Polar X or Arctic Front cryoballoon ablation for persistent atrial fibrillation

Research Needs and Priorities for Catheter Ablation of Atrial Fibrillation

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Left atrial appendage (LAA) electric isolation is reported to improve persistent atrial fibrillation (AF) ablation outcomes. However, loss of LAA mechanical function may increase thromboembolic risk. Concomitant LAA electric isolation and occlusion as part of conventional AF ablation has never been tested in humans. We therefore evaluated the feasibility, safety, and efficacy of LAA electric isolation and occlusion in patients undergoing long-standing persistent AF ablation. Patients with long-standing persistent AF (age, 68±7 years; left atrium diameter, 46±3 mm; and AF duration, 25±15 months) underwent AF ablation, LAA electric isolation, and occlusion. Outcomes were compared with a balanced (1:2 ratio) control group who had AF ablation alone. Among 22 patients who underwent ablation, LAA electric isolation was possible in 20. Intraprocedural LAA reconnection occurred in 17 of 20 (85%) patients, predominantly at anterior and superior locations. All were reisolated. LAA occlusion was successful in all 20 patients. There were no major periprocedural complications. Imaging at 45 days and 9 months confirmed satisfactory device position and excluded pericardial effusion. One of twenty (5%) patients had a gap of ≥5 mm requiring anticoagulation. Nineteen of twenty (95%) patients stopped warfarin at 3 months. Without antiarrhythmic drugs, freedom from AF at 12 months after a single procedure was significantly higher in the study group (19/20, 95%) than in the control group (25/40, 63%), P=0.036. Freedom from atrial arrhythmias was demonstrated in 12 of 20 (60%) and 18 of 20 (90%) patients after 1 and ≤2 procedures (mean, 1.3), respectively. Persistent AF ablation, LAA electric isolation, and mechanical occlusion can be performed concomitantly. This technique may improve the success of persistent AF ablation while obviating the need for chronic anticoagulation. URL: https://clinicaltrials.gov. Unique identifier: NCT02028130.

Clinical outcomes of catheter ablation for persistent atrial fibrillation (AF) remain discouraging. This meta‑analysis aimed to compare cryoballoon ablation (CBA) with radiofrequency ablation (RFA) for persistent AF. A systematic search of the PubMed, EMBASE, and Cochrane Library databases was performed for studies comparing the outcomes between CBA and RFA. Seven trials including 934 patients were analyzed. There were no differences between groups in terms of freedom from atrial arrhythmia (risk ratio [RR], 1.04; 95% CI, 0.93-1.15; P = 0.52; I2= 0%), procedural complications (RR, 0.91; 95% CI, 0.52-1.59; P = 0.74; I2= 0%), atrial fibrillation or atrial tachycardia relapse during the blanking period (RR, 0.73; 95% CI, 0.50-1.06; P = 0.1; I2= 9%), repeat ablation (RR, 0.74; 95% CI, 0.45-1.21; P = 0.23; I2= 62%), and vascular complications (RR, 0.98; 95% CI, 0.42-2.27; P = 0.97; I2= 0%). Cryoballoon ablation increased the incidence of conversion to sinus rhythm during ablation (RR, 1.69; 95% CI, 1.01-2.83; P = 0.046; I2= 0%) and phrenic nerve palsy (PNP; RR, 3.05; 95% CI, 0.95-9.8; P = 0.06; I2= 0%), while RFA increased the risk of cardiac tamponade (RR, 0.27; 95% CI, 0.06-1.25; P = 0.09; I2= 0%). Subanalyses revealed a lower incidence of recurrent atrial arrhythmia and repeat ablation during CBA without touch‑up RFA in pulmonary vein isolation. CBA provides an alternative technique for persistent AF ablation. It might reduce the risk of repeat ablation and cardiac tamponade but increase the risk of PNP.

