Symptomatic Persistent Atrial Fibrillation Research Articles

Pulmonary Vein Isolation or Pace and Ablate in Elderly Patients With Persistent Atrial Fibrillation (ABLATE Versus PACE)—Rationale, Methods, and Design

Age is a major risk-factor for atrial fibrillation (AF) and associated hospitalisations. With increasing emphasis on rhythm control, pulmonary vein isolation (PVI) is often suggested, even to elderly patients (≥ 75 years of age). Efficacy of PVI aiming at rhythm control is limited in persistent AF. Pacemaker implantation with atrioventricular node (AVN) ablation may represent a reasonable alternative, with the aim of controlling symptoms and improving quality of life in elderly patients. In this investigator-initiated, randomised, multicentre trial, we test the hypothesis that pacemaker implantation and AVN ablation provides superior symptom control over PVI in elderly patients with symptomatic persistent AF, without any increase in adverse event profile. In the ABLATE Versus PACE (NCT 04906668) prospective open-label superiority trial, 196 elderly patients with normal ejection fraction and symptomatic persistent AF despite guideline-indicated medical therapy will be randomised to either cryoballoon PVI (ABLATE) or dual-chamber pacemaker implantation with subsequent AVN ablation (PACE), and followed for a minimum of 12 months. The primary efficacy outcome is a composite end point of rehospitalisation for atrial arrhythmia or cardiac decompensation/heart failure, (outpatient) electrical cardioversion, or upgrade to cardiac resynchronisation therapy owing to worsening of left ventricular ejection fraction to ≤ 35%. Secondary end points include death from any cause, stroke, quality of life, and procedure-related complications. Sample size is designed to achieve 80% power for the primary end point (2-tailed alpha of 5%). ABLATE Versus PACE will determine whether pacemaker implantation and AVN ablation can improve symptom-control in elderly patients with persistent AF over PVI without increasing safety end points.

A genetic polymorphism on chromosome 4q25 (rs17570669_T) may predict atrial fibrillation recurrence after successful electrical cardioversion

Abstract Background Direct current electrical cardioversion (DCCV), is an effective treatment method in patients with symptomatic persistent atrial fibrillation (AF). However, AF recurrence may occur following successful DCCV in nearly half of the patients. There is not enough data investigating the association between single nucleotide polymorphisms (SNP) and AF recurrence after DCCV. Purpose We aimed to investigate whether 11 SNPs previously associated with AF (rs2200733, rs10033464, rs6838973, rs3853445 and rs17570669 SNPs in PITX2 gene; rs2106261 SNP in ZFHX3 gene; rs751141 SNP on chromosome 8q21; rs3807989 SNP in CAV1 gene; rs10570248 SNP in TBX5 gene; rs1800469 SNP in TGF-1 gene; and rs6795970 SNP in SCN10A gene) were predictive for recurrence after successful DCCV in patients with persistent AF in Turkish society. Methods We included 75 patients with sinus rhythm after direct current electrical cardioversion (DCCV). Baseline clinical features and 11 AF-related SNPs were compared between patients with and without AF recurrence during the follow-up. The association between SNPs and AF recurrence was evaluated with the additive model (wild type vs heterozygous variant vs homozygous variant), the dominant model (wild type/heterozygous vs homozygous variant), and the recessive model (wild type vs heterozygous variant/homozygous variant). Results The mean age of the patients was 61.9 ± 11.5 years. At a mean follow-up of 17.0 (11.0-25.0) months, 38 patients (50.7%) developed AF recurrence. The frequency of the female gender was higher (55.3% vs. 32.4%), AF duration before DCCV was longer [9.2 (5.5-11.6) vs 5.0 (2.7-11.0) months], and left atrial volume index before DCCV was higher (43.6 ± 8.8 ml/m2 vs. 38.2 ± 12.9 ml/m2) in patients who developed AF recurrence than those without it (p=0.046, 0.029 and 0.036, respectively) (Figure 1a). In the additive model, a SNP at the PITX2 gene (rs17570669_T: OR 9.00, 95% CI 1.28-63.02, p=0.027) and a SNP at the ZFHX3 gene (rs2106261_T: OR 8.96, 95% CI 1.03-77.66, p=0.047) were significantly associated with AF recurrence. Female gender (HR: 1.99, 95% CI: 1.05-3.79, p=0.035) and the rs17570669_T SNP (HR: 4.16, 95% CI: 1.22-14.11, p=0.022) were predictors for AF recurrence in univariate analysis. A multivariate Cox regression analysis showed that the rs17570669_T SNP was an independent predictor of AF recurrence following successful DCCV in the additive model (HR: 3.59, 95% CI: 1.05-12.21, p=0.04) (Figure 1b). A Kaplan-Meier curve showed that AF-free survival was significantly lower in patients who had rs17570669_T SNP in the additive model (Figure 2). Conclusion A SNP at the PITX2 locus (rs17570669_T) may predict AF recurrence after successful DCCV in patients with persistent AF in Turkish society. Such individuals may be closely monitored for the development of AF recurrence after DCCV. In addition, reversible risk factors associated with AF recurrence may be more tightly controlled in such patients.Baseline features and Cox analysisKaplan-Meier curve

