Patient selection, peri-procedural management, and ablation techniques for catheter ablation of atrial fibrillation: an EHRA survey

Periprocedural Safety of Interventional Electrophysiological Procedures in Octogenarians and Nonagenarians

BACKGROUND

Catheter ablation is an established treatment for cardiac arrhythmia. There is a lack of data on invasive electrophysiological (EP) procedures in aged patients.

METHODS

Consecutive patients ≥ 80 years who underwent catheter ablation or left atrial appendage closure procedures between January 2005 and December 2017 in a high-volume center were retrospectively studied and compared to a matched control group of individuals < 80 years of age.

RESULTS

The aged group consisted of 486 patients who underwent 566 procedures at a mean age of 82.7 ± 2.5 years (range 80-95 years). A cohort of 480 patients aged < 80 years (mean age 64.1 ± 13.3 years) with 566 procedures served as a control group. Performed procedures were atrial arrhythmia ablation including atrial fibrillation treatment (n = 366, 64.7%), cavotricuspid isthmus ablation (n = 139, 24.6%), ablation of ventricular arrhythmias (n = 57, 10.1%), and left atrial appendage closure (n = 12, 2.1%). There were numerically more procedures with major complications after treatment of elderly patients (32 [5.7%] vs. 21 [3.5%] procedures, p = 0.12), as well as numerically more procedures accompanied by intrahospital deaths (6 [1.1%] vs. 1 [0.2%] procedure, p = 0.12). The rate of minor complications was significantly higher in aged patients as compared to younger controls (31 [5.1%] vs. 17 [20%] procedures, p = 0.039).

CONCLUSION

Invasive EP procedures in octogenarians and nonagenarians are feasible, however a significantly higher incidence of minor periprocedural complications and a trend toward more severe complications and intrahospital fatalities were observed compared to younger patients. These findings support an individual risk-benefit assessment for elderly individuals before invasive EP treatments are conducted.

Catheter ablation for atrial fibrillation: results from a European Survey

BACKGROUND

Current data are limited regarding how electrophysiologists are integrating emerging technologies and updated atrial fibrillation (AF) guidelines into clinical practice.

OBJECTIVE

This survey aimed to analyze the peri-procedural management of patients undergoing AF ablation across Europe.

METHODS

An online-based questionnaire was conducted between September and November 2024. An additional set of questions was sent to all participants six months later.

RESULTS

A total of 203 physicians from 23 European countries participated. Fifty-three per cent had >10 years of experience as electrophysiologists, 58% worked in university hospitals, and 63% worked in centers performing over 400 procedures annually. Pre-procedural imaging is routinely used by 53%, with computed tomography being the most common modality (47.7%). General anesthesia is utilized by 42.4%, and 29.6% of physicians do not interrupt anticoagulants prior to the procedure. In paroxysmal AF ablation, pulmonary vein isolation (PVI) is the main strategy (93%). Point-by-point radiofrequency (RF) was the predominant energy source (68%), with 65% of physicians performing RF adopting a high-power strategy (>50W). For persistent AF ablation, high-density mapping catheters are used by 82.8%, and 66.4% perform additional lesions beyond PVI, most commonly targeting low-voltage areas and aiming at posterior wall isolation. Between the two phases of the survey, half of the physicians switched from RF or cryoballoon to pulsed field ablation. Intermittent use of 24-hour Holter is the primary strategy in 44.3% of cases for monitoring AF recurrence.

CONCLUSION

This survey highlights some discrepancies between the routine clinical practice of European physicians performing AF ablation and European guidelines, emphasizing the need for better integration of emerging technologies and greater adherence to updated protocols across Europe.

Early Rhythm Control for Atrial Fibrillation in Patients With End-Stage or Chronic Kidney Disease

OBJECTIVE

To investigate the benefits and risks of early rhythm control (ERC) in patients with atrial fibrillation (AF) and chronic kidney disease (CKD).

PATIENTS AND METHODS

This population-based cohort study included 5224 patients with AF (58.2% male, median age 70 years) with end-stage kidney disease (ESKD; n=1660) and CKD stage 3 to 4 (n=3564), who underwent ERC or rate control between January 1, 2005, and December 31, 2015. A primary outcome consisted of cardiovascular death, ischemic stroke, heart failure-related hospitalization, and acute myocardial infarction.

