0% in LAWT-guided vs. 4.9% in empirical CB-PVI). The total procedure time was extended in the LAWT group than in the empirical group (mean 70.2 vs. 65.2 min, respectively).

CONCLUSION

The LAWT-guided energy titration strategy improved freedom from atrial arrhythmia recurrence, compared with conventional strategy.

Spotlight on the 2024 ESC/EACTS management of atrial fibrillation guidelines: 10 novel key aspects

Atrial fibrillation (AF) remains the most common cardiac arrhythmia worldwide and is associated with significant morbidity and mortality. The European Society of Cardiology (ESC)/European Association for Cardio-Thoracic Surgery (EACTS) have recently released the 2024 guidelines for the management of AF. This review highlights 10 novel aspects of the ESC/EACTS 2024 Guidelines. The AF-CARE framework is introduced, a structural approach that aims to improve patient care and outcomes, comprising of four pillars: [C] Comorbidity and risk factor management, [A] Avoid stroke and thromboembolism, [R] Reduce symptoms by rate and rhythm control, and [E] Evaluation and dynamic reassessment. Additionally, graphical patient pathways are provided to enhance clinical application. A significant shift is the new emphasis on comorbidity and risk factor control to reduce AF recurrence and progression. Individualized assessment of risk is suggested to guide the initiation of oral anticoagulation to prevent thromboembolism. New guidance is provided for anticoagulation in patients with trigger-induced and device-detected sub-clinical AF, ischaemic stroke despite anticoagulation, and the indications for percutaneous/surgical left atrial appendage exclusion. AF ablation is a first-line rhythm control option for suitable patients with paroxysmal AF, and in specific patients, rhythm control can improve prognosis. The AF duration threshold for early cardioversion was reduced from 48 to 24 h, and a wait-and-see approach for spontaneous conversion is advised to promote patient safety. Lastly, strong emphasis is given to optimize the implementation of AF guidelines in daily practice using a patient-centred, multidisciplinary and shared-care approach, with the simultaneous launch of a patient version of the guideline.

Multielectrode catheter-based pulsed electric field vs. cryoballoon for atrial fibrillation ablation: a systematic review and meta-analysis

AIMS

Pulsed field ablation (PFA) is an innovative technology recently adopted for the treatment of atrial fibrillation (AF). Preclinical and clinical studies have reported a remarkable safety profile, as a result of its tissue-specific effect targeting cardiomyocytes and sparing adjacent tissues. Single-shot pentaspline system was the first PFA device to receive regulatory approval. We performed a meta-analysis to compare the efficacy and safety of PFA with the single-shot pentaspline system vs. currently available second-/third-/fourth-generation cryoballoon ablation (CRYO) technologies.

METHODS AND RESULTS

We systematically searched electronic databases for studies focusing on AF ablation employing the PFA single-shot pentaspline system or second-/third-/fourth-generation CRYO technologies. The primary endpoints were acute procedural success assessed on a vein and patient basis. Safety endpoints included overall periprocedural complications and major periprocedural complications. We also compared procedural, fluoroscopy times, and freedom from atrial tachyarrhythmias (ATs) at follow-up (secondary endpoints). Twenty and 70 studies were included for PFA and CRYO, respectively. Pulsed field ablation demonstrated greater acute procedural success on a vein basis (99.9% vs. 99.1%; P < 0.001), as well as per patient (99.5% vs. 98.4%; P < 0.001). Pulsed field ablation yielded lower overall periprocedural complications (3.1% vs. 5.6%; P < 0.001), shorter procedural time (75.9 min vs. 105.6 min; P < 0.001), and fluoroscopy time (14.2 min vs. 18.9 min; P < 0.001) compared with CRYO. No differences were found for major periprocedural complications (1.2% vs. 1.0%; P = 0.46) and freedom from ATs at 1 year (82.3% vs. 80.3%; log-rank P = 0.61).

CONCLUSION

Pulsed field ablation contributed to higher acute procedural success and safety compared with CRYO. No statistically significant differences in AT recurrence at 1-year follow-up were observed.

Early rhythm control in atrial fibrillation anno 2024

Atrial fibrillation is a chronic progressive disease and is the most common arrhythmia in adults. It is a major cause of cardiovascular morbidity and mortality. The EAST-AFNET 4 trial demonstrated that rhythm control in patients with early atrial fibrillation significantly reduces cardiovascular outcomes compared to usual care. The effectiveness of early rhythm control is predominantly mediated by the presence of sinus rhythm and early rhythm control is more effective in patients with multiple comorbidities. Studies such as STOP-AF First, Cryo-FIRST, EARLY-AF and its 3-year follow-up trial demonstrate that first-line catheter ablation is more effective in maintaining sinus rhythm than anti-arrhythmic drug therapy. These findings are leading to a paradigm shift in the electrophysiology community in favour of early rhythm control with catheter ablation when feasible.

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

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

2024 updated European Heart Rhythm Association core curriculum for physicians and allied professionals: a statement of the European Heart Rhythm Association of the European Society of Cardiology

Heart rhythm management is a continuously evolving sub-speciality of cardiology. Every year, many physicians and allied professionals (APs) start and complete their training in cardiac implantable electronic devices (CIEDs) or electrophysiology (EP) across the European Heart Rhythm Association (EHRA) member countries. While this training ideally ends with an EHRA certification, the description of the learning pathway (what, how, when, and where) through an EHRA core curriculum is also a prerequisite for a successful training. The first EHRA core curriculum for physicians was published in 2009. Due to the huge developments in the field of EP and device therapy, this document needed updating. In addition, a certification process for APs has been introduced, as well as a recertification process and accreditation of EHRA recognized training centres. Learning pathways are more individualized now, with Objective Structured Assessment of Technical Skills (OSATS) to monitor learning progression of trainees. The 2024 updated EHRA core curriculum for physicians and APs describes, for both CIED and EP, the syllabus, OSATS, training programme and certification, and recertification for physicians and APs and stresses the importance of continued medical education after certification. In addition, requirements for accreditation of training centres and trainers are given. Finally, suggested reading lists for CIED and EP are attached as online supplements.

Impact of dispersive patch electrode positioning on safety and efficacy of radiofrequency catheter ablation

Safe and efficient radiofrequency catheter ablation depends significantly on the proper placement of dispersive patch electrodes (DPEs), on the skin. This viewpoint describes the role of DPE positioning in optimizing lesion creation and reducing the risk of complications. Incorrect DPE placement can lead to suboptimal energy delivery, prolonging the procedure and/or increasing the risk of adverse events, such as steam pops and potentially fatal atrio-oesophageal fistula. Despite its importance, there is no consensus on the optimal positioning of DPE, and current studies require further improvement in predictive modelling.