Catheter ablation of persistent atrial fibrillation: circumferential pulmonary vein ablation with or without a linear lesion at the left atrial roof for (12-year follow-up)

Abstract Background Catheter ablation has become the first line of therapy in patients with symptomatic, recurrent, drug-refractory atrial fibrillation. Circumferential pulmonary vein ablation is still the standard approach in these patients. However, the results are not very favourable and more complex ablation strategies are the subject of current controversy. Therefore, we have evaluated the effect of an additional linear lesion at the roof of the left atrium on the long-term outcome. Methods A total of 300 patients (155 men, 145 women; mean age 72 years (SD ± 18 years)) with symptomatic persistent atrial fibrillation underwent a circumferential pulmonary vein ablation procedure in combination with an additional linear lesion at the roof of the left atrium (group A). After discharge, patients were scheduled for repeated visits at the arrhythmia clinic at 1, 3, 6, 12, 24, 36, 48, 60, 72, 84, 96, 102, 108, 120, 132, 138 and 144 months after the ablation procedure. The long-term follow-up data was compared to 300 patients who underwent circumferential pulmonary vein ablation without an additional linear lesion at the roof of the left atrium (group B). Results The ablation procedure could be performed as planned in all patients. Sixfty-six out of 300 patients (22.0 %) in group A and 69 out of 300 patients (23.0 %) in group B experienced an arrhythmia recurrence within the first 3 months after ablation requiring an electrical cardioversion. At 144-month follow-up, analysis of a 168-hour ECG recording revealed no evidence for an arrhythmia recurrence in 171/300 patients (57.0 %) in group A and in 141/300 patients (47.0 %) in group B. In 87/300 patients (29.0 %) in group A and 78/300 patients (26.0 %) in group B, only short episodes of paroxysmal atrial fibrillation were documented. In 42 patients (14.0 %) in group A, a recurrence of persistent atrial fibrillation (> 48 hours) was revealed by the long-term recordings (group B: 81 patients (27.0 %)). The lower arrhythmia recurrence rate in group A was partially due to a lower incidence of atypical atrial flutter after catheter ablation. The rate of repeat ablation procedures was significantly lower in group A than in group B. There were no major complications. Conclusions Catheter ablation of persistent atrial fibrillation comprising a circumferential pulmonary vein ablation and an additional linear lesion at the roof of the left atrium provides more favourable results than circumferential pulmonary vein ablation alone. The effect is more pronounced during long-term than during short-term follow-up.

A Case of Presumptive Marshall Bundle Conduction Between the Left Atrium and Left Superior Pulmonary Vein During Box Isolation

A 65-year-old man with symptomatic persistent atrial fibrillation was referred for initial radiofrequency catheter ablation. He underwent box isolation to simultaneously isolate all four pulmonary veins (PVs) and the posterior wall of the left atrium (LA). During the box isolation with a double lasso catheter positioned in both the left superior and right superior PVs, the atrial fibrillation terminated spontaneously. After the box lesion set was created, conduction was still observed between the LA and PVs. After an additional radiofrequency energy delivery to the bottom line of the box lesion, the activation sequence of the PVs became uniform during sinus rhythm and pacing from the coronary sinus (CS), indicating that only one more conduction pathway was present. The 3-dimensional map revealed that the earliest activation site within the box lesion was located in the anterior aspect of the left superior PV during pacing from the CS, whereas that of the LA during pacing from the superior right PV within the box was on the posterolateral LA wall below the left inferior When a 2 Fr electrode catheter was inserted into the vein of Marshall (VOM) and paced within the BOX, VOM potentials preceded CS potentials. When the left superior PV anterior wall, the earliest site of excitation within the box, was energized, simultaneous posterior pulmonary vein wall isolation was completed. We experienced a case in which Marshall bundle conduction between the left atrium and the pulmonary vein was assumed.

Adolescent Persistent Atrial Fibrillation Concomitant with Pectus Excavatum.

A 19-year-old man with pectus excavatum developed symptomatic persistent atrial fibrillation (AF). He had no remarkable medical history or comorbidities and had not exercised intensely during childhood. Electrical cardioversion and pre-treatment with amiodarone for two months failed to maintain sinus rhythm. Computed tomography before ablation revealed compression of the right and left atria between the sternal bone and vertebral bodies. Voltage mapping revealed that the right and left atrial voltages were preserved within the normal limit. However, radiofrequency catheter ablation successfully eliminated recurrent persistent AF. No recurrence was observed during eight months of follow-up.

