First-time Catheter Ablation Research Articles

Posterior left atrial wall isolation for treatment of persistent atrial fibrillation during first-time catheter ablation: An updated systematic review and meta-analysis.

Although catheter ablation (CA) by mean of pulmonary vein isolation (PVI) is nowadays the mainstay treatment for atrial fibrillation (AF), its success-rate in persistent AF remains suboptimal. Results from studies evaluating whether adding posterior wall isolation (PWI) to PVI can increase the success-rate of CA in persistent AF have yielded conflicting data. The aim of this meta-analysis was to assess whether PWI plus PVI might be beneficial in patients with persistent AF. Electronic databases were searched for randomized control trials (RCTs) and observational studies that compared clinical outcomes between patients with persistent AF who underwent PVI with or without PWI. Fifteen studies, including a total of 3072 patients, were considered (1533 treated with PVI and 1539 with PWI + PVI). Comparing patients treated with or without PWI, no statistically significant difference was found in the risk of any atrial tachyarrhythmias recurrence after CA (RR 0.83; 95 % CI 0.66-1.03). The analyses detected a statistically significant reduction in the risk of AF in patients treated with PWI (RR 0.63; 95 % CI 0.48-0.84) balanced by a trend towards an increased risk of atrial flutter/atrial tachycardia (RR 1.51; 95 % CI 0.92-2.49). No statistically significant differences were identified in the risk of major procedural complications (RR 0.94; 95 % CI 0.50-1.78). According to our updated meta-analysis, the addition of PWI to PVI was not associated with a reduction of atrial arrhythmia recurrences. A reduction of the risk of AF recurrence and a trend towards an increased risk of atrial flutter/atrial tachycardia were identified.

Superior Vena Cava Isolation With Cryoballoon in AF Ablation: Randomized CAVAC AF Trial.

Superior vena cava (SVC) has been considered a specific trigger in atrial fibrillation development. We investigated the efficacy and safety of combining cryoballoon pulmonary vein isolation (PVI) with SVC ablation compared with PVI alone in 100 patients with paroxysmal or non-long-standing persistent atrial fibrillation. Patients were randomly assigned to either the PVI+SVC ablation group or the PVI-only group. Each patient was given a mobile device to record a daily ECG and detect atrial tachyarrhythmias. The primary end point, freedom from any atrial tachyarrhythmia recurrence between 91 and 365 days post-catheter ablation, did not significantly differ between the 2 groups (62.9% versus 72%; P=0.41). However, the PVI+SVC group exhibited higher rates of phrenic nerve paralysis (20.8% versus 6%; P=0.003) and transient sinus node injury (18.8% versus 0%; P=0.001) compared with the PVI-only group. The median burden of atrial tachyarrhythmia showed no significant difference (P=0.91). The addition of SVC ablation to PVI did not enhance freedom from atrial tachyarrhythmia at 12 months, and it led to increased complications. These findings do not support the routine inclusion of SVC ablation in cryoballoon procedures for first-time catheter ablation in patients with paroxysmal or non-long-standing persistent atrial fibrillation.

Contractile reserve is associated with response to catheter ablation in patients with atrial fibrillation and left ventricular systolic dysfunction

Abstract Background Although patients with atrial fibrillation (AF) and left ventricular systolic dysfunction (LVSD) can benefit from catheter ablation, some patients do not respond. Prospectively identifying responders is challenging. Contractile Reserve (CR) on Exercise Stress Echocardiography (ESE) has demonstrated stratifying value before cardiac resynchronisation therapy but has not been evaluated in the setting of AF. Objective To evaluate whether CR on ESE was associated with response to CA in patients with LVSD. Methods Patients with persistent AF and LVSD (LVEF <50%) undergoing first-time catheter ablation were enrolled in the AFHF study. Patients underwent trans-thoracic echocardiography at rest and maximum exertion using a recumbent cycle ergometer. CR was the difference in LVEF at maximum exertion versus rest. Echocardiography was repeated six months after successful catheter ablation to determine Response based on the Universal Definition of Heart Failure improvement (LVEF +10%, or if baseline LVEF >40% then LVEF>50%). Results 52 patients were enrolled with baseline demographics in Table 1. 39 patients completed follow-up with 32 (82%) being responders. Responders had greater CR than non-responders (+10% (+5, +12) vs 3% (0, +4), (p=0.008)). A CR ≥ 5% had a positive predictive value of 0.96 for Response in this cohort. The AUROC was 0.83 with a specificity of 0.86. This was also associated with significant improvement in reported Minnesota living with HF scores (p<0.01). Conclusion CR was associated with response to CA in patients with persistent AF and LVSD in this exploratory analysis. Validation in an external cohort is needed to evaluate fit before prospective evaluation of its clinical utility.Baseline CharacteristicsROC curve for response to ablation

Duration of sinus rhythm after direct current cardioversion does not predict recurrence of atrial fibrillation after subsequent catheter ablation: a multicentre study