Anatomical-guided third-generation laser balloon ablation for the treatment of paroxysmal atrial fibrillation assessed by continuous rhythm monitoring: results from a multicentre prospective study

AIMS

The third-generation laser balloon (LB3) is an established ablation device for pulmonary vein isolation (PVI) that allows direct visualization of the anatomical target. Equipped with an automatic circumferential laser delivery modality, it aims at continuous circumferential PVI, improving both acute and clinical outcomes. We sought to evaluate the clinical efficacy of LB3 ablation using an anatomical-based approach without verifying electrical isolation.

METHODS AND RESULTS

Among 257 paroxysmal AF patients undergoing LB3 ablation across four Italian centres, 204 (72% male, mean age 60.4 ± 11.1 years) were included. The primary endpoint was freedom from any atrial tachyarrhythmia (ATa) recurrence after the blanking period (BP), assessed with implantable cardiac monitors (ICMs). All pulmonary veins (PVs) were targeted using the LB3, with the RAPID mode used on an average of 96 ± 8, 86 ± 19, 98 ± 11, and 84 ± 15% for the left superior, left inferior, right superior, right inferior PV, and left common ostium, respectively. Freedom from arrhythmia recurrences was 84.8% at 1, 80.4% at 2, and 76.0% at 3 years. An ATa burden ≥ 5% was documented in 2.5, 4.4, and 5.4% at 1, 2, and 3 years, respectively. Relapses during the BP [hazard ratio (HR) = 2.182, P = 0.032] and left atrial dilation (HR = 1.964, P = 0.048) were independent predictors of recurrences.

CONCLUSION

Anatomical-guided LB3 ablation for paroxysmal AF is a safe and effective approach, providing excellent clinical outcomes as assessed by ICM over nearly 3 years of follow-up.

Are drivers recurring or ephemeral? observations from serial mapping of persistent atrial fibrillation

AIMS

Rotational re-entries and ectopic foci, or 'drivers', are proposed mechanisms for persistent atrial fibrillation (persAF), but driver-based interventions have had mixed success in clinical trials. Selective targeting of drivers with multi-month stability may improve these interventions, but no prior work has investigated whether drivers can be stable on such a long timescale.

OBJECTIVE

We hypothesized that drivers could recur even several months after initial observation.

METHODS AND RESULTS

We performed serial electrophysiology studies on paced canines (n = 18, 27-35 kg) at 1-, 3-, and 6 months post-initiation of continual persAF. Using a high-density 64-electrode catheter, we captured endocardial electrograms in the left atrium (LA) and right atrium (RA) to determine the presence of drivers at each major anatomical site. We defined drivers that were repeatedly observed across consecutive studies to be recurrent. The mean probability that any driver would recur was 66% (LA: 73%, RA: 41%). We also found evidence of 'multi-recurring' drivers, i.e. those seen in all three studies. Multi-recurring drivers constituted 53% of initially observed drivers with at least one found in 92% of animals, and we found more multi-recurring drivers per animal than predicted by random chance (2.6 ± 1.5 vs. 1.2 ± 1.1, P < 0.001). Driver sites showed more enhancement than non-drivers during late gadolinium enhancement-magnetic resonance imaging (P = 0.04), but we observed no relationship between enhancement and driver recurrence type.

CONCLUSION

We observed recurring drivers over a 6-month period at fixed locations, confirming our hypothesis. We also found drivers to be associated with fibrosis, implying a structural basis.

Early rapid local impedance drop is associated with acute lesion efficacy during pulmonary vein isolation

AIMS

The predictive role of local impedance (LI) drop in lesion formation using a novel contact force sensing ablation catheter was recently described. The purpose of our current study was to assess the temporal characteristics of LI drop during ablation and its correlation with acute lesion efficacy.

METHODS AND RESULTS

Point-by-point pulmonary vein isolation was performed. The efficacy of applications was determined by pacing along the circular ablation line and assessing loss of capture. Local impedance, contact force, and catheter position data with high resolution were analysed and compared in successful and unsuccessful applications. Five hundred and fifty-nine successful and 84 unsuccessful applications were analysed. The successful applications showed higher baseline LI (P < 0.001) and larger LI drop during ablation (P < 0.001, for all). In case of unsuccessful applications, after a moderate but significant drop from baseline to the 2 s time point (153 vs. 145 Ω, P < 0.001), LI did not change further (P = 0.99). Contradictorily, in case of successful applications, the LI significantly decreased further (baseline-2 s-10 s: 161-150-141 Ω, P < 0.001 for all). The optimal cut-point for the LI drop indicating unsuccessful application was <9 Ω at the 4-s time point [AUC = 0.73 (0.67-0.76), P < 0.001]. Failing to reach this cut-point predicted unsuccessful applications [OR 3.82 (2.34-6.25); P < 0.001].

CONCLUSION

A rapid and enduring drop of the LI may predict effective lesion formation, while slightly changing or unchanged LI is associated with unsuccessful applications. A moderate LI drop during the first 4 s of radiofrequency application predicts ineffective radiofrequency delivery.

The effect of fixed and functional remodelling on conduction velocity, wavefront propagation, and rotational activity formation in atrial fibrillation

AIMS

Pathophysiology of atrial fibrillation (AF) remains unclear. Interactions between scar and conduction velocity (CV) and their impact on wavefront propagation in sinus rhythm (SR) and rotational activity burden in AF were evaluated.

METHODS AND RESULTS

Local activation times (LATs) and voltage data were obtained from patients undergoing ablation for persistent AF. Omnipolar voltage (OV) and bipolar voltage (BV) data were obtained during AF and SR at pacing intervals of 600 and 250 ms. Local activation times were used to determine CV dynamics and their relationship to the underlying voltage and pivot points in SR. Computational modelling studies were performed to evaluate the impact of CVs and fibrosis on rotational activity burden in AF. Data from 60 patients with a total of 2 768 400 LAT and voltage points were analysed (46 140 ± 5689 points/patient). Voltage determined CV dynamics. Enhanced CV heterogeneity sites were predominantly mapped to low-voltage zones (LVZs) (0.2-0.49 mV) (128/168, 76.2%) rather than LVZs (<0.2 mV) and frequently co-located to pivot points (151/168, 89.9%). Atrial fibrillation OV maps correlated better with SR BV 250 ms than 600 ms maps, thereby representing fixed and functional remodelling. Sinus rhythm maps at 250 ms compared with 600 ms harboured a greater number of pivot points. Increased CV slowing and functional remodelling on computational models resulted in a greater rotational activity burden.

