2012 HRS/EHRA/ECAS Expert Consensus Statement on Catheter and Surgical Ablation of Atrial Fibrillation: recommendations for patient selection, procedural techniques, patient management and follow-up, definitions, endpoints, and research trial design

Omitting transesophageal echocardiography before catheter ablation of atrial fibrillation

BACKGROUND

Data about necessity of performing transesophageal echocardiography (TOE) prior to every catheter ablation (CA) of atrial fibrillation (AF) is scarce. We aimed to evaluate the safety of an individualized risk-based approach to TOE with respect to thromboembolic cerebrovascular events (CVE) in patients undergoing CA for AF or left atrial tachycardia (AT).

METHODS

We performed a retrospective clinical study based on our institutional registry database. Patients undergoing CA for AF or left-sided AT following initial AF ablation at two participating centers were enrolled. Prior to the procedure, patients were scheduled for TOE only if they had a history of thromboembolic stroke, left atrial appendage (LAA) thrombus, or inappropriate anticoagulation regimen in the previous 3 to 4 weeks. The incidence of periprocedural cerebrovascular thromboembolic events was assessed.

RESULTS

We analyzed 1155 patients (median age 70 years, 54.8% male, 48.1% had persistent AF/AT). In 261 patients, a TOE was performed; in 2 patients (0.7%), an LAA thrombus was detected, which led to cancellation of the catheter ablation; in 894 patients, the TOE was omitted. Of the 1153 (0.35%) patients who underwent ablation, 4 (0.35%) experienced a CVE (one TIA and three strokes). The rate of CVE in our study does not exceed that reported in most multicenter trials. The low event rates limited statistical analysis of possible risk factors for CVE. In all 4 patients with CVE, post-CVE imaging showed the absence of LAA thrombus.

CONCLUSIONS

An individualized selective approach to TOE before catheter ablation of AF or left AT showed a very low risk of overt intraprocedural thromboembolic events for the population in our study. A further randomized controlled study is needed to determine whether TOE prior to catheter ablation without ICE could be omitted in patients with uninterrupted OAC without previous thromboembolic events or a history of left atrial thrombus.

Cryoballoon pulmonary vein isolation versus radiofrequency ablation of the pulmonary veins and left atrial posterior wall: Patient-reported outcomes

BACKGROUND

Data are lacking on patient-reported outcomes (PRO) following cryoballoon ablation (CBA) versus radiofrequency ablation (RFA). We sought to evaluate QoL and clinical outcomes of cryoballoon pulmonary vein isolation only (CRYO-PVI-ONLY) versus RFA with PVI and posterior wall isolation (RF-PVI+PWI) in a large prospective PRO registry.

METHODS

Patients who underwent AF ablation (2013-2016) at our institution were enrolled in an automated, prospectively maintained PRO registry. CRYO-PVI-ONLY patients were matched (1:1) with RF-PVI+PWI patients based on age, gender, and type of AF (paroxysmal vs. persistent). QoL and clinical outcomes were assessed using PRO surveys at baseline and at 1-year. The atrial fibrillation symptom severity scale (AFSSS) was the measure for QoL. Additionally, we assessed patient-reported clinical improvement, arrhythmia recurrence, and AF burden (as indicated by AF frequency and duration scores).

RESULTS

A total of 296 patients were included (148 in each group, 72% paroxysmal). By PRO, a significant improvement in QoL was observed in the overall study population and was comparable between CRYO-PVI-ONLY and RF-PVI+PWI (baseline median AFSSS of 11.5 and 11; reduced to 2 and 4 at 1 year, respectively; p = 0.44). Similarly, the proportion of patients who reported improvement in their overall QoL and AF related symptoms was high and similar between the study groups [92% (CRYO-PVI-ONLY) vs. 92.8% (RF-PVI+PWI); p = 0.88]. Arrhythmia recurrence was significantly more common in the CRYO-PVI-ONLY group (39.7%) compared to RF-PVI+PWI (27.7 %); p = 0.03. Comparable results were observed in paroxysmal and persistent AF.

CONCLUSION

CRYO-PVI-ONLY and RF-PVI+PWI resulted in comparable improvements in patient reported outcomes including QoL and AF burden; with RF-PVI+PWI being more effective at reducing recurrences.

Chinese guidelines for the diagnosis and management of atrial fibrillation

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia, significantly impacting patients' quality of life and increasing the risk of death, stroke, heart failure, and dementia. Over the past two decades, there have been significant breakthroughs in AF risk prediction and screening, stroke prevention, rhythm control, catheter ablation, and integrated management. During this period, the scale, quality, and experience of AF management in China have greatly improved, providing a solid foundation for the development of the guidelines for the diagnosis and management of AF. To further promote standardized AF management, and apply new technologies and concepts to clinical practice timely and fully, the Chinese Society of Cardiology of Chinese Medical Association and the Heart Rhythm Committee of Chinese Society of Biomedical Engineering jointly developed the Chinese Guidelines for the Diagnosis and Management of Atrial Fibrillation. The guidelines comprehensively elaborated on various aspects of AF management and proposed the CHA2DS2‑VASc‑60 stroke risk score based on the characteristics of the Asian AF population. The guidelines also reevaluated the clinical application of AF screening, emphasized the significance of early rhythm control, and highlighted the central role of catheter ablation in rhythm control.

Dynamic Pulmonary Vein Stenosis After Left Pneumonectomy

Pulmonary vein stenosis might be caused by mediastinal migration into the vacated pleural space after pneumonectomy. In a patient complaining of worsening dyspnea in the left lateral decubitus position after left pneumonectomy, transthoracic echocardiography during different postures revealed pulmonary vein stenosis that worsened in the left lateral position.

Pulmonary Vein Isolation With or Without Left Atrial Appendage Ligation in Atrial Fibrillation: The aMAZE Randomized Clinical Trial

Importance

Left atrial appendage elimination may improve catheter ablation outcomes for atrial fibrillation.

Objective

To assess the safety and effectiveness of percutaneous left atrial appendage ligation adjunctive to catheter pulmonary vein isolation for nonparoxysmal atrial fibrillation.

Design, Setting, and Participants

This multicenter, prospective, open-label, randomized clinical trial evaluated the safety and effectiveness of percutaneous left atrial appendage ligation adjunctive to planned pulmonary vein isolation for nonparoxysmal atrial fibrillation present for less than 3 years. Eligible patients were randomized in a 2:1 ratio to undergo left atrial appendage ligation and pulmonary vein isolation or pulmonary vein isolation alone. Use of a 2:1 randomization ratio was intended to provide more device experience and safety data. Patients were enrolled from October 2015 to December 2019 at 53 US sites, with the final follow-up visit on April 21, 2021.

Interventions

Left atrial appendage ligation plus pulmonary vein isolation compared with pulmonary vein isolation alone.

Main Outcomes and Measures

A bayesian adaptive analysis was used for primary end points. Primary effectiveness was freedom from documented atrial arrythmias of greater than 30 seconds duration 12 months after undergoing pulmonary vein isolation. Rhythm was assessed by Holter monitoring at 6 and 12 months after pulmonary vein isolation, symptomatic event monitoring, or any electrocardiographic tracing obtained through 12 months after pulmonary vein isolation. Primary safety was a composite of predefined serious adverse events compared with a prespecified 10% performance goal 30 days after the procedure. Left atrial appendage closure was evaluated through 12 months after pulmonary vein isolation.

Results

Overall, 404 patients were randomized to undergo left atrial appendage ligation plus pulmonary vein isolation and 206 were randomized to undergo pulmonary vein isolation alone. Primary effectiveness was 64.3% with left atrial appendage ligation and pulmonary vein isolation and 59.9% with pulmonary vein isolation only (difference, 4.3% [bayesian 95% credible interval, -4.2% to 13.2%]; posterior superiority probability, 0.835), which did not meet the statistical criterion to establish superiority (0.977). Primary safety was met, with a 30-day serious adverse event rate of 3.4% (bayesian 95% credible interval, 2.0% to 5.0%; posterior probability, 1.0) which was less than the prespecified threshold of 10%. At 12 months after pulmonary vein isolation, complete left atrial appendage closure (0 mm residual communication) was observed in 84% of patients and less than or equal to 5 mm residual communication was observed in 99% of patients.

Conclusions and Relevance

Percutaneous left atrial appendage ligation adjunctive to pulmonary vein isolation did not meet prespecified efficacy criteria for freedom from atrial arrhythmias at 12 months compared with pulmonary vein isolation alone for patients with nonparoxysmal atrial fibrillation, but met prespecified safety criteria and demonstrated high rates of closure at 12 months.

Trial Registration

ClinicalTrials.gov Identifier: NCT02513797.

Evaluation of left atrial strain imaging and integrated backscatter as predictors of recurrence in patients with paroxysmal, persistent, and long-standing persistent atrial fibrillation undergoing catheter ablation

BACKGROUND

Impaired left atrial (LA) strain predicts atrial fibrillation (AF) recurrence after catheter ablation (CA), but currently there is no cut-off to guide patient selection for CA. Integrated backscatter (IBS) is a promising tool for noninvasive quantification of myocardial fibrosis. The aim of this study was to compare LA strain and IBS between paroxysmal, persistent, and long-standing persistent AF and evaluate their association with AF recurrence after CA.

METHODS

Analysis of consecutive patients with symptomatic paroxysmal and persistent AF who underwent CA. LA phasic strain, strain rate and IBS were assessed by two-dimensional speckle-tracking at baseline.

RESULTS

We analyzed 78 patients, 31% with persistent AF (46% long-standing AF), 65% male, mean age 59 ± 14 years, who underwent CA and were followed-up for 12 months. AF recurrence occurred in 22 (28%) patients. LA phasic strain parameters were significantly impaired in patients with AF recurrence and were independent predictors of AF recurrence in a multivariable analysis. LA reservoir strain (LASr) < 18% predicted AF recurrence with 86% sensitivity and 71% specificity, with a higher predictive power compared to LA volume index (LAVI). LASr < 22% in paroxysmal AF and LASr < 12% in persistent AF correlated with AF recurrence. Increased IBS was a predictor of AF recurrence in patients with paroxysmal AF.