Abstract Background Catheter ablation (CA) for persistent atrial fibrillation (PsAF) is associated with high rates of AF recurrence. DC cardioversion (DCCV) is often performed before CA, with wide variation in duration of maintenance of sinus rhythm (SR) post-DCCV. Factors associated with short duration of SR after DCCV, such as raised body mass index, prior duration of AF, prolonged p wave duration on the 12-lead ECG, and indexed left atrial volume, are either associated with or indicative of atrial electrical and structural remodelling, suggesting that shorter duration of SR after DCCV reflects a more advanced substrate for AF, which could in turn also influence the likelihood of success after CA. Objective To determine if post-DCCV SR duration is associated with AF recurrence after subsequent CA. Methods We performed a multicentre retrospective study of patients undergoing first-time CA for PsAF between 2015-2018 with prior DCCV. SR duration after the last DCCV prior to CA was recorded. The primary outcome was the first recurrence of atrial arrhythmia post-CA (after a 90-day post-CA blanking period). We also performed a pre-specified sensitivity analysis for amiodarone use at DCCV, by performing repeat analysis after excluding all such patients across the three groups. Results A total of 331 patients were identified across five centres and categorised by post-DCCV SR duration: <7 days (group 1); 7-31 days (group 2); >31 days (group 3; Table 1). Over median post-CA follow-up of 591 days, 207 patients (62.5%) met the primary outcome. There was no significant between-group difference in the time to primary outcome (log rank p=0.82; Figure 1). There were significantly more blanking period arrhythmias in groups 1 and 2 than group 3 after post hoc Bonferroni correction (pairwise p=0.001, 0.002 respectively; Table 1). After exclusion of patients on amiodarone at time of DCCV, there remained no significant between-group difference in the time to primary outcome (log rank p=0.85). Conclusion Shorter duration of SR post-DCCV is associated with blanking period arrhythmia after CA, but crucially does not predict long-term AF recurrence. Early AF recurrence after DCCV should not influence decisions on CA suitability or be used to predict long-term CA success.

Timing of early recurrence of atrial fibrillation during the blanking period after catheter ablation for persistent atrial fibrillation and implications for long-term success: a multicentre study

Abstract Background After catheter ablation (CA) for atrial fibrillation (AF), early recurrences of AF (ERAF) that occur within a 90-day post-ablation "blanking period" are considered to represent transient post-ablation pro-arrhythmia. Purpose To determine if the timing of early recurrence of AF during the traditional 90-day post-CA blanking period is associated with long-term AF recurrence after CA for persistent AF (PsAF). Methods We performed a multicentre retrospective study of patients undergoing first-time CA for PsAF between 2015-2018. All patients had undergone pre-CA DCCV. Incidences of ERAF during the post-CA blanking period were reviewed, and patients were categorised into three groups based on the timing of last episode of ERAF during the blanking period: (1) no ERAF (reference population); (2) last ERAF <30 days post-CA; (3) last ERAF 31-90 days post-CA. The primary outcome was long-term recurrence of atrial arrhythmia, i.e. time to first recurrence of atrial arrhythmia occurring beyond the first 90 days after CA. Patients who had ERAF and exited the blanking period in AF (i.e. those with immediate recurrence at 90 days) were excluded from this analysis. Results 331 patients were identified from five centres. 206 patients had no ERAF during follow-up, 124 patients had ERAF during the blanking period, and in one patient the presence of ERAF was not documented. Of the 124 patients experiencing ERAF during the 90-day post-CA blanking period, the timing of the last episode was known in 122 patients (Table 1). Of these, 58 patients exited the 90-day blanking period in AF and were excluded. Over median post-CA follow-up of 590 days, 147 patients (54%) experienced the primary outcome. Compared with Group 1 (no ERAF), ERAF within each of the time periods was associated with a statistically significant progressively increased risk of long-term recurrence (Group 2, last ERAF <30 days post-CA: hazard ratio [HR] 1.95 [95% CI 1.15-3.31]; Group 3, last ERAF 31-90 days post-CA: HR 4.86 [95% CI 2.13-11.08]; Figure 1). Conclusion ERAF during the traditional 90-day post-CA blanking period is associated with long-term AF recurrence, with later recurrence within the 90-day period conferring greater risk. Patients with ERAF during the blanking period may need to be considered for earlier repeat intervention where clinically appropriate.

Ablation strategy for patients with atrial fibrillation and heart failure - a Danish nationwide cohort study

Abstract Introduction Atrial fibrillation (AF) patients with heart failure (HF) face increased risks of AF recurrence and HF admission. Catheter ablation (CA) is a recognized treatment option. Due to observed atrial remodelling and fibrosis associated with ventricular remodelling in HF patients, it could be suggested that a more comprehensive ablation strategy should be applied for these patients. Purpose To examine the risk of AF recurrence and HF admission by ablation strategy for patients with AF and HF. Method This nationwide cohort study was conducted using real-life data from Danish healthcare registries. All patients above 18 years of age, with a diagnosis of AF and HF that underwent first-time CA from January 1st 2010 to December 31st 2018, were identified and included at the date of ablation. Exposure of interest was ablation strategy - pulmonary vein isolation (PVI) or additional ablation to PVI (PVI plus). PVI plus was defined as either roofline, mitral linear ablation, posterior wall isolation, complex fractionated atrial electrograms or ganglionated plexi ablation. Primary endpoint was HF admission and AF recurrence after a 3-months blanking period. AF recurrence was defined by a composite endpoint of first-reached endpoint of either use of antiarrhythmic drugs, AF admission, electrical cardioversions, or AF re-ablation. The relative rates of recurrent AF and HF admission by ablation strategy (PVI or PVI plus) were examined by Cox proportional models using PVI as reference. The analyses were adjusted for clinically important baseline characteristics including age, sex, AF type (paroxysmal or persistent), diagnosis-to-ablation time, procedural year, body mass index, size of left atrium, as well as co-morbidities such as ischemic heart disease, chronic obstructive pulmonary disease, chronic kidney disease, hypertension, and diabetes. Results The study cohort consisted of 1,270 patients diagnosed with AF and HF undergoing first-time CA, of which 1,119 (88%) received PVI and 151 (12%) received PVI plus. 80% where males in both groups. Median age was 62 for the PVI group and 64 for the PVI plus group. Severely enlarged left atrium, ischemic heart disease and use of amiodarone were more prevalent in the PVI plus group compared to the PVI group (Table 1). The relative risk of recurrent AF showed a hazard ratio of 1.02 (95% CI: 0.77-1.37) for the PVI plus group compared to the PVI group, and for HF admission the hazard ratio was 0.95 (95% CI: 0.55-1.65) for the PVI plus group compared to the PVI group (Figure 1). Conclusion No significant differences in AF recurrence and HF admission were observed between PVI and PVI plus strategy in AF and HF patients in this observational study. With a diagnosis-to-ablation time exceeding 3 years, it could be argued that advanced atrial remodelling may diminish the impact of reverse atrial remodelling after catheter ablation, irrespective of the ablation strategy employed.Table 1Figure 1

