Catheter Ablation Research Articles

Impact of Fat on the Left Atrial Roof Identified with Intracardiac Echocardiography during Pulmonary Vein Isolation Procedures

BackgroundPrevious studies have reported the presence of fat between the septopulmonary bundle (SPB) and septoatrial bundle (SAB) on the left atrial (LA) roof. This fat may increase the wall thickness and protect the SPB from radiofrequency energy, potentially leading to conduction gaps. ObjectiveThis study aimed to determine whether fat on the LA roof can be identified using intracardiac echocardiography (ICE) and whether its presence affects the procedural outcomes of pulmonary vein isolation (PVI). MethodsWe evaluated 94 patients undergoing first-time radiofrequency catheter ablation (RFCA) for atrial fibrillation (AF) (60 males [63.8%], mean age 65.7±10.7 years, 46 paroxysmal AF [48.9%]) between February 2021 and September 2023. ICE was used to visualize the LA roof, and hypoechoic regions suggestive of fat were marked within the CARTO®-Sound map. PVI was then performed with a personalized isolation line, avoiding fat regions when feasible. ResultsFat on the LA roof was identified in 35 of 94 patients (37.2%). Conduction gaps on the left PV roof were observed in 7 of 35 patients (20.0%) with fat and 1 of 59 patients (1.7%) without fat (P=0.004). Among patients with conduction gaps, 7 of 8 (87.5%) had a PVI line that crossed a fat region. No significant differences were noted in conduction gaps in other areas between the two groups. ConclusionThe findings indicate that the presence of fat on the LA roof, as identified by ICE, may be associated with a higher incidence of conduction gaps following PVI.

Los indicadores de calidad de la Sociedad Europea de Cardiología en fibrilación auricular en centros de excelencia en España: el registro SEC-EXCELENTE FA

Introduction and objectives By 2022, 9 centers had been accredited by the Spanish Society of Cardiology for the atrial fibrillation (AF) process. Our objective was to evaluate the performance of these centers based on the quality indicators (QIs) proposed by the European Society of Cardiology (ESC) in 2020.Methods Adults with AF who were attended in the cardiology departments of participating centers during the second week of May 2019 were included in a retrospective registry (n = 797, age 72 ± 11 years, 60% male). Key ESC QIs were assessed.Results CHA2DS2-VASc, HAS-BLED scores, and serum creatinine levels were documented in 24.9%, 6.1%, and 96.2% of patients, respectively. Anticoagulation was appropriately prescribed in 90.6% of high-risk patients according to the CHA2DS2-VASc score, but was inappropriately prescribed in 57.8% of low-risk patients. Among all patients, 84.1% received high-quality anticoagulation. Inappropriate antiarrhythmic drugs were prescribed in 7.2% of patients with permanent AF, 2.9% of those with structural heart disease, and 0.0% of those with end-stage kidney disease. Catheter ablation was offered to 70% of patients with symptomatic paroxysmal or persistent AF after the failure or intolerance of 1 antiarrhythmic drug. All modifiable risk factors were documented in 59.3% of patients. Rates of all-cause mortality, ischemic stroke or transient ischemic attack, and major bleeding were 8.1, 0.8, and 2.56 per 100 patients/y, respectively. QIs for anticoagulation and outcomes were similar between general cardiology and tertiary referral centers.Conclusions Although accredited centers in Spain demonstrated good performance in many of the ESC QIs for AF, there remains room for improvement. These data could serve as a starting point for enhancing the quality of care in this population.

Morphology and Function Assessment of Left Atrial Appendage in Patients With Atrial Fibrillation

ABSTRACTAtrial fibrillation (AF) is among the most prevalent forms of clinically significant arrhythmia, and stroke incidence is among the most serious AF‐related complications, causing high rates of morbidity and mortality among affected patients. The European Society of Cardiology guidelines recommend a thromboembolic event risk assessment based on the CHA2DS2‐VASC score. However, stroke also occurs in some patients with a low CHA2DS2‐VASC score. Therefore, it is necessary to improve thromboembolic risk stratification in AF patients. The left atrial appendage (LAA) is considered to be the most frequent site of thrombus formation. Approximately 47% of thrombi in valvular AF and 91% of thrombi in nonvalvular AF are localized in the LAA. Therefore, identification or exclusion of LAA thrombi is critical in many clinical situations. It is essential to assess LAA morphology and function using imaging modalities (particularly echocardiography) before, during, and after interventional procedures such as AF ablation and LAA occlusion. This review article describes the anatomical, physiological, and LAA assessment in daily practice.