Left atrial strain significance in prediction of early atrial fibrillation recurrence after cardioversion and ablation

Abstract Funding Acknowledgements Type of funding sources: None. Introduction The fibrosis of the LA, which is characteristic of AF, causes mechanical dysfunction of the LA and may also be present in patients without LA enlargement. LA strain represents a surrogate marker of this mechanical dysfunction. Early detection of LA dysfunction may be crucial in identifying patients who are more likely to experience AF recurrence following cardioversion and ablation. Before cardioversion and ablation, the probability of AF recurrence might be predicted, which could lead to better patient selection, an individualized therapeutic strategy with reduced risk and focused follow-up. Purpose The aim of this study was to evaluate the additional predictive value of LA function assessed by using strain echocardiography for early AF recurrence after cardioversion and ablation. Methods 94 patients diagnosed with symptomatic persistent atrial fibrillation (EHRA symptom score ≥3 (mean age 59.4 ± 12.2 years, 58% male, 42%female), preserved LV ejection fraction were prospectively analyzed. In 39 (41,5%) patients pharmacological cardioversion was done after saturation with antiarhythmic drugs,in 27 (28,7%) patients planed electrical cardioversion was done after medical saturation with antiarrhythmic drugs and failure of pharmacological cardioversion, and in 28 (29,8%) patients planed RF ablation was performed. Complete echocardiography evaluation including strain and volume index LA was performed before cardioversion and ablation. The rhythm evaluation was done in the first month after cardioversion and RF ablation (35±5 days). The primary endpoint was persistent AF recurrence. Results 29 (30,8%) patients had AF recurrence in the overall study population, independently of duration of AF or method of rhythm control. Peak atrial longitudinal strain (PALS) ≤15% had the highest incremental predictive value for AF recurrence (HR =8.42, 95% CI: 3.17–25.12, p < 0.001). In patients with non-dilated LA, PALS≤15% remained an independent predictor of AF recurrence (HR = 5.32, 95% CI: 1.77–17.42, p = 0.005). Conclusion This study shown that, in addition to LA dilatation, LA function as determined by PALS can provide a prognostic value for early AF recurrence after cardioversion or ablation. PALS also predicted AF recurrence in patients with nondilated LA. These findings highlight the additional prognostic usefulness of LA strain and recommend its implementation in the systematic assessment of AF patients prior to the choice of rhythm/rate control.

A novel stepwise approach incorporating ethanol infusion in the vein of Marshall for the ablation of persistent atrial fibrillation.

Apart from pulmonary vein isolation (PVI), several step-by-step procedures that aim to modify left atrial substrate have been proposed for the ablation of persistent atrial fibrillation (AF), yet the optimal strategy remains elusive. There are cumulative data suggesting an incremental benefit of adding vein of Marshall (VOM) ethanol infusion to PVI in patients with persistent AF. We sought to evaluate the feasibility and efficacy of a novel stepwise ablation approach, incorporating a VOM alcoholization step, for persistent AF. In this single-center study, we prospectively enrolled 66 consecutive patients with symptomatic persistent AF and failure of at least one antiarrhythmic drug (ADD). The ablation procedure consisted of (i) PVI, (ii) left atrial segmentation with VOM ethanol infusion and the deployment of linear radiofrequency lesions across the roof and the mitral isthmus and (iii) electrogram-based ablation of dispersion zones. The first two steps were performed in all patients, whereas the third step was carried out only in those still in AF at the end of the second step. Atrial tachycardias during the procedure were mapped and ablated. At the end of the procedure, cavotricuspid isthmus ablation was additionally performed in all patients. The primary endpoint was 12-month freedom from AF and atrial tachycardia after a single procedure and an initial three-month blanking period. Total procedure time was 153 ± 38.5 min. Fluoroscopy time was 16 ± 6.5 min and the radiofrequency ablation time was 26.14 ± 0.26 min. The primary endpoint occurred in 54 patients (82%). At 12 months, 65% of patients were off any AAD. In the univariate Cox regression analysis, left ventricular ejection fraction < 40% was the only predictor of arrhythmia recurrence (HR 3.56; 95% CI, 1.04-12.19; p = 0.04). One patient developed a pericardial tamponade and another a minor groin hematoma. A novel stepwise approach, including a step of ethanol infusion in the VOM, is feasible, safe and provides a high rate of sinus rhythm maintenance at 12 months in patients with persistent AF.

