Atrial Fibrillation Ablation Procedures Research Articles

Impact of magnetic data collection prior to electroanatomic model creation on acute outcomes in de novo AF procedures

Abstract Background As ablation and electroanatomical mapping technology evolve, workflows change to maximize the impact on procedural efficacy, safety, and efficiency. In a magnetic-primary navigation mode, optimization of the magnetic-impedance field links (VoXels) must be considered to provide accurate environments for anatomic modeling, mapping, and lesion placement. To achieve this accuracy and optimize speed of data collection, many operators have adopted the strategy of collecting VoXels using an ablation catheter prior to introduction of a multipolar mapping catheter. However, the impact of this workflow on procedural metrics has not yet been quantified in a multicenter, international cohort. Objective Assess the impact of optimizing the magnetic navigation field using an ablation catheter prior to collecting left atrial (LA) data using a high-density diagnostic tool on acute outcomes in de novo atrial fibrillation (AF) ablation procedures. Methods Acute observational data from 199 de novo pulmonary vein isolation (PVI) cases was prospectively collected from 56 operators at 42 centers in Europe, the US, and Australia. Procedural metrics, modeling workflow, ablation technology used, and acute outcomes were collected. Results Of 199 de novo AF (62.3% PAF) ablation procedures, VoXels were collected with an ablation catheter prior to LA map collection with a multipolar catheter in 65/199 (32.7%) cases; the remainder collected with multipolar catheter first. An irrigated, contact force sensing RF ablation catheter was used in all procedures. Mean procedure duration was similar in procedures in which VoXels were collected prior to map collection (VC) compared to those that did not (nVC) (107.0±46.8 min and 115.4±59.2 min, respectively (p=0.28)). Mean fluoroscopy time was significantly reduced in VC cases compared to nVC cases (3.0±4.5 min and 5.3±5.6 min, respectively (p=0.002)). Total RF duration was significantly reduced in VC cases compared to nVC cases (904±444s and 1063±632s, respectively (p=0.04)). There was also a significant reduction in fluid delivered through the ablation catheter in VC cases, 369±159mL, compared to nVC cases, 520±243mL (p<0.001). Acute success rates were similar between groups: 98.5% for VC cases and 99.2% for nVC cases (p=0.64). Conclusion In this international cohort, cases where VoXels were collected prior to map and model collection had significantly reduced fluoroscopy times, RF durations, and fluid volumes delivered through the ablation catheter, potentially as a result of improved model quality. Despite the introduction of an additional step to the workflow, there was a trend toward shorter procedures when VoXels were collected prior to map and model collection, although it did not achieve statistical significance. Better quantification of the impact of this workflow on model quality, along with analysis of long-term patient outcomes, is warranted.Procedure Duration Comparison_VC vs. nVCFluoroscopy Comparison_VC vs. nVC

Left atrial low-voltage areas, but not volume, predict the recurrence of atrial fibrillation in repeat ablation procedures

Abstract Background Left atrial (LA) low voltage areas (LVA) are a controversial target in atrial fibrillation ablation procedures. However, LVA and LA volume are good predictors of arrhythmia recurrence in ablation-naïve patients. Their predictive value in pre-ablated, myopathic atria is uncertain. Purpose Patient selection for repeat ablations is sometimes difficult. Predicting factors of rhythm outcome might help with the decision. Methods Consecutive patients with recurrent atrial fibrillation (AF) or atrial tachycardia (AT) scheduled for repeat LA ablation were included in the prospective Bernau ablation registry between 2016 and 2020. All patients received a complete LA ultra-high-density map before ablation. Maps were analyzed for LA size, LVA percentage and distribution. The predictive value of demographic, anatomic and mapping variables on AF recurrence was analyzed in univariate logistic regression and integrated in a multivariate Cox regression if the p-value was <0.250. Results 160 patients (50.6% male, 1.3 pre-ablations, 60% persistent AF) with complete LA voltage maps were included. Mean follow-up time was 16 ± 11 months. Mean recorded electrograms (EGMs) per map were 9754 ± 5808, mean LA volume was 176.1 ± 35.9 ml and mean rate of LVAs < 0.5 mV was 30.6% ± 23.1%. Baseline characteristics are depicted in table 1. During follow-up recurrence rate of AF or AT > 30 seconds was 55.6%. Patients with recurrence had a significant higher percentage of LVAs (40.0% vs. 18.8%, p<.001) but no relevant difference in LA volume (172 vs. 178 ml, p=.299). ROC curves revealed a cut-off of 22% LVAs with highest sensitivity (73.0%) and specificity (71.8%). Based on this cut-off event free survival was significantly higher in the Low LVA group (p<0.01), Figure 1. Other relevant clinical, anatomic or laboratory predictors could not be found in multivariate Cox regression analysis. Conclusion The amount of left atrial LVA is a good predictor for arrhythmia recurrence, even in a cohort of repeat ablations with progressively diseased atria. EAM derived left atrial volume has minor impact on recurrence in this group and should not solely guide the decision in favor or against further invasive treatment. Accomplishing a thorough 3D map of the left atrium to account for LVA should be mandatory in all repeat procedures.Baseline CharacteristicsKaplan-Meier for recurrence and voltage

Procedural and outcome impact of body mass index on pulsed field ablation of atrial fibrillation: insights from the EU-PORIA Registry

