Catheter Ablation For Treatment Research Articles

Definition and management of arrhythmia-induced cardiomyopathy: findings from the European Heart Rhythm Association survey.

Arrhythmia-induced cardiomyopathy (AiCM) represents a subtype of acute heart failure (HF) in the context of sustained arrhythmia. Clear definitions and management recommendations for AiCM are lacking. The European Heart Rhythm Association Scientific Initiatives Committee (EHRA SIC) conducted a survey to explore the current definitions and management of patients with AiCM among European and non-European electrophysiologists. A 25-item online questionnaire was developed and distributed among EP specialists on the EHRA SIC website and on social media between 4 September and 5 October 2023. Of the 206 respondents, 16% were female and 61% were between 30 and 49 years old. Most of the respondents were EP specialists (81%) working at university hospitals (47%). While most participants (67%) agreed that AiCM should be defined as a left ventricular ejection fraction (LVEF) impairment after new onset of an arrhythmia, only 35% identified a specific LVEF drop to diagnose AiCM with a wide range of values (5-20% LVEF drop). Most respondents considered all available therapies: catheter ablation (93%), electrical cardioversion (83%), antiarrhythmic drugs (76%), and adjuvant HF treatment (76%). A total of 83% of respondents indicated that adjuvant HF treatment should be started at first HF diagnosis prior to antiarrhythmic treatment, and 84% agreed it should be stopped within six months after LVEF normalization. Responses for the optimal time point for the first LVEF reassessment during follow-up varied markedly (1 day-6 months after antiarrhythmic treatment). This EHRA Survey reveals varying practices regarding AiCM among physicians, highlighting a lack of consensus and heterogenous care of these patients.

Efficacy of catheter ablation in ganglionated plexus for malignant vasovagal syncope children.

Malignant vasovagal syncope in children seriously affects their physical and mental health. Our study aimed to explore the efficacy of catheter ablation in ganglionated plexus with malignant vasovagal syncope children. Catheter ablation of ganglionated plexus was safe and effective in children with malignant vasovagal syncope and can be used as a treatment option for these children. A total of 20 children diagnosed with malignant vasovagal syncope were enrolled in Beijing Children's Hospital, affiliated with Capital Medical University. All underwent catheter ablation treatment of ganglionated plexus. Ganglionated plexuses of the left atrium were identified by high-frequency stimulation and/or anatomic landmarks being targeted by radiofrequency catheter ablation. The efficacy of the treatment was evaluated by comparing the remission rate of post-operative syncopal symptoms and the rate of negative head-up tilt results. Safety and adverse events were evaluated. After follow-up for 2.5 (0.6-5) years, the syncope symptom scores were decreased significantly compared with before treatment [3 (2-4) versus 5 (3-8) scores, P < 0.01]. Eighty-five per cent (17/20) children no longer experienced syncope, whilst 80% (16/20) children showed negative head-up tilt test after treatment. No adverse effects such as cardiac arrhythmia occurred in the children.

Catheter ablation versus medical therapy in atrial fibrillation: an umbrella review of meta-analyses of randomized clinical trials

This umbrella review synthesizes data from 17 meta-analyses investigating the comparative outcomes of catheter ablation (CA) and medical treatment (MT) for atrial fibrillation (AF). Outcomes assessed were mortality, risk of hospitalization, AF recurrence, cardiovascular events, pulmonary vein stenosis, major bleeding, and changes in left ventricular ejection fraction (LVEF) and MLHFQ score. The findings indicate that CA significantly reduces overall mortality and cardiovascular hospitalization with high strength of evidence. The risk of AF recurrence was notably lower with CA, with moderate strength of evidence. Two associations reported an increased risk of pulmonary vein stenosis and major bleeding with CA, supported by high strength of evidence. Improved LVEF and a positive change in MLHFQ were also associated with CA. Among patients with AF and heart failure, CA appears superior to MT for reducing mortality, improving LVEF, and reducing cardiovascular rehospitalizations. In nonspecific populations, CA reduced mortality and improved LVEF but had higher complication rates. Our findings suggest that CA might offer significant benefits in managing AF, particularly in patients with heart failure. However, the risk of complications, including pulmonary vein stenosis and major bleeding, is notable. Further research in understudied populations may help refine these conclusions.