PO-02-098 CHARACTERISTICS OF PATIENTS CHOSEN FOR CATHETER ABLATION AS AN INITIAL RHYTHM CONTROL STRATEGY IN SYMPTOMATIC PERSISTENT ATRIAL FIBRILLATION: AN ANALYSIS OF THE REAL-AF REGISTRY

According to the 2017 HRS guidelines, catheter ablation (CA) for symptomatic persistent atrial fibrillation (PSAPF) is reasonable whether the patient is currently taking antiarrhythmic drugs (AADs) or has not started them. It is unclear what drives decision-making regarding CA versus AADs as first-line therapy for rhythm control in atrial fibrillation. We aimed to analyze differences in patients who are chosen for first-line CA compared with those who receive CA after a trial of AADs. To describe differential characteristics in patients undergoing first-line CA versus those who started AAD for symptomatic PsAF and ended up requiring ablation therapy. Based on The Real-world Experience of Catheter Ablation for the Treatment of Symptomatic Paroxysmal and PsAF Using Novel Contact Force Technologies (Real-AF) registry as a prospective, observational, multicenter registry of patients undergoing radiofrequency (RF) ablation. A total of 1,464 patients with symptomatic PsAF who underwent de novo ablation were identified and characterized, regardless of whether they had initiated AAD. First-line CA for rhythm control was defined as patients undergoing CA who had never been prescribed antiarrhythmic medication. First-line CA was performed on 593 patients (40.5%), while first-line AAD was used in 871 patients (59.5%). At the time of ablation, 76.2% of patients in the AAD arm were still taking them, specifically amiodarone was the most prescribed antiarrhythmic (39.8%), followed by flecainide (14.1%). Likewise, patients who received first-line CA were significantly more likely to be male, younger, have a lower BMI, minor CHADS2Vasc and HASBLED scores, reduced prevalence of renal disease or diabetes, and a higher baseline LVEF (Table 1). In addition, patients who received first-line CA were closer in time to their initial diagnosis, were much less likely to have undergone prior cardioversion, and had a lower incidence of recent PsAF related hospitalization (Table 1). There were no differences in baseline left atrial parameters on imaging or electroanatomic mapping. Patients offered first-line CA for rhythm control as opposed to AAD tended to be healthier and in an earlier course of PsAF disorder. Interestingly, despite these baseline differences , there were no significant divergences in left atrial size or voltage.

His-Purkinje conduction system pacing combined with atrioventricular node ablation improves quality of life in older patients with persistent atrial fibrillation refractory to multiple ablation procedures.

Recurrence of atrial fibrillation (AF) is common in patients with persistent AF even after multiple ablation procedures. His-Purkinje conduction system pacing (HPCSP) combined with atrioventricular node ablation (AVNA) is effective in managing patients with AF and heart failure. This study aimed to determine whether HPCSP combined with AVNA can improve quality of life and alleviate symptoms in older patients with symptomatic persistent AF refractory to multiple ablation procedures, as well as evaluate the feasibility and safety of this therapy. Older patients (≥ 65 years) with symptomatic persistent AF refractory to at least two ablation procedures were treated with combined HPCSP and AVNA. The success rates and complications were recorded. Pacing parameters, European Heart Rhythm Association (EHRA) scores, and Atrial Fibrillation Effect on Quality-of-Life (AFEQT) scores obtained perioperatively were compared with those recorded at the 6-month follow-up examination. Thirty-one patients were enrolled; of those, only thirty patients were eventually treated with AVNA because one patient developed a complete atrioventricular block following the withdrawal of the His bundle pacing lead. The success rates were 100% for HPCSP (22 cases with His bundle pacing, and 9 cases with left bundle branch pacing) and 93.3% (28/30) for AVNA, respectively. By the 6-month follow-up examination, EHRA scores improved significantly (3.00 ± 0.73 vs. 2.44 ± 0.63, P = 0.014) and AFEQT scores increased markedly (49.6 ± 20.6 vs. 70.9 ± 14.0, P = 0.001). No severe complications developed. When used in older patients with symptomatic persistent AF refractory to multiple ablation procedures, HPCSP combined with AVNA significantly alleviated symptoms and improved quality of life during short-term follow-up. This therapy was proved to be safe and effective in this patient population.