Ablation for persistent atrial fibrillation (AF) remains a difficult and time-consuming procedure with varying degrees of success. We evaluated the long-term effects of a novel approach for ablation of persistent AF using multi-electrode catheters. In 89 patients with longstanding persistent AF (>1 year), multi-electrode ablation was performed with a pulmonary vein ablation catheter (PVAC), a multi-array septal catheter (MASC), and a multi-array ablation catheter (MAAC) for ablation of complex-fractionated atrial electrograms (CFAE) at the septum, left atrial (LA) roof, floor, posterior wall, and mitral isthmus. Follow-up was performed at 6 and 12 months with electrocardiogram, 7 days Holter, and occasionally ambulant event recordings. Average procedure and fluoroscopy times were 112 ± 32 and 21 ± 10 min. The pre-specified endpoint of pulmonary vein isolation and LA CFAE ablation was reached in all patients. No procedural complications were observed. At 12 months after a single treatment 44 of 89 (49%) remained in sinus rhythm, including direct current cardioversion in 12 patients. At 12 months, after a redo PVAC/MASC/MAAC, an additional 6 of 15 patients (40%) were free of AF. In 18 of 89 (20%) patients AF was changed to paroxysmal. In this single centre study, ablation for longstanding persistent AF with the PVAC/MASC/MAAC resulted in 56% freedom of AF at 1 year after 1.2 ± 0.4 procedures. This approach is time efficient and has a favourable safety profile.

Normal 0 false false false MicrosoftInternetExplorer4 Catheter ablation of atrial fibrillation (AF) has been widely accepted as an important therapeutic modality for the treatment of patients with symptomatic, drug-refractory AF. Ablation strategies which target the pulmonary veins (PVs) and/or the PV antrum (segmental or large circumferential lesions) are the cornerstone of AF ablation procedures, irrespective of the AF type. Successful electrical PV isolation results in maintenance of sinus rhythm in 60 to 85% of patients in patients with paroxysmal AF. However, PV isolation is usually insufficient to eliminate persistent or long-lasting persistent AF leading to significantly lower success rate of this method. Up to now, no single strategy is uniformly effective in patients with persistent and long-lasting persistent AF. Many centers follow a stepwise ablation approach including (i) PV isolation as the initial step; (ii) electrogram-based ablation at all sites in the left atrium and the coronary sinus exhibiting complex fractionated atrial electrograms; (iii) If AF sustains, linear ablation (mainly roof and mitral isthmus lines) is then carried out; and (iv) the right atrium and superior vena cava are finally mapped and ablated. However, such an extensive ablation strategy lead to longer procedure time, longer fluoroscopy time, higher complication rates and higher rates of post-procedural atrial tachycardias. Therefore, the risk/benefit ratio of an extensive ablation approach has to be carefully evaluated. Catheter ablation of persistent and long-lasting persistent AF still remains challenging for the electrophysiologists. The long-term efficacy of certain ablation strategies need to be evaluated in randomized trials.

Predictors of late recurrence after second catheter ablation for persistent atrial fibrillation

Introduction: Predicting heart rate (HR) after restoration of sinus rhythm (SR) remains one of the challenges when performing catheter ablation (CA) of persistent atrial fibrillation (AF). Objectives: To evaluate the association between pre-ablation HR during AF and post-ablation HR during SR, and whether the HR reduction is associated with AF recurrence. Methods: The analysis was performed from the EARNEST-PVI trial, a randomized controlled trial designed to assess a CA strategy for persistent AF, which was conducted in the Osaka region of Japan. After excluding patients with beta-blocker prescription, a total of 216 patients (median age, 67 years; 20% female; 23% long-standing persistent AF) with AF rhythm at baseline and SR at discharge were enrolled in this study. Baseline HR during AF and post-ablation HR during SR was measured on admission and at discharge using the 12-lead electrocardiograms, respectively. Results: There was a mild correlation between baseline HR (median 82 [interquartile range 72-95] bpm) and post-ablation HR (78 [48-117] bpm) (r = 0.27, p <0.001). Reduction in HR was positively associated with baseline HR (r = 0.79, p <0.001) and was negatively associated with post-ablation HR (r = - 0.37, p <0.001). During the follow-up of 1 year, 56 patients (25.9%) experienced AF recurrence. HR reduction had the higher diagnostic accuracy in predicting AF recurrence than HR at baseline and HR after CA (area under the curve, 0.625; 95% confidence interval, 0.557-0.690; p = 0.003). AF recurrence rate was significantly higher in 141 patients with smaller HR reduction (cut-off, <14bpm) than those with larger HR reduction (31.9% vs. 14.7%, p = 0.009). After adjustment of age, gender, long-standing persistent AF, and CA strategy, HR reduction of <14 bpm was a significant predictor of AF recurrence (hazard ratio, 2.32; 95% confidence interval, 1.20-4.51; p = 0.013). Conclusions: There was a mild correlation between HR during AF and HR after restoration of SR in patients underwent CA of persistent AF. HR reduction after restoration of SR predicted AF recurrence.