CONCLUSION

LA phasic strain parameters were predictors of AF recurrence after CA, independently of LAVI and AF subtype. LASr < 18% showed a higher predictive power compared to LAVI. Further studies are needed to investigate the role of IBS as a predictor of AF recurrence.

Chinese Guidelines for the Diagnosis and Management of Atrial Fibrillation

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia, significantly impacting patients' quality of life and increasing the risk of death, stroke, heart failure, and dementia. Over the past two decades, there have been significant breakthroughs in AF risk prediction and screening, stroke prevention, rhythm control, catheter ablation, and integrated management. During this period, the scale, quality, and experience of AF management in China have greatly improved, providing a solid foundation for the development of guidelines for the diagnosis and management of AF. To further promote standardized AF management, and apply new technologies and concepts to clinical practice in a timely and comprehensive manner, the Chinese Society of Cardiology of the Chinese Medical Association and the Heart Rhythm Committee of the Chinese Society of Biomedical Engineering have jointly developed the Chinese Guidelines for the Diagnosis and Management of Atrial Fibrillation. The guidelines have comprehensively elaborated on various aspects of AF management and proposed the CHA2DS2-VASc-60 stroke risk score based on the characteristics of AF in the Asian population. The guidelines have also reevaluated the clinical application of AF screening, emphasized the significance of early rhythm control, and highlighted the central role of catheter ablation in rhythm control.

Left Atrium Volume Measured with Multislice Computed Tomography as a Prognostic Predictor for Atrial Fibrillation Catheter Ablation Outcomes

Background: Current guidelines consider atrial fibrillation (AF) type as the prognostic factor for a recommendation of catheter ablation. We aimed to determine whether LA and LA appendage (LAA) volumes measured using multislice computed tomography (MSCT) were related to long-term outcomes in AF following radiofrequency catheter ablation (RFCA). Methods: We evaluated 152 consecutive patients with drug-refractory AF (median age, 55.8 ± 9.6 years), including 110 male patients, who underwent RFCA in a single center. All patients underwent MSCT imaging for anatomical assessment. The endpoint of this study was documented AF recurrence after RFCA. Results: The overall procedure success rate was 77.6% (n = 118) during a mean follow-up period of 12.6 months. The LA volume was significantly larger for those who experienced AF recurrence after RFCA than for the patients without recurrent AF after the procedure (153.8 ± 29.9 mL vs. 139.2 ± 34.1 mL, p = 0.025). However, LAA volumes were nearly equivalent between the patients with and without AF recurrence after RFCA (16.2 ± 6.3 mL and 14.7 ± 6.5 mL, respectively; p = 0.235). LA volume ≥ 153.2 mL was the optimal cutoff value for estimating AF recurrence after RFCA, with 94% sensitivity and 66% specificity. LA volume remained an independent predictor of both AF recurrence and permanent AF. Conclusions: LA volume as assessed by MSCT might be helpful for identifying patients likely to achieve successful AF ablation. LA volume ≥ 153.2 mL, but not LAA volume, showed good accuracy in predicting AF recurrence after RFCA.

Catheter ablation for non-paroxysmal atrial fibrillation. A review

Atrial fibrillation (AF), the most common cardiac arrhythmia is associated with increased morbidity and mortality. The higher mortality is due to the risk of heart failure and cardioembolic events. This in-depth review focuses on the strategies and efficacy of catheter ablation for non-paroxysmal atrial fibrillation. The main medical databases were searched for contemporary studies on catheter ablation for non-paroxysmal AF. Catheter ablation is currently proven to be the most effective treatment for AF and consists of pulmonary vein isolation as the cornerstone plus additional ablations. In terms of SR maintenance, it is less effective in non-paroxysmal AF than in paroxysmal patients. but the clinical benefit in non-paroxysmal patients is substantially higher. Since pulmonary vein isolation is ineffective, a variety of techniques have been developed, e.g. linear ablations, ablation of complex atrial fractionated electrograms, etc. Another paradox consists in the technique of catheter ablation. Despite promising results in early observation studies, further randomized studies have not confirmed the initial enthusiasm. Recently, a new approach, pulsed-field ablation, appears promising. This is an in-depth summary of current technologies and techniques for the ablation of non-paroxysmal AF. We discuss the benefits, risks and implications in the treatment of patients with non-paroxysmal AF.

Rethinking appropriate blanking period after atrial fibrillation ablation

BACKGROUND

Early recurrence (ER) within a 90-day blanking period (BP) in catheter ablation (CA) for atrial fibrillation (AF) is a risk factor for late recurrence (LR) after 90 days postoperatively. However, few reports have examined them in the second CA and compared them to the first CA. Moreover, in recent years, there have been reports suggesting that BP should be reduced from 90 to 30 days. Therefore, the association between ER and LR in the first and the second CA was examined, and the validity of a 30-day BP was evaluated.

METHODS

A total of 511 consecutive patients undergoing the first CA and 116 of these patients undergoing the second CA for AF at a single institution from November 2016 to December 2020 were analyzed retrospectively.

RESULTS

When ER within a 90-day BP was divided into 0-30 days and 31-90 days according to the timing of the last ER episode, the hazard ratios on LR of them relative to no ER were 2.7 {95% confidence interval (CI) 1.7-4.2} and 9.7 (95% CI 6.6-14.3), respectively, for the first CA and 15.3 (95% CI 4.7-50.1) and 44.1 (95% CI 14.0-139.4), respectively, for the second CA.

CONCLUSIONS

ER was strongly associated with LR, especially in patients with the last episode of ER more than 30 days after CA. This was pronounced in cases after the second CA, when PVI appeared to be completed. With the current improvement in PVI durability, BP may be acceptable for 30 days.

Ablation Versus Antiarrhythmic Drugs as First-Line Therapy for Treatment-Naive Atrial Fibrillation: A Systematic Review and Meta-Analysis

Evidence on the relative safety and efficacy of atrial fibrillation catheter ablation and antiarrhythmic drugs (AADs) as the first-line therapy for patients with treatment-naive atrial fibrillation (AF) remains disputed. Digital databases were queried to identify relevant randomized controlled trials. The incidence of recurrent AF, major adverse cardiovascular events, and its components (all-cause death, nonfatal stroke, and bleeding) were compared using the DerSimonian and Laird method under the random-effects model to calculate pooled unadjusted risk ratio (RR) with 95% confidence intervals (CIs). A total of 6 randomized controlled trials consisting of 1,120 patients (574 ablation and 549 AADs) were included in the final analysis. Over a median follow-up of 1 year, the risk of any AF recurrence (RR 0.54, 95% CI 0.39 to 0.75) was significantly lower in patients receiving ablation than in patients receiving AADs. However, there was similar risk of major adverse cardiovascular events (RR 2.65, 95% CI 0.61 to 11.46), trial-defined composite end point of adverse events (RR 0.71, 95% CI 0.28 to 1.80), stroke (RR 2.42, 95% CI 0.22 to 26.51), all-cause mortality (RR 1.98, 95% CI 0.28 to 13.90), and procedure/medication failure (RR 2.65, 95% CI 0.61 to 11.46) with both therapies. In conclusion, in patients presenting with treatment-naive AF, ablation as a first-line therapy lowers the risk of AF recurrence with no associated increase in major adverse events, stroke, and mortality compared with AADs.

Clinical Characteristics and Rhythm Outcomes in Patients With Atrial Myopathy After Successful Catheter Ablation of Atrial Fibrillation

BACKGROUND

Although successful atrial fibrillation (AF) ablation can maintain sinus rhythm and reduce the left atrial (LA) dimension, blunted LA reverse remodeling can be observed in patients with atrial myopathy. We explored the potential mechanisms and long-term outcomes in patients with blunted LA reverse remodeling after successful AF catheter ablation.

METHODS AND RESULTS

We included 1685 patients who underwent baseline and 1-year follow-up echocardiograms, had a baseline LA dimension ≥40 mm, and did not have a recurrence of AF within a year. The patients were divided into tertile groups according to the delta value of the change in LA dimension on the preprocedure and 1-year postprocedure echocardiography. After propensity score matching for age, sex, AF type, and LA dimension, 1272 patients were finally included in the analyses (424 in each group; the least/blunted, moderate, and the most reverse remodeling group). The patients in the T1 group (blunted LA reverse remodeling) were independently associated with higher left ventricular mass index (odds ratio [OR], 1.014 [95% CI, 1.005-1.022], P=0.001), change in ΔH2FPEF score (heavy, hypertensive, atrial fibrillation, pulmonary hypertension, elder, filling pressure) score (OR, 1.445 [95% CI, 1.121-1.861], P=0.004), ventricular epicardial adipose tissue volume (OR, 1.010 [95% CI, 1.003-1.017], P=0.003), thinner LA wall thickness (OR, 0.461 [95% CI, 0.271-0.785], P=0.004), lower LA voltage (OR, 0.670 [95% CI, 0.499-0.899], P=0.008), and showed higher long-term AF recurrence (log-rank P<0.001) than other groups.

CONCLUSIONS

Blunted LA reverse remodeling after AF catheter ablation, which is suggestive of atrial myopathy, was independently associated with a larger ventricular epicardial adipose tissue volume and worsening of H2FPEF score. Blunted LA reverse remodeling after AF catheter ablation was also an independent predictor for higher recurrences of AF post-1-year AF catheter ablation.

Association between left atrial low-voltage area and induction and recurrence of macroreentrant atrial tachycardia in pulmonary vein isolation for atrial fibrillation

BACKGROUND

The relationship between induction and recurrence due to atrial tachycardia (AT) and left atrial (LA) matrix progression after atrial fibrillation (AF) ablation remains unclear.

METHODS

One hundred fifty-two consecutive patients with paroxysmal and persistent AF who underwent pulmonary vein isolation (PVI) and cavo-tricuspid isthmus (CTI) ablation and achieved sinus rhythm before the procedure were classified into three groups according to the AT pattern induced after the procedure: group N (non-induced), F (focal pattern), and M (macroreentrant pattern) in 3D mapping.