Elucidating the mechanism of rapid functional recovery following atrial fibrillation ablation in patients with left ventricular systolic dysfunction

Abstract Introduction Successful sinus rhythm restoration by catheter ablation (CA) of atrial fibrillation (AF) rapidly improves cardiac function in patients with left ventricular (LV) systolic dysfunction. However, the underlying mechanism of this recovery remains unknown. Purpose To elucidate the mechanism of the functional recovery after CA of AF and systolic dysfunction. Methods We retrospectively examined 4001 consecutive patients who underwent first-time CA of AF between 2012 and 2021 at our institution. Of them, 505 patients had baseline LV ejection fraction (LVEF) of <50%. Among them, we enrolled 454 patients who received electrocardiogram-gated contrast-enhanced 256-slice multi-detector computed tomography (MDCT) (Brilliance iCT, Philips Medical Systems, Cleveland, Ohio) both at baseline and 3 months after CA. Changes in LV measures, wall thickness, and LV mass were examined based on MDCT data. Results A reduction of LV end-systolic volume (LVESV) (from 71 ± 37 ml to 46 ± 34 ml, p <0.001) and improvement of LVEF (from 39 ± 9% to 62 ± 14%, p <0.001) were observed after CA. However, there was no significant change in LV end-diastolic volume (LVEDV) (from 118 ± 49 ml to 116 ± 46 ml, p = 0.13). Mean wall thickness during diastole did not change (from 7.1 ± 1.4 mm to 7.1 ± 1.4 mm, p = 0.94), either. However, wall thickness during systole significantly changed after CA (from 10.0 ± 1.7 mm to 12.7 ± 2.8 mm, p <0.001). As a result, there was no significant change in LV mass after CA (from 84.3 ± 28.7 g to 84.4 ± 28.1 g, p = 0.88). A regression analysis revealed a significant inverse correlation between the delta LVEF and delta LVESV (r = -0.59, p <0.001). However, the delta LVEF was not correlated with the delta LVEDV and delta LV mass. Conclusions The rapid improvement of LVEF after CA of AF was attributed to a decrease in the LVESV. Unchanged LV mass indicated that this functional recovery was solely a mechanical issue, without evidence of myocyte regression.

Peak VO2 is associated with cardiac functional response and long-term survival in patients with heart failure and atrial fibrillation undergoing catheter ablation

Abstract Background Contemporary guidelines recommend Catheter Ablation (CA) in patients with persistent Atrial Fibrillation (AF) with Heart Failure with reduced ejection fraction (HFrEF). It is challenging to prospectively predict who will respond. We have previously described the long-term survival outcomes of patients in this cohort.(1) However, the clinical characteristics associated with HF response and long-term clinical outcomes have not been reported. Objective To evaluate the association of HF parameters with cardiac functional response to CA and long-term survival after CA. Methods Post-hoc, long-term follow-up of mortality was undertaken in patients enrolled in the CAMTAF and ARC-HF RCTs. Both studies enrolled patients with persistent AF and HFrEF between 2005 and 2012 and randomised to first-time CA or medical therapy alone. Left ventricular ejection fraction (LVEF) and peak VO2 were measured in both studies at baseline and 12-month follow-up. The Universal Definition of HF response (LVEF improves by >10% points or to an LVEF >50%) was used.(2,3) Multi-variate logistic regression was used to determine features associated with HF response and Cox proportional hazards modelling for survival. Results 102 patients underwent randomisation with 52 assigned to CA. The mean age was 60.2 ±10.7 years with 93 (91.2%) male. The mean Baseline LVEF was 31 ±11% and peak VO2 was 1815 ±642mlmin-1. Baseline LVEF did not correlate significantly with Minnesota Living with Heart Failure (MLWHF) score (r=-0.11, p=0.29) whereas baseline peak VO2 did (r=-0.28, p<0.01). In patients randomised to CA, the median (IQR) improvement in LVEF was +8.4% (0, 15%). 22/52 (42.3%) patients were classified as Responders based on the Universal Criteria. Responders were younger (54.7 ±10.6 years vs 61.8 ±11.4, p=0.03) and had a higher mean HR on baseline Holter monitoring (89 ±14bpm vs 79 ±11bpm p<0.01) than non-responders. There was no significant difference in sex, baseline MLWHF scores, BNP levels or LVEF between groups (28±9% vs 31 ±9%, p=0.19). Responders had a significantly higher peak VO2 at baseline than Non-Responders (1972 ±668mlmin-1 vs 1556 ±580mlmin-1, p=0.03). On multivariate analysis, mean heart rate on Holter monitoring and peak VO2 were significantly associated with Responder status post-ablation. (Table 1a) During a median follow-up of 7.8 (3.9 –9.9) years, 34 (33.3%) patients died, including 17 (32.7%) patients in the CA arm. On univariate analysis, baseline peak VO2 was significantly greater of survivors at 5 years (1867 ±624 mlmin-1 vs 1259 ±497 mlmin-1, p<0.01). On multivariate Cox regression analysis, the peak VO2 at baseline was the only significant predictor of survival (Table 1b). Conclusion Peak VO2 at baseline was associated with baseline symptom status, the short-term LVEF response to CA and long-term survival and may be a useful stratification tool to aid patient selection for CA.1a. Regression for 6-month LVEF response1b. Regression for long-term mortality