Little has been reported on the predictors and outcomes of improvement of tricuspid regurgitation (TR) after radiofrequency catheter ablation (RFCA) for persistent atrial fibrillation (AF). We enrolled 141 patients with persistent AF and moderate or severe TR assessed by transthoracic echocardiography (TTE) who underwent an initial RFCA between February 2015 and August 2021. These patients underwent follow-up TTE at 12 months after the RFCA, and were categorized into two groups based on the improvement (defined as at least one-grade improvement of TR) and non-improvement of TR: IM group and Non-IM group, respectively. We compared the patient characteristics, ablation procedures, and recurrences after the RFCA between the two groups. In addition, we examined the major event (defined as admission for heart failure or all-cause death) more than 12 months after the RFCA. IM group consisted of 90 patients (64%). A multivariate analysis revealed that age <71 years old and absence of late recurrence (LR, defined as recurrence of atrial tachyarrhythmia between 3 and 12 months after the RFCA) were independently associated with the improvement of TR after the RFCA. Furthermore, IM group had the higher incidence of major event-free survival than Non-IM group. Relatively young age and absence of LR were good predictors of improvement of TR after the RFCA for persistent AF. In addition, the improvement of TR was related to better clinical outcomes.

Funding Acknowledgements Abbott Medical Japan, Medtronic Japan, Boston Scientific Japan, Biotronic Japan, Japan Life Line Background / Introduction Although sick sinus syndrome(SSS) can be associated with atrial fibrillation(AF), predictive factors of SSS following catheter ablation(CA) of persistent atrial fibrillation(perAF) are not well known. Purpose We investigated echocardiographic parameters to predict occurrence of SSS after restoration of sinus rhythm by CA for perAF patients. Methods Ninety-eight consecutive perAF patients from June 2014 to May 2018 treated with CA were retrospectively reviewed. Twelve patients(12%, SSS group) developed SSS after successful CA and 86 patients(88%, non-SSS group) did not. Baseline characteristics, blood exam, and echocardiographic findings(RA area size, LA area size, EF, etc) before AF CA were analyzed using Student’s t test, Mann-Whitney test, Chi-square test and Univariate analysis. Multivariate logistic analysis was then performed using those parameters. The atrial area size was calculated from 4 chamber view at the atrial end- systole. Results The multivariate analysis for predictive factors of SSS is shown in the table. Right atrium(RA) area could predict SSS(17.3 ± 4.8cm2 vs. 14.7 ± 3.6cm2, odds ratio 1.468; 95% confidence interval 1.088 to 1.981, p = 0.012). Gender (female) was also an independent predictor(4/12 (33%) vs. 8/86 (9%), odds ratio 39.832; 95% confidence interval 2.589 to 612.938, p = 0.008). The other echocardiographical findings(LA area size, EF, etc), baseline characteristics and blood exam results were not related to SSS after successful CA of perAF patients. Conclusions The large RA area size and gender (female) could predict SSS in perAF patients after restoration of sinus rhythm by successful CA. We may need to inform possible SSS after CA to female patients with a large RA before CA. Multivariate Logistic analysis Total(N = 98) SSS group (N = 12) Non SSS group (N = 86) Odds ratio 95% CI P-value Age 64(58-69) 68(60-72) 63(57-69) 1.032 0.929-1.145 0.560 Gender/Female 12(12%) 4(33%) 8(9%) 39.832 2.589-612.938 0.008 CKD 27(28%) 6(50%) 21(24%) 1.264 0.179-8.945 0.814 BNP 91(53-180) 206(167-304) 82(48-169) 1.003 0.993-1.012 0.609 RDW 45.1 ± 3.9 46.4 ± 4.8 44.9 ± 3.8 1.242 0.971-1.588 0.085 RA area 15.1 ± 3.8 17.3 ± 4.8 14.7 ± 3.6 1.468 1.088-1.981 0.012 LA area 24.2(17.0-24.9) 24.4(17.7-26.3) 24.1(16.8-24.4) 0.967 0.803-1.165 0.726 Right atrium area and gender were the independent predictor of SSS in persistent atrial fibrillation patients after restoration of sinus rhythm