Radiofrequency catheter ablation of persistent atrial fibrillation in a patient with cor triatriatum sinister

Radiofrequency catheter ablation of persistent atrial fibrillation in a patient with cor triatriatum sinister

Anatomical-guided third-generation laser balloon ablation for the treatment of paroxysmal atrial fibrillation assessed by continuous rhythm monitoring: results from a multicentre prospective study.

The third-generation laser balloon (LB3) is an established ablation device for pulmonary vein isolation (PVI) that allows direct visualization of the anatomical target. Equipped with an automatic circumferential laser delivery modality, it aims at continuous circumferential PVI, improving both acute and clinical outcomes. We sought to evaluate the clinical efficacy of LB3 ablation using an anatomical-based approach without verifying electrical isolation. Among 257 paroxysmal AF patients undergoing LB3 ablation across four Italian centres, 204 (72% male, mean age 60.4 ± 11.1 years) were included. The primary endpoint was freedom from any atrial tachyarrhythmia (ATa) recurrence after the blanking period (BP), assessed with implantable cardiac monitors (ICMs). All pulmonary veins (PVs) were targeted using the LB3, with the RAPID mode used on an average of 96 ± 8, 86 ± 19, 98 ± 11, and 84 ± 15% for the left superior, left inferior, right superior, right inferior PV, and left common ostium, respectively. Freedom from arrhythmia recurrences was 84.8% at 1, 80.4% at 2, and 76.0% at 3 years. An ATa burden ≥ 5% was documented in 2.5, 4.4, and 5.4% at 1, 2, and 3 years, respectively. Relapses during the BP [hazard ratio (HR) = 2.182, P = 0.032] and left atrial dilation (HR = 1.964, P = 0.048) were independent predictors of recurrences. Anatomical-guided LB3 ablation for paroxysmal AF is a safe and effective approach, providing excellent clinical outcomes as assessed by ICM over nearly 3 years of follow-up.

Single-loop biatrial tachycardia mimicking typical atrial flutter in a patient without a history of cardiac surgery or ablation

Single-loop biatrial tachycardia mimicking typical atrial flutter in a patient without a history of cardiac surgery or ablation

Combined left atrial appendage occlusion and catheter ablation for atrial fibrillation versus isolated left atrial appendage occlusion: A systematic review and meta-analysis

Combined left atrial appendage occlusion and catheter ablation for atrial fibrillation versus isolated left atrial appendage occlusion: A systematic review and meta-analysis

Left Upper Lobectomy for Pulmonary Vein Occlusion after Catheter Ablation for Atrial Fibrillation

Left Upper Lobectomy for Pulmonary Vein Occlusion after Catheter Ablation for Atrial Fibrillation

Novel versus Established Cryoballoon Ablation System for Atrial fibrillation: A Systematic Review and Meta-Analysis

BackgroundRecently a novel cryoballoon ablation (CBA) system (POLARx) for the treatment of atrial fibrillation (AF) has been introduced. ObjectiveWe aimed at systematically reviewing the efficacy and safety of the POLARx to the ArcticFront system. MethodsStructured systematic database search for articles published between 2021 and 2024 reporting the efficacy and/or safety of the POLARx system for AF ablation. The co-primary endpoints were the long-term efficacy and safety of the POLARx system ResultsOf the 24 studies with 5364 patients (weighted mean age 62.4 years) included, 15 compared the POLARx system (1746 patients) to the ArcticFront system (2282 patients). Despite significantly lower temperatures at isolation (POLARx -46.3°C, ArcticFront -31.6°C, p <0.01) and nadir temperatures (POLARx -56.5°C ArcticFront -47.8°C p <0.01), the POLARx system did not show a better acute (98.9% and 99.2% successfully ablated patients, 99.5% and 99.8% successfully ablated pulmonary veins in the POLARx and ArcticFront group, respectively) or long-term efficacy (After a weighted mean follow-up of 12.6 months, the success rate was 69.5% with POLARx and 60.2% with ArcticFront (p = 0.98)). While most complications were similar between the POLARx and ArcticFront group, the incidence of phrenic nerve palsies in the pooled cohorts (all POLARx vs all ArcticFront control patients) differed (2.7% vs. 1.6% in the POLARx vs. ArcticFront group, respectively, OR 1.79 [1.14-2.83], p-value = 0.01). ConclusionThe novel POLARx system provided similar efficiency and acute/long-term efficacy, but showed a higher incidence of phrenic nerve palsies compared to the ArcticFront system.