RESULTS

During a median follow-up of 3.5 years, compared with rate control, ERC was associated with a reduced risk of the primary outcome (hazard ratio [HR], 0.85; 95% CI, 0.74 to 0.98) without an increase in the composite safety outcome in CKD stage 3 to 4 (HR, 0.99; 95% CI, 0.86 to 1.13). In patients with ESKD, there was no difference between rate control and ERC in the primary outcome (HR, 0.97; 95% CI, 0.81 to 1.17) but an increase in composite safety outcome (HR, 1.29; 95% CI, 1.11 to 1.50). During follow-up, 65.0% of patients with ESKD and 57.3% with CKD stage 3 to 4 failed to maintain ERC. In the on-treatment (HR, 0.79; 95% CI, 0.62 to 0.99) and time-varying regression (HR, 0.81; 95% CI, 0.68 to 0.98) analyses, ERC was associated with a lower risk of primary outcome even in patients with ESKD.

CONCLUSION

Early rhythm control revealed a modest risk-benefit profile in patients with ESKD compared with CKD stage 3 to 4, with poor adherence to ERC playing a major role. Therefore, an approach tailored to renal function should be considered for choosing AF treatment strategies.

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.

[Initial ablation of atrial fibrillation-Is pulmonary vein isolation sufficient? : Pro and contra]

Pulmonary vein isolation (PVI) is currently the gold standard for the ablation of atrial fibrillation (AF). Although this procedure shows good success rates, the recurrence rates after PVI alone are significantly higher in advanced AF and in the presence of comorbidities. Therefore, it is important to consider additional arrhythmogenic mechanisms outside the pulmonary veins, depending on the individual case, in order to improve the patients' outcome.

An economic evaluation of first-line cryoballoon ablation versus antiarrhythmic drug therapy for the treatment of paroxysmal atrial fibrillation from a German healthcare payer perspective

BACKGROUND

Three recent randomized controlled trials demonstrated that, in patients with symptomatic paroxysmal atrial fibrillation (PAF), first-line pulmonary vein isolation with cryoballoon catheter ablation reduces atrial arrhythmia recurrence compared to initial antiarrhythmic drug (AAD) therapy. This study aimed to evaluate the cost-effectiveness of first-line cryoablation compared to first-line AADs from a German healthcare payer perspective.

METHODS

Individual patient-level data from 703 participants with untreated PAF enrolled into three randomized clinical trials (Cryo-FIRST, STOP AF First and EARLY-AF) were used to derive parameters for the cost-effectiveness model (CEM). The CEM structure consisted of a hybrid decision tree and Markov model. The decision tree (one-year time horizon) informed initial health state allocation in the first cycle of the Markov model (40-year time horizon; three-month cycle length). Health benefits were expressed in quality-adjusted life years (QALYs). Cost inputs were sourced from German diagnosis-related groups and the Institute for the Hospital Remuneration System (InEK). Costs and benefits were discounted at 3% per annum.

RESULTS

Cryoablation was cost-effective, incurring ~ €200 per patient while offering an increase in QALYs (~ 0.18) over a lifetime. This produced an average incremental cost-effectiveness ratio of ~ €1,000 per QALY gained. Individuals were expected to receive ~ 1.2 ablations over a lifetime, regardless of initial treatment. However, those initially treated with cryoablation as opposed to AADs experience 0.9 fewer re-ablations and a 45% reduction in time spent in AF health states.

CONCLUSION

Initial rhythm control with cryoballoon ablation in symptomatic PAF is a cost-effective treatment option in a German healthcare setting.

General anaesthesia and deep sedation for monopolar pulsed field ablation using a lattice-tip catheter combined with a novel three-dimensional mapping system

AIMS

A novel three-dimensional mapping platform combined with a lattice-tip catheter that can toggle between monopolar pulsed field ablation (PFA) and radiofrequency energy delivery was recently launched. So far, the system was predominantly applied in general anaesthesia (GA), not in deep sedation.

METHODS AND RESULTS

Patients with symptomatic paroxysmal or persistent atrial fibrillation (AF) were enrolled, and pulmonary vein isolation (PVI) and ablation of additional linear lesion sets were performed either in GA or in deep sedation. Pulsed field ablation was applied exclusively to perform ipsilateral PVI. A total of 63 patients (35% female, 75% persistent AF, mean age 64 ± 9 years) were included in the analysis with 23 patients treated in GA and 40 patients in deep sedation. Acute efficacy was comparable in both groups with a PVI rate of 100%. Additional 74 lesion sets were performed in the total cohort. Mean procedure and lab occupancy time in the GA and deep sedation group was 96 ± 24 min vs. 100 ± 23 min (P = 0.52) and 165 ± 40 min vs. 131 ± 35 min (P = 0.0008). Mean dose area product was 489 (216;1093) vs. 452 (272;882) cGycm2 in the GA and the deep sedation group (P = 0.82). There was one conversion from deep sedation to GA. There were no map shifts observed in any group. Pericardial tamponade occurred in one patient of the deep sedation group.