A new era of atrial fibrillation (AF) treatment began in 1997–1998 with the discovery that triggers within the pulmonary veins initiate AF and reports that elimination of these triggers is successful in treating AF in its paroxysmal form.1–3 However, in patients with persistent AF, the success rate of exclusive pulmonary vein isolation is substantially lower.4,5 To improve the outcome of persistent AF ablation, different ablation strategies have been explored, but to date the optimal strategy has not been defined. Although some groups argue that limited ablation, including pulmonary vein isolation and, if present, ablation of nonpulmonary vein triggers, is sufficient for persistent AF ablation, other groups, including ours, favor more extensive, substrate-based ablation in addition to pulmonary vein isolation. In this review, we will discuss the rationale for a substrate-based ablation strategy to treat persistent AF and show why elimination of triggers is not sufficient in most patients with persistent AF. Response by Roten et al on p 1232 In a simple model, an electric impulse in AF can form because of abnormalities in impulse generation (triggers) or can result from abnormal impulse propagation (reentry). By a strict definition, a trigger is a focal source of new impulse generation. The mechanism by which a new impulse can form is either abnormal automaticity or triggered activity. Trigger-ablation protocols target these sources of new impulse generation. Abnormal impulse propagation, on the other hand, depends on altered substrate properties causing nonuniform or slowed conduction. This in turn causes multiple forms of wave reentry thought to be responsible for AF perpetuation: random reentry (multiple wavelets), macro- and microreentry, or functional reentry (rotors). Substrate-based ablation strategies aim to abate abnormal impulse propagation and interrupt any form of atrial reentry. Triggers of paroxysmal AF are mainly located in the pulmonary …

Catheter ablation has become the first line of therapy in patients with symptomatic, recurrent, drug-refractory atrial fibrillation. However, catheter ablation of persistent atrial fibrillation is still a challenge. Various rather complex ablation strategies exist and their results are not very favorable. Therefore, the aim of our study was to evaluate a well-defined reasonable approach to catheter ablation of persistent atrial fibrillation. The strategy consisted of a circumferential pulmonary vein ablation in combination with a potential-guided segmental approach to achieve complete pulmonary vein isolation and a linear lesion at the roof of the left atrium. A total of 43 patients (30 men, 13 women; mean age 55 years (SD ± 9 years)) with symptomatic persistent atrial fibrillation were enrolled in this study. All patients underwent catheter ablation of persistent atrial fibrillation using the above-mentioned approach (with the CARTO or the NAVX system). Additionally, catheter ablation of the mitral isthmus and the right atrial isthmus was performed in selected cases. In all patients, cardiac MRI or multi-detector spiral computed tomography was performed prior to the ablation procedure and a surface rendered model of the left atrium was created. After discharge, patients were scheduled for repeated visits at the arrhythmia clinic at 1, 3, 6, 9, and 12 months after the ablation procedure. The ablation procedure could be performed as planned in all 43 patients. Nine patients had to undergo a repeat ablation procedure, so that a total of 52 procedures were evaluated. An additional linear lesion was created at the mitral isthmus in three patients (7%) during the initial procedure and in one patient (2.3%) during the second procedure. Catheter ablation of the right atrial isthmus was performed in 11 patients (25.6%) during the first procedure and in four additional patients during the redo procedure (9.3%). Twenty-four out of 43 patients (55.8%) experienced an arrhythmia recurrence within the first 3 months after ablation requiring an electrical cardioversion. At 1-year follow-up, analysis of a 7-day Holter monitoring revealed no evidence for an arrhythmia recurrence in 26 of 43 patients (60.5%). In nine of 43 patients (20.9%), only short episodes of paroxysmal atrial fibrillation were documented. In eight patients (18.6%), a recurrence of persistent atrial fibrillation (>48 h) was revealed by the long-term recordings. A duration of persistent atrial fibrillation >3 months was the most powerful predictor for arrhythmia recurrences at 1-year follow-up. A subgroup analysis revealed a markedly higher rate of stable sinus rhythm at 1-year follow-up in patients with a short duration of atrial fibrillation (≤ 3 months) compared to patients with a longer duration of AF (>3 months) prior to the procedure (72.0% versus 44.4%). There were no major complications. Catheter ablation of persistent atrial fibrillation can be performed safely and effectively using this ablation strategy (especially in patients with short-lasting persistent atrial fibrillation (≤ 3 months)).