Abstract Introduction Pulsed field ablation (PFA) is a "single-shot" non thermal ablation modality for atrial fibrillation (AF). In general, obesity is associated with increased risk of AF recurrence after catheter ablation with thermal energy sources. Purpose We aimed to assess the impact of body mass index (BMI) on procedural characteristics, safety, acute efficacy and long-term outcomes of PFA for symptomatic AF. Methods Of 1233 subjects enrolled in the EU-PORIA registry, in our subanalysis we included 1055 patients undergoing de novo pulmonary vein isolation (PVI)-only ablation procedure for symptomatic AF using the pentaspline PFA catheter from March 2021 until May 2022 at seven high-volume European centers. Patients were divided into two groups based on BMI: normal weight (nW, < 25 kg/m2) and overweight (oW, ≥ 25 kg/m2). Overweight patients were further categorized into three subgroups: pre-obesity (pOb, 25-29.9 kg/m2), obesity (Ob, 30-34.9 kg/m2) and severe obesity (sOb, ≥ 35 kg/m2). Clinical and procedural characteristics, complications and follow up data were collected. Results A total of 1055 patients (39% female, mean age 65,7±10,9 years, 65% paroxysmal AF) were enrolled. 32% of patients were normal weight (nW) and 68% overweight (oW). Among oW group, 438 subjects (41%) were assigned to pOb group, 204 (19%) to Ob, and 71 (7%) to sOb. Acute PVI was achieved in 100% of cases. The median skin-to-skin procedure and the median fluoroscopy time were similar between nW and oW and in all investigational subgroups, but radiation exposure increased in line with BMI (p<0.001). Periprocedural complications were 5% in nW, 1.6% in pOb, 3.9% in Ob, and 2.8% in sOb (p=0.06). The Kaplan-Meier estimate of arrhythmia-free survival was 80.2% in nW and 71.9% in oW (p=0.017). Each unit increment in BMI was associated with 4.2% increase in risk of AF/AT recurrence. Severe obese patients presented the highest 1-year AT/AF recurrence rate (37.2%). In the sOb group the rate of recurrence was not influenced by the type of AF (PAF 65.7% vs. pers AF 59.4%; p=0.484). Conclusion Overweight patients seem to experience more AF recurrences even after PFA PVI, mainly driven by a higher recurrence rate for BMI ≥ 35 kg/m2. Weight reduction programs remain crucial, nevertheless, reduced procedural times, good safety profile and acceptable 1-year observed AF/AT freedom make PFA a feasible strategy for AF rhythm control in patients with BMI ≥ 25 kg/m2.Freedom from AF/AT recurrence

Pulsed-field ablation using a lattice-tip catheter without general anesthesia is feasible for atrial fibrillation ablation

Abstract Background General anesthesia (GA) was employed to titrate lesion formations for a pulsed-field ablation (PFA) using a lattice-tip catheter. The evidence using a lattice-tip catheter without the use of GA is limited. Purpose We conducted a series of exploratory evaluation of a lattice-tip PFA catheter ablation without GA. Methods Patients undergoing their first atrial fibrillation (AF) ablation procedures using a lattice-tip catheter were enrolled in the study. To assess acute outcomes and safety, the patients were divided into two groups: one undergoing the procedure with GA and the other without GA. Procedural characteristics were collected. Results In total, 20 patients (6 with GA, 14 without GA) were enrolled in the current study. One patient in non-GA group needed a larynx mask due to apnea from anesthesia. The pre-ablation 3D mapping time was equivalent between the two group (with GA versus without GA: 17±7 versus 16±5; P=0.762). All first-pass isolations of the pulmonary veins (PV) were successfully achieved, and there was no difference in the number of applications between the right and left PV (with GA versus without GA: 45±8 versus 53±12; P=0.206 and 47±14 versus 49±9; P=0.792). Linear lesions including anterior linear ablation (33% with GA and 36% without GA: P=1.000), roof linear ablation (67% with GA and 71% without GA: P=1.000) and cavo-tricuspid isthmus ablation (0% with GA and 7% without GA: P=1.000) were performed. The ablation, laboratory stay and fluoroscopy times were equivalent between the two group (with GA versus without GA:88±22 versus 97±20; P=0.483, 128±25 versus 111±18; P=0.216 and 9±4 versus 10±2; P=0.902), while the pre-ablation preparation times were shorter in the group without GA (with GA versus without GA:40±17 versus 14±4; P<0.01). There was no major and minor procedural complication in both groups. Conclusions The use of a lattice-tip catheter for ablation without GA has a potential to shorten the whole procedural work-flow including preparing time while maintaining comparable safety and lesion formation to cases where GA is utilized.