Early ablation leads to better outcome in patients < 55 years with persistent atrial fibrillation

The question of optimal timing for catheter ablation of atrial fibrillation (AF) to achieve best outcomes remains a crucial clinical issue. As AF occurs less frequently in younger patients, data regarding Diagnosis-to-Ablation Time (DAT) is especially limited in patients under the age of 55 years with persistent AF. We therefore analyzed the temporal relationship between initial AF presentation and timing of catheter ablation in this cohort. We conducted a retrospective single-centre study of patients ≤ 55 years with persistent AF who underwent first-time catheter ablation at our center. The cohort was divided into patients that underwent catheter ablation after diagnosis of persistent AF within a DAT of ≤ 12 months and patients with a DAT of > 12 months. A total of 101 patients (median age 51 years; female n = 19 (18.8%)) with persistent AF were included. Ablation was performed within 12 months (“early DAT”) in 51 patients and > 12 months (“late DAT”) in 50 patients. Pulmonary vein isolation was performed using high-power short-duration (HPSD) radiofrequency ablation. Median DAT was 5 months (1–12 months) in the early ablation group and 36 months (13–240 months) in the late ablation group. The median follow-up was 11.3 months (0.03–37.1 months). The rate of any atrial arrhythmia recurrence after a 30-day blanking period was significantly lower in the early DAT group (13/51 patients; 25.5%) as compared to the late DAT group (26/50 patients; 52.0%) (log rank test; p = 0.003). Catheter ablation performed > 12 months after the initial AF diagnosis was an independent predictor for the occurrence of any atrial arrythmia (OR: 2.58; (95%-CI: 1.32–5.07). Early first-time catheter ablation (DAT ≤ 12 months) in patients ≤ 55 years with persistent AF is associated with a significantly lower rate of arrhythmia recurrence.

Temporal trends of catheter ablation procedures in patients with atrial fibrillation and atrial flutter: A nationwide cohort study

BackgroundCatheter ablation is a well-established treatment to prevent atrial fibrillation (AF) and atrial flutter (AFL) recurrences and to relieve symptoms, whereas pacemaker implantation and atrioventricular node (AVN) ablation is used for rate control when medical therapy fails. AimsWe investigated temporal trends and patient characteristics in catheter ablation procedures for AF, AFL and AVN in Finland between 2012–2018. MethodsFinnish AntiCoagulation in Atrial Fibrillation (FinACAF) is a registry-based study including all patients with AF or AFL in Finland between 2012–2018. ResultsThe number of patients with AF or AFL diagnosis in Finland increased from 185057 to 243802 between 2012–2018 and a total of 8954 first-time catheter ablation procedures were performed. Of them, 4909 (54.8 %) were AF ablations, 2731 (30.5 %) AFL ablations and 1314 (14.7 %) AVN ablations. The procedural numbers increased from 457/year to 934/year for AF, from 223/year to 553/year for AFL and from 114/year to 238/year for AVN. Altogether, 0.65% of all patients with diagnosed AF or AFL underwent AF, AFL or AVN ablation in 2018. The mean age of the patients increased in all ablation groups. Patients undergoing AF and AFL ablations were predominantly men (69.7 % and 74.6 % respectively) whereas patients undergoing AVN ablation were more often women (56.9%). ConclusionsThe use of catheter ablation more than doubled during 2012–2018 and the increase was particularly seen in the elderly patients. Nevertheless, only a minority of AF and AFL patients were treated with catheter ablations.

Effect of Pulmonary Vein Isolation with Left Atrial Wall Isolation Plus Selective CFAE Ablation in Patients with Persistent Atrial Fibrillation.

Pulmonary vein isolation (PVI) is a foundational treatment for persistent atrial fibrillation (PeAF), but the effectiveness of adding posterior wall isolation (PWI) and selective complex fractionated atrial electrogram (CFAE) ablation in the roof and anterior wall remains debated. The potential of these additional ablation techniques to improve long-term outcomes for PeAF patients is still uncertain. This retrospective study included 151 PeAF patients who underwent first-time catheter ablation at our center. The choice of ablation strategy was based on the operator's clinical judgment, taking into account the patient's specific condition and anatomical features. Patients were divided into two groups: the PVI group, which received PVI alone, and the modified PWI (MPWI) group, which received PVI along with additional PWI and selective CFAEs ablation in the roof and anterior wall. The primary endpoint was the absence of atrial arrhythmia lasting more than 30 s, without antiarrhythmic drugs, at 12 months. At the 12-month follow-up, 77.3% of the patients in the MPWI group and 52.1% of the patients in the PVI group remained in sinus rhythm without an atrial arrhythmia recurrence (p = 0.001). The BIC-based Cox regression analysis identified the ablation strategy and atrial fibrillation (AF) duration as independent predictors of recurrence across the cohort. It was found that MPWI significantly reduced the risk of recurrence, while a longer AF duration increased it. In the MPWI group, AF duration, left ventricular internal diameter in systole (LVIDs), and moderate or greater tricuspid regurgitation were independent predictors of recurrence. In the PVI group, only the left atrial low voltage area (LVA) index was a significant predictor. The addition of PWI and selective CFAE ablation to PVI significantly improves 12-month arrhythmia-free survival compared to PVI alone, demonstrating the superiority of this combined approach in improving long-term outcomes for patients with persistent AF.