CONCLUSION

Conduction velocity dynamics are impacted by the degree of scar. Conduction velocity heterogeneity and functional remodelling impacts wavefront propagation in SR and rotational activity burden in AF. This study provides insight into the pathophysiology of AF and identifies potential novel ablation targets.

Role of Steroid Therapy in Preventing Recurrence of Atrial Fibrillation After Ablation: A Systematic Review and Meta-Analysis

Atrial fibrillation (AF) is the most common cardiac arrhythmia with challenging management due to its potential complications and high recurrence rates. Catheter ablation is a standard treatment option for symptomatic patients, particularly those unresponsive to medical management but has variable success rates. Inflammation plays a critical role in the pathogenesis and persistence of AF. This systematic review aims to study the potential benefits of corticosteroid use in the prevention of AF recurrence after procedures such as catheter ablation, providing a more comprehensive understanding of their role in improving outcomes. Four randomized controlled trials (RCTs) with 824 total participants and four cohort studies with 1128 participants were included for qualitative and quantitative analysis. All RCTs and cohort studies suggest no significant benefit of corticosteroids with ablation in preventing short-term (less than three months) AF recurrence. However, RCTs indicate that corticosteroid use with ablation significantly reduces the recurrence of AF over three months, but such a statistically significant effect is not seen in cohort studies for AF recurrence up to one year. This suggests that there might be some beneficial role of using steroids with ablation procedures in preventing recurrences of AF, but further large-scale studies are warranted for better evidence to support the use of steroids with ablation. Future research should focus on understanding the optimal duration and dosing of corticosteroid treatment to maximize benefits and minimize risks, especially in the immediate post-treatment period where the data currently show less clarity and higher variability. Additionally, further studies should explore the mechanisms through which corticosteroids exert their effects over different durations to better tailor treatment protocols.

Cryoballoon pulmonary vein isolation as first-line treatment of typical atrial flutter: long-term outcomes of the CRAFT trial

BACKGROUND

CRAFT was an international, multicentre, randomised controlled trial across 11 sites in the United UK and Switzerland. Given the evidence that pulmonary vein triggers may be responsible for atrial flutter (AFL) as well as atrial fibrillation (AF), we hypothesised that cryoballoon pulmonary vein isolation (PVI) would provide greater symptomatic arrhythmia reduction than cavotricuspid isthmus (CTI) ablation, whilst also reducing the subsequent burden of AF. Twelve-month outcomes were previously reported. In this study, we report the extended outcomes of the CRAFT study to 36 months.

METHODS

Patients with typical AFL and no evidence of AF were randomised 1:1 to cryoballoon PVI or radiofrequency CTI. All patients received an implantable loop recorder (ILR) for continuous cardiac rhythm monitoring. The primary outcome was time-to-symptomatic arrhythmia recurrence > 30 s. Secondary outcomes included time-to-first-AF episode ≥ 2 min. The composite safety outcome included death, stroke and procedural complications.

RESULTS

A total of 113 patients were randomised to cryoballoon PVI (n = 54) or radiofrequency CTI ablation (n = 59). Ninety-one patients reconsented for extended follow-up beyond 12 months. There was no difference in the primary outcome between arms, with the primary outcome occurring in 12 PVI vs 11 CTI patients (HR 0.97; 95% CI 0.43-2.20; p = 0.994). AF ≥ 2 min was significantly less frequent in the PVI arm, affecting 26 PVI vs 36 CTI patients (HR 0.48; 95% CI 0.29-0.79; p = 0.004). The composite safety outcome occurred in 5 PVI and 6 CTI patients (p = 0.755).

CONCLUSION

Cryoballoon PVI shows similar efficacy to radiofrequency CTI ablation in reducing symptomatic arrhythmia recurrence in patients presenting with isolated typical AFL but significantly reduces the occurrence of subsequent AF.

Clinical decisions for appropriate management of patients with atrial fibrillation

The management of patients with atrial fibrillation (AF) requires intricate clinical decision-making to optimize outcomes. In everyday clinical practice, physicians undergo difficult choices to better manage patients with AF. They need to balance thromboembolic and bleeding risk to focus on patients' symptoms and to manage a variety of multiple comorbidities. In this review, we aimed to explore the multifaceted dimensions of clinical decision-making in AF patients, encompassing the definition and diagnosis of clinical AF, stroke risk stratification, oral anticoagulant therapy selection, consideration of bleeding risk, and the ongoing debate between rhythm and rate control strategies. We will also focus on possible grey zones for the management of AF patients. In navigating this intricate landscape, clinicians must reconcile the dynamic interplay of patient-specific factors, evolving guidelines, and emerging therapies. The review underscores the need for personalized, evidence-based clinical decision-making to tailor interventions for optimal outcomes according to specific AF patient profiles.

Pulsed-field- vs. cryoballoon-based pulmonary vein isolation: lessons from repeat procedures

AIMS

Pulsed-field ablation (PFA) is an emerging technology to perform pulmonary vein isolation (PVI). Initial data demonstrated high safety and efficacy. Data on long-term PVI durability and reconduction patterns in comparison to established energy sources for PVI are scarce. We compare findings in repeat ablation procedures after a first PFA to findings in repeat ablation procedures after a first cryoballoon ablation (CBA) based PVI.

METHODS AND RESULT

A total of 550 consecutively enrolled patients underwent PFA or CBA index PVI. Repeat ablations in patients with symptomatic atrial arrhythmia recurrences were analysed. A total of 22/191 (12%) patients after index PFA-PVI and 44/359 (12%) after CBA-PVI underwent repeat ablation. Reconduction of any pulmonary vein (PV) was detected by multipolar spiral mapping catheter at each PV with careful evaluation of PV potentials and by 3D-mapping in 16/22 patients (73%) after PFA-PVI and in 33/44 (75%) after CBA-PVI (P = 1.000). Of 82 initially isolated PVs after PFA-PVI, 31 (38%) were reconducting; of 169 isolated PVs after CBA-PVI, 63 (37%) were reconducting (P = 0.936). Clinical atrial tachycardia occurred similarly in patients after PFA (5/22; 23%) and CBA (7/44; 16%; P = 0.515). Roof lines were set more often after PFA- (8/22; 36%) compared with CBA-PVI (5/44; 11%; P = 0.023). Repeat procedure duration [PFA: 87 (76, 123) min; CBA: 93 (75, 128) min; P = 0.446] was similar and fluoroscopy time [PFA: 11 (9, 14) min; CBA: 11 (8, 14) min; P = 0.739] equal between groups at repeat ablation.