CONCLUSION

The use of a novel ablation platform in conjunction with a lattice-tip catheter in deep sedation is feasible, effective, and associated with significantly shorter lab occupancy time when compared with GA.

An international physician survey of current ablation practices in atrial fibrillation: An AIM-AF substudy

BACKGROUND

Practice guidelines recommend ablation (ABL) in atrial fibrillation (AF) for rhythm control. Guidance for antiarrhythmic drugs (AADs) post-ABL is limited.

OBJECTIVE

The purpose of this study was to determine AAD and ABL practices in the United States and Europe.

METHODS

An online survey of experienced cardiologists (CDs) (n = 360) and interventional electrophysiologists (EPs) (n = 269) was conducted. AAD- and ABL-related survey questions and responses were analyzed.

RESULTS

ABL was preferred more often as first-line AF therapy (Rx) by US CDs/EPs (P ≤.001). ABL was selected to avoid AAD Rx by 46% (50% CDs, 40% EPs); to prevent AF progression by 41% (36% CDs, 47% EPs); and for superior efficacy by 28% (27% CDs, 30% EPs). ABL was used by 9% in asymptomatic AF (9% CDs, 10% EPs), by 14% in subclinical AF (13% CDs, 14% EPs), and by 17% for first AF event (15% CDs, 18% EPs). Primary ABL was preferred in heart failure by 38%. Comorbidities, age, and left atrial size were limitations for ABL by 48%, 40%, and 38%, respectively. AADs were used after ABL for AF/atrial tachycardia (AT) prophylaxis by 34% for 3-6 months and 29% for 1-2 months. AADs were given for a single AF recurrence by 34%, bridging to re-ABL by 32%, and long-term Rx by 34%. AF/AT post-ABL was most often managed with amiodarone (42%-48%).

CONCLUSION

ABL was frequently preferred over AADs in symptomatic AF but notably also was used for asymptomatic and subclinical AF. Post-ABL AAD Rx for AF prophylaxis or recurrence was frequent, with empiric amiodarone being the most often selected AAD.

In-Hospital Pulmonary Arterial Embolism after Catheter Ablation of Over 45,000 Cardiac Arrhythmias: Individualized Case Analysis of Multicentric Data

OBJECTIVE AND BACKGROUND

 Data on incidence of in-hospital pulmonary embolisms (PE) after catheter ablation (CA) are scarce. To gain further insights, we sought to provide new findings through case-based analyses of administrative data.

METHODS

 Incidences of PE after CA of supraventricular tachycardias (SVT), atrial fibrillation (AF), atrial flutter (AFlu), and ventricular tachycardias (VT) in three German tertiary centers between 2005 and 2020 were determined and coded by the G-DRG (German Diagnosis Related Groups System) and OPS (German Operation and Procedure Classification) systems. An administrative search was performed with a consecutive case-based analysis.

RESULTS

 Overall, 47,344 ablations were analyzed (10,037 SVT; 28,048 AF; 6,252 AFlu; 3,007 VT). PE occurred in 14 (0.03%) predominantly female (n = 9; 64.3%) patients with a mean age of 55.3 ± 16.9 years, body mass index 26.2 ± 5.1 kg/m2, and left ventricular ejection fraction of 56 ± 13.6%. PE incidences were 0.05% (n = 5) for SVT, 0.02% (n = 5) for AF, and 0.13% (n = 4) for VT ablations. No patient suffered PE after AFlu ablation. Five patients (35.7%) with PE after CA had no prior indication for oral anticoagulation (OAC). Preprocedural international normalized ratio in PE patients was 1.2 ± 0.5. Most patients with PE following CA presented with symptoms the day after the procedure (n = 9) after intraprocedural heparin application of 12,943.2 ± 5,415.5 IU. PE treatment included anticoagulation with either phenprocoumon (n = 5) or non-vitamin K-dependent OAC (n = 9). Two patients with PE died after VT/AF ablation, respectively. The remaining patients were discharged without sequels.

CONCLUSION

 Over a 15-year period, incidence of PE after ablation is low, particularly low in patients with ablation for AF/AFlu. This is most likely due to stricter anticoagulation management in these patients compared with those receiving SVT/VT ablation procedures and could argue for continuation of OAC prior to ablation. Optimizing periprocedural anticoagulation management should be subject of further prospective trials.

Left Pulmonary Vein Trunk Length as a Robust Predictor of Long-Term Success of Atrial Fibrillation Catheter Ablation

Background

Radiofrequency catheter ablation (RFCA) is a commonly used treatment for atrial fibrillation (AF), but the long-term recurrence rate remains relatively high. Given the inconsistent results regarding the role of left pulmonary vein (PV) ostial anatomy in post-ablative recurrence of RFCA in previous studies, we sought to investigate the role of left PV trunk length using an alternative methodology.