IMPACT OF THYROID DYSFUNCTION IN PATIENTS WITH ATRIAL FIBRILLATION

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia in clinical practice, affecting approximately 2% of the general population and increasing the risk of stroke, heart failure and mortality. AF is often associated with several clinical conditions, including thyroid dysfunction, which can alter metabolism, function and cardiac structure. Thyroid dysfunction can be classified as hypothyroidism (low production of thyroid hormones) or hyperthyroidism (excess production of thyroid hormones), both of which can cause or worsen AF. The mechanism by which thyroid dysfunction affects AF is complex and involves electrophysiological, hemodynamic, inflammatory and structural changes in the atria. Appropriate diagnosis and treatment of thyroid dysfunction can improve AF control and reduce thromboembolic and hemorrhagic complications. However, the prevalence, incidence, risk factors, prognosis and management of AF in patients with thyroid dysfunction are still controversial topics in the literature. Objective: to evaluate the impact of thyroid dysfunction in patients with AF, addressing the following aspects: epidemiology, pathophysiology, diagnosis, treatment and clinical outcomes. Methodology: This review was carried out in accordance with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) protocol. The PubMed, Scielo and Web of Science databases were searched, using the following descriptors: "atrial fibrillation", "thyroid dysfunction", "hypothyroidism", "hyperthyroidism" and "thyrotoxicosis". Articles published in the last 10 years, in Portuguese, English or Spanish, that addressed the proposed topic were included. Articles that were not original, did not have sufficient data or were not relevant to the research question were excluded. Results: 18 studies were selected. The diagnosis of AF in patients with thyroid dysfunction requires confirmation of the heart rhythm by electrocardiogram (ECG) and assessment of serum thyroid hormone levels (TSH, free T4 and free T3). Treatment of AF in patients with thyroid dysfunction aims to restore and maintain sinus rhythm, control ventricular rate, prevent thromboembolic events, and correct thyroid dysfunction. Therapeutic options include antiarrhythmic drugs, antithyroid drugs, anticoagulant drugs, electrical cardioversion, catheter ablation, and surgical thyroid treatment. The clinical outcomes of AF in patients with thyroid dysfunction are influenced by the type, severity and duration of thyroid dysfunction, as well as rhythm, frequency and anticoagulation control. AF in patients with thyroid dysfunction is associated with a higher risk of arrhythmia recurrence, heart failure, stroke and mortality. Conclusion: Thyroid dysfunction is a frequent and important clinical condition in patients with AF, as it can cause or worsen arrhythmia, as well as increase the risk of complications. Appropriate diagnosis and treatment of thyroid dysfunction can improve AF control and reduce adverse outcomes. However, there are still gaps in knowledge about the epidemiology, pathophysiology, prognosis and management of AF in patients with thyroid dysfunction, which require further studies of high quality and clinical relevance.

Predicting Adverse Outcomes Following Catheter Ablation Treatment for Atrial Flutter/Fibrillation

To develop prognostic survival models for predicting adverse outcomes after catheter ablation treatment for non-valvular atrial fibrillation (AF) and/or atrial flutter (AFL). We used a linked dataset including hospital administrative data, prescription medicine claims, emergency department presentations, and death registrations of patients in New South Wales, Australia. The cohort included patients who received catheter ablation for AF and/or AFL. Traditional and deep survival models were trained to predict major bleeding events and a composite of heart failure, stroke, cardiac arrest, and death. Out of a total of 3,285 patients in the cohort, 177 (5.3%) experienced the composite outcome-heart failure, stroke, cardiac arrest, death-and 167 (5.1%) experienced major bleeding events after catheter ablation treatment. Models predicting the composite outcome had high-risk discrimination accuracy, with the best model having a concordance index >0.79 at the evaluated time horizons. Models for predicting major bleeding events had poor risk discrimination performance, with all models having a concordance index <0.66. The most impactful features for the models predicting higher risk were comorbidities indicative of poor health, older age, and therapies commonly used in sicker patients to treat heart failure and AF and AFL. Diagnosis and medication history did not contain sufficient information for precise risk prediction of experiencing major bleeding events. Predicting the composite outcome yielded promising results, but future research is needed to validate the usefulness of these models in clinical practice. Machine learning models for predicting the composite outcome have the potential to enable clinicians to identify and manage high-risk patients following catheter ablation for AF and AFL proactively.