A straightforward assessment of anterior mitral isthmus lines block

Abstract Background Complex atrial fibrillation (AF) and left atrial flutter (LAFL) ablation procedures often involve creating lines on the anterior wall of the left atrium, such as the anterior septal and lateral mitral isthmus lines. Purpose This study aims to evaluate the role of a simplified criteria to demonstrate the achievement of conduction block across the anterior wall of the left atrium ("anterior mitral isthmus") after linear ablation (LA). Methods Patients scheduled for persistent AF or LAFT ablation were prospectively recruited. The procedure employed a homogeneous LA strategy that included the anteromedial, anterolateral and roof lines. The following intervals were measured before and after LA, placing a multipolar catheter in the left atrial appendage (LAA) in order to register the earliest egm in a reproducible position: 1) P-LAA: conduction time from the sinus P wave onset to the LAA, 2) IASp-LAA: conduction time pacing at CL 500 ms from the interatrial septum to the LAA, 3) CSp-LAA: conduction time pacing at CL 500 ms from the distal CS to the LAA, 4) LAA-QRS onset. Patients with linear ablation were further divided according to the presence or block (BG) or non-block group (NBG) in the anterior at the end of the procedure, demonstrated with a high-density activation map. A parallel control group (CG) of patients with paroxysmal AF without LA was also included for comparison. Statistical analysis involved the Kruskal-Wallis and Mann-Whitney test with Bonferroni correction. Results 21 patients were enrolled in the study: mean age 66.67 years (± 8.48), 80% male sex. Among them, 16 had AF and AFL and underwent LA, while the remaining 5 constitute the CG. Baseline measures before LA did not exhibit significant differences compared to the CG with mean values for P-LAA at 93±20 ms (P=2.35), IASs-LAA at 82±27 ms (P=1.94), CSs-LAA at 52±17 ms (P=0.91), and LAA-QRS at 80±27 ms (P=1.82). However, upon comparing the BG and NBG, significant differences emerged in P-LAA (82±10 ms vs. 11±5 ms (P=0.002) and IAS-LAA (83±17 ms vs. 27±24 ms (P=0.004), while no significant differences were observed in the remaining intervals. In comparisons between the BG and the CG, significant differences were noted in P-LAA (82±10 ms vs. 16±10 ms (P=0.01) and IAS-LAA (83±17 ms vs. 1.2±17 ms (P=0.01), without differences in the other intervals. Conversely, when comparing NB to the CG, no significant differences were observed in any of the intervals. Finally, P-LAA >70 ms and the IASp-LAA >55 ms showed a sensitivity of 100 % and specifitity of 100 vs. 87% respectively to discriminate anterior wall block. Conclusion The simple measurement of the P-LAA and IAS-LAA interval proves highly valuable in evaluating anterior mitral isthmus lines block, serving as a complementary approach to conventional maneuvers. P-LAA >70 ms and IASp-LAA > 55 ms could be usefull to discriminate anterior wall block.Anterior linear ablation with block

Endoscopic versus surgical treatment for the management of oesophageal fistula after atrial fibrillation ablation - a subanalysis of the worldwide POTTER-AF study

Abstract Background Oesophageal fistula (OF) is considered the most dreadful complication of atrial fibrillation (AF) catheter ablation. The endoscopic and surgical treatment of OF has been proposed to improve the prognosis of these patients, but the data on the individual impact of each treatment technique are scarce. Methods The POTTER-AF study is a worldwide, multi-centre registry conducted under the auspices of the Working Group of Cardiac Electrophysiology of the German Cardiac Society (AGEP, DGK) which evaluated the incidence, management, and outcome of post-procedural OF following catheter ablation of AF [1]. A total of 553 729 patients underwent ablation procedures for AF or atrial tachycardia (AT) in 214 electrophysiological centres from 35 countries between 1996 and 2022. Of them, 138 (0.025%) patients experienced postprocedural OF and data regarding the therapeutical approach were available in 116 patients. Of them, 78 underwent surgical or interventional treatment. Herein we conducted a therapy- based analysis of the patients exhibiting OF. Purpose To assess the impact of each therapeutical approach on the prognosis of patients developing OF after AF or AT ablation. Results A total of 23 (29.5%) patients were treated using endoscopic interventions only (Endoscopy group), while 55 (70.5%) patients underwent surgical procedures (Surgery group). Of the latter, 8 (14.5%) underwent previous endoscopic treatment. The endoscopic therapy consisted of oesophageal stenting (n = 28), clipping (n = 2), or vacuum-assisted-closure therapy (n = 1). There was no difference between the Endoscopy and Surgery groups regarding the demographic characteristics and comorbidities. The energy sources used were also similar between the groups (Figure 1). There was a trend towards a higher use of an oesophageal thermal probe in the Endoscopy group (43.5% vs. 21.8%; p=0.096). The duration until symptoms onset was 10 (5.5; 18.5) days in the Endoscopy group and 18.0 (10.0; 22.0) days in the Surgery group (p=0.081), while the time to OF diagnosis was 18.0 (10.0; 26.0) days and 20.0 (15.0; 29.25) days respectively (p=0.10; Figure 2). The symptoms at presentation were similar between the two groups. Endoscopy was the diagnostic method in 45.5% of the patients in the Endoscopy group and in 16.7% in the Surgery group (p=0.017). The subsequent complications of the OF were also similar between groups. The mortality was 56.5% in the Endoscopy group and 51.9% in the Surgery group (p=0.805), while minor sequalae occurred in 8.7% patients in the former group and 16.7% in the latter (p=0.490) and major sequalae in 4.3% and 16.7% respectively (p=0.266). Conclusion There was no clinical or paraclinical parameter associated with the choice of the therapeutical approach. Patients diagnosed by means of endoscopy were more likely to undergo exclusively endoscopic interventions. The mortality, incidence of minor and major sequalae were similar between the groups.

Impact of gender on the management and prognosis of oesophageal fistula after atrial fibrillation ablation - a subanalysis of the worldwide POTTER-AF study