General anaesthesia compared to conscious sedation for first-time atrial fibrillation catheter ablation-a Danish nationwide cohort study.

Catheter ablation (CA) is a well-established treatment option for atrial fibrillation (AF), where sedation and analgesia are pivotal for patient comfort and lesion formation. The impact of anaesthesia type on AF recurrence rates remains uncertain. This study aimed to examine AF recurrence rates depending on conscious sedation (CS) vs. general anaesthesia (GA) during CA. Utilizing nationwide data from the Danish healthcare registries, we conducted this cohort study involving adults (≥18 years) undergoing first-time CA for AF between 2010 and 2018. Patients were categorized by anaesthesia type (CS or GA), with the primary endpoint being AF recurrence, defined by a composite endpoint of either antiarrhythmic drug (AAD) prescriptions, AF-related hospital admissions, electrical cardioversions, or AF re-ablation. The impact of anaesthesia type was evaluated using multivariable Cox proportional hazards analysis. The study cohort comprised 7957 (6421 CS and 1536 GA) patients. Persistent AF, hypertension, and heart failure, as well as use of AAD, were more prevalent in the GA group. Cumulative incidences of recurrent AF were higher in the CS group at 1 (46% vs. 37%) and at 5 (68% vs. 63%) years. Multivariate analysis revealed CS as significantly associated with increased risk of AF recurrence at 5-year follow-up [hazard ratio 1.26 (95% confidence interval 1.15-1.38)], consistent across paroxysmal and persistent AF subtypes. This nationwide cohort study suggests a higher risk of AF recurrence with CS during CA compared to GA. These results advocate for considering GA as the preferred anaesthesia type for improved CA outcomes.

First-time catheter ablation outcomes for atrial fibrillation are dependent on low-voltage areas rather than paroxysmal vs. persistent classifications: a REAL-AF study

Abstract Background Left atrial low-voltage areas (LA LVA) measured at time of catheter ablation for atrial fibrillation (AF) have been increasingly recognized as an indicator of atrial fibrosis [1]. However, little is known whether first-time catheter ablation outcomes differ between paroxysmal AF (PAF) and persistent AF (PerAF) in patients with higher LA LVA, which may indicate a more advanced substrate independent of clinical subtype. Purpose To evaluate whether outcomes of first-time catheter ablation for AF are dependent on LA LVA rather than PAF vs. PerAF types in a multicenter registry of patients. Methods The Real-world Experience of Catheter Ablation for the Treatment of Symptomatic PAF and PerAF Using Novel Contact Force Technologies registry (REAL-AF) is a prospective, observational multicenter registry of patients undergoing catheter ablation. We evaluated 4181 patients undergoing first-time catheter ablation for both PAF and PerAF to determine AF recurrence within 12 months. Contact maps were created using a 5-spline high-density catheter. LA LVA was calculated using these contact maps based on a bipolar voltage of &amp;lt;0.50 mV. LA LVA was categorized into low (&amp;lt;5%) vs. high (≥5%) based on preliminary data. Risk of recurrence was analyzed using Cox proportional hazard models. Results Patients with LA LVA ≥5% who underwent first-time catheter ablation for AF (both PAF and PerAF) experienced a higher risk of AF recurrence within 12 months (Hazard ratio (HR): 1.95, p&amp;lt;0.001), see Figure 1. Overall, 82.0% of patients were free of AF in the LA LVA &amp;lt;5% group compared to 69.1% in the LA LVA ≥5% group. This association remained significant in a subpopulation of patients presenting in normal sinus rhythm (N = 2463) at time of ablation (HR: 1.90, p&amp;lt;0.001). 12-month ablation outcomes between PAF and PerAF in patients with LA LVA ≥5% (N = 1590) were not statistically significant (71.0% vs 67.3% respectively, HR: 1.15, p=0.30), see Figure 2. Finally, in the LA LVA &amp;lt;5% group (N = 2591), patients with PerAF had a 1.42 times higher risk for AF recurrence within 12 months after catheter ablation (p=0.04). Conclusion This is the largest real-world registry to date demonstrating that LA LVA ≥5% is associated with a higher risk of AF recurrence within 12 months in patients undergoing first-time catheter ablation for AF. Among patients with LA LVA ≥5%, AF recurrence was not associated with AF type. These findings motivate further studies into using LA LVA as a prognostic tool for patients undergoing first-time catheter ablation for AF and using non-invasive methods to assess this in order to stratify patients further.