His-Purkinje conduction system pacing and atrioventricular node ablation in treatment of persistent atrial fibrillation refractory to multiple ablation procedures: A case report

In patients with symptomatic atrial fibrillation refractory to optimal medical therapy, atrioventricular node ablation followed by permanent pacemaker implantation is an effective treatment option. A 66-year-old woman with symptomatic persistent atrial fibrillation refractory to multiple ablation procedures was referred to our institution. After optimal drug therapy, the patient still had obvious symptoms. Sequential His-Purkinje conduction system pacing and atrioventricular node ablation were performed. Left bundle branch pacing was used as a backup pacing method if thresholds of His bundle pacing were too high or loss of His bundle capture occurred in the follow-up. At the 6-month follow-up, the European Heart Rhythm Association classification for AF was improved, the score of the Atrial Fibrillation Effect on Quality of Life was enhanced, and the 6-Minute Walk Test was ameliorated. The present case was subjected to His-Purkinje conduction system pacing in combination with atrioventricular node ablation as treatment for a symptomatic persistent atrial fibrillation refractory to multiple ablation procedures, and this procedure alleviated symptoms and improved the quality of life in a short-term follow-up.

Hybrid epicardial-endocardial ablation for long-standing persistent atrial fibrillation: A subanalysis of the CONVERGE Trial

Favorable clinical outcomes are difficult to achieve in long-standing persistent atrial fibrillation (LSPAF) with catheter ablation (CA). The CONVERGE (Convergence of Epicardial and Endocardial Ablation for the Treatment of Symptomatic Persistent Atrial FIbrillation) trial evaluated the effectiveness of hybrid convergent (HC) ablation vs endocardial CA. The study sought to evaluate the safety and effectiveness of HC vs CA in the LSPAF subgroup from the CONVERGE trial. The CONVERGE trial was a prospective, multicenter, randomized trial that enrolled 153 patients at 27 sites. A post hoc analysis was performed on LSPAF patients. The primary effectiveness was freedom from atrial arrhythmias off new or increased dose of previously failed or intolerant antiarrhythmic drugs (AADs) through 12 months. The primary safety endpoint was major adverse event incidence through 30 days with HC. Key secondary effectiveness measures included (1) percent of patients achieving ≥90% AF burden reduction vs baseline and (2) AF freedom. Sixty-five patients (42.5% of total enrollment) had LSPAF; 38 in HC and 27 in CA. Primary effectiveness was 65.8% (95% confidence interval [CI] 50.7%-80.9%) with HC vs 37.0% (95% CI 5.1%-52.4%) with CA (P = .022). Through 18 months, these rates were 60.5% (95% CI 50.0%-76.1%) with HC vs 25.9% (95% CI 9.4%-42.5%) with CA (P = .006). Secondary effectiveness rates were higher than CA with HC at 12 and 18 months. Freedom from atrial arrhythmias off AADs was 52.6% (95% CI 36.8%-68.5%) and 47.4% (95% CI 31.5%-63.2%) with HC at 12 and 18months vs 25.9% (95% CI 9.4%-42.5%) and 22.2% (95% CI 6.5%-37.9%) with CA, respectively (12 months: P = .031; 18 months: P = .038). Three (7.9%) major adverse events occurred within 30 days of HC. Post hoc analysis demonstrated effectiveness and acceptable safety of HC compared with CA in LSPAF.

Economic Evaluation of Contact Force Catheter Ablation for Persistent Atrial Fibrillation in the United States.

Atrial fibrillation (AF) is the most prevalent cardiac arrhythmia, and it increases the risk of stroke, heart failure, and other cardiac complications. Catheter ablation is well-established as a treatment for paroxysmal AF, and the recent PRECEPT (Prospective Review of the Safety and Effectiveness of the THERMOCOOL SMARTTOUCH SF Catheter Evaluated for Treating Symptomatic Persistent AF) clinical trial resulted in the catheter gaining approval for the treatment of persistent AF in the United States. To construct an economic simulation model, based on the results of the PRECEPT trial, to monetize the impact of radiofrequency catheter ablation (RFCA) compared with medical therapy (MT). Cost-offset and break-even analyses were performed to assess the economic impact of RFCA vs MT for adult persistent AF patients. Three perspectives were considered: commercial payers, Medicare, and self-insured employers. A cohort-level decision tree model was developed and validated in TreeAge Pro 2019. Sensitivity analyses were performed to determine the robustness of findings. For all 3 types of payer, RFCA had a higher initial cost compared with MT. However, reductions in health care utilization after ablation, driven by decreased cardiovascular hospitalizations, led to an annual cost offset of between $5037 and $8402 after the first year. Projecting this forward resulted in an estimated cost break-even after 5.9, 4.2, and 5.1 years for commercial payers, Medicare, and self-insured employers, respectively. In addition to providing clinical benefits, RFCA may be a valuable economic investment for U.S. payers, substantially reducing utilization after the first year.

Mid-term success rate of single stage hybrid ablation of persistent and long-term persistent atrial fibrillation.