Is catheter ablation associated with preservation of cognitive function? An analysis from the SAGE-AF observational cohort study.

To examine the associations between catheter ablation treatment (CA) vs. medical management and cognitive impairment among older adults with atrial fibrillation (AF). Ambulatory patients who had AF, were ≥65-years-old, and were eligible to receive oral anticoagulation could be enrolled into the SAGE (Systematic Assessment of Geriatric Elements)-AF study from internal medicine and cardiology clinics in Massachusetts and Georgia between 2016 and 2018. Cognitive function was assessed using the Montreal Cognitive Assessment (MoCA) tool at baseline, 1-, and 2 years. Cognitive impairment was defined as a MoCA score ≤ 23. Multivariate-adjusted logistic regression of longitudinal repeated measures was used to examine associations between treatment with CA vs. medical management and cognitive impairment. 887 participants were included in this analysis. On average, participants were 75.2 ± 6.7 years old, 48.6% women, and 87.4% white non-Hispanic. 193 (21.8%) participants received a CA before enrollment. Participants who had previously undergone CA were significantly less likely to be cognitively impaired during the 2-year study period (aOR 0.70, 95% CI 0.50-0.97) than those medically managed (i.e., rate and/or rhythm control), even after adjusting with propensity score for CA. At the 2-year follow-up a significantly greater number of individuals in the non-CA group were cognitively impaired (MoCA ≤ 23) compared to the CA-group (311 [44.8%] vs. 58 [30.1%], p = 0.0002). In this 2-year longitudinal prospective cohort study participants who underwent CA for AF before enrollment were less likely to have cognitive impairment than those who had not undergone CA.

Abstract 16517: Association of Low Left Atrial Appendage Velocity With Increased Risk of Atrial Fibrillation Recurrence After Catheter Ablation: A Meta-Analysis

Background: Catheter ablation (CA) is an effective and potentially curative treatment in patients with atrial fibrillation (AF). However, the recurrence of AF following CA treatment in cases of persistent atrial fibrillation (PeAF) remains a significant concern. This study aims to establish a correlation between the peak flow velocity of the left atrial appendage (LAAV) and the AF recurrence post-CA for PeAF. Methods: PubMed/Medline, EMBASE, and SCOPUS databases were systematically reviewed to find studies through June 2023 reporting data on the relationship between the LAAV and the recurrence of AF in individuals who have undergone CA for PeAF. Binary random effects models were used to estimate pooled outcomes. I2 statistics were used to interpret heterogeneity, with I 2 &gt;75% indicating substantial inter-study variation. Leave-one-out meta-analysis was performed to evaluate the effect of each study on the overall estimate. A p&lt;0.05 was considered statistically significant. Results: A total of 9 studies between 2000-2023 were included in our meta-analysis. The pooled univariate analysis revealed no association between LAAV and recurrence of AF in individuals who have undergone CA with a pooled OR of 1.09 (95CI 0.96-1.22) p=0.45, I2=86.59%. The multivariate analysis, after adjusting for overall modifiable risk factors, yielded significant results, with an adjusted odds ratio (aOR) of 1.41 (95CI 1.15-1.74) p&lt;0.01, I2=85.24%. Sensitivity analysis, using the leave-one-out method&amp;nbsp;demonstrated the robustness and stability of the results, indicating that no single study disproportionately influenced the overall&amp;nbsp;findings with aOR 1.41 (95CI 1.15-1.74) p&lt;0.01. Conclusions: This meta-analysis revealed that low LAAV is associated with high-risk of AF recurrence following CA. Identifying a specific subgroup of individuals at high risk of AF recurrence with the help of pre-CA LAA velocity will facilitate the early institution of alternative treatment strategies.

Catheter ablation versus medical therapy for atrial fibrillation with prior stroke history: a prospective propensity score-matched cohort study.