Methods

A total of 369 AF patients undergoing catheter ablation were included. The left/right trunk length (LTL/RTL) of the PV was measured from pre-ablative computed tomography (CT) using three-dimensional reconstruction techniques. We constructed three multivariable Cox models, with the inclusion of the LTL, RTL, and no LTL/RTL, and used the Delong test, integrated discrimination index (IDI), and net reclassification index (NRI) to assess model improvement. We identified optimal cut-off values for LTL with the receiver operating characteristic (ROC) curve, and estimated outcomes using the Kaplan-Meier survival curve. We also used subgroup analysis to evaluate interactions.

Results

The results of the Delong test, IDI, and NRI indicated that LTL had a favorable impact on the performance of the multivariate model. Subsequently, the multivariate Cox regression analysis identified LTL as a significant risk factor for post-ablative recurrence of AF (adjusted hazard ratio (HR) = 1.08, 95% CI: 1.05-1.12, p < 0.001). According to the ROC curve, the optimal cut-off value for LTL is 11.15 mm, and the Kaplan-Meier estimator revealed different outcomes (p < 0.001). We calculated p for interaction between LTL and other factors, and no significant interaction terms were observed.

Conclusions

LTL is a robust prognostic indicator for post-ablative outcome in AF patients receiving RFCA, with a longer LTL indicating a higher risk of recurrence.

PolarX vs Arctic Front for Cryoballoon Ablation of Paroxysmal AF: The Randomized COMPARE CRYO Study

BACKGROUND

Pulmonary vein isolation is an effective treatment for atrial fibrillation (AF). Cryoballoon ablation using the Arctic Front cryoballoon (Medtronic) was found to be superior to antiarrhythmic drug treatment. Recently, a novel cryoballoon system was introduced (PolarX, Boston Scientific).

OBJECTIVES

The purpose of this study was to compare the efficacy and safety of the 2 cryoballoons in a randomized controlled trial.

METHODS

Patients with symptomatic paroxysmal AF were enrolled in 2 centers and randomized 1:1 to pulmonary vein isolation using the PolarX or the Arctic Front cryoballoon. All patients received an implantable cardiac monitor. The primary endpoint was first recurrence of atrial tachyarrhythmia (AF, atrial flutter, or atrial tachycardia [AT]) between days 91 and 365. Procedural safety was assessed by a composite of tamponade, phrenic nerve palsy lasting >24 hours, vascular complications, stroke/transient ischemic attack, atrioesophageal fistula or death up to 30 days.

RESULTS

A total of 201 patients were enrolled. At 1 year, recurrence of atrial tachyarrhythmia had occurred in 41 of 99 patients (41.6%) assigned to the PolarX group and in 48 of 102 patients (47.1%) assigned to the Arctic Front group (HR: 0.85 [95% CI: 0.56-1.30]; P = 0.03 for noninferiority; P = 0.46 for superiority). The safety endpoint occurred in 5 patients (5%) in the PolarX group (n = 5 phrenic nerve palsies lasting >24 hours), whereas no safety endpoints occurred in the Arctic Front group (P = 0.03).

CONCLUSIONS

In this randomized controlled trial using implantable cardiac monitors for continuous rhythm monitoring, the novel PolarX cryoballoon was noninferior compared with the Arctic Front cryoballoon regarding efficacy. However, the PolarX balloon resulted in significantly more phrenic nerve palsies. (Comparison of PolarX and the Arctic Front Cryoballoons for PVI in Patients With Symptomatic Paroxysmal AF [COMPARE-CRYO]; NCT04704986).

Comparison of Cryoballoon vs. Pulsed Field Ablation in Patients with Symptomatic Paroxysmal Atrial Fibrillation (SINGLE SHOT CHAMPION): Study protocol for a randomized controlled trial

Background

Single-shot devices are increasingly used for pulmonary vein isolation (PVI) in atrial fibrillation (AF). The Arctic Front cryoballoon is the most frequently used single-shot technology. A recently developed novel pulsed field ablation (PFA) device (FARAPULSE) has been introduced with the aim to improve procedural safety and efficacy.

Objective

This study will compare the novel FARAPULSE PFA device and the Arctic Front cryoballoon for first PVI in patients with symptomatic paroxysmal AF.

Methods

SINGLE SHOT CHAMPION is a multicenter, randomized controlled trial with blinded endpoint adjudication by an independent clinical events committee. Overall, 210 patients with paroxysmal AF undergoing their PVI are randomized 1:1 between PFA and cryoballoon ablation. Continuous rhythm monitoring with an implantable cardiac monitor is performed in all patients.