Single stage thoracoscopic radiofrequency ablation (RFA) is a treatment method for persistent and long-term persistent atrial fibrillation (AF) offering the possibility for patients otherwise inconsolable by conventional catheter RFA. We present a pilot group of patients after the introduction of the new method at our clinical center. Patients group: A total of 52 patients aged 61.82 ± 9.7 years underwent single stage hybrid ablation (thoracoscopic isolation of pulmonary veins and box lesion followed by catheter verification of the surgical procedure effectivness) for symptomatic persistent and long-term persistent AF with significantly dilated left atrium 57.9 ± 11.0mm in the period September 2016-March 2019. The median duration of the procedure was 232 minutes and the median duration of hospitalization was 10 days. At discharge, 52 patients (100%) had sinus rhythm. 48 of 52 patients (92.3%) had a 6-month follow-up. 41 of 48 (85.4%) and 38 of 44 (86.4%) of patients were AF free at 3-month and 6-month follow-up, respectively. Acute complications were: one left atrial perforation resolved successfully by suture and one transient ischaemic attack without permanent sequelae. Late complications involved one massive pulmonary embolization and an atrioesophageal fistula. There was no periprocedural myocardial infarction or stroke with permanent sequelae. Hybrid thoracoscopic-catheter ablation performed during one procedure is an effective and relatively safe mini-invasive method of treatment for long-term persistent atrial fibrillation.

Cryoballoon versus radiofrequency catheter ablation: insights from Norwegian randomized study of persistent atrial fibrillation (NO-PERSAF study)

Abstract Funding Acknowledgements Type of funding sources: Foundation. Main funding source(s): Helse Vest, Norway (LBS) Background Pulmonary vein isolation (PVI) is still regarded as a cornerstone for treatment of persistent atrial fibrillation (AF). Both radiofrequency ablation (RFA) and cryoballoon ablation (CBA) are frequently employed to achieve PVI. Purpose This randomized study aimed to evaluate the effectiveness of PVI performed with CBA in comparison with RFA in patients with persistent AF. Methods A total of 101 patients with symptomatic persistent AF were enrolled and randomized (1:1) to CBA or RFA groups and followed up for 12 months. The primary endpoint was any documented recurrent atrial tachyarrhythmia (ATA) lasting longer than 30 s following a 3-month blanking period. Secondary endpoints were procedure-related complications, procedure and ablation duration, and fluoroscopy time. The ATA-free survival curves were estimated by Kaplan–Meier method and analyzed by log-rank test. Results According to intention-to-treat analysis, freedom from ATA was achieved in 36 out of 52 patients in the CBA group and 30 out of 49 patients in the RFA group (69.2% vs. 61.2%, P=0.393). No difference of AF recurrence was found between the two groups (27.5% in CBA vs. 38.0% in RFA, P=0.258), and less atrial flutter recurrence was documented in the CBA group compared with the RFA group (3.9% vs. 18.0%, P=0.020). The procedure and ablation duration were significantly shorter in the CBA group (160±31 vs. 197±38 minutes, P&amp;lt;0.0001; 36.7±9.5 vs. 55.3±16.7 minutes, P&amp;lt;0.0001). There was no difference regarding fluoroscopy time (21.5±7.8 vs. 23.4±11.2 minutes, P&amp;gt;0.05). Conclusions Compared with RFA, PVI performed by CBA led to shorter procedure and ablation duration, with less atrial flutter recurrence and similar freedom from ATA at 12-month follow-up.

Durability of CLOSE-guided pulmonary vein isolation in persistent atrial fibrillation - First results from a prospective remapping study

Abstract Funding Acknowledgements Type of funding sources: None. Background The CLOSE protocol for pulmonary vein isolation (CLOSE-PVI) combines ablation index and inter-lesion distance (≤6 mm) targets. CLOSE-PVI has been shown to result in high clinical success rates. Data on durability of PVI after CLOSE-PVI mainly derive from repeat procedures in paroxysmal atrial fibrillation (AF) patients with recurrent AF. Purpose We sought to assess the incidence of pulmonary vein (PV) reconnections during a staged redo procedure performed independently of AF recurrence 6 months after CLOSE-PVI in patients with persistent AF. Methods In this prospective, single-center study, patients with symptomatic persistent AF (EHRA score &amp;gt;1) undergoing AF ablation were included. Close-PVI was performed during the index procedure. A blanking period of 3 months was applied. Seven-day Holter ECGs were performed at 3 and 6 months post ablation. All patients underwent a staged redo procedure including high-density voltage mapping of the left atrium at 6 months after the index procedure. Results Overall, 20 patients were included (median age: 68 years [IQR 63-71]; 20% women; median duration of persistent AF: 8 months [IQR 5-15]; median LAVI 45 ml/m2 [IQR 43-53]). All PVs were successfully isolated with CLOSE-PVI during the index procedure. Four patients (20%) had AF recurrence. The redo procedure was performed after a median of 6.1 months (IQR 5.6-7.3). Of 80 PVs, 71 (89%) were still isolated. No patient had a common ostium. Reconnections were observed in 3 left superior (15%), in one left inferior (5%), in one right superior (5%) and in 4 right inferior (20%) PVs. Fourteen patients (74%) had completely isolated PVs. Two of four patients with AF recurrence (50%) and 12 of 16 patients without AF recurrence (75%) had completely isolated PVs (p=0.33). Conclusions CLOSE-PVI achieves durable PVI after 6 months in the majority of patients with persistent AF. In half of persistent AF patients with recurrence after CLOSE-PVI, all PVs are still isolated. These patients may need adjunctive ablation.