Patients with atrial fibrillation (AF) and prior stroke history have a high risk of cardiovascular events despite anticoagulation therapy. It is unclear whether catheter ablation (CA) has further benefits in these patients. AF patients with a previous history of stroke or systemic embolism (SE) from the prospective Chinese Atrial Fibrillation Registry study between August 2011 and December 2020 were included in the analysis. Patients were matched in a 1:1 ratio to CA or medical treatment (MT) based on propensity score. The primary outcome was a composite of all-cause death or ischemic stroke (IS)/SE. During a total of 4.1 ± 2.3 years of follow-up, the primary outcome occurred in 111 patients in the CA group (3.3 per 100 person-years) and in 229 patients in the MT group (5.7 per 100 person-years). The CA group had a lower risk of the primary outcome compared to the MT group [hazard ratio (HR) = 0.59, 95% CI: 0.47-0.74, P < 0.001]. There was a significant decreasing risk of all-cause mortality (HR = 0.43, 95% CI: 0.31-0.61, P < 0.001), IS/SE (HR = 0.73, 95% CI: 0.54-0.97, P = 0.033), cardiovascular mortality (HR = 0.32, 95% CI: 0.19-0.54, P < 0.001) and AF recurrence (HR = 0.33, 95% CI: 0.30-0.37, P < 0.001) in the CA group compared to that in the MT group. Sensitivity analysis generated consistent results when adjusting for time-dependent usage of anticoagulants. In AF patients with a prior stroke history, CA was associated with a lower combined risk of all-cause death or IS/SE. Further clinical trials are warranted to confirm the benefits of CA in these patients.

GSM-Net: A global sequence modelling network for the segmentation of short axis CINE MRI images.

Atrial Fibrillation (AF) is a disease where the atria fail to properly contract but quiver instead, due to the abnormal electrical activity of the atrial tissue. In AF patients, anatomical and functional parameters of the left atrium (LA) largely differ from that of healthy people due to LA remodelling, which can continue in many cases after the catheter ablation treatment. Therefore, it is important to follow up with AF patients to detect any recurrence. LA segmentation masks obtained from short-axis CINE MRI images are used as the gold standard for the quantification of LA parameters. Thick slices of CINE MRI images hinder the use of 3D networks for segmentation while 2D architectures often fail to model inter-slice dependencies. This study presents GSM-Net which approximates 3D networks with effective modelling of inter-slice similarities with two new modules: global slice sequence encoder (GSSE) and sequence dependent channel attention module (SdCAt). In contrast to previous work modelling only local inter-slice similarities, GSSE also models global spatial dependencies across slices. SdCAt generates a distribution of attention weights over MRI slices per channel, to better trace characteristic changes in the size of the LA or other structures across slices. We found that GSM-Net outperforms previous methods on LA segmentation and helps to identify AF recurrence patients. We believe that GSM-Net can be used as an automatic tool to estimate LA parameters such as ejection fraction to identify AF, and to follow up with patients after treatment to detect any recurrence.

Advanced integration of stereotaxis and real-time MRI for precise and safe medical navigation: a future paradigm for minimally invasive interventions

Minimally invasive techniques have transformed medicine by improving patient outcomes and reducing invasiveness. Existing navigation methods, which use fluoroscopy or pre-operative imaging, lack real-time visualization and precision during complex surgeries. Fluoroscopy may also expose patients and medical staff to ionizing radiation. We propose enhanced stereotaxis and real-time magnetic resonance imaging (MRI) integration to overcome these problems and improve minimally invasive intervention precision and safety. Stereotactic guiding and high-resolution real-time MRI imaging are combined in this research to improve medical navigation. The conceptual framework includes modeling the stereotactic system's magnetic field, real-time tracking of magnetic-sensored medical devices, and dynamic MRI imaging for continuous visibility throughout treatments. Stereotactic and MRI data can be fused for simultaneous vision and navigation, and adaptive path planning algorithms allow real-time targeting and avoidance of key structures. A simulated cardiac electrophysiology catheter ablation treatment shows the combined approach's potential benefits. Real-time adaptive navigation reduces radiation exposure and problems while targeting precisely. This research establishes a new medical navigation paradigm that improves precision, patient safety, and radiation exposure. This integrated method could revolutionize minimally invasive procedures across medical disciplines, despite limitations in patient-specific data integration and real-time algorithm development. This new navigation approach needs further research, validation, and clinical trials to confirm its feasibility and efficacy and improve medical patient care

Machine learning based prediction of 1-year arrhythmia recurrence after ventricular tachycardia ablation in patients with structural heart disease