Abstract Background Oesophageal fistula (OF) is a rare but devastating complication following atrial fibrillation (AF) ablation. The data regarding the impact of gender on the management and prognosis of OF are scarce. Methods The POTTER-AF study is a worldwide, multi-centre registry conducted under the auspices of the Working Group of Cardiac Electrophysiology of the German Cardiac Society (AGEP, DGK) which evaluated the incidence, management, and outcome of post-procedural OF following catheter ablation of AF. A total of 553 729 patients underwent ablation procedures for AF or atrial tachycardia (AT) in 214 electrophysiological centres from 35 countries between 1996 and 2022. Of them, 138 (0.025%) patients experienced postprocedural OF and data regarding the gender, management and prognosis were available in 117 patients. Herein we conducted a gender- based analysis of the patients exhibiting OF. Purpose To evaluate the impact of gender on the management and prognosis of OF. Results Females represented 47% of the study population, which is a notable finding considering that the female population represents only a minority of the patients receiving AF/AT ablation. They were less likely to have atrioesophageal fistula (90.9% vs. 100%; p=0.021). Oesophageal-pericardial fistula occurred solely in females (7.3% vs. 0%; p=0.046). Congestive heart failure was significantly less frequent in the female population (7.4% vs. 26.7%; p=0.012). No other difference was seen between genders regarding the baseline characteristics and comorbidities (Table1). The energy source, ablation technique and utilization of oesophageal temperature probes were similar for males and females. Significantly less women received proton pump inhibitors (PPI) postprocedural (64.8% vs. 84.7%; p=0.017). The median duration until onset of symptoms was 20 days for women and 16.5 days for men (p=0.14), while the median duration until OF diagnosis was 22.5 days and 19.5 days respectively (p=0.217). Significantly more women underwent echocardiography (36.4% vs. 15%; p=0.01) as diagnostic method. More women exhibited stroke (32.7% vs. 14.8%; p=0.040), while there was no significant difference regarding the incidence of septic shock, coma, cardiac arrest, cardiac tamponade, and gastro-intestinal bleeding. Significantly more women than men presented no complications other than OF (9.6% vs. 0%; p=0.026). The females were more likely to undergo endoscopic treatment (35.8% vs. 17.7%; p=0.034), but less likely to undergo direct surgical treatment, without stenting (28.3% vs. 51.6%; p=0.014) (Figure1). The mortality was 63.6% for women and 67.2% for men (p=0.70), with no difference in terms of major and minor sequelae. Conclusion Approximatively half of the patients exhibiting postprocedural OF are females. Women showed a higher rate of endoscopic treatment and a lower rate of direct surgical treatment. The survival, as well as the incidence of minor and major sequelae were similar between genders.

Feasibility and efficacy of single-shot PFA technology for redo procedures after a previous atrial fibrillation ablation procedure

Abstract Introduction Despite significant technological advancements and a better understanding of atrial tachyarrhythmia pathophysiology, a non-negligible percentage of atrial fibrillation (AF) patients undergoing catheter ablation experiences arrhythmia relapse. Repeat procedures have been traditionally performed via thermal energy systems, which carry a certain risk of collateral damage to adjacent tissues. Pulsed Field Ablation (PFA) has emerged as an alternative non-thermal energy source for cardiac ablation. The main advantage is its selectivity to cardiac tissue. FarapulseTM is the first PFA technology to have received regulatory approval and includes a pentaspline PFA catheter. Although designed for pulmonary vein isolation, its use for extrapulmonary vein site ablation has been previously documented. Purpose To evaluate the feasibility and efficacy of the pentaspline FarawaveTM for redo procedures. Methods Patients referred for a redo procedure using FarapulseTM system were enrolled in 3 high-volume European centers. A workflow (Figure 1.A) was established based on rhythm at presentation (Group 1: sinus rhythm; Group 2: AFL; Group 3: AF). Results A total of 117 patients were included (64 in Group 1, 18 in Group 2, and 35 in Group 3). The mean number of previous procedures was 1.26, and 23 patients (19.66%) had already undergone ≥2 procedures. Previous ablation targets included PVI, either alone (46.15%) or in combination with other targets, including posterior mitral line (39.32%), posterior wall (6.84%), or anterior mitral line (2.56%). Electroanatomical mapping (EAM) was adopted in 15.38% of the cases. Specifically, in 27.78% (n=5) of group 2, 15.63% (n=10) of group 1 and 8.57% (n= 3) of group 3 cases. Additional focal radiofrequency ablation was required in 4 patients for CTI line ablation. Lesion sets are depicted in Figure 2. Mean procedural and LA dwelling time were 95.2 ± 38.0 and 50.7 ± 36.7 minutes, respectively. There was a total of one major complication (intracranial haemorrhage) and 5 minor complications (two vascular site related, and three reversible ST segment changes, related to applications on the mitral annulus area). A total of 100 patients completed at least 3 months of follow-up (FU), with a median FU time was 7.55 months (IQR 5.18 – 11.85). The total number of recurrences was 20, including 2 during the blanking period. Survival function (excluding blanking period) was 88.6 (95% CI 79.7 – 93.8) at 6 months and 80.0% (95% CI 67.3 – 88.3) 12 months. Atrial arrhythmia free-survival was higher in patients presenting in sinus rhythm, compared to the other two groups (p = 0.0135), as displayed in Figure 1.B. Conclusion The proposed stepwise approach to repeat AF ablation procedures based on the use of the single-shot PFA system (with or without EAM) was feasible, safe, fast and effective at one year follow-up.Flow chart and Kaplan Meier curveLesion sets

Impact of early recurrences on late recurrences after pulmonary vein isolation with pulsed field ablation. A subanalysis from the EU-PORIA multicenter international registry