CONCLUSION

During repeat ablation after previous PFA- or CBA-based PVI, electrical PV-reconduction rates and patterns were similar.

Application repetition and electrode-tissue contact result in deeper lesions using a pulsed-field ablation circular variable loop catheter

AIMS

Pulsed-field ablation (PFA) is a novel, myocardial-selective, non-thermal ablation modality used to target cardiac arrhythmias. Although prompt electrogram (EGM) signal disappearance is observed immediately after PFA application in the pulmonary veins, whether this finding results in adequate transmural lesions is unknown. The aim of this study is to check whether application repetition and catheter-tissue contact impact lesion formation during PFA.

METHODS AND RESULTS

A circular loop PFA catheter was used to deliver repeated energy applications with various levels of contact force. A benchtop vegetal potato model and a beating heart ventricular myocardial model were utilized to evaluate the impact of application repetition, contact force, and catheter repositioning on contiguity and lesion depth. Lesion development occurred over 18 h in the vegetal model and over 6 h in the porcine model. Lesion formation was found to be dependent on application repetition and contact. In porcine ventricles, single and multiple stacked applications led to a lesion depth of 3.5 ± 0.7 and 4.4 ± 1.3 mm, respectively (P = 0.002). Furthermore, the greater the catheter-tissue contact, the more contiguous and deeper the lesions in the vegetal model (1.0 ± 0.9 mm with no contact vs. 5.4 ± 1.4 mm with 30 g of force; P = 0.0001).

CONCLUSION

Pulsed-field ablation delivered via a circular catheter showed that both repetition and catheter contact led independently to deeper lesion formation. These findings indicate that endpoints for effective PFA are related more to PFA biophysics than to mere EGM attenuation.

Disparities in the access to atrial fibrillation ablation in Denmark: who gets ablated, who neglected?

AIMS

Atrial fibrillation (AF) is a common arrhythmia associated with reduced quality of life that can lead to serious complications such as stroke and heart failure. Ablation is a safe and effective treatment for AF but is not offered equally to all patients. The aim of this study is to identify demographic groups more or less likely to undergo AF ablation.

METHODS AND RESULTS

All patients with newly diagnosed AF between 2010 and 2018 were identified in the Danish nationwide registries. The association between gender, age, level of education and attachment to the job market, and the likelihood of receiving AF ablation was investigated using multivariable Cox proportional hazard analysis. Cumulative incidence was calculated using the Aalen-Johansen estimator. A total of 176 248 patients were included. Men were more likely to receive ablation than women (7% vs. 3%). Patients aged 25-44 and 45-64 were most likely to receive ablation, while only 0.7% of patients aged 80 or above received ablation. The rate of ablation significantly decreased with decreasing level of education. Full-time employed patients were most likely to receive ablation, followed by self-employed, unemployed, on sick leave, undergoing education, and early retired patients. Retired patients were the least likely to receive ablation (3%).

CONCLUSION

This study found that women, older patients, patients with lower levels of education, and patients on social benefits are less likely to receive AF ablation. These findings suggest that there are significant social and economic disparities in AF ablation treatment in Denmark.

Insights into the prospects of nanobiomaterials in the treatment of cardiac arrhythmia

Cardiac arrhythmia, a disorder of abnormal electrical activity of the heart that disturbs the rhythm of the heart, thereby affecting its normal function, is one of the leading causes of death from heart disease worldwide and causes millions of deaths each year. Currently, treatments for arrhythmia include drug therapy, radiofrequency ablation, cardiovascular implantable electronic devices (CIEDs), including pacemakers, defibrillators, and cardiac resynchronization therapy (CRT). However, these traditional treatments have several limitations, such as the side effects of medication, the risks of device implantation, and the complications of invasive surgery. Nanotechnology and nanomaterials provide safer, effective and crucial treatments to improve the quality of life of patients with cardiac arrhythmia. The large specific surface area, controlled physical and chemical properties, and good biocompatibility of nanobiomaterials make them promising for a wide range of applications, such as cardiovascular drug delivery, tissue engineering, and the diagnosis and therapeutic treatment of diseases. However, issues related to the genotoxicity, cytotoxicity and immunogenicity of nanomaterials remain and require careful consideration. In this review, we first provide a brief overview of cardiac electrophysiology, arrhythmia and current treatments for arrhythmia and discuss the potential applications of nanobiomaterials before focusing on the promising applications of nanobiomaterials in drug delivery and cardiac tissue repair. An in-depth study of the application of nanobiomaterials is expected to provide safer and more effective therapeutic options for patients with cardiac arrhythmia, thereby improving their quality of life.

Challenging the status quo: a scoping review of value-based care models in cardiology and electrophysiology

AIMS

The accomplishment of value-based healthcare (VBHC) models could save up to $1 trillion per year for healthcare systems worldwide while improving patients' wellbeing and experience. Nevertheless, its adoption and development are challenging. This review aims to provide an overview of current literature pertaining to the implementation of VBHC models used in cardiology, with a focus on cardiac electrophysiology.

METHODS AND RESULTS

This scoping review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-analysis for Scoping Reviews. The records included in this publication were relevant documents published in PubMed, Mendeley, and ScienceDirect. The search criteria were publications about VBHC in the field of cardiology and electrophysiology published between 2006 and 2023. The implementation of VBHC models in cardiology and electrophysiology is still in its infant stages. There is a clear need to modify the current organizational structure in order to establish cross-functional teams with the patient at the centre of care. The adoption of new reimbursement schemes is crucial to moving this process forward. The implementation of technologies for data analysis and patient management, among others, poses challenges to the change process.

CONCLUSION

New VBHC models have the potential to improve the care process and patient experience while optimizing the costs. The implementation of this model has been insufficient mainly because it requires substantial changes in the existing infrastructures and local organization, the need to track adherence to guidelines, and the evaluation of the quality of life improvement and patient satisfaction, among others.

Trends in atrial fibrillation-related mortality in Europe, 2008-2019

AIMS

Update data regarding the atrial fibrillation (AF)-related mortality trend in Europe remain scant. We assess the age- and sex-specific trends in AF-related mortality in the European states between the years 2008 and 2019.