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Project no. NVKP_16-1–2016-0017 (’National Heart Program’) - National Research, Development and Innovation Fund of Hungary Thematic Excellence Programme (2020-4.1.1.-TKP2020) of the Ministry for Innovation and Technology in Hungary Background Ventricular tachycardia (VT) is a life-threatening condition. Catheter ablation treatment is often successful, however post procedural VT recurrence still remains an issue. Therefore, there is a demand for an accurate risk stratification system to assess the probability of arrhythmia recurrence after the procedure. Objective We aimed to implement a machine learning (ML) pipeline to predict 1-year VT recurrence in patients with structural heart disease (SHD) undergoing VT ablation. Methods For 297 patients who underwent VT ablation, we collected medical history, laboratory, echocardiography, and procedural data. Following manual and ML-based feature selection, we trained several supervised machine learning models to predict 1-month and 1-year recurrence. The area under the receiver operating characteristic curve (AUC) was calculated to quantify the models’ performance. Results 1-year VT recurrence was observed in 107 (36%) cases. The best predictions of VT recurrence were demonstrated by random forest models utilizing 7 input features [1-month AUC: 0.74; 1-year AUC: 0.76]. These models significantly outperformed a previously published risk score, the I-VT score [AUC: 0.63, p=0.024] on our data. The most important predictors of recurrence were the number of VT morphologies during the procedure, electrical storm, left ventricular ejection fraction, left ventricular end systolic diameter, and the severity of mitral regurgitation. Conclusion Our machine learning model can efficiently predict VT recurrence in SHD patients undergoing VT ablation. Thus, it could facilitate the prompt identification of high-risk patients and the personalization of treatment and follow-up strategies, ultimately leading to improved outcomes.

Outcomes of catheter ablation vs.medical treatment for atrial fibrillation and heart failure: a meta-analysis.

The benefit of catheter ablation vs. medical treatment has been reported to be inconsistent in randomized controlled trials (RCTs) for patients with atrial fibrillation (AF) and heart failure (HF) due to different enrollment criteria. This meta-analysis aimed to decipher the differential outcomes stratified by different left ventricular ejection fractions (LVEFs) and AF types. We searched PubMed, Embase, ProQuest, ScienceDirect, Cochrane Library, ClinicalKey, Web of Science, and ClinicalTrials.gov databases for RCTs comparing medical treatment and catheter ablation in patients with AF and HF published before March 31, 2023. Nine studies were included. When patients were stratified by LVEF, improved LVEF and 6-min walk distance, less AF recurrence, and lower all-cause mortality in favor of catheter ablation were observed in patients with LVEF ≤50% but not in patients with LVEF ≤35%, and short HF hospitalization was observed in patients with LVEF ≤50% and LVEF ≤35%. When patients were stratified by AF types, improved LVEF and 6-min walk distance, better HF questionnaire score, and short HF hospitalization in favor of catheter ablation were observed both in patients with nonparoxysmal AF and mixed AF (paroxysmal and persistent) and less AF recurrence and lower all-cause mortality in favor of catheter ablation were observed in only patients with mixed AF. This meta-analysis showed improved LVEF and 6-min walk distance, less AF recurrence, and lower all-cause mortality in favor of catheter ablation vs. medical treatment in AF patients with HF and LVEF of 36%-50%. Compared with medical treatment, catheter ablation improved LVEF and had better HF status in patients with nonparoxysmal AF and mixed AF; however, AF recurrence and all-cause mortality in favor of catheter ablation were observed in only HF patients with mixed AF.

AB-452666-3 CATHETER ABLATION IN ASIAN PATIENTS WITH ATRIAL FIBRILLATION AND HYPERTROPHIC CARDIOMYOPATHY: ELECTROPHYSIOLOGICAL CHARACTERISTICS OF RECURRENCE AND LONG-TERM CLINICAL OUTCOMES