Abstract Background Early recurrences of atrial tachyarrhythmia (ERAT) are commonly observed after pulmonary vein isolation (PVI) with thermal energies. ERAT during the 90-day blanking period (BP) should not be considered therapy failure as the cardiac tissue is still healing and the long-term benefit of PVI may not be immediately apparent. With the introduction of pulsed field ablation (PFA), a non thermal, myocardial-specific ablation technology for atrial fibrillation (AF), the significance of ERAT following PVI is unclear. Methods EU-PORIA (EUropean real-world outcomes with Pulsed field ablatiOn in patients with symptomatic atRIAl fibrillation), a multicentre international registry, collected data from 1233 patients treated with the pentaspline PFA catheter. For the current analysis, patients with a previous AF ablation procedure, patients treated with lesions beyond PVI, and patients without complete follow up data (during and following the BP) were excluded. The rate and significance of ERAT following PFA PVI were analysed. Results This subanalysis included 1011 patients (38% female, 66±11 years old, 64% paroxysmal atrial fibrillation [PAF]). ERATs were recorded in 178/1011 (18%) of patients (16% in PAF and 21% in persAF, p=0,021). Notably, ERAT patients were older (67,1±11,4 Vs 65,4±10,9, p=0,015) and had a higher median CHA2DS2-VASc Score (2,5 [IQR:1-4] Vs 2 [IQR:1-3]; p=0,019). The 35-mm catheter was more often used in ERAT patients (48/178(27%) Vs 148/833(18%) – p=0,005). At a median follow-up of 365 days (IQR 347-390), 100/178(56%) of patients with ERAT had documented late recurrence (LR), compared to only 147/833(18%) of patients in sinus rhythm throughout BP (p<0,001). Kaplan Meier estimates for overall freedom from AF/AT outside of the BP was 77% at one year for all patients. Patients with ERAT had a significantly lower freedom from AF/AT compared to patients with no ERAT (42% vs 84%, log-rank p<0,001). The absence of ERAT was associated with long-term success independent of the type of AF (41% Vs 88% in PAF, 43% vs 74% in persistent AF; p<0,001 for both). Among ERAT patients, no additional predictors for LR were identified. Conclusions In this large multicentre international registry, early recurrence of atrial tachyarrhythmia following PFA PVI were recorded in 18% of patients. ERAT was associated with late recurrences in the majority of cases, independent of AF type. The need for a blanking period following non thermal energy ablation for atrial fibrillation should be further questioned.

Integrating clinical variables with magnetic resonance imaging and electroanatomic mapping parameters to predict response to first-time and repeat atrial fibrillation ablation procedures

Abstract Background The heterogeneity in patient response to atrial fibrillation ablation mandates the development of methods to predict clinical outcomes. Several clinical risk scores exist to prognosticate patients post ablation. Magnetic resonance imaging can quantify anatomical and functional atrial properties, whilst electroanatomic mapping data provides unparalleled atrial substrate characterisation. These data could be leveraged to predict ablation outcomes more accurately. Purpose To incorporate magnetic resonance imaging and electroanatomic mapping parameters with clinical variables to predict response to 1) first-time and 2) repeat atrial fibrillation ablation. Methods A retrospective analysis of 123 consecutive patients undergoing first-time atrial fibrillation ablation including pre-procedural atrial magnetic resonance imaging was performed. Data were split into training (n=68) and test (n=55) cohorts depending on data availability for clinical risk score calculation. The APPLE, DR-FLASH, FLAME, HATCH, HATCH+OSA, CHA2Ds2VASc and CAAP-AF scores were calculated for patients in the training cohort. Univariate logistic regression was used to identify variables associated with arrhythmia recurrence which were then combined into a multivariate logistic regression model. Area under the curve receiver operating characteristic (AUC-ROC) analysis was used to compare the ability of clinical risk scores and the combined model to predict arrhythmia recurrence risk after one procedure. The model's ability to predict repeat ablation response was tested in 38 patients who underwent redo procedures. The ROC optimal cut-off score was used to divide patients into two groups (high and low arrhythmia recurrence risk) for time-to-event analysis. Results In univariate analysis, weight, age, hypertension, left atrial ejection fraction and mean left atrial bipolar voltage were associated with arrhythmia recurrence after one procedure. The multivariate logistic regression model achieved an AUC of 0.7491 (95% confidence interval (CI) 0.6269-0.8712) in the training cohort and 0.7457 (95% CI 0.6137-0.8778) in the test cohort for predicting arrhythmia recurrence at 12 months (Figure 1A). Amongst clinical risk prediction tools, CAAP-AF had the highest predictive value (AUC 0.6529, 95% CI 0.5265-0.7793) (Figure 1B). In patients undergoing repeat ablations, the combined model had an AUC of 0.7585 (95% CI 0.5989-0.9182) for predicting arrhythmia recurrence (Figure 2A). The Kaplan-Meier curves showed a higher risk of arrhythmia recurrence in the ‘high recurrence risk’ group at 12 months (log-rank p=0.029) (Figure 2B). Conclusion A logistic regression model integrating clinical, anatomical, functional, and electrophysiological parameters improved the accuracy of atrial fibrillation ablation outcome prediction compared to existing clinical risk scores. The model may be used to predict response to repeat procedures offering the potential to improve the patient selection process.

Multicenter retrospective evaluation of a patient-tailored electrogram-based ablation strategy using an artificial intelligence software in repeat atrial fibrillation ablation procedures