Results

The primary endpoint is time to first recurrence of any atrial tachyarrhythmia (AF and/or organized atrial tachyarrhythmia) lasting ≥120 seconds and identified by the implantable cardiac monitor within 91 and 365 days postablation. The composite procedural safety endpoint includes cardiac tamponade requiring drainage, persistent phrenic nerve palsy, vascular complications requiring intervention, stroke/transient ischemic attack, atrioesophageal fistula, and death occurring during or up to 30 days after the procedure. Key secondary endpoints include (1) increase in high-sensitivity troponin on day 1 postablation, (2) analysis of postablation 3-dimensional electroanatomic mapping (first 25 patients per study group), (3) AF burden, and (4) quality-of-life changes.

Conclusion

SINGLE SHOT CHAMPION will evaluate the efficacy and safety of PVI using the novel FARAPULSE PFA for patients with symptomatic paroxysmal 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.

Current management of atrial fibrillation in routine practice according to the last ESC guidelines: an EHRA physician survey-how are we dealing with controversial approaches?

AIMS

Although guidelines for the management of atrial fibrillation (AF) are regularly published, many controversial issues remain, limiting their implementation. We aim to describe current clinical practice among European Heart Rhythm Association (EHRA) community according to last guidelines.

METHODS AND RESULTS

A 30 multiple-choice questionnaire covering the most controversial topics related to AF management was distributed through the EHRA Research Network, National Societies, and social media between January and February 2023. One hundred and eighty-one physicians responded the survey, 61% from university hospitals. Atrial fibrillation screening in high-risk patients is regularly performed by 57%. Only 42% has access to at least one programme aiming at diagnosing/managing comorbidities and lifestyle modifications, with marked heterogeneity between countries. Direct oral anticoagulants are the preferred antithrombotic (97%). Rhythm control is the preferred strategy in most AF phenotypes: symptomatic vs. asymptomatic paroxysmal AF (97% vs. 77%), low vs. high risk for recurrence persistent AF (90% vs. 72%), and permanent AF (20%). I-C drugs and amiodarone are preferred while dronedarone and sotalol barely used. Ablation is the first-line therapy for symptomatic paroxysmal AF (69%) and persistent AF with markers of atrial disease (57%) and is performed independently of symptoms by 15%. In persistent AF, 68% performs only pulmonary vein isolation and 32% also additional lesions.

CONCLUSION

There is marked heterogeneity in AF management and limited accordance to last guidelines in the EHRA community. Most of the discrepancies are related to the main controversial issues, such as those related to AF screening, management of comorbidities, pharmacological treatment, and ablation strategy.

Atrial Fibrillation Ablation: Current Practice and Future Perspectives

Catheter ablation to perform pulmonary vein isolation (PVI) is established as a mainstay in rhythm control of atrial fibrillation (AF). The aim of this review is to provide an overview of current practice and future perspectives in AF ablation. The main clinical benefit of AF ablation is the reduction of arrhythmia-related symptoms and improvement of quality of life. Catheter ablation of AF is recommended, in general, as a second-line therapy for patients with symptomatic paroxysmal or persistent AF, who have failed or are intolerant to pharmacological therapy. In selected patients with heart failure and reduced left-ventricular fraction, catheter ablation was proven to reduce all-cause mortality. Also, optimal management of comorbidities can reduce AF recurrence after AF ablation; therefore, multimodal risk assessment and therapy are mandatory. To date, the primary ablation tool in widespread use is still single-tip catheter radiofrequency (RF) based ablation. Additionally, balloon-based pulmonary vein isolation (PVI) has gained prominence, especially due to its user-friendly nature and established safety and efficacy profile. So far, the cryoballoon (CB) is the most studied single-shot device. CB-based PVI is characterized by high efficiency, convincing success rates, and a beneficial safety profile. Recently, CB-PVI as a first-line therapy for AF was shown to be superior to pharmacological treatment in terms of efficacy and was shown to reduce progression from paroxysmal to persistent AF. In this context, CB-based PVI gains more and more importance as a first-line treatment choice. Non-thermal energy sources, namely pulsed-field ablation (PFA), have garnered attention due to their cardioselectivity. Although initially applied via a basket-like ablation tool, recent developments allow for point-by-point ablation, particularly with the advent of a novel lattice tip catheter.

Assessing left atrial intramyocardial fat infiltration from computerized tomography angiography in patients with atrial fibrillation

AIMS

Epicardial adipose tissue might promote atrial fibrillation (AF) in several ways, including infiltrating the underlying atrial myocardium. However, the role of this potential mechanism has been poorly investigated. The aim of this study is to evaluate the presence of left atrial (LA) infiltrated adipose tissue (inFAT) by analysing multi-detector computer tomography (MDCT)-derived three-dimensional (3D) fat infiltration maps and to compare the extent of LA inFAT between patients without AF history, with paroxysmal, and with persistent AF.