RESULTS

The total rate of AT induction was 19.7% (30/152) in groups F (n = 13) and M (n = 17). Patients in group M were older than those in groups N and F, with higher CHADS2/CHA2DS2-VASc values, left atrial enlargement, and low-voltage area (LVA) size of LA. The receiver operating characteristic curve determined that the cut-off LVA for macroreentrant AT induction was 8.8 cm2 (area under the curve [AUC]: 0.86, 95% confidence interval [CI]: 0.75-0.97). The recurrence of AT at 36 months in group N was 4.1% (5/122), and at the second ablation, all patients had macroreentrant AT. Patients with AT recurrence in group N had a wide LVA at the first ablation, and the cut-off LVA for AT recurrence was 6.5 cm2 (AUC 0.94, 95%CI 0.88-0.99). Adjusted multivariate analysis showed that only LVA size was associated with the recurrence of macroreentrant AT (odds ratio 1.21, 95%CI 1.04-1.51).

CONCLUSIONS

It is important to develop a therapeutic strategy based on the LVA size to suppress the recurrence of AT in these patients.

Deep learning in vivo catheter tip locations for photoacoustic-guided cardiac interventions

Significance

Interventional cardiac procedures often require ionizing radiation to guide cardiac catheters to the heart. To reduce the associated risks of ionizing radiation, photoacoustic imaging can potentially be combined with robotic visual servoing, with initial demonstrations requiring segmentation of catheter tips. However, typical segmentation algorithms applied to conventional image formation methods are susceptible to problematic reflection artifacts, which compromise the required detectability and localization of the catheter tip.

Aim

We describe a convolutional neural network and the associated customizations required to successfully detect and localize in vivo photoacoustic signals from a catheter tip received by a phased array transducer, which is a common transducer for transthoracic cardiac imaging applications.

Approach

We trained a network with simulated photoacoustic channel data to identify point sources, which appropriately model photoacoustic signals from the tip of an optical fiber inserted in a cardiac catheter. The network was validated with an independent simulated dataset, then tested on data from the tips of cardiac catheters housing optical fibers and inserted into ex vivo and in vivo swine hearts.

Results

When validated with simulated data, the network achieved an F 1 score of 98.3% and Euclidean errors (mean ± one standard deviation) of 1.02 ± 0.84    mm for target depths of 20 to 100 mm. When tested on ex vivo and in vivo data, the network achieved F 1 scores as large as 100.0%. In addition, for target depths of 40 to 90 mm in the ex vivo and in vivo data, up to 86.7% of axial and 100.0% of lateral position errors were lower than the axial and lateral resolution, respectively, of the phased array transducer.

Conclusions

These results demonstrate the promise of the proposed method to identify photoacoustic sources in future interventional cardiology and cardiac electrophysiology applications.

Characteristics of right pulmonary vein with an epicardial connection needing additional carina ablation for isolation

Background

This study thought to elucidate the anatomical features that can predict an epicardial connection (EC) between the right pulmonary vein (RPV) and right atrium.

Methods

We retrospectively analyzed 251 consecutive patients undergoing initial radiofrequency pulmonary vein isolation. We defined EC as present when RPV could not be isolated with circumferential ablation and additional ablation for the conduction gap if needed, and RPV isolation could be achieved by ablation for the earliest activation site >10 mm inside the initial ablation line. Using computed tomography data, we evaluated the RPV bifurcation angle, and the area occupation ratio of the carina region to the RPV antrum (ARC) for predicting EC. In subjects with EC undergoing RPV activation mapping after circumferential ablation, the correlation between conduction delay and bipolar/unipolar potential voltage in the carina region was investigated.

Results

There were ECs in 45 out of 251 patients (17.9%). The RPV bifurcation angle (47.7° vs. 38.8°, p < .001) and ARC (37.2% vs. 29.7%, p < .001) were significantly greater in the EC (+) group. Multivariate logistic regression analysis revealed that RPV bifurcation angle (odds ratio [OR]: 1.994, p = .002) and ARC (OR: 3.490, p = .013) were independent predictors of EC. In nine patients with EC undergoing carina region mapping, the unipolar potential voltage was correlated with conduction delay in RPV with EC (R = -0.401, p < .001).

Conclusion

Anatomical features suggesting a wider RPV carina region could predict the presence of EC, and potential with high voltage could be helpful for detecting EC connection sites.

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

INTRODUCTION

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

METHODS

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

CONCLUSION

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

TRIAL REGISTRATION

(ClinicalTrials.gov ID: NCT04704986).

Early Remodeling of the Left Atrium Following Catheter Ablation of Atrial Fibrillation: Insights From DECAAFII

BACKGROUND

Left atrial (LA) enlargement is prevalent among atrial fibrillation (AF) patients and constitutes an important marker of atrial myopathy. Several studies have described reduction in LA volume post-catheter ablation (CA) of AF, however, none have investigated differences related to additional ablation outside the pulmonary veins (PVs).

OBJECTIVES

The authors sought to study early LA remodeling following CA of persistent AF and the impact of additional, fibrosis-guided extra-PV ablation.

METHODS

In this DECAAF II (Effect of MRI-Guided Fibrosis Ablation vs Conventional Catheter Ablation on Atrial Arrhythmia Recurrence in Patients With Persistent Atrial Fibrillation) trial subanalysis, patients with persistent AF were randomized to receive pulmonary vein isolation (PVI) only or PVI + fibrosis-guided ablation. Late gadolinium enhancement magnetic resonance imaging (LGE-MRI) was performed before and 3 months after CA. Patients were followed up with single-lead electrocardiogram devices for 12 to18 months. AF burden was calculated as days with AF divided by days monitored.

RESULTS

This analysis included 733 patients. The mean LA volume index (LAVI) before ablation was 62.0 mm3/m2 and after ablation was 51.3 mm3/m2, with a mean reduction of 10.7 mm3/m2 (P < 0.001). Patients in the fibrosis-guided ablation arm had more volume reduction than did those in the PVI-only group (12.1 mm3/m2 vs 9.3 mm3/m2; P = 0.02). LAVI reduction was greater in patients with heart failure (15.7 vs 8.9; P = 0.001) and was associated with improved left ventricular ejection fraction (LVEF) (r = 0.23; P < 0.001), reduced AF burden (r = -0.173; P < 0.001), improved LVEF, and improved quality of life (r = 0.146; P < 0.001).

CONCLUSIONS

We confirmed the presence of LA remodeling within 3 months after ablation for persistent AF. Importantly, we saw more LA volume reductions in patients in the PVI + fibrosis-guided ablation arm in comparison with PVI only, and in patients with LV dysfunction. LA volume reduction in response to CA is associated with decreased arrhythmia recurrence, reduced AF burden, and improved LVEF and quality of life.

An expert review of the inverse problem in electrocardiographic imaging for the non-invasive identification of atrial fibrillation drivers

BACKGROUND AND OBJECTIVE

Electrocardiographic imaging (ECGI) has emerged as a non-invasive approach to identify atrial fibrillation (AF) driver sources. This paper aims to collect and review the current research literature on the ECGI inverse problem, summarize the research progress, and propose potential research directions for the future.

METHODS AND RESULTS

The effectiveness and feasibility of using ECGI to map AF driver sources may be influenced by several factors, such as inaccuracies in the atrial model due to heart movement or deformation, noise interference in high-density body surface potential (BSP), inconvenient and time-consuming BSP acquisition, errors in solving the inverse problem, and incomplete interpretation of the AF driving source information derived from the reconstructed epicardial potential. We review the current research progress on these factors and discuss possible improvement directions. Additionally, we highlight the limitations of ECGI itself, including the lack of a gold standard to validate the accuracy of ECGI technology in locating AF drivers and the challenges associated with guiding AF ablation based on post-processed epicardial potentials due to the intrinsic difference between epicardial and endocardial potentials.

CONCLUSIONS

Before performing ablation, ECGI can provide operators with predictive information about the underlying locations of AF driver by non-invasively and globally mapping the biatrial electrical activity. In the future, endocardial catheter mapping technology may benefit from the use of ECGI to enhance the diagnosis and ablation of AF.

Real-time cardiovascular magnetic resonance-guided radiofrequency ablation: A comprehensive review

Cardiac magnetic resonance (CMR) imaging could enable major advantages when guiding in real-time cardiac electrophysiology procedures offering high-resolution anatomy, arrhythmia substrate, and ablation lesion visualization in the absence of ionizing radiation. Over the last decade, technologies and platforms for performing electrophysiology procedures in a CMR environment have been developed. However, performing procedures outside the conventional fluoroscopic laboratory posed technical, practical and safety concerns. The development of magnetic resonance imaging compatible ablation systems, the recording of high-quality electrograms despite significant electromagnetic interference and reliable methods for catheter visualization and lesion assessment are the main limiting factors. The first human reports, in order to establish a procedural workflow, have rationally focused on the relatively simple typical atrial flutter ablation and have shown that CMR-guided cavotricuspid isthmus ablation represents a valid alternative to conventional ablation. Potential expansion to other more complex arrhythmias, especially ventricular tachycardia and atrial fibrillation, would be of essential impact, taking into consideration the widespread use of substrate-based strategies. Importantly, all limitations need to be solved before application of CMR-guided ablation in a broad clinical setting.

Association of Atrial Fibrillation Recurrence with Right Coronary Atherosclerosis and Increased Left Arterial Epicardial Fat Following Catheter Ablation-Results of a Multimodality Study

BACKGROUND

Identification of predictors for atrial fibrillation (AF) recurrence after pulmonary vein isolation (PVI) can lead to better long-term results. Our aim was to investigate the association between novel CT imaging markers reflecting the severity of coronary atherosclerosis and the risk of recurrence following PVI.

METHODS

This study included 80 patients with paroxysmal/persistent AF who underwent PVI. The patients were divided into two groups: Group 1-23 patients with recurrence and Group 2-57 patients without recurrence.