Abstract Background While pulmonary vein isolation (PVI) is the gold standard approach of treatment of atrial fibrillation (AF), the optimal strategy in case of AF recurrences for redo patients is not well established. Several studies described the usefulness of ablating in atrial regions exhibiting abnormal electrograms, i.e. spatio-temporal dispersion, during AF and an artificial intelligence (AI) electrograms (EGMs)-based software solution has been developed and validated to obtain real-time adjudications of multipolar electrograms in de novo patients. Purpose This study sought to evaluate the novel AI-EGMs-based software approach for redo-AF ablation procedures. Methods This study was a retrospective, multicentric, nonrandomized study. Patients with recurrent symptomatic AF were enrolled in 7 European centers. Redo ablation procedures were performed using the AI software and acute and long-term outcomes after ablation were evaluated. Results A total of 117 patients with refractory symptomatic AF admitted for redo procedure were included with 30% paroxysmal, 42% short-standing persistent and 28% long-standing persistent AF at the time of the redo procedure. During the index procedures, a previous PVI ablation was performed in all patients while additional ablation such as lines and EGM-based ablation was performed in 64 patients (55%). Out of 117 patients, 30 (26%) presented with structural heart disease, 61 (52%) with hypertension, 31 (26%) with a BMI >30, 16 (14%) a sleep apnea syndrome and 24 (20%) had an antiarrhythmic treatment at the time of the procedure. The average AF history was 6.54 ± 4.15 years with an average sustained duration equal to 25 ± 62 months. AI-EGMs-based AF ablation was performed in all patients and easily integrated in the physicians’ workflow during redo procedures. AF termination, i.e. AF regularization or sinus rhythm conversion, occurred in 82/117 patients (71%) with sinus rhythm conversion by ablation in 79/117 patients (68%). After a mean follow-up of 11 ± 5 months, 81% of patients were free from documented AF, with or without antiarrhythmic drugs (AADs) after one redo procedure and 60% of patients were free from any documented atrial arrhythmia, with or without AADs, after one redo procedure per patient. Furthermore, we observed that 77%, 84% and 82% of patients were free from documented AF with or without AADs in paroxysmal, short-standing and long-standing persistent AF patients respectively, and that 71%, 59% and 49% of patients were free from any documented atrial arrhythmia with or without AADs in paroxysmal, short-standing and long-standing persistent AF patients respectively. Conclusions This retrospective study reports that patient-tailored spatiotemporal dispersion ablation is a relevant and standardized approach for repeat AF ablation. This was obtained with an AI-EGMs-based software solution, which may be added to the operative workflow of redo AF procedures.

Atrio-oesofageale fistels na ablatie bij voorkamerfibrillatie: diagnose en aanpak voor de eerste lijn

How to diagnose and manage atrio-esophageal fistulas occurring after atrial fibrillation ablation procedures? An atrio-esophageal fistula (AEF) is a rare complication occurring after an ablation procedure for atrial fibrillation, associated with a high mortality. The aim of this study is to provide a practical flowchart for first-line healthcare professionals on the diagnostics and management of these patients. A literature search was performed, resulting in the inclusion of 100 AEF cases after atrial fibrillation ablation procedures (85 reports). The documentation on these 100 patients was analyzed to compose the flowchart. All patients presented within 2 months after the ablation procedure (23 ± 11 days). Neurologic symptoms (75%), fever (73%) and both symptoms (57%) occurred in the majority. A CT scan of the chest was performed in 78% of the cases. In 30% of the patients, an AEF was observed. In other patients, the diagnosis was suspected based on air in the left cardiac circulation or the mediastinum. An esophagogastroscopy resulted in an infaust deterioration in 14/26 of the cases. In total, 41 patients received esophageal surgery (76% survival) versus 9 with only stenting (22% survival). In 27 patients, the diagnosis or treatment was not obtained in time. An AEF should be suspected in patients presenting with fever or neurological symptoms after a recent ablation procedure. CT scans of the chest and head can support the diagnosis. Once diagnosed, one should proceed to emergency surgery to prevent further complications. An esophagogastroscopy should be avoided. The authors hope to provide a practical management guide, allowing an earlier diagnosis, a faster treatment and thus an improved survival in these patients.

Pre- and post-procedural cardiac imaging (computed tomography and magnetic resonance imaging) in electrophysiology: a clinical consensus statement of the European Heart Rhythm Association and European Association of Cardiovascular Imaging of the European Society of Cardiology.

Imaging using cardiac computed tomography (CT) or magnetic resonance (MR) imaging has become an important option for anatomic and substrate delineation in complex atrial fibrillation (AF) and ventricular tachycardia (VT) ablation procedures. Computed tomography more common than MR has been used to detect procedure-associated complications such as oesophageal, cerebral, and vascular injury. This clinical consensus statement summarizes the current knowledge of CT and MR to facilitate electrophysiological procedures, the current value of real-time integration of imaging-derived anatomy, and substrate information during the procedure and the current role of CT and MR in diagnosing relevant procedure-related complications. Practical advice on potential advantages of one imaging modality over the other is discussed for patients with implanted cardiac rhythm devices as well as for planning, intraprocedural integration, and post-interventional management in AF and VT ablation patients. Establishing a team of electrophysiologists and cardiac imaging specialists working on specific details of imaging for complex ablation procedures is key. Cardiac magnetic resonance (CMR) can safely be performed in most patients with implanted active cardiac devices. Standard procedures for pre- and post-scanning management of the device and potential CMR-associated device malfunctions need to be in place. In VT patients, imaging-specifically MR-may help to determine scar location and mural distribution in patients with ischaemic and non-ischaemic cardiomyopathy beyond evaluating the underlying structural heart disease. Future directions in imaging may include the ability to register multiple imaging modalities and novel high-resolution modalities, but also refinements of imaging-guided ablation strategies are expected.

Symptoms of gastroesophageal reflux disease predicts low voltage zones in the posteroinferior left atrium in patients with persistent atrial fibrillation

BackgroundThe presence of low voltage zones (LVZs) in the left atrium (LA) is associated with the recurrence of atrial fibrillation (AF) following pulmonary vein isolation. Numerous studies have posited a link between gastroesophageal reflux disease (GERD) and AF, attributing this relationship to the anatomical proximity of the esophagus to the posteroinferior wall of the LA. ObjectiveThe objective of this study was to investigate if GERD can predict the presence of LVZs in the posteroinferior wall of the LA. MethodsFive hundred and fifty-one patients with persistent AF, scheduled for their first AF ablation procedure, were prospectively enrolled. Voltage maps were collected using a multipolar catheter, and LVZs were defined as areas measuring ≥3 cm2 with a peak-to-peak bipolar voltage of <0.5 mV. Information on GERD symptoms was gathered from the participants through a self-administered questionnaire. ResultsLongstanding persistent AF was present in 22.3% of the total cohort. GERD was present in 29% of the patients and LVZs in the posteroinferior wall in 12.7%. In the multivariable analysis, patients with GERD were found to have more than twice the odds (Odds Ratio: 2.26, 95% Confidence Interval: 1.24-4.13, P=0.008) of exhibiting LVZs in the posteroinferior wall of the LA compared to patients without GERD. GERD was not associated with LVZs in any other region of the LA. ConclusionGERD was found to be independently associated with LVZs in the posteroinferior LA. This association may be attributable to inflammation and may partly explain the link between GERD and AF.