Single-center outcome after ablation of atrial fibrillation using very high-power short duration pulmonary vein isolation

Abstract Funding Acknowledgements Type of funding sources: None. Background Catheter ablation of atrial fibrillation is (AF) an established second line therapy for patients with symptomatic paroxysmal (PAF) and persistent AF (persAF). Novel ablation catheters with integrated thermocouples allow fast application of radiofrequency lesions with powers up to 90W. We aimed to describe primary and secondary outcomes after very high-power short duration (vHPSD) ablation. Methods 126 consecutive patients (78 PAF, 43 persAF, 5 longstanding persistent AF) underwent pulmonary vein isolation (PVI) using the QDOT Micro Catheter (Biosense Webster) with the ablation mode QMODE+ (90W, 4s, interlesion distance ≤4mm anterior, ≤6mm posterior). Results Mean age was 62±9 years, 33% were female, median CHA2DS2-VASc Score was 2 (0, 7). Median follow up duration was 204 (14, 461) days. 30% of patients had additional ablation of typical right atrial flutter. Primary success rate to achieve pulmonary vein isolation was achieved in all patients, no catheter-related complications (e.g., charring, steam pop) occurred. First pass isolation of all 4 PVs was achieved in 48% of patients, re-ablations were necessary in the carina regions (right: 37% of cases, left: 29%) and ridge (14%). Median procedure for PVI only were 102 (45-210) minutes. Arrhythmia-free survival was 79,6% (see Figure 1). Eight patients underwent re-do procedures during follow-up showing most commonly showing gaps in the right inferior PV (63%) and ridge (50%). Conclusion Very high-power short duration ablation allows safe and quick pulmonary vein isolation. However, first pass isolation rate is low due to gaps in the carina regions. Arrhythmia-free survival is comparable to other pulmonary vein isolation techniques. Figure 1: Left panel: Sample image of a vHPSD-PVI, posterior view of the left atrium. Right panel: Single procedure arrhythmia-free survival after vHPSD-PVI.

The hybrid convergent procedure for persistent and long-standing persistent atrial fibrillation from an electrophysiologist's perspective.

In atrial fibrillation (AF), the pulmonary veins (PVs) are central to arrhythmogenicity and are targeted by PV isolation (PVI). As AF progresses, triggers become more prevalent in non-PV areas including the left atrial posterior wall (LAPW). Reported benefits of LAPW isolation in Cox-maze IV led to exploration of ablation strategies using endocardial catheters. However, no single approach to endocardial LAPW isolation exists. Relative success in comparison to PVI alone has been mixed. The hybrid convergent procedure was developed to combine minimally invasive surgical and electrophysiology techniques to accomplish effective PVI and LAPW isolation. Epicardial LAPW isolation is performed by a cardiothoracic surgeon followed by endocardial ablation by an electrophysiologist who ensures PVI completion and targets any remaining gaps. Safety and effectiveness of hybrid convergent were evaluated in the prospective, multicenter, randomized controlled trial, Convergence of Epicardial and Endocardial Ablation for the Treatment of Symptomatic Persistent AF (CONVERGE). CONVERGE compared the effectiveness of the hybrid convergent procedure to endocardial catheter ablation for treatment of drug-refractory persistent and long-standing persistent AF and demonstrated primary effectiveness of higher freedom from atrial arrhythmias absent new/increased dose previously failed/intolerant antiarrhythmic drugs through 12 months compared to endocardial catheter ablation. Greater freedom from AF and proportion of patients experiencing ≥90% burden reduction with hybrid convergent ablation were seen through 18 months of follow-up. Improved electrophysiology lab efficiency was demonstrated by the reduction in endocardial ablation time with addition of epicardial ablation. This multidisciplinary heart team procedure may improve outcomes in difficult-to-treat patients with advanced AF.

Local inhomogeneous conduction and non-uniform anisotropism in a normal voltage atrial map.