Catheter ablation (CA) is an effective and safe strategy for treating atrial fibrillation (AF) in patients with hypertrophic cardiomyopathy (HCM). We investigated the electrophysiological characteristics of recurrence at a tertiary referral center and compared the long-term clinical outcomes after CA therapy with patients who did not receive CA. Patients with HCM and AF who underwent CA (group 1, n=60) or pharmacological treatment (group 2, n=298) from 2006 to 2021 were enrolled. The patients’ baseline characteristics and electrophysiological features were examined to elucidate the reason for AF recurrence after CA in part I of the study (group 1). The clinical outcomes of group 1 and group 2 patients were compared using a propensity score (PS)-matched method in part II. In part I, the most common cause of recurrence was pulmonary vein (PV) reconnection (86.5%), followed by non-PV triggers (40.5%), cavotricuspid isthmus flutter (29.7%), and atypical flutter (24.3%). Thyroid disease (HR: 14.713, p<0.001), diabetes (HR: 3.074, p=0.034), and non-paroxysmal AF (HR: 4.012, p=0.007) independently predicted recurrence. After the first recurrence, the patients who underwent repeat CA demonstrated better arrhythmia-free status (74.1%) compared to those who underwent drug-escalation therapy (29.4%, p=0.004). In part II, after matching, PS-group 1 patients had significantly better outcomes in all-cause mortality, heart failure hospitalization, and left atrium reverse remodeling than PS-group 2 patients. Patients who underwent CA had better clinical outcomes than those who did not receive CA. The main recurrence predictors were thyroid disease, diabetes, and non-paroxysmal AF.

Temporal changes in incidence, treatment strategies and 1-year re-admission rates in patients with atrial fibrillation/flutter under 65 years of age: A Danish nationwide study

AimTo examine temporal changes in incidence rates of atrial fibrillation/flutter (AF), treatment strategies, and AF readmission rates in patients <65 years. MethodsUsing Danish nationwide registries, we identified patients <65 years with a first-time AF diagnosis from 2000 to 2018. The cohort was categorized according to calendar periods; 2000–2002, 2003–2006, 2007–2010, 2011–2014, and 2015–2018. In this retrospective cohort study the incidence rate (IR) of AF per 100,000 person years (PY), catheter ablation, electrical cardioversion, use of pharmacotherapy, and AF readmission, were investigated in the first year following AF diagnosis. ResultsWe identified 60,917 patients; 8150 (13.4%) in 2000–2002, 11,898 (19.5%) in 2003–2006, 13,560 (22.3%) in 2007–2010, 14,167 (23.3%) in 2011–2014, and 13,142 (21.6%) in 2015–2018. Apart from 2015 to 2018, a stepwise increase in the crude IR of AF was observed across calendar periods; 2000–2002: 78.7 (95% CI 77.0;80.4), 2003–2006: 86.3 (84.7;87.8), 2007–2010: 97.9 (96.3;99.6), 2011–2014: 102.3 (100.7;104.0), 2015–2018: 93.6 (92.0;95.2). Over the studied time-periods, we found a stepwise increase in the cumulative incidence of catheter ablation (1.2% to 7.6%) electrical cardioversion (2.0% to 8.7%) and treatment with oral anticoagulant therapy (OAC) (28.5% to 47.8%) within the first year of diagnosis. No temporal differences in incidence of 1-year AF readmission were identified (AF-readmissions: 2000–2002: 32.7%, 2003–2006: 31.1%, 2007–2010: 32.2%, 2011–2014: 32.1% and 2015–2018: 31.7%). ConclusionThe incidence rate of AF in patients <65 years increased from 2000 to 2018, as did the use of catheter ablation, electrical cardioversion and OAC in the first year following AF diagnosis. 1-year AF readmission incidence remained stable around 32% over the study period.

Arrhythmias : Update on ablations and devices

The field of invasive electrophysiology is technically evolving and especially the catheter ablation treatment of symptomatic atrial fibrillation (AF). The technically innovative method of so-called electroporation (pulsed field ablation, PFA) is characterized by arapid and effective treatment of AF. The current study data confirm ahigh success rate for ablation and a good safety profile in the treatment of paroxysmal and persistent AF. In the field of radiofrequency ablation (RF) of AF the modified form of energy transfer, the very high-power short-duration (vHPSD) protocols, show good results and can reduce the procedural time. There are also technical innovations in other single-shot devices. There is adevice based on the RF technique that could show good clinical results in an initial study and can combine the targeted delivery of RF energy with the advantages of asingle-shot device. For ventricular tachycardia (VT) there are innovations in the diagnostics and clarification in the new European guidelines that were presented in August 2022. These make individual recommendations for different types of cardiomyopathy. There are also technical developments in the field of active rhythm implants. In cardiac pacemaker treatment and specifically for conduction system pacing (CSP) there is evidence for a targeted stimulation of the bundle of His or left bundle branch pacing (LBBP). This form of stimulation is particularly advantageous for patients with heart failure and abroad QRS complex. For leadless pacemakers (leadless pacing) there are now good long-term results and also atwo-chamber approach.