METHODS AND RESULTS

Data on cause-specific deaths and population numbers by sex for European countries were retrieved through the publicly available World Health Organization mortality dataset for the years 2008-2019. Atrial fibrillation-related deaths were ascertained when the International Classification of Diseases, 10th Revision code I48 was listed as the underlying cause of death in the medical death certificate. To calculate annual trends, we assessed the average annual % change (AAPC) with relative 95% confidence intervals (CIs) using Joinpoint regression. During the study period, 773 750 AF-related deaths (202 552 males and 571 198 females) occurred in Europe. The age-adjusted mortality rate (AAMR) linearly increased from 12.3 (95% CI: 11.2-12.9) per 100 000 population in 2008 to 15.3 (95% CI: 14.7-15.7) per 100 000 population in 2019 [AAPC: +2.0% (95% CI: 1.6-3.5), P < 0.001] with a more pronounced increase among men [AAPC: +2.7% (95% CI: 1.9-3.5), P < 0.001] compared with women [AAPC: +1.7% (95% CI: 1.1-2.3), P < 0.001] (P for parallelism 0.01). Higher AAMR increases were observed in some Eastern European countries such as Latvia, Lithuania, and Poland, while the lower increases were mainly clustered in Central Europe.

CONCLUSION

Over the last decade, the age-adjusted AF-related mortality has increased in Europe, especially among males. Disparities still exist between Western and Eastern European countries.

Same-day discharge vs. overnight stay following catheter ablation for atrial fibrillation: a comprehensive review and meta-analysis by the European Heart Rhythm Association Health Economics Committee

AIMS

Same-day discharge (SDD) after catheter ablation of atrial fibrillation (AF) may address the growing socio-economic health burden of the increasing demand for interventional AF therapies. This systematic review and meta-analysis analyses the current evidence on clinical outcomes in SDD after AF ablation compared with overnight stay (ONS).

METHODS AND RESULTS

A systematic search of the PubMed database was performed. Pre-defined endpoints were complications at short-term (24-96 h) and 30-day post-discharge, re-hospitalization, and/or emergency room (ER) visits at 30-day post-discharge, and 30-day mortality. Twenty-four studies (154 716 patients) were included. Random-effects models were applied for meta-analyses of pooled endpoint prevalence in the SDD cohort and for comparison between SDD and ONS cohorts. Pooled estimates for complications after SDD were low both for short-term [2%; 95% confidence interval (CI): 1-5%; I2: 89%) and 30-day follow-up (2%; 95% CI: 1-4%; I2: 91%). There was no significant difference in complications rates between SDD and ONS [short-term: risk ratio (RR): 1.62; 95% CI: 0.52-5.01; I2: 37%; 30 days: RR: 0.65; 95% CI: 0.42-1.00; I2: 95%). Pooled rates of re-hospitalization/ER visits after SDD were 4% (95% CI: 1-10%; I2: 96%) with no statistically significant difference between SDD and ONS (RR: 0.86; 95% CI: 0.58-1.27; I2: 61%). Pooled 30-day mortality was low after SDD (0%; 95% CI: 0-1%; I2: 33%). All studies were subject to a relevant risk of bias, mainly due to study design.

CONCLUSION

In this meta-analysis including a large contemporary cohort, SDD after AF ablation was associated with low prevalence of post-discharge complications, re-hospitalizations/ER visits and mortality, and a similar risk compared with ONS. Due to limited quality of current evidence, further prospective, randomized trials are needed to confirm safety of SDD and define patient- and procedure-related prerequisites for successful and safe SDD strategies.

State-of-the-art pulsed field ablation for cardiac arrhythmias: ongoing evolution and future perspective

Pulsed field ablation (PFA) is an innovative approach in the field of cardiac electrophysiology aimed at treating cardiac arrhythmias. Unlike traditional catheter ablation energies, which use radiofrequency or cryothermal energy to create lesions in the heart, PFA utilizes pulsed electric fields to induce irreversible electroporation, leading to targeted tissue destruction. This state-of-the-art review summarizes biophysical principles and clinical applications of PFA, highlighting its potential advantages over conventional ablation methods. Clinical data of contemporary PFA devices are discussed, which combine predictable procedural outcomes and a reduced risk of thermal collateral damage. Overall, these technological developments have propelled the rapid evolution of contemporary PFA catheters, with future advancements potentially impacting patient care.

Randomized Study Comparing Radiofrequency Ablation with the PVAC Gold System vs. Antiarrhythmic Drugs in Elderly Patients with Symptomatic Atrial Fibrillation

BACKGROUND

There are no randomized studies comparing the maintenance of sinus rhythm after catheter ablation (CA) concerning treatment with antiarrhythmic drugs (AA) in elderly patients with paroxysmal atrial fibrillation (AF).

OBJECTIVES

To compare the clinical results of pulmonary vein (PV) isolation with the second-generation PVAC Gold catheter against AA treatment in elderly people with recurrent symptomatic paroxysmal AF, refractory to at least one AA, and without structural heart disease.

METHODS

Sixty patients with paroxysmal AF ≥ 65 years old were randomized to two forms of treatment: group 1: CA and group 2: AA drugs. The primary outcome was the AF recurrence-free rate after at least one year of follow-up. Secondary outcomes were: progression to persistent forms of AF, impact on quality of life (QOLF), and complications. The significance level adopted in the statistical analysis was 5% (p<0.05).

RESULTS

The AF recurrence-free rate was 80% (10% with amiodarone) in the CA group, after 1.3 procedures per patient and 65% in the AA group (60% with amiodarone), (p = 0.119) in an average follow-up of 719 days (Q1: 566; Q3: 730). The persistent AF free rate was 83.4% in the AC group and 67.7% in the AA group (p = 0.073) Both strategies showed an improvement in the AFQoL score during follow-up (p < 0.001), with no difference between the groups. Although without clinical repercussions or impact on the intellectual assessment test, 25% of patients in the CA group showed signs of cerebral embolization on brain MRI.

CONCLUSIONS

Both strategies for maintaining sinus rhythm promoted an improvement in the quality of life of elderly patients with symptomatic AF, with no statistical difference in the clinical outcomes. Additional studies using technologies with a better safety profile are needed to evaluate the benefits of CA in elderly patients with AF.