RESULTS

Patients with recurrence presented with a more enlarged left atrial diameter and reduced left ventricle EF, as assessed by echocardiography. Elevated calcium scores and right coronary artery (RCA) stenosis were correlated with a higher risk of AF recurrence (25.38 ± 4.1% vs. 9.76 ± 2.32%, p = 0.001). Patients with AF recurrence presented a higher left atrial volume index (LAVI) (61.38 ± 11.12 mm3/m2 vs. 46.34 ± 12.27 mm3/m2, p < 0.0001). The bi-atrial volume index (BAVI) was similarly higher in the AF recurrence group (98.23 ± 14.44 mm3/m2 vs. 76.48 ± 17.61 mm3/m2, p < 0.0001). Increased EAT volumes located around the LA (EAT-LA) were correlated with recurrence (25.55 ± 6.37 vs. 15.54 ± 8.44, p < 0.0001).

CONCLUSIONS

RCA stenosis, together with atrial volumes and EAT-AS evaluated by CCTA, is associated with the risk of AF recurrence following PVI.

Incremental predictive utility of a radiomics signature in a nomogram for the recurrence of atrial fibrillation

Background

Recurrence of atrial fibrillation (AF) after catheter ablation (CA) remains a challenge today. Although it is believed that evaluating the structural and functional remodeling of the left atrium (LA) may be helpful in predicting AF recurrence, there is a lack of consensus on prediction accuracy. Ultrasound-based radiomics is currently receiving increasing attention because it might aid in the diagnosis and prognosis prediction of AF recurrence. However, research on LA ultrasound radiomics is limited.

Objective

We aim to investigate the incremental predictive utility of LA radiomics and construct a radiomics nomogram to preoperatively predict AF recurrence following CA.

Methods

A training cohort of 232 AF patients was designed for nomogram construction, while a validation cohort (n = 100) served as the model performance test. AF recurrence during a follow-up period of 3-12 months was defined as the endpoint. The radiomics features related to AF recurrence were extracted and selected to create the radiomics score (rad score). These rad scores, along with other morphological and functional indicators for AF recurrence, were included in the multivariate Cox analysis to establish a nomogram for the prediction of the likelihood of AF recurrence within 1 year following CA.

Results

In the training and validation cohorts, AF recurrence rates accounted for 32.3% (75/232) and 25.0% (25/100), respectively. We extracted seven types of radiomics features associated with AF recurrence from apical four-chamber view echocardiography images and established a rad score for each patient. The radiomics nomogram was built with the rad score, AF type, left atrial appendage emptying flow velocity, and peak atrial longitudinal strain. It outperformed the nomogram building without the rad score in terms of the predictive efficacy of CA outcome and showed favorable performance in both cohorts.

Conclusion

We revealed the incremental utility of a radiomics signature in the prediction of AF recurrence and preliminarily developed and validated a radiomics nomogram for identifying patients who were at high risk of post-CA recurrence, which contributed to an appropriate management strategy for AF.

Clinical and economic outcomes of a systematic same-day discharge programme after pulmonary vein isolation: comparison between cryoballoon vs. radiofrequency ablation

AIMS

Same-day discharge (SDD) is feasible after pulmonary vein isolation (PVI). We aim to compare prospectively cryoballoon (CRYO) vs. radiofrequency (RF) ablation in a systematic SDD programme.

METHODS AND RESULTS

We prospectively analysed the 617 scheduled PVI performed consecutively at our institution (n = 377 CRYO, n = 240 RF) from 1 April 2019 to 31 December 2022 within a systematic programme of SDD. The feasibility of SDD, the 10-day incidence of urgent/unplanned medical care after discharge (UUC-10), and the cost per procedure due to hospital resource use were studied. The 100 procedures performed during the previous year, in which patients were systematically hospitalized, were used as a control group. Same-day discharge was achieved in 585/617 (95%) procedures, with a significant trend towards a higher monthly SDD rate from 2019 to 2022 (P = 0.03). The frequency of SDD was similar in CRYO (356/377; 94%) vs. RF (229/240; 95%). After SDD, the UUC-10 was 66/585 (11.3%), being similar for CRYO (41/356; 11.5%) and RF (25/229; 10.9%); P = 0.8 (log-rank test). Of these, 10 patients were re-hospitalized, with an identical rate in CRYO-treated (6/356; 1.7%) and RF-treated (4/229; 1.7%) patients and owing to similar causes (4 haematomas, 4 pericarditis, and 2 symptomatic sinus node dysfunction). Same-day discharge was associated with an average savings per procedure of 63% (P < 0.001), but no differences were found between the CRYO and RF (P = 0.8).

CONCLUSION

In a systematic SDD programme, feasibility (95%, increasing over time), safety (11% UUC-10, 1.7% re-hospitalizations), and savings (63% per procedure) were similar for CRYO and RF ablation procedures.

Acute and mid-term outcomes of ablation for atrial fibrillation with VISITAG SURPOINT: the Japan MIYABI registry

AIMS

The effectiveness of pulmonary vein isolation (PVI) guided by VISITAG SURPOINT (VS) has been demonstrated in Western populations. However, data for Asian populations are limited. VS settings may differ for Asians, given their smaller body size. This study aimed to describe outcomes of radiofrequency atrial fibrillation (AF) ablation guided by VS in a large Asian population.

METHODS AND RESULTS

The prospective, observational, multicentre MIYABI registry collected real-world data from patients undergoing VS-guided AF ablation using ThermoCool SmartTouch and ThermoCool SmartTouch SF catheters from 50 Japanese centres. All patients had paroxysmal AF or persistent AF for <6 months. Primary adverse events (PAEs) were evaluated for safety. The primary efficacy endpoint was the proportion of patients with PVI at the end of the procedure. Mid-term effectiveness (up to 12 months) was evaluated by freedom from documented atrial arrhythmias. Of the 1011 patients enrolled, 1002 completed AF ablation. The mean number of VS values per procedure was 428.8 on the anterior wall and 400.4 on the posterior wall. Nine patients (0.9%) experienced PAEs. Upon procedure completion, 99.7% of patients had PVI. Twelve-month freedom from atrial arrhythmia recurrence was 88.5%; 5.7% of patients were re-ablated. At repeat ablation, 54% of RSPV, 73% of RIPV, 70% of LSPV, and 86% of LIPV evaluated remained durably isolated.

CONCLUSION

Despite lower anterior wall VS values compared with the CLOSE protocol (≥550), the present study demonstrated comparable efficacy outcomes, indicating that a VS of ≥550 for the anterior wall may not be necessary for Asian patients.

Comparison of phenprocoumon with direct oral anticoagulants in catheter ablation of atrial fibrillation

Aims

In patients undergoing catheter ablation for atrial fibrillation (AF), direct oral anticoagulants (DOACs) are as effective and safe as the vitamin K antagonist (VKA) warfarin. Phenprocoumon has a different pharmacokinetic profile compared with warfarin and is the most used VKA in Germany. The aim of the study was to compare DOAC with phenprocoumon.

Methods and results

In this retrospective single-centre cohort study, 1735 patients who underwent 2219 consecutive catheter ablations for AF between January 2011 and May 2017 were included. All patients were in-hospital for at least 48 h after catheter ablation. The primary outcome was defined as peri-procedural thrombo-embolic events. The secondary outcome was any bleeding according to the International Society on Thrombosis and Haemostasis (ISTH). The mean age of the patients was 63.3 years. Phenprocoumon was prescribed in 929 (42%) of the cases, and in 697 (31%) dabigatran, 399 (18%) rivaroxaban, and 194 (9%) apixaban. During hospitalization, 37 (1.6%) thrombo-embolic events occurred, including 23 transient ischaemic attacks (TIAs). Compared with the use of phenoprocoumon, the use of DOAC was significantly associated with a lower thrombo-embolic risk [16 (1.2%) vs. 21 (2.2%), odds ratio (OR)], 0.5 [95% confidence interval (CI) 0.2-0.9], P = 0.04. No statistically significant association with bleeding risk was observed [phenprocomoun: 122 (13%); DOAC: 163 (12.6%); OR 0.9 (95% CI 0.7-1.2); P = 0.70]. Interruption of oral anticoagulation (OAC) was associated with an increased risk for thrombo-embolic complications [OR 2.2 (1.1-4.3); P = 0.031], and bleeding [OR 2.5 (95% CI 1.8-3.2), P = 0.001].

Conclusion

In patients undergoing catheter ablation for AF, the use of DOAC was associated with a reduced risk of thrombo-embolic events compared with phenprocoumon. Non-interrupted oral anticoagulation (OAC) therapy was associated with a reduced risk of peri-procedural thrombo-embolic and any bleeding complications.

Quantification of Mechanical Characteristics of Conventional Steerable Ablation Catheters for Treatment of Atrial Fibrillation Using a Heart Phantom

PURPOSE

Accurate and reliable catheter navigation is important in formation of adequate lesions during radiofrequency cardiac catheter ablation. To inform future device design efforts and to characterize the limitations of conventional devices, the focus of this study is to assess and quantify the mechanical performance of manual ablation catheters for pulmonary vein isolation procedures within a phantom heart model.

METHODS

We measured three important metrics: accuracy of catheter tip navigation to target anatomical landmarks at the pulmonary veins (PVs), orientation of the catheter relative to the tissue at the targets, and the delivered force values and their stability and variations at those targets. A stereovision system was used for navigational guidance and to measure the catheter's tip position and orientation relative to the targets. To measure force, piezoelectric sensors were used which were integrated at the targets, whereby operators were instructed to stabilize the catheter to achieve a chosen reference force value.

RESULTS

An overall positioning accuracy of 1.57 ± 1.71 mm was achieved for all targets. No statistical significance was observed in position accuracy between the right and left PVs (p = 0.5138). The orientation of the catheter relative to tissue surface was 41° ± 21° with no statistical significance between targets. The overall force stability was 41 ± 6 g with higher difficulty in force stabilization in the right compared to the left PV (40 ± 8 vs. 43 ± 2 g, p < 0.0001).

CONCLUSION

Based on our results, future improvements to manual catheter navigation for ablation should focus on improving device performance in orientation control and improved force stability.

Serum uric acid: creatinine ratio (UCR) is associated with recurrence of atrial fibrillation after catheter ablation

Background and aims

Studies showed that elevated preoperative serum uric acid(SUA) levels are associated with recurrence of atrial fibrillation(AF) after catheter ablation. UA:creatinine ratio(UCR - UA normalised for renal function) has appeared as a new biomarker and is considered to reflect endogenous UA levels preferably because it eliminates the influence of renal function. This study aimed to investigate the correlation between UCR and recurrence of AF after catheter ablation.