Structural characteristics of patients with superior vena cava foci initiating atrial fibrillation: Analysis with electrocardiogram-triggered computed tomography.

The superior vena cava (SVC) is the most common source of non-pulmonary vein foci in atrial fibrillation (AF); therefore, predicting the existence of non-pulmonary vein foci before the catheter ablation procedure helps construct a proper ablation strategy in preparation for SVC isolation. This study aimed to clarify the structural characteristics of patients with SVC foci initiating AF. We enrolled 331 consecutive patients with AF who underwent cardiac computed tomography imaging before radiofrequency catheter ablation treatment, and they were divided into SVC (+) and (-) groups based on the presence or absence of SVC foci initiating AF. The SVC (+) group (n = 27) exhibited SVC crescent signs-defined as a curve-shaped SVC with two narrow pointed ends-more frequently (37% vs. 9%, p < .001), and larger right atrial volume (95.6 ± 20.8 vs. 80.5 ± 26.1 mL, p = .004) than the SVC (-) group (n = 304). Multivariate logistic regression analysis revealed that the SVC crescent sign (odds ratio, 8.88; 95% confidence interval [CI], 3.21-24.60) and right atrial volume (odds ratio, 1.03; 95% CI, 1.01-1.04) were independent predictors of SVC foci. Patients with SVC foci exhibited more frequent SVC crescent signs and larger right atrial volumes, and these characteristics may help clinicians choose the appropriate ablation technology.

Global research trends in catheter ablation and surgical treatment of atrial fibrillation: A bibliometric analysis and science mapping.

To evaluate the global research results of the catheter ablation and surgical treatment of atrial fibrillation in the past 40 years by bibliometrics, and to explore the hotspots and prospects for future development. Relevant literatures were selected from the Web of Science Core Collection. VOSviewer 1.6.17, SciMAT 1.1.04, and CiteSpace 5.8.R1 were used to analyze the data objectively, deeply and comprehensively. As of July 14, 2021, 11,437 studies for the catheter ablation and surgical treatment of atrial fibrillation have been identified from 1980 to 2021. The Journal of Cardiovascular Electrophysiology and Circulation respectively ranked first in terms of the number of publications and the number of co-citations. A total of 6,631 institutions from 90 countries participated in the study, with USA leading the way with 3,789 documents. Cryoablation, atrial fibrosis, substrate modification, minimally invasive and access surgery will still be the research focus and frontier in the next few years. The publication information for the catheter ablation and surgical treatment of atrial fibrillation were reviewed, including country, institution, author, journal publications, and so on. Developed countries had the advantage in this research areas, and cooperation with low-income countries should be improved. The former research hotspots in the field of catheter ablation and surgical treatment of atrial fibrillation were analyzed, and the future research direction was predicted.

Abstract 10565: Personalized Virtual Heart Approach Representing Fatty Infiltration (inFAT) in Arrhythmogenic Right Ventricular (RV) Cardiomyopathy (ARVC) Predicts Ventricular Arrhythmia (VA) Reentrant Circuits and Ablation Targets: A Pilot Study

Introduction: inFAT is a pathological hallmark in ARVC that is associated with pro-arrhythmic remodeling that contributes to the substrate for VA. Identification of the inFAT distribution on contrast-enhanced computed tomography (CE-CT), which is highly accessible and has reliable image quality, may be useful in pre-procedural planning for catheter ablation treatment of VA. Objective: We aimed to develop and validate a novel non-invasive CT-based computational approach for VA ablation targeting in ARVC. Methods: As a retrospective pilot study, we constructed 3D personalized computational models of ARVC patient hearts with implanted cardioverter defibrillators from CE-CT scans representing the patient-specific inFAT distribution in the RV (Fig A, B). Three patients were included. P1 and P2 had clinical VA and electrophysiological study with ablation. P3 did not present with clinical VA and did not have ablation. We evaluated the inducibility of each model via rapid pacing and compared the results to electroanatomic voltage maps (EAM). In-silico ablation was performed and compared to clinical ablation locations (Fig C). Results: For all 3 patients, heart model predictions corresponded well with clinical observations.In both P1 and P2, reentrant circuits’ locations matched clinical records (Fig C). Both reentrant circuits manifested at the border of inFAT and fat-myocardium admixture, where tissue heterogeneity was prominent. Regions of inFAT co-localized well with low-voltage areas on EAM. Predicted ablation sites successfully terminated VA and coincided with the clinical ablation locations. In P2, the predicted ablation yielded a much smaller lesion than clinical ablation. For P3, the model correctly predicted that VA could not be induced in the heart. Conclusions: Our novel ARVC CT-based computational approach accurately predicts VA ablation targets and could potentially become a highly accessible tool in assisting ARVC ablation.