Identifying patients with reduced risk of recurrences after ablation for persistent atrial fibrillation

Abstract Background Catheter ablation (CA) is a well-established treatment option for recurrent atrial fibrillation (AF), and has shown to outperform antiarrhythmic drugs in prevention of AF recurrences in numerous studies. However, up to 50% of patients with persistent AF (peAF) will experience recurrences after first-time CA. Improving treatment for these patients involves, choosing the right patients for the ablation procedure, optimizing the timing of the procedure, and using the most effective ablation strategy. This will benefit not only the patients, but also target recourse use in the healthcare system. Purpose To identify characteristics and comorbidities of patients with peAF associated with a reduced risk of recurrence after CA. Additionally, to investigate the optimal timing and ablation strategy. Methods This observational cohort study was conducted using real-life data from the Danish healthcare registries. All patients with peAF, &amp;gt;18 years of age, who were assigned to first-time AF ablation, were included within the study period from January 1st 2010 to December 31st 2018. A composite endpoint for AF recurrences was defined as either AF admission, electric cardioversion, use of antiarrhythmic drugs or re-ablation after a 3-month blanking period. We followed the patients in the registries for up to 5 years. A Cox proportional hazards analysis was performed to identify specific patient characteristics, comorbidities, timing of ablation and ablation strategy associated with reduced risk of AF recurrences after ablation. Results The study cohort consisted of 2,123 patients with peAF undergoing first-time CA. Median age was 63 years [IQR: 56.10;68.90], 77.7% were male, and mean BMI was 28.40 (SD: 4.97). Mean diagnosis-to-ablation-time (DAT) was 3.56 years (SD: 4.25) and mean follow-up time was 928.3 days (SD: 829.62). Most prevalent co-morbidities were hypertension (59.1%), ischemic heart disease (16.9%), and heart failure (HF) (27.7%) (Table 1). Patients characterized by male sex (HR: 0.80, 95% CI 0.69-0.93), age 60-70 (HR: 0.79, 95% CI 0.67-0.93), and absence of co-morbidities such as HF (HR: 0.81, 95% CI 0.70-0.94) and chronic obstructive pulmonary disease (COPD) (HR: 0.58, 95% CI 0.44-0-75), were observed with a significantly reduced relative risk of recurrent AF. Short DAT(&amp;lt;1 year) was associated with a 24% lower risk of recurrence compared to longer (&amp;gt;2 years). Furthermore, PVI Plus (additional ablation to PVI) was not significantly associated with a reduced risk of recurrences (HR: 1.10, 95% CI 0,92-1.31) (Figure 1). Conclusion To obtain rhythm control for patients with peAF is a great challenge. This observational study with more than 2,000 patients, identifies patients most likely to benefit from CA. Lower recurrence rates were observed in younger patients (&amp;lt;70 years), absence of especially HF and COPD, and early ablation (&amp;lt;1 year). Notably, PVI plus did not reduce the risk of recurrences.

Associations between stroke risk factors and left atrial low-voltage areas in patients with atrial fibrillation undergoing catheter ablation from the REAL-AF registry

Abstract Background Prior research indicates that increased left atrial low-voltage areas (LA LVA) are linked to comorbidities and CHA2DS2-VASc score in patients with persistent atrial fibrillation (PerAF) undergoing catheter ablation. However, given the heterogeneity of AF where patients may transition between paroxysmal AF (PAF) and PerAF types, it is biologically plausible that these associations span all forms of AF. Purpose To investigate the relationship of stroke demographics and comorbidities to LA LVA and AF type in a multicenter registry of patients undergoing catheter ablation. Methods The Real-world Experience of Catheter Ablation for the Treatment of Symptomatic PAF and PerAF Using Novel Contact Force Technologies registry (REAL-AF) is a prospective, observational multicenter registry of patients undergoing catheter ablation. We evaluated 6053 patients undergoing first-time catheter ablation for both PAF and PerAF to identify associations between stroke risk factors and LA LVA. LA LVA was determined in contact maps as bipolar voltage &amp;lt;0.50 mV. Mapping was completed using 5-spline high-density catheters before ablation. LA LVA was categorized into low (&amp;lt;5%) vs. high (≥5%) based on preliminary data. Analyses were conducted using independent samples t-test and Chi-square test. Results LA LVA was associated with greater CHA2DS2-VASc score (3.2 vs. 2.5, p &amp;lt;0.001). Age 75+ (Odds ratio (OR): 2.22, p&amp;lt;0.001), congestive heart failure (CHF) (OR: 2.01, p&amp;lt;0.001), female sex (OR): 1.51, p&amp;lt;0.001), vascular disease (OR: 1.50, p&amp;lt;0.001), age 65-74 (OR: 1.20, p=0.001), hypertension (OR: 1.38, p&amp;lt;0.001), history of stroke (OR: 1.29, p=0.004) and diabetes (OR: 1.25, p=0.001) were also associated with LA LVA (Table 1). These associations remained significant among a subgroup of those presenting in normal sinus rhythm (N = 3546). Patients with CHF (OR: 2.09, p&amp;lt;0.001), hypertension (OR: 1.89, p&amp;lt;0.001) and male sex (OR: 0.60, p&amp;lt;0.001) were more likely to have PerAF in the LVA ≥5% subgroup (n=1594) (Table 2). All other components of the CHA2DS2-VASc score were not significantly associated with AF type in this subgroup. While there was a significant association between AF type and CHA2DS2-VASc score (PAF: 3.15, PerAF: 3.42, p&amp;lt;0.001) in the LA LVA ≥5% subgroup, the effect size was small (Cohen’s d = -0.179). Conclusion LA LVA ≥5% was associated with all separate components and overall CHA2DS2-VASc score. In patients with LA LVA ≥5%, there were only associations between PerAF and CHF, hypertension, and male sex, implying a special role in substrate progression. Our findings suggest that LA LVA may represent a more sensitive clinical phenotyping tool of AF rather than current duration-based ones. This is the largest study to our knowledge in elucidating the relationship between increased LA LVA and stroke risk factors in the AF population.