Methods and results

A total of 233 consecutive patients with symptomatic, drug-refractory AF underwent catheter ablation. All participants underwent history-taking, physical examination and blood biochemistry analysis at baseline. After a mean follow-up of 23.99 ± 0.76 months, recurrence ratios for each UCR quartile (from lowest quartile to highest) were 10.9%, 23.6%, 23.6%, and 41.8%, respectively (P = 0.005). Multivariate Cox regression analysis revealed that UCR was an independent predictor of AF recurrence (HR 1.217, 95%CI 1.008-1.468; P = 0.041). Subgroup analysis showed that UCR was associated with AF recurrence in paroxysmal AF (HR 1.426, 95% CI 1.092-1.8608; P = 0.009) and in male patients (HR 1.407, 95% CI 1.015-1.950; P = 0.04). A cut-off point of 4.475 for the UCR had sensitivity of 65.5% and specificity of 59.6% in predicting AF recurrence (P = 0.001).

Conclusion

Our results demonstrate that elevated preoperative UCR is associated with recurrence of AF after catheter ablation, and it indicate UCR maybe a predictive factor for the recurrence of AF.

Gastro-Esophageal Reflux Disease and Paroxysmal Atrial Fibrillation Ablation

Patients undergoing ablation for atrial fibrillation may be at increased risk of developing gastroesophageal reflux disease. We prospectively studied the presence of symptomatic gastroesophageal reflux disease in naïve patients who underwent atrial fibrillation ablation.

METHODS

The presence of typical symptoms suggestive of gastroesophageal reflux disease was clinically assessed by the gastroenterologist at baseline and at 3 months after ablation. In addition to that, all patients underwent upper gastrointestinal endoscopy.

RESULTS

Seventy-five patients were included in two groups: 46 patients who underwent atrial fibrillation ablation (study group) and 29 patients without ablation (control group). Patients with atrial fibrillation ablation were younger (57.76 ± 7.66 years versus 67.81 ± 8.52 years; p = 0.001), predominantly male (62.2% versus 33.3%; p = 0.030) and with higher body mass index (28.96 ± 3.12 kg/m² versus 26.81 ± 5.19 kg/m²; p = 0.046). At three months after the ablation, in the study and control groups, there were 88.9% and 57.1% patients in sinus rhythm, respectively, (p = 0.009). Symptomatic gastroesophageal reflux disease was not more frequent in the study group (42.2% versus 61.9%; p = 0.220). There was no difference in terms of sinus rhythm prevalence in patients with versus without symptomatic gastroesophageal reflux disease (89.5% versus 88.5%; p = 0.709).

CONCLUSION

In this small prospective study, typical symptoms suggestive of gastroesophageal reflux disease were not more frequent three months following atrial fibrillation ablation.

Cardiovascular magnetic resonance pulmonary perfusion for functional assessment of pulmonary vein stenosis

BACKGROUND

Cardiovascular magnetic resonance (CMR) imaging allows to combine pulmonary perfusion measurements and pulmonary venous angiography during a single-session examination with both imaging modules representing the basis for accurate diagnosis and therapeutic stratification of pulmonary vein (PV) stenosis. The present study investigated the clinical utility of dynamic pulmonary perfusion imaging integrated into a comprehensive CMR protocol for the evaluation of patients with suspected PV stenosis.

METHODS

162 patients with clinically suspected PV stenosis after catheter ablation of atrial fibrillation underwent a combined single-session CMR examination (cardiac cine imaging, dynamic pulmonary perfusion, and three-dimensional PV angiography). CMR angiography was used for visual grading of PV stenoses; dynamic pulmonary perfusion imaging was evaluated per lung lobe visually and quantitatively.

RESULTS

All PV stenosis ≥90% showed a visible perfusion deficit of the corresponding lung lobe (60/60, 100%) while all PVs with luminal narrowing <50% exhibited normal pulmonary perfusion (680/680, 100%). However, every third 70-89% stenosis showed a normal pulmonary perfusion (10/31, 32%) while every fourth 50-69% PV stenosis was associated with hypoperfusion of the corresponding lung lobe (9/39, 23%). For quantitative pulmonary perfusion measurements, ROC analysis demonstrated high discriminatory power regarding PV stenosis detection with the highest AUC values for time-to-peak enhancement (cut-off value, 8.5 s).

CONCLUSIONS

The combination of CMR angiography and CMR pulmonary perfusion allowed for assessment of the anatomical degree of PV stenosis and its hemodynamic impact on the pulmonary parenchymal level. Thus, the proposed comprehensive CMR protocol provided an efficient diagnostic work-up of patients with suspected PV stenosis.

Anticoagulation after typical atrial flutter ablation

The problem of anticoagulant therapy after successful atrial flutter catheter ablation has still not been resolved despite the socio-economic importance of cardiogenic thromboembolism prevention in atrial flutter. Current anticoagulation strategy in patients with atrial flutter based on guidelines for atrial fibrillation. Inappropriate anticoagulation strategy in patients with atrial flutter is a cause of thromboembolic complications. On the other hand, these patients have a high risk of post procedural bleeding.

Left Atrial Appendage Volume Predicts Atrial Fibrillation Recurrence after Radiofrequency Catheter Ablation: A Meta-Analysis

BACKGROUND

The influence of left atrial appendage volume (LAAV) on the recurrence of atrial fibrillation (AF) following radiofrequency catheter ablation remains unclear.

OBJECTIVES

We performed a meta-analysis to assess whether LAAV is an independent predictor of AF recurrence following radiofrequency catheter ablation.

METHODS

The PubMed and the Cochrane Library databases were searched until March 2022 to identify publications evaluating LAAV in association with AF recurrence after radiofrequency catheter ablation. Seven studies that fulfilled the specified criteria of our analysis were found. We used the Newcastle-Ottawa Scale to evaluate the quality of the studies. The pooled effects were evaluated depending on standardized mean differences (SMDs) or hazard ratios (HRs) with 95% confidence intervals (CIs). P values < 0.05 were considered statistically significant.

RESULTS

A total of 1017 patients from 7 cohort studies with a mean follow-up 16.3 months were included in the meta-analysis. Data from 6 studies (943 subjects) comparing LAAV showed that the baseline LAAV was significantly higher in patients with AF recurrence compared to those without AF (SMD: -0.63; 95% CI: -0.89 to -0,37; all p values < 0.05; I2= 62.6%). Moreover, higher LAAV was independently associated with a significantly higher risk of AF recurrence after radiofrequency catheter ablation (HR: 1.10; 95% CI: 1.02 to 1.18).

CONCLUSIONS

The meta-analysis showed that there is a significant correlation between LAAV and AF recurrence after radiofrequency catheter ablation, and the role of LAAV in AF patients should not be ignored in clinical practice.

Detailed investigation of the lesion formation with a novel contact force sensing catheter with a mesh‐shaped irrigation tip

Background

Recently, a novel contact force (CF) sensing catheter with mesh-shaped irrigation tip (TactiFlex SE, Abbott) was invented and is expected to be useful for safe and effective radiofrequency ablation. However, this catheter's detailed characteristics of the lesion formation are unknown.

Methods

With an in vitro model, TactiFlex SE and its predecessor, FlexAbility SE, were used. A cross-sectional analysis of 60 s lesions (combination of various energy power settings [30, 40, and 50 W], and CFs [10, 30, and 50 g]) and longitudinal analysis (combination of various powers [40 or 50 W], CFs [10, 30, and 50 g] and ablation times [10, 20, 30, 40, 50, and 60 s]) of both catheters were analyzed and compared.

Results

One hundred eighty RF lesions were created in protocol 1 and 300 in protocol 2. The lesion formation, impedance changes, and steam pops characteristics were similar between the two catheters. Higher CFs were related to higher incidences of steam pops. A nonlinear, time-dependent increase in the lesion depth and diameter was observed for all power and CF settings, and linear, positive correlations between the RF delivery time and lesion volume were observed for all power settings. Compared with 40 W, a 50 W ablation created greater lesions. Longer durations with higher CF settings had a higher steam pop incidence.

Conclusions

The lesion formation and incidence of steam pops with TactiFlex SE and FlexAbility SE were similar. A 40 or 50 W ablation with careful CF control not to exceed 30 g in addition to monitoring impedance drops was required to safely create transmural lesions.

Treatment Planning for Atrial Fibrillation Using Patient-Specific Models Showing the Importance of Fibrillatory-Areas

Computational models have made it possible to study the effect of fibrosis and scar on atrial fibrillation (AF) and plan future personalized treatments. Here, we study the effect of area available for fibrillatory waves to sustain AF. Then we use it to plan for AF ablation to improve procedural outcomes. CARPentry was used to create patient-specific models to determine the association between the size of residual contiguous areas available for AF wavefronts to propagate and sustain AF [fibrillatory area (FA)] after ablation with procedural outcomes. The FA was quantified in a novel manner accounting for gaps in ablation lines. We selected 30 persistent AF patients with known ablation outcomes. We divided the atrial surface into five areas based on ablation scar pattern and anatomical landmarks and calculated the FAs. We validated the models based on clinical outcomes and suggested future ablation lines that minimize the FAs and terminate rotor activities in simulations. We also simulated the effects of three common antiarrhythmic drugs. In the patient-specific models, the predicted arrhythmias matched the clinical outcomes in 25 of 30 patients (accuracy 83.33%). The average largest FA (FAmax) in the recurrence group was 8517 ± 1444 vs. 6772 ± 1531 mm2 in the no recurrence group (p < 0.004). The final FAs after adding the suggested ablation lines in the AF recurrence group reduced the average FAmax from 8517 ± 1444 to 6168 ± 1358 mm2 (p < 0.001) and stopped the sustained rotor activity. Simulations also correctly anticipated the effect of antiarrhythmic drugs in 5 out of 6 patients who used drug therapy post unsuccessful ablation (accuracy 83.33%). Sizes of FAs available for AF wavefronts to propagate are important determinants for ablation outcomes. FA size in combination with computational simulations can be used to direct ablation in persistent AF to minimize the critical mass required to sustain recurrent AF.