BackgroundOver the last 20 years various techniques have been developed striving for safer and more durable pulmonary vein isolation (PVI). The popularity and uptake of ‘single-shot’ strategies, which by their...

The relationship between coronary blood flow during atrial fibrillation (AF) and improvement of cardiac function after catheter ablation (CA) for persistent AF (PeAF) is not prominent; this study was conducted to evaluate this relationship. This was a retrospective case-control study. Eighty-five patients with PeAF (resting heart rate < 100bpm) and heart failure with reduced ejection fraction (left ventricular ejection fraction (LVEF) < 40%) who had undergone coronary angiography within 1week before CA were included. All patients could maintain a sinus rhythm for > 6months after CA. The primary outcome was improvement of cardiac function with an LVEF cutoff value of > 50% during sinus rhythm 6months after CA. In the LVEF improvement group (N = 57), patients were younger, with a higher baseline diastolic blood pressure and lower baseline brain natriuretic peptide level than the no LVEF improvement group (N = 28). Heart rate at baseline and 6months after CA and AF duration did not differ between the two groups. Thrombolysis in myocardial infarction frame count parameters was significantly higher in the LVEF improvement (P < 0.001) than in the no LVEF improvement group. Multivariate logistic regression analysis revealed mean thrombolysis in myocardial infarction frame count as an independent factor for LVEF improvement (odds ratio, 1.72 (95% confidence interval 1.17-2.54); P = 0.006). Coronary blood flow in patients with PeAF is strongly associated with improved left ventricular systolic function after the restoration of sinus rhythm by CA for PeAF and heart failure with reduced ejection fraction.

Funding Acknowledgements Type of funding sources: Private company. Main funding source(s): Johnson &amp; Johnson KK OnBehalf OCVC Arrhythmia Investigators Background Predicting heart rate (HR) after restoration of sinus rhythm (SR) remains one of the challenges when performing catheter ablation (CA) of persistent atrial fibrillation (AF). Purpose To evaluate the association between pre-ablation HR during AF and post-ablation HR during SR, and whether the HR reduction is associated with AF recurrence. Methods The analysis was performed from the EARNEST-PVI trial, a randomized controlled trial designed to assess a CA strategy for persistent AF, which was conducted in the Osaka region of Japan. After excluding patients with beta-blocker prescription, a total of 216 patients (median age, 67 years; 20% female; 23% long-standing persistent AF) with AF rhythm at baseline and SR at discharge were enrolled in this study. Baseline HR during AF and post-ablation HR during SR was measured on admission and at discharge using the 12-lead electrocardiograms, respectively. Results There was a mild correlation between baseline HR (median 82 [interquartile range 72-95] bpm) and post-ablation HR (78 [48-117] bpm) (r = 0.27, p &amp;lt;0.001). Reduction in HR was positively associated with baseline HR (r = 0.79, p &amp;lt;0.001) and was negatively associated with post-ablation HR (r = - 0.37, p &amp;lt;0.001). During the follow-up of 1 year, 56 patients (25.9%) experienced AF recurrence. HR reduction had the higher diagnostic accuracy in predicting AF recurrence than HR at baseline and HR after CA (area under the curve, 0.625; 95% confidence interval, 0.557–0.690; p = 0.003). AF recurrence rate was significantly higher in 141 patients with smaller HR reduction (cut-off, &amp;lt;14bpm) than those with larger HR reduction (31.9% vs. 14.7%, p = 0.009). After adjustment of age, gender, long-standing persistent AF, and CA strategy, HR reduction of &amp;lt;14 bpm was a significant predictor of AF recurrence (hazard ratio, 2.32; 95% confidence interval, 1.20–4.51; p = 0.013). Conclusions There was a mild correlation between HR during AF and HR after restoration of SR in patients underwent CA of persistent AF. HR reduction after restoration of SR predicted AF recurrence.