Left atrial low-voltage areas, but not volume, predict the recurrence of atrial fibrillation in repeat ablation procedures.

Left atrial (LA) low voltage areas (LVA) are a controversial target in atrial fibrillation ablation procedures. However, LVA and LA volume are good predictors of arrhythmia recurrence in ablation-naïve patients. Their predictive value in progressively diseased pre-ablated atria is uncertain. Consecutive patients with recurrent atrial fibrillation (AF) or atrial tachycardia (AT), who were scheduled for repeat LA ablation, were enrolled in the prospective Bernau ablation registry between 2016 and 2020. All patients received a complete LA ultrahigh-density map before ablation. Maps were analyzed for LA size, LVA percentage and distribution. The predictive value of demographic, anatomic, and mapping variables on AF recurrence was analyzed. 160 patients (50.6% male, 1.3 pre-ablations, 60% persistent AF) with complete LA voltage maps were included. Mean follow-up time was 16 ± 11 months. Mean recorded electrograms (EGMs) per map were 9754 ± 5808, mean LA volume was 176.1 ± 35.9 ml and mean rate of LVAs <0.5 mV was 30.6% ± 23.1%. During follow-up recurrence rate of AF or AT>30 s was 55.6%. Patients with recurrence had a significant higher percentage of LVAs (40.0% vs. 18.8%, p < .001) but no relevant difference in LA volume (172 vs. 178 mL, p = .299). ROC curves revealed LVA as a good predictor for recurrence (AUC = 0.79, p < .001) and a cut-off of 22% LVAs with highest sensitivity (73.0%) and specificity (71.8%). Based on this cut off, event free survival was significantly higher in the Low LVA group (p < .01). Total LVA percentage has a good predictive power on arrhythmia recurrence in a cohort of advanced scarred left atria in repeat procedures independent of the applied ablation strategy. Left atrial volume seems to have minor impact on the rhythm outcome in our study cohort.

Efficacy of Computed Tomography-Based Evaluation of Myocardial Extracellular Volume Combined With Red Flags for Early Screening of Concealed Cardiac Amyloidosis in Patients With Atrial Fibrillation.

The prevalence of transthyretin amyloid cardiomyopathy (ATTR-CM) in atrial fibrillation (AF) patients remains unclear. We explored the efficacy of computed tomography-based myocardial extracellular volume (CT-ECV) combined with red flags for the early screening of concealed ATTR-CM in AF patients undergoing catheter ablation.Methods and Results: Patients referred for AF ablation at Oita University Hospital were prescreened using the red-flag signs defined by echocardiographic or electrocardiographic findings, medical history, symptoms, and blood biochemical findings. Myocardial CT-ECV was quantified in red flag-positive patients using routine pre-AF ablation planning cardiac CT with the addition of delayed-phase cardiac CT scans. Patients with high (>35%) ECV were evaluated using technetium pyrophosphate (99 mTc-PYP) scintigraphy. A cardiac biopsy was performed during the planned AF ablation procedure if 99 mTc-PYP scintigraphy was positive. Between June 2022 and June 2023, 342 patients were referred for AF ablation. Sixty-seven (19.6%) patients had at least one of the red-flag signs. Myocardial CT-ECV was evaluated in 57 patients because of contraindications to contrast media, revealing that 16 patients had high CT-ECV. Of these, 6 patients showed a positive 99 mTc-PYP study, and 6 patients were subsequently diagnosed with wild-type ATTR-CM via cardiac biopsy and genetic testing. CT-ECV combined with red flags could contribute to the systematic early screening of concealed ATTR-CM in AF patients undergoing catheter ablation.

Utility and Validity of the HFA-PEFF andH2FPEF Scores in Patients With Symptomatic Atrial Fibrillation.

Diagnosis of heart failure with preserved ejection fraction (HFpEF) in patients with atrial fibrillation (AF) represents a significant clinical challenge. Two diagnostic scoring tools have been developed to aid the noninvasive diagnosis of HFpEF: the HFA-PEFF (Heart Failure Association Pre-test assessment, Echocardiography and natriuretic peptide, Functional testing, Final etiology) and the H2FPEF scoring systems. The purpose of this study was to evaluate the performance of these 2 scoring tools for the diagnosis of HFpEF against a gold standard of invasive evaluation in a cohort of patients with AF. The authors recruited consecutive patients with symptomatic AF and preserved ejection fraction who were scheduled for an AF ablation procedure. Gold-standard invasive diagnosis of HFpEF was performed at the AF ablation procedure using mean left atrial pressure at rest and following infusion of 500mL fluid. Each participant was scored according to the noninvasive HFA-PEFF and H2FPEF scoring systems. Sensitivity and specificity analyses were performed to assess the accuracy of these scoring systems in diagnosing HFpEF. In total, 120 participants were recruited. HFpEF was diagnosed invasively in 88 (73.3%) participants, whereas 32 (26.7%) had no HFpEF. Using the HFA-PEFF score, 38 (31.7%) participants had a high probability of HFpEF and 82(68.3%) had low/intermediate probability of HFpEF. Using the H2FPEF tool, 72 (60%) participants had a high probability of HFpEF and 48 (40%) had intermediate probability. A high HFA-PEFF (≥5 points) score could diagnose HFpEF with a sensitivity of 40% and a specificity of 91%, and a high H2FPEF score (≥6 points) could diagnose HFpEFwith a sensitivity of 69% and specificity of 66%. Overall diagnostic accuracy was similar using both tools (AUC:0.663 vs 0.707, respectively; P = 0.636). Against a gold standard of invasively diagnosed HFpEF, the HFA-PEFF and H2FPEF scores demonstrate only moderate accuracy in patients with AF and should be utilized with caution in this cohort of patients. (Characterising Left Atrial Function and Compliance in Atrial Fibrillation; ACTRN12620000639921).