Efficacy and Safety Ablation Index-Guided High-Energy Linear Ablation for Persistent Atrial Fibrillation: PVI Plus Linear Ablation of Mitral Isthmus and Posterior Box Isolation

BACKGROUND

For patients with persistent atrial fibrillation (AF), whether linear ablation should be performed remains controversial, and the efficacy and safety for ablation index (AI)-guided high-energy linear ablation of mitral isthmus (MI) and left atrial (LA) posterior box isolation is still unclear. The aims of this study were to assess the feasibility and clinical success rate of pulmonary veins isolation (PVI) combined with linear ablation of LA roof and posterior inferior (posterior wall isolation) and MI compare with the PVI-alone method in patients of persistent AF.

METHODS AND RESULTS

362 consecutive persistent AF patients were enrolled from two electrophysiology centers. A total of 200 cases were in PVI-plus group and 162 cases were in PVI-alone group. The PVI-alone group received wide circumferential isolation of both ipsilateral pulmonary veins. PVI combined with linear ablation of left atrial posterior wall isolation (LAPWI)and MI were performed in the PVI-plus group. The primary study end point was the first recurrence of an atrial arrhythmia. After 24 months, freedom from the primary endpoint was achieved in 73.5% of the patients in the PVI-plus group and 62.5% in the PVI-alone group (hazard ratio = 0.62, 95% confidence interval: 0.43-0.91, log rank p = 0.012). The procedure-related complication rates were 2.5% in PVI-plus group and 1.9% in PVI-alone group (p = 0.808).

CONCLUSION

In this study, the ablation strategy of ablation (PVI plus linear ablation of mitral isthmus and posterior box isolation) was feasible and safe for persistent AF patients. Compared with the PVI-alone method, it improved outcomes in patients with persistent AF.

Impact of redo ablation for atrial fibrillation on patient-reported outcomes and quality of life

INTRODUCTION

Catheter ablation for atrial fibrillation (AF) is frequently used for the purpose of rhythm control and improved quality of life (QoL). Although success rates are high, a significant proportion of patients require redo ablation. Data are scarce on patient-centered outcomes and QoL in patients undergoing redo AF ablation. We aimed to assess QoL and clinical outcomes using a large prospectively maintained patient-reported outcomes (PRO) registry.

METHODS

All patients undergoing redo AF ablation (2013-2016) at our center were enrolled in a prospective registry for outcomes and assessed for QoL using automated PRO surveys (baseline, 3 and 6 months after ablation, every 6 months thereafter). Data were collected over 3 years of follow-up. The atrial fibrillation symptom severity scale (AFSSS) was used as the main measure for QoL. Additional variables included patient-reported improvement, AF burden, and AF-related healthcare utilization including emergency room (ER) visits and hospitalizations.

RESULTS

A total of 848 patients were included (28% females, mean age 63.8, 51% persistent AF). By automated PRO, significant improvement in QoL was noted (baseline median AFSSS of 12 [5-18] and ranged between 2 and 4 on subsequent assessments; p < .0001), with ≥70%of patients reported remarkable improvement in their AF-related symptoms. The proportion of patients in AF at the time of baseline survey was 36%, and this decreased to <8% across all time points during follow-up (p < .0001). AF burden was significantly reduced (including frequency and duration of episodes; p < .0001), with an associated decrease in healthcare utilization after 6 months from the time of ablation (including ER visits and hospitalizations; p < .0001). The proportion of patients on anticoagulants or antiarrhythmics decreased on follow-up across all time points (p < .0001 for all variables).

CONCLUSION

Most patients derive significant QoL benefit from redo AF ablation; with reduction of both AF burden and healthcare utilization.

Machine learning-based analysis of risk factors for atrial fibrillation recurrence after Cox-Maze IV procedure in patients with atrial fibrillation and chronic valvular disease: A retrospective cohort study with a control group

Objectives

To evaluate the efficacy of the Cox-Maze IV procedure (CMP-IV) in combination with valve surgery in patients with both atrial fibrillation (AF) and valvular disease and use machine learning algorithms to identify potential risk factors of AF recurrence.

Methods

A total of 1,026 patients with AF and valvular disease from two hospitals were included in the study. 555 patients received the CMP-IV procedure in addition to valve surgery and left atrial appendage ligation (CMP-IV group), while 471 patients only received valve surgery and left atrial appendage ligation (Non-CMP-IV group). Kaplan-Meier analysis was used to calculate the sinus rhythm maintenance rate. 58 variables were selected as variables for each group and 10 machine learning models were developed respectively. The performance of the models was evaluated using five-fold cross-validation and metrics including F1 score, accuracy, precision, and recall. The four best-performing models for each group were selected for further analysis, including feature importance evaluation and SHAP analysis.

Results

The 5-year sinus rhythm maintenance rate in the CMP-IV group was 82.13% (95% CI: 78.51%, 85.93%), while in the Non-CMP-IV group, it was 13.40% (95% CI: 10.44%, 17.20%). The eXtreme Gradient Boosting (XGBoost), LightGBM, Category Boosting (CatBoost) and Random Fores (RF) models performed the best in the CMP-IV group, with area under the curve (AUC) values of 0.768 (95% CI: 0.742, 0.786), 0.766 (95% CI: 0.744, 0.792), 0.762 (95% CI: 0.723, 0.801), and 0.732 (95% CI: 0.701, 0.763), respectively. In the Non-CMP-IV group, the LightGBM, XGBoost, CatBoost and RF models performed the best, with AUC values of 0.738 (95% CI: 0.699, 0.777), 0.732 (95% CI: 0.694, 0.770), 0.724 (95% CI: 0.668, 0.789), and 0.716 (95% CI: 0.656, 0.774), respectively. Analysis of feature importance and SHAP revealed that duration of AF, preoperative left ventricular ejection fraction, postoperative heart rhythm, preoperative neutrophil-lymphocyte ratio, preoperative left atrial diameter and heart rate were significant factors in AF recurrence.

Conclusion

CMP-IV is effective in treating AF and multiple machine learning models were successfully developed, and several risk factors were identified for AF recurrence, which may aid clinical decision-making and optimize the individual surgical management of AF.

Prognostic significance of cardiorenal dysfunction within 1 year after atrial fibrillation ablation in patients with systolic dysfunction

Atrial fibrillation (AF) ablation can improve left ventricular ejection fraction (LVEF) and renal function and can even reduce mortality in patients with impaired LVEF. However, the effect of post-ablation cardiorenal dysfunction on the prognosis of patients with impaired LVEF who underwent AF ablation remains unclear. Of the 1243 consecutive patients undergoing AF ablation, the prognosis of 163 non-dialysis patients who underwent AF ablation with < 50% LVEF was evaluated. The primary outcome was a composite of all-cause mortality, heart failure hospitalization, and a need for modification of the treatment for heart failure. During the median follow-up of 4.2 years after the first AF ablation procedure, the primary outcome occurred in 30 of 163 patients (18%). The receiver operating characteristic curve analysis demonstrated that the post-LVEF (LVEF within 1 year after the procedure, and before the occurrence of primary outcome) had larger areas under the curve (0.70) than the pre-LVEF (LVEF before the procedure), and the most optimal cutoff value was LVEF ≤ 42%. Multivariate analysis demonstrated that patients with post-LVEF ≤ 42% and worsening renal function (WRF; an absolute increase in serum creatinine [SCr] ≥ 0.3 mg/dL compared with the SCr at baseline within 1 year after the procedure and before the occurrence of primary outcome) had a 3.4- to 4.3-fold and 3.4- to 3.7-fold higher risk of the primary outcome compared with those without these predictors, respectively. Patients were categorized using post-LVEF ≤ 42% and WRF as follows: group 1 (post-LVEF > 42% without WRF), group 2 (post-LVEF ≤ 42% without WRF), group 3 (post-LVEF > 42% with WRF), and group 4 (post-LVEF ≤ 42% with WRF). Group 4 had a 15.8-fold (P = 0.0001) higher risk of the primary outcome compared with group 1 after adjusting for pre-procedural factors. In patients with impaired LVEF undergoing AF ablation, post-LVEF ≤ 42% and WRF were independent predictors of poor prognosis. The combination of post-LVEF ≤ 42% and WRF is strongly associated with a poor prognosis in patients with AF undergoing ablation, who with these post-ablation cardiorenal dysfunction may have to be treated more intensively after AF ablation.

Superiority of complete bi-atrial ablation procedure for atrial fibrillation in rheumatic mitral valve disease

INTRODUCTION

The necessity of complete bi-atrial lesion created by radiofrequency clamp and pen for nonparoxysmal atrial fibrillation (AF) in patients with rheumatic mitral valve disease (RMVD) remains unclear.

METHODS

From January 2014 to December 2018, patients with RMVD concomitant with nonparoxysmal AF who underwent mitral valve surgery concomitant surgical ablation were retrospectively enrolled. We divided patients into Group A (complete bi-atrial lesion set created by radiofrequency clamp and pen) and Group B (simplified lesion sets created by radiofrequency clamp alone including bi-atrial ablation with incomplete mitral isthmus line and stand-alone left atrial ablation) according to the surgical ablation lesion sets. Propensity score matching was applied to analyze freedom from atrial tachyarrhythmias between the two groups.

RESULTS

Two hundred eight (38.5%) and 332 (61.5%) patients were divided into Group A and Group B, respectively. In Group B, the proportion of patients with recurrent atrial flutter in the subgroup of bi-atrial ablation with incomplete mitral isthmus line was higher than that in Group A (p = .044). After propensity score matching, there were 203 patients in each group. Better freedom from atrial tachyarrhythmias without antiarrhythmic drugs was obtained in Group A (83.1%, 79.6%, and 65.4%) than Group B (73.1%, 68.4%, and 52.7%) at 12, 36, and 60 months after operation (p = .012).

CONCLUSION

The application of radiofrequency clamp and pen to create complete bi-atrial lesion set in surgical ablation for nonparoxysmal AF in RMVD was associated with superior long-term efficacy.