Pulmonary Vein Isolation with Pulsed Field Ablation and Size-Adjustable Cryo-Balloon: A Comparative Procedural Analysis of First-Time Use

Background: Pulmonary vein isolation (PVI) is the standard of care for the treatment of symptomatic atrial fibrillation (AF). Novel techniques for PVI are the thermal size-adjustable cryo-balloon (CB) system and non-thermal pulsed field ablation (PFA) system. There are currently no data available for a direct comparison between these two systems. Furthermore, with new techniques, it is important to ensure a high level of efficiency and safety during treatment right from initial use. Therefore, the aim of this study was to directly compare the procedural data and safety of these two new PVI techniques in first-time users. Methods: We conducted a single-center prospective study involving 100 consecutive patients with symptomatic atrial fibrillation who underwent first-time PVI using either size-adjustable CB PVI or PFA PVI from July 2023 to March 2024. Results: Acute PVI was achieved in 100% of patients in both groups. First-pass isolation (FPI) was more frequently achieved in the PFA group compared to the size-adjustable CB group. The mean procedural duration and fluoroscopy dose were significantly shorter in the PFA cohort (p < 0.001). Furthermore, a significant reduction in fluoroscopy time was observed during the learning curve within the PFA group (p = 0.023). There were no major complications in both groups. Conclusions: Both systems demonstrate good effectiveness and safety during PVI performed by first-time users. However, the PFA group exhibited a significantly shorter procedural duration.

Heart Failure-Related Death in Subjects With Atrial Fibrillation in the United States, 1999 to 2020

BACKGROUND

Population-based data on heart failure (HF)-related death in patients with atrial fibrillation (AF) are lacking. We assessed HF-related death in people with AF in the United States over the past 21 years and examined differences by age, sex, race, ethnicity, urbanization, and census region.

METHODS AND RESULTS

Data were extracted from the Centers for Disease Control and Prevention Wide-Ranging Online Data for Epidemiologic Research to determine trends in age-adjusted mortality rates per 100 000 people, due to HF-related death among subjects with AF aged ≥15 years. To calculate nationwide annual trends, we assessed the average annual percent change (AAPC) and annual percent change with relative 95% CIs using joinpoint regression. Between 1999 and 2020, 916 685 HF-related deaths (396 205 men and 520 480 women) occurred among US adults having a concomitant AF. The overall age-adjusted mortality rates increased (AAPC: +4.1% [95% CI, 3.8-4.4]; P<0.001), especially after 2011 (annual percent change, +6.8% [95% CI, 6.2-7.4]; P<0.001) in men (AAPC, +4.8% [95% CI, 4.4-5.1]; P<0.001), in White subjects (AAPC: +4.2% [95% CI, 3.9 to 4.6]; P<0.001) and in subjects aged <65 years (AAPC: +7.5% [95% CI, 6.7-8.4]; P<0.001). The higher percentage of deaths were registered in the South (32.8%). During the first year of the COVID-19 pandemic, a significant excess in HF-related deaths among patients with AF aged >65 years was observed.

CONCLUSIONS

A worrying increase in the HF-related mortality rate among patients with AF has been observed in the United States over the past 2 decades.

Dual energy for pulmonary vein isolation using dual-energy focal ablation technology integrated with a three-dimensional mapping system: SmartfIRE 3-month results

AIMS

Contact force (CF)-sensing radiofrequency (RF) catheters with an ablation index have shown reproducible outcomes for the treatment of atrial fibrillation (AF) in large multicentre studies. A dual-energy (DE) focal CF catheter to deliver RF and unipolar/biphasic pulsed field ablation (PFA), integrated with a three-dimensional (3D) mapping system, can provide operators with additional flexibility. The SmartfIRE study assessed the safety and efficacy of this novel technology for the treatment of drug-refractory, symptomatic paroxysmal AF. Results at 3 months post-ablation are presented here.

METHODS AND RESULTS

Pulmonary vein isolation (PVI) was performed using a DE focal, irrigated CF-sensing catheter with the recommendation of PFA at posterior/inferior and RF ablation at the anterior/ridge/carina segments. Irrespective of energy, a tag size of 3 mm; an inter-tag distance ≤6 mm; a target index of 550 for anterior, roof, ridge, and carina; and a target index of 400 for posterior and inferior were recommended. Cavotricuspid isthmus ablation was permitted in patients with documented typical atrial flutter. The primary effectiveness endpoint was acute procedural success. The primary safety endpoint was the rate of primary adverse events (PAEs) within 7 days of the procedure. A prespecified patient subset underwent oesophageal endoscopy (EE; 72 h post-procedure), neurological assessment (NA; pre-procedure and discharge), and cardiac computed tomography (CT)/magnetic resonance angiogram (MRA) imaging (pre-procedure and 3 months post-procedure) for additional safety evaluation, and a mandatory remapping procedure (Day 75 ± 15) for PVI durability assessment. Of 149 patients enrolled between February and June 2023, 140 had the study catheter inserted (safety analysis set) and 137 had ablation energy delivered (per-protocol analysis set). The median (Q1/Q3) total procedure and fluoroscopy times were 108.0 (91.0/126.0) and 4.2 (2.3/7.7) min (n = 137). The acute procedural success rate was 100%. First-pass isolation was achieved in 89.1% of patients and 96.8% of veins. Cavotricuspid isthmus ablations were successfully performed in 12 patients [pulsed field (PF) only: 6, RF only: 5, and RF/PF: 1]. The PAE rate was 4.4% [6/137 patients; 2 pulmonary vein (PV) stenoses, 2 cardiac tamponades/perforations, 1 stroke, and 1 pericarditis]. No coronary artery spasm was reported. No oesophageal lesion was seen in the EE subset (0/31, 0%). In the NA subset (n = 30), microemboli lesions were identified in 2 patients (2/30, 6.7%), both of which were resolved at follow-up; only 1 was symptomatic (silent cerebral lesion, 3.3%). In the CT/MRA subset (n = 30), severe PV narrowing (of >70%) was detected in 2 patients (2/30, 6.7%; vein level 2/128, 1.6%), of whom 1 underwent dilatation and stenting and 1 was asymptomatic; both were associated with high index values and a small inter-tag distance. In the PV durability subset (n = 30), 100/115 treated PVs (87%) were durably isolated and 18/30 patients (60.0%) had all PVs durably isolated.

CONCLUSION

A DE focal CF catheter with 3D mapping integration showed a 100% acute success rate with an acceptable safety profile in the treatment of paroxysmal AF. Prespecified 3-month remapping showed notable PVI durability.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT05752487.