Abstract 10183: Structural Characteristics of Patients With Superior Vena Cava Foci Initiating Atrial Fibrillation: Analysis With Electrocardiogram-Triggered Computed Tomography

Introduction: The superior vena cava is the most common source of non-pulmonary vein foci in atrial fibrillation. Hypothesis: Predicting the existence of non-pulmonary vein foci prior to the catheter ablation procedure is helpful because recent one-shot ablation technologies are designed to isolate only the pulmonary veins. We aimed to clarify the structural characteristics of patients with superior vena cava foci initiating atrial fibrillation. Methods: We enrolled 331 consecutive patients with atrial fibrillation who underwent computed tomography cardiac imaging before radiofrequency catheter ablation treatment. The patients were divided into superior vena cava (+) and (-) groups according to having superior vena cava foci or not. The characteristics of 27 patients per group, identified with propensity score matching, were compared. Results: The superior vena cava (+) group exhibited superior vena cava crescent signs, defined as a curve-shaped superior vena cava with two narrow pointed ends, more frequently (40.7% vs. 7.4%, p =0.004), and a right atrial volume larger than the superior vena cava (-) group (95.6 ± 20.8 vs. 83.5 ± 18.7 mL, p =0.030). Multivariate logistic regression analysis revealed that the superior vena cava crescent sign (odds ratio, 8.45; 95% confidence interval, 1.52-46.99) and right atrial volume ≥ 80 mL (odds ratio, 4.66; 95% confidence interval, 1.22-17.79) were independent predictors of superior vena cava foci. Conclusions: Patients with superior vena cava foci exhibited more frequent superior vena cava crescent signs and larger right atrial volumes. These characteristics may help clinicians choose the appropriate ablation technology.

Evaluation of left atrial and left ventricular functions in patients with Wolff-Parkinson-White syndrome before and after radiofrequency catheter ablation using three-dimensional speckle tracking echocardiography.

Wolff-Parkinson-White (WPW) syndrome is one of the most common congenital cardiac abnormalities among ventricular pre-excitation syndromes. Radiofrequency catheter ablation (RFCA) treatment of accessory pathways (APs) in WPW patients is an established curative therapy restoring normal atrioventricular conduction. We have not encountered any studies evaluating both the LA and LV functions of these patients before and after RFCA with three dimensional-speckle tracking echocardiography (3D-speckle tracking echocardiography (STE)). The purpose of the current study was to assess the LA and LV functions in patients with WPW syndrome before and after RFCA using 3D-STE. A total of 21 patients with WPW syndrome who had been scheduled for RFCA were prospectively recruited for this study. 3D-STE examinations of the patients were performed 12-24h before ablation and 1 month after ablation. The LV-global longitudinal strain (LV-GLS) and LV-global circumferential strain (LV-GCS) were significantly depressed in the pre-RFCA WPW group than in the control group (-14.3±2.1vs. -21.5±2.2, p<.001; -12.6±1.8vs. -20.4±1.8, p<.001, respectively). The left atrial strain-reservoir (LAS-r) and LAS-active were significantly decreased in the pre-RFCA WPW group than in the control group (31.9±2.4vs. 48.8±2.6, p<.001; 11.7±2vs. 26.5±2.1, p<.001, respectively). The LV-GLS, LV-GCS, LAS-r, and LAS-active values improved after RFCA compared to before. The results of our study indicated that there are subclinical impairments in LV and LA myocardial dynamics in the apparently healthy WPW patients, and these deteriorations improve after RFCA of AP.