A patient with symptomatic persistent atrial fibrillation and recurrences after pulmonary vein isolation (PVI)underwent a second ablation procedure. The PVs were found isolated and the left atrial substrate tissue wasmapped. During sinus rhythm, the voltage map resulted in a normal range (>0,5mV) while a map of EGMsdurations revealed an area presenting prolonged EGMs (>45 ms) in the anterior region. The activation map of thisarea demonstrated abnormal conduction and a non-uniform anisotropism when compared with areas in whichEGM's normal durations were recorded. The EGMs duration map may offer additional clinical information on theareas presenting abnormal conduction predisposing arrhythmias maintenance in patients suffering from persistentatrial fibrillation.

Electrical Cardioversion for Persistent Atrial Fibrillation in the Era of Catheter Ablation: A Real-world Observational Study

Background: Electrical cardioversion (ECV) is frequently performed to treat persistent atrial fibrillation (AF). Although several large trials have suggested that rate control in AF may be non-inferior to rhythm-based strategies, individual patients may have better outcomes in terms of quality of life if sinus rhythm (SR) is achieved and maintained. This real-world, retrospective, observational study aimed to define the success rate and role of ECV in the management of persistent AF in the era of catheter ablation. Methods: All patients who underwent ECV for symptomatic persistent AF at our institution between January 2014 and August 2019 were analysed. Clinical and echocardiographic baseline characteristics were used to identify independent predictors for AF recurrence at 12 and 24 months using a Cox multivariate model. Results: We identified 1,028 consecutive patients with symptomatic persistent AF, 319 of whom were subsequently excluded from the study because they either spontaneously reverted to SR prior to ECV or declined ECV. We evaluated 701 patients (mean age 71 ± 10.8 years, male 70.2%). Acute success was achieved in 96.8% of patients. SR at 12 and 24 months was seen in 26.6% and 14.3% of patients (p&lt;0.0001), respectively. SR at 12 months was seen in 20.4% of patients with a left atrium (LA) diameter of ≤4 cm and in 6.2% of patients with an LA diameter of &gt;4 cm (p&lt;0.0001). At 24 months, SR was seen in 11.5% of patients with a LA diameter of ≤4 cm and in 2.8% with a diameter of &gt;4 cm (p&lt;0.0001). Predictors of SR at 12 months on univariate analysis were normal left ventricular systolic function and mild left ventricular systolic impairment (odds ratio [OR] 1.61, 95% confidence interval [CI] 1.08–2.45, p=0.021 and OR 0.5, 95% CI 0.24–0.94, p=0.043, respectively). In addition, flecainide and sotalol therapy improved the chances of SR at 12 months (OR 2.87, 95% CI 1.16–7.12, p=0.021 and OR 2.25, 95% CI 0.98–5.05, p=0.049, respectively). Multivariate analysis revealed no further positive predictors for SR maintenance in 24 months. Conclusion: ECV was not an effective long-term strategy for the maintenance of SR.

Cryoballoon vs. radiofrequency catheter ablation: insights from NOrwegian randomized study of PERSistent Atrial Fibrillation (NO-PERSAF study).

AimsPulmonary vein isolation (PVI) is still regarded as a cornerstone for treatment of persistent atrial fibrillation (AF). This study evaluated the effectiveness of PVI performed with cryoballoon ablation (CBA) in comparison with radiofrequency ablation (RFA) in patients with persistent AF.Methods and results A total of 101 patients with symptomatic persistent AF were enrolled and randomized (1:1) to CBA or RFA groups and followed up for 12 months. The primary endpoint was any documented recurrent atrial tachyarrhythmia (ATA) lasting longer than 30 s following a 3-month blanking period. Secondary endpoints were procedure-related complications, procedure and ablation duration, and fluoroscopy time. The ATA-free survival curves were estimated by Kaplan–Meier method and analysed by the log-rank test. According to intention-to-treat analysis, freedom from ATA was achieved in 36 out of 52 patients in the CBA group and 30 out of 49 patients in the RFA group (69.2% vs. 61.2%, P = 0.393). No difference in AF recurrence was found between the two groups (27.5% in CBA vs. 38.0% in RFA, P = 0.258), and less atrial flutter recurrence was documented in the CBA group compared with the RFA group (3.9% vs. 18.0%, P = 0.020). The procedure and ablation duration were significantly shorter in the CBA group (160 ± 31 vs. 197 ± 38 min, P < 0.0001; 36.7 ± 9.5 vs. 55.3 ± 16.7 min, P < 0.0001). There was no difference regarding fluoroscopy time (21.5 ± 7.8 vs. 23.4 ± 11.2 min, P > 0.05).Conclusion Compared with RFA, PVI performed by CBA led to shorter procedure and ablation duration, with less atrial flutter recurrence and similar freedom from ATA at 12-month follow-up.