Ablation of Paroxysmal Atrial Fibrillation: between Present and Future

Pulmonary vein isolation (PVI) is the established cornerstone for atrial fibrillation (AF) ablation, indeed current guidelines recognize PVI as the gold standard for first-time AF ablation, regardless of if it is paroxysmal or persistent. Since 1998 when Haïssaguerre pioneered AF ablation demonstrating a burden reduction after segmental pulmonary vein (PV) ablation, our approach to PVI was superior in terms of methodology and technology. This review aims to describe how paroxysmal atrial fibrillation ablation has evolved over the last twenty years. We will focus on available techniques, a mechanistic understanding of paroxysmal AF genesis and the possibility of a tailored approach for the treatment of AF, before concluding with a future perspective.

Application of a circular-shaped pulsed field ablation catheter with magnetic sensors for pulmonary vein isolation: a multi-centre clinical study report

AIMS

A few studies have reported the effect and safety of pulsed field ablation (PFA) catheters for ablating atrial fibrillation (AF), which were mainly based on basket-shaped or flower-shaped designs. However, the clinical application of a circular-shaped multi-electrode catheter with magnetic sensors is very limited. To study the efficacy and safety of a PFA system in patients with paroxysmal AF using a circular-shaped multi-electrode catheter equipped with magnetic sensors for pulmonary vein isolation (PVI).

METHODS AND RESULTS

A novel proprietary bipolar PFA system was used for PVI, which utilized a circular-shaped multi-electrode catheter with magnetic sensors and allowed for three-dimensional model reconstruction, mapping, and ablation in one map. To evaluate the efficacy, efficiency, and safety of this PFA system, a prospective, multi-centre, single-armed, pre-market clinical study was performed. From July 2021 to December 2022, 151 patients with paroxysmal AF were included and underwent PVI. The study examined procedure time, immediate success rate, procedural success rate at 12 months, and relevant complications. In all 151 patients, all the pulmonary veins were acutely isolated using the studied system. Pulsed field ablation delivery was 78.4 ± 41.8 times and 31.3 ± 16.7 ms per patient. Skin-to-skin procedure time was 74.2 ± 29.8 min, and fluoroscopy time was 13.1 ± 7.6 min. The initial 11 (7.2%) cases underwent procedures with deep sedation anaesthesia, and the following cases underwent local anaesthesia. In the initial 11 cases, 4 cases (36.4%) presented transient vagal responses, and the rest were all successfully preventatively treated with atropine injection and rapid fluid infusion. No severe complications were found during or after the procedure. During follow-up, 3 cases experienced atrial flutter, and 11 cases had AF recurrence. The estimated 12-month Kaplan-Meier of freedom from arrhythmia was 88.4%.

CONCLUSION

The PFA system, comprised of a circular PFA catheter with magnetic sensors, could rapidly achieve PVI under three-dimensional guidance and demonstrated excellent safety with comparable effects.

Longer and better lives for patients with atrial fibrillation: the 9th AFNET/EHRA consensus conference

AIMS

Recent trial data demonstrate beneficial effects of active rhythm management in patients with atrial fibrillation (AF) and support the concept that a low arrhythmia burden is associated with a low risk of AF-related complications. The aim of this document is to summarize the key outcomes of the 9th AFNET/EHRA Consensus Conference of the Atrial Fibrillation NETwork (AFNET) and the European Heart Rhythm Association (EHRA).

METHODS AND RESULTS

Eighty-three international experts met in Münster for 2 days in September 2023. Key findings are as follows: (i) Active rhythm management should be part of the default initial treatment for all suitable patients with AF. (ii) Patients with device-detected AF have a low burden of AF and a low risk of stroke. Anticoagulation prevents some strokes and also increases major but non-lethal bleeding. (iii) More research is needed to improve stroke risk prediction in patients with AF, especially in those with a low AF burden. Biomolecules, genetics, and imaging can support this. (iv) The presence of AF should trigger systematic workup and comprehensive treatment of concomitant cardiovascular conditions. (v) Machine learning algorithms have been used to improve detection or likely development of AF. Cooperation between clinicians and data scientists is needed to leverage the potential of data science applications for patients with AF.

CONCLUSIONS

Patients with AF and a low arrhythmia burden have a lower risk of stroke and other cardiovascular events than those with a high arrhythmia burden. Combining active rhythm control, anticoagulation, rate control, and therapy of concomitant cardiovascular conditions can improve the lives of patients with AF.

Personalized pulmonary vein isolation with very high-power short-duration lesions guided by left atrial wall thickness: the QDOT-by-LAWT randomized trial

AIMS

Pulmonary vein isolation (PVI) for paroxysmal atrial fibrillation (PAF) using very high-power short-duration (vHPSD) radiofrequency (RF) ablation proved to be safe and effective. However, vHPSD applications result in shallower lesions that might not be always transmural. Multidetector computed tomography-derived left atrial wall thickness (LAWT) maps could enable a thickness-guided switching from vHPSD to the standard-power ablation mode. The aim of this randomized trial was to compare the safety, the efficacy, and the efficiency of a LAWT-guided vHPSD PVI approach with those of the CLOSE protocol for PAF ablation (NCT04298177).

METHODS AND RESULTS

Consecutive patients referred for first-time PAF ablation were randomized on a 1:1 basis. In the QDOT-by-LAWT arm, for LAWT ≤2.5 mm, vHPSD ablation was performed; for points with LAWT > 2.5 mm, standard-power RF ablation titrating ablation index (AI) according to the local LAWT was performed. In the CLOSE arm, LAWT information was not available to the operator; ablation was performed according to the CLOSE study settings: AI ≥400 at the posterior wall and ≥550 at the anterior wall. A total of 162 patients were included. In the QDOT-by-LAWT group, a significant reduction in procedure time (40 vs. 70 min; P < 0.001) and RF time (6.6 vs. 25.7 min; P < 0.001) was observed. No difference was observed between the groups regarding complication rate (P = 0.99) and first-pass isolation (P = 0.99). At 12-month follow-up, no significant differences occurred in atrial arrhythmia-free survival between groups (P = 0.88).

CONCLUSION

LAWT-guided PVI combining vHPSD and standard-power ablation is not inferior to the CLOSE protocol in terms of 1-year atrial arrhythmia-free survival and demonstrated a reduction in procedural and RF times.