METHODS AND RESULTS

Sixty consecutive patients with AF diagnosis (30 persistent and 30 paroxysmal) were enrolled and compared with 20 age-matched control; MDCT-derived images were post-processed to obtain 3D LA inFAT maps for all patients. Volume (mL) and mean signal intensities [(Hounsfield Units (HU)] of inFAT (HU -194; -5), dense inFAT (HU -194; -50), and fat-myocardial admixture (HU -50; -5) were automatically computed by the software. inFAT volume was significantly different across the three groups (P = 0.009), with post-hoc pairwise comparisons showing a significant increase in inFAT volume in persistent AF compared to controls (P = 0.006). Dense inFAT retained a significant difference also after correcting for body mass index (P = 0.028). In addition, more negative inFAT radiodensity values were found in AF patients. Regional distribution analysis showed a significantly higher regional distribution of LA inFAT at left and right superior pulmonary vein antra in AF patients.

CONCLUSION

Persistent forms of AF are associated with greater degree of LA intramyocardial adipose infiltration, independently of body mass index. Compared to controls, AF patients present higher LA inFAT volume at left and right superior pulmonary vein antra.

Comparison of the PolarX and the Arctic Front cryoballoon for pulmonary vein isolation in patients with symptomatic paroxysmal atrial fibrillation (COMPARE CRYO) - Study protocol for a randomized controlled trial

INTRODUCTION

Single-shot devices are increasingly used for pulmonary vein isolation (PVI) in atrial fibrillation (AF). The Arctic Front cryoballoon (Medtronic) is the most frequently used single-shot technology. A recently developed novel cryoballoon has been introduced (PolarX, Boston Scientific) with the aim to address limitations of the Arctic Front system.

METHODS

COMPARE CRYO is a multicentre, randomized, controlled trial with blinded endpoint adjudication by an independent clinical events committee. A total of 200 patients with paroxysmal AF undergoing their first PVI are randomized 1:1 between PolarX cryoballoon ablation and Arctic Front cryoballoon ablation. Continuous monitoring during follow-up is performed using an implantable cardiac monitor (ICM) in all patients. The primary endpoint is time to first recurrence of any atrial tachyarrhythmia (AF, atrial flutter, and/or atrial tachycardia) ≥ 120 s between days 91 and 365 post ablation as detected on the (ICM). Procedural safety is assessed by a composite of cardiac tamponade, persistent phrenic nerve palsy >24 h, vascular complications requiring intervention, stroke/transient ischemic attack, atrioesophageal fistula or death occurring during or up to 30 days after the procedure. Key secondary endpoints include (1) procedure and fluoroscopy times, (2) AF burden, (3) proportion of patients with recurrence in the blanking period, (4) proportion of patients undergoing repeat ablation, and (5) quality of life changes at 12 months compared to baseline.

CONCLUSION

COMPARE CRYO will compare the efficacy and safety of the novel PolarX cryoballoon and the standard-of-practice Arctic Front cryoballoon for first PVI performed in patients with symptomatic paroxysmal AF.

TRIAL REGISTRATION

(ClinicalTrials.gov ID: NCT04704986).

Outcomes of pulmonary vein isolation with radiofrequency balloon vs. cryoballoon ablation: a multi-centric study

AIMS

Cryoballoon (CB) ablation is the mainstay of single-shot pulmonary vein isolation (PVI). A radiofrequency balloon (RFB) catheter has recently emerged as an alternative. However, these two technologies have not been compared. This study aims to evaluate the freedom from atrial tachyarrhythmias (ATas) at 1 year: procedural characteristics, efficacy, and safety of the novel RFB compared with CB for PVI in patients with paroxysmal atrial fibrillation (AF).

METHODS AND RESULTS

This prospective multi-centre study included consecutive patients with symptomatic drug-resistant paroxysmal AF who underwent PVI with RFB or CB between July 2021 and January 2022 from three European centres. A total of 375 consecutive patients were included, 125 in the RFB group and 250 in the CB. Both groups had comparable clinical characteristics. At 12.33 ± 4.91 months, ATas-free rates were 83.20% and 82.00% in the RFB and CB groups, respectively (P > 0.05). Compared with the CB group, the RFB group showed a shorter procedure time [59.91 (45.80-77.12) vs. 77.0 (35.13-122.71) min (P < 0.001)], dwell time [19.59 (14.41-30.24) vs. 27.03 (17.11-57.21) min (P = 0.04)], time to isolation, and thermal energy delivery in all pulmonary veins (P < 0.001). First-pass isolation was comparable. No major complications occurred in either group, with no stroke, atrio-oesophageal fistula, or permanent phrenic nerve injury. Transient phrenic nerve palsy occurred more frequently with CB than RFB (7.20% vs. 3.20%; P = 0.02). Oesophageal temperature rise occurred in 21 (16.8%) patients in the RFB group, and gastroscopy showed erythema in two of them with complete recovery after 30 days.