Reduced dementia risk in patients with optimized anticoagulation therapy undergoing atrial fibrillation ablation

BackgroundAtrial fibrillation (AF) is associated with the development of dementia, and observational studies have shown that oral anticoagulation and catheter ablation reduce dementia risk. However, such studies did not consistently report on periprocedural anticoagulation and long-term oral anticoagulation coverage, for which reason the separate effect of AF ablation on dementia risk could not be established. ObjectiveWe evaluated the protective effect of AF ablation in a large cohort of patients who received optimized anticoagulation and compared them with patients who were managed medically. MethodsWe retrospectively included 5912 consecutive patients who underwent first-time catheter ablation for AF between 2008 and 2018 and compared them with 52,681 control individuals from the Swedish Patient Register. Propensity score matching produced 2 cohorts of equal size (n = 3940) with similar baseline characteristics. Dementia diagnosis was identified by International Classification of Diseases codes from the patient register. ResultsMost propensity score–matched patients were taking an oral anticoagulant at the start (94.5%) and end (75.0%) of the study. Mean follow-up was 4.9 ± 2.8 years. Catheter ablation was associated with lower risk for the dementia diagnosis compared with the control group (hazard ratio [HR], 0.44; 95% confidence interval [CI], 0.22–0.86; P = .017). The result was similar when including patients with a stroke diagnosis before inclusion (HR, 0.50; 95% CI, 0.28–0.89; P = .019) and after adjustment for the competing risk of death (HR, 0.41; 95% CI, 0.20–0.86; P = .018). ConclusionCatheter ablation of AF in patients with optimized oral anticoagulation therapy was associated with a reduction in dementia diagnosis, even after adjustment for potential confounders and for competing risk of death.

Deep learning-based workflow for automatic extraction of atria and epicardial adipose tissue on cardiac computed tomography in atrial fibrillation.

Preoperative estimation of the volume of the left atrium (LA) and epicardial adipose tissue (EAT) on computed tomography (CT) images is associated with an increased risk of atrial fibrillation (AF) recurrence. We aimed to design a deep learning-based workflow to provide reliable automatic segmentation of the atria, pericardium, and EAT for future applications in the management of AF. This study enrolled 157 patients with AF who underwent first-time catheter ablation between January 2015 and December 2017 at Taipei Veterans General Hospital. Three-dimensional (3D) U-Net models of the LA, right atrium (RA), and pericardium were used to develop a pipeline for total, LA-EAT, and RA-EAT automatic segmentation. We defined fat within the pericardium as tissue with attenuation between -190 and -30 HU and quantified the total EAT. Regions between the dilated endocardial boundaries and endocardial walls of the LA or RA within the pericardium were used to detect voxels attributed to fat, thus estimating LA-EAT and RA-EAT. The LA, RA, and pericardium segmentation models achieved Dice coefficients of 0.960 ± 0.010, 0.945 ± 0.013, and 0.967 ± 0.006, respectively. The 3D segmentation models correlated well with the ground truth for the LA, RA, and pericardium ( r = 0.99 and p < 0.001 for all). The Dice coefficients of our proposed method for EAT, LA-EAT, and RA-EAT were 0.870 ± 0.027, 0.846 ± 0.057, and 0.841 ± 0.071, respectively. Our proposed workflow for automatic LA, RA, and EAT segmentation using 3D U-Nets on CT images is reliable in patients with AF.

Two decades of SVT ablation in Denmark: a trend towards higher age, more comorbidity, and less prior use of antiarrhythmic and rate-limiting pharmacotherapy—a nationwide registry-based Danish study

Background and aimsTrends in patient selection and use of pharmacotherapy prior to catheter ablation (CA) for supraventricular tachycardia (SVT) are not well described. This study examined temporal trends in patients undergoing first-time CA for regular SVT, including atrioventricular nodal re-entry tachycardia (AVNRT), accessory pathways (APs), and ectopic atrial tachycardia (EAT) on a nationwide scale in Denmark in the period 2001–2018.Methods and resultsUsing Danish Nationwide registers, 9959 patients treated with first-time CA for SVT between 2001 and 2018 were identified, of which 6023 (61%) received CA for AVNRT, 2829 (28%) for AP, and 1107 (11%) for EAT. Median age was 55, 42, and 55 in the AVNRT, APs, and EAT group, respectively. The number of patients receiving CA increased from 1195 between 2001 and 2003 to 1914 between 2016 and 2018. The percentage of patients with a CHA2DS2-VASc score ≥ 2 increased in all patient groups. The number of patients who underwent CA with no prior use of antiarrhythmic- or rate limiting medicine increased significantly, though prior use of beta-blockers increased for AVNRT patients. Use of verapamil decreased in all three SVT groups (P < 0.05). Use of amiodarone and class 1C antiarrhythmics remained low, with the highest usage among EAT patients.ConclusionBetween 2001 and 2018, CA was increasingly performed in patients with SVT, primarily AVNRT- and EAT patients. The burden of comorbidities increased. Patients undergoing CA without prior antiarrhythmic- or rate-limiting drug therapy increased significantly. Use of beta-blockers increased and remained the most widely used drug.Graphical

Is frailty associated with greater symptom burden following catheter ablation for atrial fibrillation?