Posterior wall substrate modification using optimized and contiguous lesions in patients with atrial fibrillation

BACKGROUND

Radiofrequency (RF) linear ablation at the left atrial (LA) roof and bottom to isolate the LA posterior wall using contiguous and optimized RF lesions was evaluated. Achieving isolation of the LA posterior wall is challenging as two continuous linear lesion sets are necessary.

METHODS

Forty consecutive patients with symptomatic atrial fibrillation (AF) and arrhythmia substrates affecting the LA posterior wall underwent posterior wall isolation by linear lesions across the roof and bottom. The cohort was divided into two groups: group 1 (20 patients) linear ablation guided by contact force (CF) only; group 2 (20 patients) guided by ablation index (AI) and interlesion distance.

RESULTS

Bidirectional block across the LA roof and bottom was achieved in 40/40 patients. Additional endocardial RF applications in 5 patients from group 1 vs. 3 patients from group 2 resulted in posterior wall isolation in all patients. Procedure duration was almost equal in both groups. CF and AI were significantly higher in group 2 for the roof line, whereas no statistical difference was found for the bottom line. AI-guided LA posterior wall isolation led to a significantly lower maximum temperature increase. The mean AI value as well as the mean value for catheter-to-tissue CF for the roof line were significantly higher when AI-guided ablation was performed. Standard deviation in group 2 showed a remarkably lower dispersion.

CONCLUSIONS

Ablation index guided posterior wall isolation for substrate modification is safe and effective. AI guided application of the posterior box lesion allows improved lesion formation.

Bi-atrial versus left atrial ablation for patients with rheumatic mitral valve disease and non-paroxysmal atrial fibrillation (ABLATION): rationale, design and study protocol for a multicentre randomised controlled trial

INTRODUCTION

Atrial fibrillation (AF) is common in patients with rheumatic mitral valve disease (RMVD) and increase the risk of stroke and death. Bi-atrial or left atrial ablation remains controversial for treatment of AF during mitral valve surgery. The study aims to compare the efficacy and safety of bi-atrial ablation with those of left atrial ablation among patients with RMVD and persistent or long-standing persistent AF.

METHODS AND ANALYSIS

The ABLATION trial (Bi-atrial vs Left Atrial Ablation for Patients with RMVD and Non-paroxysmal AF) is a prospective, multicentre, randomised controlled study. The trial will randomly assign 320 patients with RMVD and persistent or long-standing persistent AF to bi-atrial ablation procedure or left atrial ablation procedure in a 1:1 randomisation. The primary end point is freedom from documented AF, atrial flutter or atrial tachycardia of >30 s at 12 months after surgery off antiarrhythmic drugs. Key secondary end point is the probability of freedom from permanent pacemaker implantation at 12 months after surgery. Secondary outcomes include the probability of freedom from any recurrence of atrial tachyarrhythmias with antiarrhythmic drugs, AF burden, incidence of adverse events and cardiac function documented by echocardiography at 12 months after operation.

ETHICS AND DISSEMINATION

The central ethics committee at Fuwai Hospital approved the ABLATION trial. The results of this study will be disseminated through publications in peer-reviewed journals and conference presentations.

TRIAL REGISTRATION NUMBER

NCT05021601.

Clinical outcomes and structural remodelling after ablation of atrial fibrillation in heart failure with mildly reduced or mid-range ejection fraction

AIMS

The efficacy of catheter ablation (CA) on clinical outcomes and cardiac structural remodelling in atrial fibrillation (AF) patients with HF with mildly reduced or mid-range ejection fraction (HFmrEF) remains unclear. We aimed to compare the efficacy of CA with medical therapy (MT) in AF patients with HFmrEF.

METHODS AND RESULTS

We retrospectively screened a total of 36 879 patients with AF between 2005 and 2020. Patients who were initially diagnosed with echocardiography-proved HFmrEF and had follow-up echocardiography were enrolled. After applying propensity score matching in a 1:1 ratio, 72 patients treated by CA (Group 1) and 72 patients receiving MT (Group 2) were taken into further analysis. The co-morbidities were similar between the two groups, except for hyperlipidaemia. After a mean follow-up duration of 58.9 ± 42.6 months, Group 1 had a lower HF hospitalization and all-cause mortality compared with Group 2 (hazard ratio (HR), 0.089 [95% confidence interval (CI), 0.011-0.747]; P = 0.026 and HR, 0.121 [95% CI, 0.016-0.894]; P = 0.038, respectively). As for cardiac structural remodelling, the Group 1 had a better improvement in left ventricular ejection fraction (LVEF) and a more decreased left atrium (LA) diameter than Group 2 (+25.0% ± 18.0% vs. +6.2% ± 21.6%, P = <0.0001 and -1.6 ± 4.7 mm vs. +1.5 ± 8.2 mm, P = 0.008, respectively).

CONCLUSIONS

In patients with HFmrEF and AF, CA of AF could reduce both HF hospitalization and all-cause mortality as compared with those with MT. A significant improvement in LVEF and decrease in LA diameter were also observed in the CA group. Early rhythm control with CA should be taken into consideration in patients with HFmrEF and AF.

Influence of pulsating intracardiac blood flow on radiofrequency catheter ablation outcomes in an anatomy-based atrium model

BACKGROUND

Highly consistent cardiac ablation outcomes through radiofrequency catheter ablation (RFCA) under pulsatile and constant flow profiles (PP&CP) of intracardiac blood were previously indicated by computer modeling, with simplified geometry and lossless receipt of inflow for ablation catheters. This study aimed to further investigate the effects of intracardiac blood pulsatility in an anatomy-based atrium model.

METHODS

Four pulmonary veins were blood inflows at 10 mm Hg. The mitral valve was the outflow, with PP based on pulsatile velocity curve from clinical measurements, and CP was obtained by averaging the velocity curve under PP over an ablation time of 30 s. A numerical comparison between ablation results under PP and CP, without experimental validation, was performed.

RESULTS

Temperature fluctuations persisted in mid-myocardium, and most clearly in blood and endocardium under PP. At a constant power of 20 W, marked differences in ablation outcome between PP and CP occurred in the middle of unilateral pulmonary veins and the posterior wall of the left atrium (LA) where the blood velocities were significantly decreased under CP. The mid-myocardial, blood and endocardial temperatures, as well as the effective lesion volume at the former position, were decreased by 4.1%, 15%, 13.6%, and 13.8%, respectively under PP. The extents for the latter position were 11%, 22%, 22.5%, and 55.6%, respectively.

CONCLUSION

Intracardiac flow pulsatility causes a greater reduction in blood and endocardial temperatures at ablation sites away from the main bloodstream, effective cooling of which is more likely to rely on blood velocities approaching peak PP values.

A Modified Maze Versus Cut-and-Sew Maze for Long-Standing Persistent Atrial Fibrillation Concomitant with Mitral Valve Surgery: A Propensity Score-Matched Cohort Study

BACKGROUND

The cut-and-sew maze (CSM) procedure has an excellent efficacy for the elimination of long-standing persistent atrial fibrillation (AF) concomitant with mitral valve surgery. Because of the complexity and prolongation of cardiopulmonary bypass, CSM has not been widely used. The aim of this study was to examine a modified maze procedure that preserves the "cut-and-sew" procedure in the left atrium and uses cryoablation in the right atrium along with cavotricuspid isthmus.

METHODS

From December 2013 to December 2018, 229 patients underwent CSM, and 43 underwent the modified maze procedure during mitral valve surgery. Propensity score matching analysis was used to perform selective 1:2 ratio matching of the 43 patients undergoing the modified maze procedure with 86 patients undergoing CSM. Early operative outcomes were analyzed for differences. The absence of AF recurrence without the use of anti-arrhythmic drugs was calculated at 2 years by a generalized linear model analysis.

RESULTS

One (1.1%) early death occurred in the CSM group, and no deaths occurred in the modified maze group (p=0.722). The aortic cross-clamp durations were 76.30±8.86 minutes for the modified maze and 92.38±10.88 for the CSM procedure (p<0.001). There were no late strokes or deaths during the 2-year follow-up. The modified maze group showed similar rates of absence of AF without the use of anti-arrhythmic drugs as the CSM group within the 2 years (p=0.332).

CONCLUSION

This modified maze simplifies the "cut-and-sew" procedure and reduces operating time while retaining the efficacy of CSM.

Treatment Options in AF Patients with Cancer; Focus on Catheter Ablation

Longer life expectancy along with advancements in cancer and atrial fibrillation (AF) therapies and treatment strategies have led to an increase in the number of individuals with both diseases. As a result, the complicated management of these patients has become crucial, necessitating individualised treatment that considers the bi-directional relationship between these two diseases. On the one hand, giving appropriate pharmaceutical therapy is exceptionally difficult, considering the recognised thromboembolic risk posed by AF and malignancy, as well as the haemorrhagic risk posed by cancer. The alternative pulmonary vein isolation (PVI) ablation, on the other hand, has been inadequately explored in the cancer patient population; there is yet inadequate data to allow the clinician to unambiguously select patients that can undertake this therapeutic intervention. The goal of this review is to compile the most valuable data and supporting evidence about the characteristics, care, and therapy of cancer patients with AF. Specifically, we will evaluate the pharmaceutical options for a proper anticoagulant therapy, as well as the feasibility and safety of PVI in this population.