CONCLUSIONS

The RFB appears to have a safety and efficacy profile similar to that of the CB for PVI. Shorter procedural times appear to be driven by shorter left atrial dwell and thermal delivery times.

Utilization of 3D mapping systems in interventional electrophysiology and its impact on procedure time and fluoroscopy-Insights from the "Go for Zero Fluoroscopy" project

AIM

The implementation of 3D mapping systems plays an important role in interventional electrophysiology (EP) in recent years. The aim of the present study was to evaluate use of 3D mapping systems regarding fluoroscopy and procedure duration.

METHOD

In the "Go for Zero Fluoroscopy" project 25 European centers provided data of consecutive EP procedures. Data on use of 3D mapping systems as well as utilization of contact force catheters and multipolar mapping catheters were associated with fluoroscopy time, dose area product (DAP), and procedure duration.

RESULT

A 3D mapping system was used in 966 (54%) cases. Use of 3D mapping for atrioventricular nodal reentry tachycardia (AVNRT) was associated with reduced fluoroscopy time (p < 0.001), DAP (p = 0.04) but increased procedure time (p = 0.029). Moreover, fluoroscopy time (p < 0.001) and DAP (p = 0.005) were significantly lower in the 3D mapping group in ablation of typical atrial flutter. However, the procedure time (p < 0.001) increased. Use of 3D mapping in the ablation of accessory pathway (AP) was associated with reduced fluoroscopy time (p < 0.001) and DAP (p < 0.001) with no significant increase in procedure time (p = 0.066). In the case of atrial fibrillation, a 3D mapping system was used in 485 patients (75.8%). Additional use of a contact force catheter was associated with lower fluoroscopy time (p < 0.001) and DAP (p < 0.001). Use of a multipolar mapping catheter was associated with lower fluoroscopy time (p = 0.002). The implementation of 3D mapping systems in the ablation of ventricular tachycardias resulted in a significant increase in the procedure time (p = 0.001) without significant differences regarding the DAP (p = 0.773) and fluoroscopy time (p = 0.249).

CONCLUSION

Use of 3D mapping systems in ablation of supraventricular tachycardias is associated with lower radiation exposure. Nevertheless, the procedure time often increases, except in the case of ablation for AP. Use of contact force catheters and multipolar mapping catheters is associated with yet lower radiation exposure values. Prospective randomized studies are needed to further elucidate potential benefit of these technological tools.

EUropean real-world outcomes with Pulsed field ablatiOn in patients with symptomatic atRIAl fibrillation: lessons from the multi-centre EU-PORIA registry

AIMS

Pulsed field ablation (PFA) is a new, non-thermal ablation modality for pulmonary vein (PV) isolation in patients with atrial fibrillation (AF). The multi-centre EUropean Real World Outcomes with Pulsed Field AblatiOn in Patients with Symptomatic AtRIAl Fibrillation (EU-PORIA) registry sought to determine the safety, efficacy, and learning curve characteristics for the pentaspline, multi-electrode PFA catheter.

METHODS AND RESULTS

All-comer AF patients from seven high-volume centres were consecutively enrolled. Procedural and follow-up data were collected. Learning curve effects were analysed by operator ablation experience and primary ablation modality. In total, 1233 patients (61% male, mean age 66 ± 11years, 60% paroxysmal AF) were treated by 42 operators. In 169 patients (14%), additional lesions outside the PVs were performed, most commonly at the posterior wall (n = 127). Median procedure and fluoroscopy times were 58 (interquartile range: 40-87) and 14 (9-21) min, respectively, with no differences due to operator experience. Major complications occurred in 21/1233 procedures (1.7%) including pericardial tamponade (14; 1.1%) and transient ischaemic attack or stroke (n = 7; 0.6%), of which one was fatal. Prior cryoballoon users had less complication. At a median follow-up of 365 (323-386) days, the Kaplan-Meier estimate of arrhythmia-free survival was 74% (80% for paroxysmal and 66% for persistent AF). Freedom from arrhythmia was not influenced by operator experience. In 149 (12%) patients, a repeat procedure was performed due to AF recurrence and 418/584 (72%) PVs were durably isolated.

CONCLUSION

The EU-PORIA registry demonstrates a high single-procedure success rate with an excellent safety profile and short procedure times in a real-world, all-comer AF patient population.