Abstract Background Previous, small studies have found that the effectiveness of catheter ablation among patients with atrial fibrillation (AF) is affected by frailty. However, whether the symptom burden after catheter ablation varies according to frailty remains uncertain. Purpose We aimed to assess whether severity of patient frailty modified the recurrence of AF in the year after first-time catheter ablation for AF including proportion of hospital admissions with AF. Methods We identified patients with a first-time catheter ablation for AF (Jan. 1st 2010-Dec. 31st 2018) from the Danish National Ablation Registry, and eligible for one year of follow-up. Patient comorbidities and concomitant pharmacotherapy were identified using Danish nationwide registries. The patients’ Hospital Frailty Risk Score was calculated using diagnosis codes, and patients were grouped according to cut points of low (&amp;lt;5), intermediate (5-10), and high-risk (&amp;gt;10) frailty. Multivariable Cox proportional-hazards analyses were performed for comparison of associated factors for the risk of recurrence of AF during one year of follow-up after a 3-month blanking period. McNemars test was used for comparison of AF hospital admission rates before and after catheter ablation. Results Among 3,638 patients treated with first-time catheter ablation for AF (median age 62.4 years [Q1,Q3=55.1,68.5 years], 72.8% male), 89.0% had low-risk frailty, 9.4% had intermediate-risk frailty and 1.6% had high-risk frailty. At one year follow-up, 546 (15.0%) patients had recurrence of AF (hospital admission with AF or treatment with electrical cardioversion). Both intermediate-risk frailty patients (HR 1.56, CI: 1.22-2.00, p&amp;lt;0.001) and high-risk frailty patients (HR 2.13, CI: 1.30-3.49, p=0.003) had a significantly increased risk of recurrence of AF during one year of follow-up compared with patients with a low-risk frailty score. All patients across frailty groups had a 5-fold decrease in AF hospital admissions in the year after catheter ablation (15%) compared with the year before (68%) (p&amp;lt;0.001). Patients with high-risk frailty had a more than 3-fold reduction of AF hospital admissions in the year after catheter ablation (28%) compared with the year before (88%) (p&amp;lt;0.001) (Figure 1). During one year follow-up, 35 patients (1.0%) died. Conclusion Patients with high-risk frailty had a 3-fold decrease while all patients across frailty groups had a 5-fold decrease in AF hospital admissions in the year after catheter ablation compared with the year before. Thus, indicating a lower symptom burden after catheter ablation. Nevertheless, intermediate-risk and high-risk frailty was associated with significantly higher recurrence rates of AF one year after first-time catheter ablation for AF compared with low-risk frailty patients. Patient frailty should be considered when selecting patients eligible for ablation in order to improve patient outcomes.

Additional ablation to pulmonary vein isolation for persistent atrial fibrillation does not reduce recurrence

Abstract Introduction Treatment with catheter ablation (CA) as rhythm control is increasingly used in atrial fibrillation (AF). Pulmonary vein isolation (PVI) alone is less effective in patients with persistent AF (peAF) compared to patients with paroxysmal AF (PAF). Strategies and methods to optimize outcome for peAF is still an ongoing challenge. Additional ablation to pulmonary vein isolation (PVI plus) compared to PVI alone has so far shown conflicting evidence and has yet to be tested in a large unselected, real-life population with longtime follow-up. Purpose To examine AF recurrence by PVI or PVI plus for CA for peAF. Method This nationwide retrospective registry study was conducted using large real-life data from Danish mandatory registries. All patients above 18 years of age, that underwent first-time CA for peAF from January 1st 2010 to December 31st 2018, were identified and included at the date of ablation. Exposure of interest was CA, and patients were stratified into PVI or PVI plus. PVI plus was defined as either roofline, mitral linear ablation, posterior wall isolation (PWI), complex fractionated atrial electrograms (CFAE) or ganglionated plexi ablation (GP). Primary endpoint was recurrent AF after a 3-months blanking period, defined by a composite endpoint of first-reached endpoint of either use of antiarrhythmic drugs (AAD), AF-admission, electrical cardioversions or AF re-ablation. 5-year risk of recurrent AF was examined by the Aalen-Johansen estimator, taking the competing risk of death into account. The relative rates of recurrent AF by ablation strategy (PVI or PVI plus) were examined by Cox proportional models using PVI as reference. The analysis was adjusted for clinically important baseline characteristics including age, sex, diagnosis-to-ablation time, procedural year, body mass index, size of left atrium, heart failure, ischemic heart disease, chronic obstructive pulmonary disease, chronic kidney disease, hypertension and diabetes. Results The study cohort consisted of 2.444 patients with peAF undergoing first-time CA, of which 2.069 received PVI and 375 received PVI plus. Median age was 63 for the PVI group and 64 for the PVI plus group. The PVI plus group had longer diagnosis-to-ablation-time and enlarged left atrium compared to the PVI group. 5-year cumulative incidence of recurrent AF was 55% for the PVI group and 71% for the PVI plus group in the unadjusted analysis (Figure 1). The relative risk of recurrent AF showed hazard ratio of 1.11 (95% CI: 0.95-1.29) for the PVI plus group compared to the PVI group (Figure 2). Conclusion Strategies to reduce AF recurrences after CA for peAF is an ongoing challenge. This study did not find any significant reduction in recurrence of AF using PVI plus strategy compared to PVI alone. The increased absolute risk of AF recurrence in the PVI plus group is most likely accounted for by longer diagnosis-to-ablation-time and enlarged left atrium compared to the PVI group.Figure 1Figure 2