The outcomes of concomitant catheter ablation in non-mitral valve cardiac surgery-a systematic review and meta-analysis of the literature.

Atrial fibrillation (AF) is the most common form of cardiac arrythmia, with a key importance in the perioperative setting of cardiac surgery. In recent years, the question as to whether pre-existent AF should be treated concomitantly when undergoing cardiac surgery has been heatedly debated. This systematic review and meta-analysis sought to delineate the outcomes of patients undergoing concomitant AF ablation procedures alongside cardiac surgery. The methods for this systematic review and meta-analysis adhered to the Preferred Reporting Items for Systematic Reviews and Meta-analyses statement. Four databases were searched, ultimately yielding 22 papers for inclusion, using appropriate search terminology. Meta-analysis using proportions or means, as appropriate, were applied. Kaplan-Meier curves were digitized and aggregated using previously reported and validated techniques. A total of 9,428 patients (67% male) were identified across the study period as having received non-mitral cardiac surgery and concomitant AF ablation procedures. On actuarial assessment, freedom from AF was found to be 93%, 88%, 85%, 82%, and 79% at 1 through to 5 years, respectively. Freedom from mortality was found to be 94%, 93%, 91%, 90%, and 87% at 1 through to 5 years, respectively. This review demonstrated excellent freedom from AF out to a long-term follow-up of 5 years. Freedom from mortality was also encouraging. Emerging data are increasingly illustrating that in this patient cohort, concurrent treatment of pre-existent AF with cardiac and/or valvular disease at the point of operation should be the standard of care. Robust data in the form of randomized control trials will hopefully solidify this assertion.

Robust, high-density lesion mapping in the left atrium with near-infrared spectroscopy.

Radiofrequency ablation (RFA) procedures for atrial fibrillation frequently fail to prevent recurrence, partially due to limitations in assessing extent of ablation. Optical spectroscopy shows promise in assessing RFA lesion formation but has not been validated in conditions resembling those in vivo. Catheter-based near-infrared spectroscopy (NIRS) was applied to porcine hearts to demonstrate that spectrally derived optical indices remain accurate in blood and at oblique incidence angles. Porcine left atria were ablated and mapped using a custom-fabricated NIRS catheter. Each atrium was mapped first in phosphate-buffered saline (PBS) then in porcine blood. NIRS measurements showed little angle dependence up to 60deg. A trained random forest model predicted lesions with a sensitivity of 81.7%, a specificity of 86.1%, and a receiver operating characteristic curve area of 0.921. Predicted lesion maps achieved a mean structural similarity index of 0.749 and a mean normalized inner product of 0.867 when comparing maps obtained in PBS and blood. Catheter-based NIRS can precisely detect RFA lesions on left atria submerged in blood. Optical parameters are reliable in blood and without perpendicular contact, confirming their ability to provide useful feedback during in vivo RFA procedures.

Remote monitoring of atrial fibrillation recurrence using mHealth technology (REMOTE-AF).

This proof-of-concept study sought to evaluate changes in heart rate (HR) obtained from a consumer wearable device and compare against implantable loop recorder (ILR)-detected recurrence of atrial fibrillation (AF) and atrial tachycardia (AT) after AF ablation. REMOTE-AF (NCT05037136) was a prospectively designed sub-study of the CASA-AF randomized controlled trial (NCT04280042). Participants without a permanent pacemaker had an ILR implanted at their index ablation procedure for longstanding persistent AF. Heart rate and step count were continuously monitored using photoplethysmography (PPG) from a commercially available wrist-worn wearable. Photoplethysmography-recorded HR data were pre-processed with noise filtration and episodes at 1-min interval over 30 min of HR elevations (Z-score = 2) were compared with corresponding ILR data. Thirty-five patients were enrolled, with mean age 70.3 ± 6.8 years and median follow-up 10 months (interquartile range 8-12 months). Implantable loop recorder analysis revealed 17 out of 35 patients (49%) had recurrence of AF/AT. Compared with ILR recurrence, wearable-derived elevations in HR ≥ 110 beats per minute had a sensitivity of 95.3%, specificity 54.1%, positive predictive value (PPV) 15.8%, negative predictive value (NPV) 99.2%, and overall accuracy 57.4%. With PPG-recorded HR elevation spikes (non-exercise related), the sensitivity was 87.5%, specificity 62.2%, PPV 39.2%, NPV 92.3%, and overall accuracy 64.0% in the entire patient cohort. In the AF/AT recurrence only group, sensitivity was 87.6%, specificity 68.3%, PPV 53.6%, NPV 93.0%, and overall accuracy 75.0%. Consumer wearable devices have the potential to contribute to arrhythmia detection after AF ablation. ClinicalTrials.gov Identifier: NCT05037136 https://clinicaltrials.gov/ct2/show/NCT05037136.