Very-early symptomatic recurrence is associated with late recurrence after radiofrequency ablation of atrial fibrillation

AIMS

After radiofrequency catheter ablation (RFCA) of atrial fibrillation (AF), the effect of very-early (within 48 h) symptomatic recurrence (VESR) on late (after 3 months of RFCA) recurrence (LR) has been seldomly reported. We aimed to explore the relationship between VESR and LR among post-RFCA patients.

METHODS AND RESULTS

This was a single-centre prospective cohort study that enrolled 6887 AF patients who received the first RFCA procedure from June 2018 to December 2021 at Beijing Anzhen Hospital. Patients were divided into four groups based on VESR and early (from 48 h to 3 months after RFCA) recurrence (ER): Group A (no VESR, no ER); Group B (VESR but no ER); Group C (ER but no VESR); and Group D (both VESR and ER). Three hundred and thirty (4.79%) patients experienced VESR (Groups B and D). With an average follow-up of 14.7 months after grouping, the Kaplan-Meier curve showed that LR risk in VESR patients was higher than in other patients (log-rank, P < 0.001), and the difference was significant in both paroxysmal (log-rank, P < 0.001) and persistent (log-rank, P < 0.001) AF patients (P for interaction = 0.118). In multivariate analysis, Groups B, C, and D were associated with a 2.161-, 5.409-, and 7.401-fold increase in the risk of LR, respectively. What is more, compared with Group A, VESR-atrial tachycardia and VESR-AF were related to a 3.467- and 5.564-fold LR risk, respectively. In VESR patients, classification based on ER and VESR modes improved the prediction potential of LR risk.

CONCLUSION

Very-early symptomatic recurrence is associated with an increased risk of LR.

Best Practice Guide for Cryoballoon Ablation in Atrial Fibrillation: The Compilation Experience of More than 1000 Procedures

Nowadays, the cryoballoon (CB) constitutes an established alternative to radio frequency (RF) ablation for pulmonary vein isolation (PVI), which offers the possibility to isolate the PVs with a single application. Since the introduction of the second-generation CB, we prospectively collected our data to optimize the procedure on >1000 consecutive patients who underwent CB PVI performed in our center. It is expected that subsequent guidelines will suggest first-line PVI through CB in patients with paroxysmal AF with a class I indication. Indeed, in the long-term follow-up (36 months) of the EARLY-AF trial, CB had a lower incidence of persistent atrial fibrillation episodes compared to the anti-arrhythmic drugs group. We now review the current best practices in an effort to drive consistent outcomes and minimize complications. PV isolation through CB is the most studied single-shot technique for atrial fibrillation ablation, having shown the potential to alter the natural history of the arrhythmia. Several procedural tips and tricks can improve procedural flow and effectiveness. In the present article we provided not only technical details but measurable biophysical parameters that can reliably guide the operator into achieving the best outcome for his patients.

A novel saline-based occlusion tool allows for dye-less cryoballoon-based pulmonary vein isolation and fluoroscopy reduction

Background

Cryoballoon (CB)- based pulmonary vein isolation (PVI) remains guided by fluoroscopy and dye. The novel saline injection-based occlusion tool allows for pulmonary vein (PV)-occlusion assessment without the need for dye injection.

Aim

To compare KODEX-EPD guided CB-PVI using the novel saline injection-based workflow with conventional cryoablation for acute efficacy, fluoroscopy exposure and dye volume.

Methods

Consecutive atrial fibrillation (AF)- patients undergoing CB-PVI in conjunction with KODEX-EPD (Cryo^EPD group) were analyzed. Patients undergoing conventional CB-PVI (Cryo group) in the same time period acted as controls.

Results

One hundred forty patients [91/140 (65%) persistent AF] were studied. Seventy patients underwent Cryo^EPD procedures [64 ± 13 years, 21 (30%) female] and seventy patients underwent Cryo procedures [68 ± 10 years, 27 (39%) female].A total of 560 PVs were identified and successfully isolated. Mean procedure time was 66 ± 15 min for the Cryo^EPD group, and 65 ± 19 min for the Cryo group (p = 0.3). Fluoroscopy time (Cryo^EPD 6 ± 4 min; Cryo 13 ± 6 min, p < 0.001) and dose area product (Cryo^EPD 193 [111; 297] cGycm²; Cryo 381 [268; 614] cGycm², p < 0.001) were lower in patients undergoing Cryo^EPD compared with Cryo procedures. No dye was needed in the Cryo^EPD group while 53 ± 18 ml dye per patient were administered for the Cryo group (p < 0.001). The overall complication rate was comparable between both groups (p = 0.5).

Conclusion

KODEX-EPD guided AF-ablation enables dye-free CB-based PVI with reduced fluoroscopy exposure when compared to conventional CB-ablation, without differences in acute procedural outcomes or procedure duration.