Cost-utility analysis of Cryoballoon ablation versus Radiofrequency ablation in the treatment of paroxysmal atrial fibrillation in Iran

Atrial fibrillation (AF) is the most prevalent cardiac arrhythmia (Calkins H, et al. 2012). There are various methods to treat AF of which Ablation is one of the most effective. We aimed to assess the cost-utility of Cryoballoon ablation (CBA) compared to Radiofrequency ablation (RFA) to treat patients with paroxysmal AF in Iran. A cost-utility analysis was done using a decision-analytic model based on a lifetime Markov structure which was drawn considering the nature of interventions and the natural progress of the disease. Costs data were extracted from medical records of 47 patients of Shahid Rajaie Cardiovascular Medical Center in Tehran in 2019. Parameters and variables such as transition probabilities, risks related to side effects, mortality rates, and utility values were extracted from the available evidence. Deterministic and probabilistic sensitivity analysis was also done. TreeAge pro-2020 software was used in all stages of analysis. In the base case analysis, the CBA strategy was associated with higher cost and effectiveness than RFA, and the incremental cost-effectiveness ratio was $11,223 per Quality-adjusted life year (QALY), which compared to Iran’s GDP per capita as Willingness to pay threshold, CBA was not cost-effective. On the other hand, considering twice the GDP per capita as a threshold, CBA was cost-effective. Probabilistic sensitivity analysis confirmed the findings of base case analysis, showed that RFA was cost-effective and the probability of cost-effectiveness was 59%. One-way sensitivity analysis showed that the results of the study have the highest sensitivity to changes in the RFA cost variable. Results of sensitivity analysis showed that the cost-effectiveness results were not robust and are sensitive to changes in variables changes. Primary results showed that CBA compared to RFA is not cost-effective in the treatment of AF considering one GDP per capita. But the sensitivity analysis results showed considerable sensitivity to changes of the ablation costs variable.

Influence of atrial fibrillation type on outcomes of ablation vs. drug therapy: results from CABANA

AIMS

Influence of atrial fibrillation (AF) type on outcomes seen with catheter ablation vs. drug therapy is incompletely understood. This study assesses the impact of AF type on treatment outcomes in the Catheter Ablation vs. Antiarrhythmic Drug Therapy for Atrial Fibrillation Trial (CABANA).

METHODS AND RESULTS

CABANA randomized 2204 patients ≥65 years old or <65 with at least one risk factor for stroke to catheter ablation or drug therapy. Of these, 946 (42.9%) had paroxysmal AF (PAF), 1042 (47.3%) had persistent AF (PersAF), and 215 (9.8%) had long-standing persistent AF (LSPAF) at baseline. The primary endpoint was a composite of death, disabling stroke, serious bleeding, or cardiac arrest. Symptoms were measured with the Mayo AF-Specific Symptom Inventory (MAFSI), and quality of life was measured with the Atrial Fibrillation Effect on Quality of Life (AFEQT). Comparisons are reported by intention to treat. Compared with drug therapy alone, catheter ablation produced a 19% relative risk reduction in the primary endpoint for PAF {adjusted hazard ratio [aHR]: 0.81 [95% confidence interval (CI): 0.50, 1.30]}, and a 17% relative reduction for PersAF (aHR: 0.83, 95% CI: 0.56, 1.22). For LSPAF, the ablation relative effect was a 7% reduction (aHR: 0.93, 95% CI: 0.36, 2.44). Ablation was more effective than drug therapy at reducing first AF recurrence in all AF types: by 51% for PAF (aHR: 0.49, 95% CI: 0.39, 0.62), by 47% for PersAF (aHR: 0.53, 95% CI: 0.43,0.65), and by 36% for LSPAF (aHR 0.64, 95% CI 0.41,1.00). Ablation was associated with greater improvement in symptoms, with the mean difference between groups in the MAFSI frequency score favouring ablation over 5 years of follow-up in all subgroups: PAF had a clinically significant -1.9-point difference (95% CI: -1.2 to -2.6); PersAF a -0.9 difference (95% CI: -0.2 to -1.6); LSPAF a clinically significant difference of -1.6 points (95% CI: -0.1 to -3.1). Ablation was also associated with greater improvement in quality of life in all subgroups, with the AFEQT overall score in PAF patients showing a clinically significant 5.3-point improvement (95% CI: 3.3 to 7.3) over drug therapy alone over 5 years of follow-up, PersAF a 1.7-point difference (95% CI: 0.0 to 3.7), and LSPAF a 3.1-point difference (95% CI: -1.6 to 7.8).

CONCLUSION

Prognostic treatment effects of catheter ablation compared with drug therapy on the primary and major secondary clinical endpoints did not differ consequentially by AF subtype. With regard to decreases in AF recurrence and improving quality of life, ablation was more effective than drug therapy in all three AF type subgroups.

CLINICALTRIALS.GOV IDENTIFIER

NCT00911508.

Clinical outcomes in patients with persistent atrial fibrillation after technologic advances including contact force-guided and ablation index-guided ablation

Purpose

We aimed to evaluate the influence of technological advances on ablation outcomes in patients with persistent atrial fibrillation (AF) (PeAF). Radiofrequency ablation for patients with AF has advanced, including contact force (CF)-sensing catheters and the ablation index (AI).

Methods

Between 2009 and 2018, we analyzed 173 patients with PeAF who underwent catheter ablation. We categorized them into three groups: AF ablation without CF and AI information (no-CF group, n = 63), with CF without AI (CF-only group, n = 49), and with optimal AI-guided ablation (AI group, n = 61). Early (within 3 months, ER) and late (from 3 months to 1 year, LR) AF recurrence after ablation was assessed. Procedure-related complications were also evaluated.

Results

The baseline characteristics were similar among the 3 groups, excluding the baseline antiarrhythmic drug history. Additional substrate modification after pulmonary vein isolation was significantly low in frequency in the AI group (71.4%, no-CF; 69.4%, CF-only; 41.0%, AI, p = 0.001). The AI group had a shorter mean procedure-related time than the other groups. Both ER and LR of PeAF showed a trend of reduction with technological advances. With a short experience (less than 1 year), the CF-only group showed more ER and LR than that shown by the AI group. However, with a long experience (more than 1 year), ER and LR occurred similarly in the two groups. Procedure-related complications improved with technological advances.

Conclusion

As ablation technology advanced, favorable clinical outcomes with short procedural times were observed. However, prospective, large multicenter studies are needed to verify these results.

Lessons Learned from a Delayed Diagnosis of Atrioesophageal Fistula: A Multidisciplinary Approach

Atrioesophageal fistulas are a rare complication of radiofrequency ablation that requires rapid identification and emergent surgical repair to prevent morbidity and mortality. We report a case of a 32-year-old man with atrial fibrillation presenting with chest pain followed by rapidly progressive sepsis and embolic cerebrovascular accident 23 days after radiofrequency ablation. Subtle initially overlooked findings on multiple computed tomography caused a delay in diagnosis. Atrioesophageal fistulas remain diagnostically challenging. A high index of suspicion coupled with serial computed tomography of the chest with intravenous and oral contrast reviewed by a multimodal team is essential to make a timely diagnosis. This article is protected by copyright. All rights reserved.

Diabetes Mellitus Is an Independent Risk Factor for a Stiff Left Atrial Physiology After Catheter Ablation for Atrial Fibrillation

Background

Scar tissue formation after catheter ablation for atrial fibrillation (AF) may adversely affect the diastolic properties of the left atrium (LA), which can result in a stiff LA physiology in a small proportion of patients. In this study, we aimed to explore the relationship between diabetes mellitus and a stiff LA physiology after AF catheter ablation (AFCA).

Methods

A total of 1,326 patients who underwent de novo AFCA, and baseline and 1-year follow-up echocardiographies were enrolled. After 1:3 propensity score (PS) matching for age, sex, and AF type, we compared 211 patients with DM with 633 patients without DM. A stiff LA physiology was defined as estimated pulmonary arterial pressure increase of >10 mmHg and a right ventricular systolic pressure of >35 mmHg at 1-year follow-up echocardiography. Pulmonary vascular resistance (PVR) was estimated using echocardiographic parameters.

Results

Among the 844 PS-matched patients, a stiff LA physiology was observed in 32 patients (4.1%). The patients with DM showed a higher peak LA pressure (p < 0.001) and greater LA wall stress (p = 0.001) than did those without. A stiff LA physiology was independently associated with DM [Odds ratio (OR) = 2.39, 95% confidence interval (CI) 1.02-5.59, p = 0.045], empirical extra-pulmonary vein LA ablation (OR = 3.14, 95% CI 1.07–9.3, p = 0.038) and the ΔPVR (OR = 1.78, 95% CI 1.37–2.31, p < 0.001). The ΔPVR was independently associated with DM (β = 0.37, 95% CI 0.06-0.67, p = 0.020) and a stiff LA physiology (β = 1.40, 95% CI 0.70–2.10, p < 0.001). During the 38.8 ± 29.3months follow-up, the incidence of the clinical recurrence of AF was significantly higher in the patients with a stiff LA physiology than in those without (log rank p = 0.032).

Conclusion

A stiff LA physiology was independently associated with DM because of the relatively small decrease in the PVR after AFCA in this population. The patients with a stiff LA physiology had worse rhythm outcomes after AFCA than those without.

The Roles of Fractionated Potentials in Non-Macroreentrant Atrial Tachycardias Following Atrial Fibrillation Ablation: Recognition Beyond Three-Dimensional Mapping

Introduction

Non-macroreentrant atrial tachycardia (nAT) following atrial fibrillation (AF) ablation is being increasingly reported. Many issues remain to be elucidated. We aimed to characterize the fractionated potentials (FPs) in nAT and introduce a new method of cross-mapping for clarifying their roles.

Methods and Results

Forty-four nATs in 37 patients were enrolled and classified into focal AT (FAT, 12), microreentrant AT (MAT, 14), and small-loop-reentrant AT (SAT, 18) groups, according to activation pattern. FP was found on all targets except in nine FATs. The ratio of FP duration to AT cycle length (TCL) was different among groups (28 ± 7% in FAT, 53 ± 11% in MAT, and 42 ± 14% in SAT, p < 0.05), and ablation duration were longer in SATs (313 ± 298 vs. 111 ± 125 s, p < 0.05). The ratio of mappable cycle length to TCL was lower in the FAT group (63 ± 22% vs. 90 ± 9% and 89 ± 8%, p < 0.05). When cross-mapping was employed, trans-potential time differences in both longitudinal and transverse direction were longer around the culprit FP for MAT (p < 0.01). After Receiver Operating Characteristic curve analysis, it is best to adopt the sum of time difference ratios in both directions ≥60% as a cut-off value for discrimination of the FPs responsible for MAT with a sensitivity of 92% and specificity of 87%.

Conclusions

FP could be found on target in most nATs following a previous AF ablation. The ratio of FP duration to TCL may help for differentiation. A simple method of cross-mapping could be employed to clarify the roles of FPs.