Procedural performance and outcome after pulsed field ablation for pulmonary vein isolation: comparison with a reference radiofrequency database

Aims

Pulsed field ablation (PFA) is a promising ablation technique for pulmonary vein isolation (PVI) with appealing advantages over radiofrequency (RF) including speed, tissue selectivity, and the promise of enhanced durability. In this study, we determine the procedural performance, efficacy, safety, and durability of PFA and compare its performance with a dataset of optimized RF ablation.

Methods and results

After propensity score matching, we compared 161 patients who received optimized RF-guided PVI in the PowerPlus study (CLOSE protocol) with 161 patients undergoing PFA-guided PVI for paroxysmal or persistent atrial fibrillation (AF; pentaspline basket catheter). The median age was 65 years with 78% paroxysmal AF in the PFA group (comparable characteristics in the RF group). Pulsed field ablation-guided PVI was obtained in all patients with a procedure time of 47 min (vs. 71 min in RF, P < 0.0001) and a fluoroscopy time of 15 min (vs. 11 min in RF, P < 0.0001). One serious adverse event [transient ischaemic attack] occurred in a patient with thrombocytosis (0.6 vs. 0% in RF). During the 6-month follow-up, 24 and 27 patients experienced a recurrence with 20 and 11 repeat procedures in the PFA and the RF groups, respectively (P = 0.6 and 0.09). High-density mapping revealed a status of 4 isolated veins in 7/20 patients in the PFA group and in 2/11 patients in the RF group (35 vs. 18%, P = 0.3).

Conclusion

Pulsed field ablation fulfils the promise of offering a short and safe PVI procedure, even when compared with optimized RF in experienced hands. Pulmonary vein reconnection is the dominant cause of recurrence and tempers the expectation of a high durability rate with PFA.

Role of electroanatomical mapping-guided superior vena cava isolation in paroxysmal atrial fibrillation patients without provoked superior vena cava triggers: a randomized controlled study

AIMS

Data about whether empirical superior vena cava (SVC) isolation (SVCI) improves the success rate of paroxysmal atrial fibrillation (PAF) are conflicting. This study sought to first investigate the characteristics of SVC-triggered atrial fibrillation and secondly investigate the impact of electroanatomical mapping-guided SVCI, in addition to circumferential pulmonary vein isolation (CPVI), on the outcome of PAF ablation in the absence of provoked SVC triggers.

METHODS AND RESULTS

A total of 130 patients undergoing PAF ablation underwent electrophysiological studies before ablation. In patients for whom SVC triggers were identified, SVCI was performed in addition to CPVI. Patients without provoked SVC triggers were randomized in a 1:1 ratio to CPVI plus SVCI or CPVI only. The primary endpoint was freedom from any documented atrial tachyarrhythmias lasting over 30 s after a 3-month blanking period without anti-arrhythmic drugs at 12 months after ablation. Superior vena cava triggers were identified in 30 (23.1%) patients with PAF. At 12 months, 93.3% of those with provoked SVC triggers who underwent CPVI plus SVCI were free from atrial tachyarrhythmias. In patients without provoked SVC triggers, SVCI, in addition to CPVI, did not increase freedom from atrial tachyarrhythmias (87.9 vs. 79.6%, log-rank P = 0.28).

CONCLUSION

Electroanatomical mapping-guided SVCI, in addition to CPVI, did not increase the success rate of PAF ablation in patients who had no identifiable SVC triggers.

REGISTRATION

ChineseClinicalTrials.gov: ChiCTR2000034532.

Prevention of venous thromboembolism in right heart-sided electrophysiological procedures: results of an European Heart Rhythm Association survey

Limited data are available regarding venous thromboembolism (VTE), specifically deep vein thrombosis (DVT) and pulmonary embolism (PE), following right-sided ablations and electrophysiological (EP) studies. Compared to left-sided procedures, no guidelines on antithrombotic management strategies for the prevention of DVT and PE are available. The main purpose of the present European Heart Rhythm Association (EHRA) survey is to report the current management of right-sided EP procedures, focusing on anticoagulation and prevention of VTE. An online survey was conducted using the EHRA infrastructure. A total of 244 participants answered a 19-items questionnaire on the periprocedural management of EP studies and right-sided catheter ablations. The right femoral vein is the most common access for EP studies and right-sided procedures. An ultrasound-guided approach is employed by more than 2/3 of respondents. Intravenous heparin is not commonly given by the majority of participants. About 1/3 of participants (34%) routinely prescribe VTE prophylaxis during (mostly aspirin and low molecular weight heparin) and 1/4 of respondents (25%) commonly prescribe VTE prophylaxis after discharge (mostly aspirin). Of note, respectively 13% and 9% of participants observed at least one DVT and one PE related to right-sided ablation or EP study within the last year in their center. The present survey shows that only a minority of operators routinely gives intraprocedural intravenous heparin and prescribes VTE prophylaxis after right-sided EP procedures. Compared to left-sided procedures like atrial fibrillation (AF) ablation, there are no consistent systematic antithrombotic management strategies.

Length of hospital stay for elective electrophysiological procedures: a survey from the European Heart Rhythm Association

AIMS

Electrophysiological (EP) operations that have traditionally involved long hospital lengths of stay (LOS) are now being undertaken as day case procedures. The coronavirus disease-19 pandemic served as an impetus for many centres to shorten LOS for EP procedures. This survey explores LOS for elective EP procedures in the modern era.

METHODS AND RESULTS

An online survey consisting of 27 multiple-choice questions was completed by 245 respondents from 35 countries. With respect to de novo cardiac implantable electronic device (CIED) implantations, day case procedures were reported for 79.5% of implantable loop recorders, 13.3% of pacemakers (PMs), 10.4% of implantable cardioverter defibrillators (ICDs), and 10.2% of cardiac resynchronization therapy (CRT) devices. With respect to CIED generator replacements, day case procedures were reported for 61.7% of PMs, 49.2% of ICDs, and 48.2% of CRT devices. With regard to ablations, day case procedures were reported for 5.7% of atrial fibrillation (AF) ablations, 10.7% of left-sided ablations, and 17.5% of right-sided ablations. A LOS ≥ 2 days for CIED implantation was reported for 47.7% of PM, 54.5% of ICDs, and 56.9% of CRT devices and for 54.5% of AF ablations, 42.2% of right-sided ablations, and 46.1% of left-sided ablations. Reimbursement (43-56%) and bed availability (20-47%) were reported to have no consistent impact on the organization of elective procedures.

CONCLUSION

There is a wide variation in the LOS for elective EP procedures. The LOS for some procedures appears disproportionate to their complexity. Neither reimbursement nor bed availability consistently influenced LOS.