Does atrial fibrillation ablation prevent cardiovascular death, stroke, and heart failure events?

Does atrial fibrillation ablation prevent cardiovascular death, stroke, and heart failure events?

Left Internal Thoracic Artery Injury in Percutaneous Epicardial Access for Catheter Ablation: Prevention and Management

Left Internal Thoracic Artery Injury in Percutaneous Epicardial Access for Catheter Ablation: Prevention and Management

Wave speed mapping visualizes the cavotricuspid isthmus reconnection area: A case report.

In addition to the reentrant map, the wave speed map can be helpful in accurately identifying the CTI gap during radiofrequency application for atrial flutter(AFL). However, in complex cases involving extensive scarring and multiple low-velocity local areas, this technique may not be useful. A 73-year-old male patient with a history of pulmonary vein isolation and cavotricuspid isthmus ablation underwent a second catheter ablation owing to recurrent atrial flutter (AFL). The AFL was diagnosed as cavotricuspid isthmus-dependent AFL caused by the reconnection of the previous cavotricuspid isthmus ablation. Wave speed mapping was performed at the same site, and results comprehensively revealed a low-velocity local area. The AFL was terminated after the first radiofrequency application, and the block line was easily completed. Therefore, this technique could be an adjunctive tool for cavotricuspid isthmus gap identification and minimal radiofrequency application.

Predictors of long‐term success after high‐density mapping‐guided substrate ablation procedures for ventricular tachycardia in patients with ischemic cardiomyopathy

AbstractIntroductionHigh‐density (HD) substrate mapping may increase success of catheter ablation targeting ventricular tachycardia (VT). However, despite its use, recurrent VT is not uncommon. We aim to investigate factors that are associated with outcomes after HD mapping‐guided substrate ablation procedures for VT in patients with ischemic cardiomyopathy.MethodsObservational cohort study includes patients with ischemic heart disease who underwent HD mapping‐guided substrate ablation of VT. Baseline and procedural characteristics were associated with outcomes after VT ablation.ResultsVT ablation employing HD mapping was performed in 80 patients. Median follow‐up was 2.3 years. VT‐free survival at one, two, and five years were 65%, 49%, and 40%. One‐, two‐, and five‐year implantable cardioverter defibrillator (ICD) shock‐free survival rates were 90%, 81%, and 70%. Complications occurred in 3 patients (3.8%, 1 vascular, 2 tamponades). Left ventricular ejection fraction (LVEF) and 45 W (vs. 35 W) ablation power were associated with VT‐free survival. High ablation power was also associated with shock‐free survival. All‐cause mortality during follow‐up was associated with higher age, the presence of chronic obstructive pulmonary disease (COPD), LVEF, and urgent ablation.ConclusionsIn patients with ischemic cardiomyopathy that had HD substrate mapping‐guided VT ablation, ablation power was associated with both VT‐free and shock‐free survival, underlining the importance of effective target elimination. All‐cause mortality during follow‐up was associated with several factors (age, COPD, LVEF, and urgent vs. elective ablation), which could be used to guide patient selection for VT ablation.

Mapping and Ablation of left atrial macro-reentrant tachycardia with a novel circular pulsed field ablation catheter

Mapping and Ablation of left atrial macro-reentrant tachycardia with a novel circular pulsed field ablation catheter

Invasive strategies for rhythm control of atrial fibrillation: a narrative review.

Atrial fibrillation (AF) is the most common sustained tachyarrhythmia and its increasing prevalence has resulted in a growing healthcare burden. A recent landmark randomized trial, the EAST-AFNET 4 (Early Treatment of Atrial Fibrillation for Stroke Prevention Trial), highlighted the importance of early rhythm control in AF, which was previously underemphasized. Rhythm control therapy includes antiarrhythmic drugs, direct-current cardioversion, and catheter ablation. Currently, catheter ablation is indicated for patients with AF who are either refractory or intolerant to antiarrhythmic drugs or who exhibit decreased left ventricular systolic function. Catheter ablation can be categorized according to the energy source used, including radiofrequency ablation (RFA), cryoablation, laser ablation, and the recently emerging pulsed field ablation (PFA). Catheter ablation techniques can also be divided into the point-by-point ablation method, which ablates the pulmonary vein (PV) antrum one point at a time, and the single-shot technique, which uses a spherical catheter to ablate the PV antrum in a single application. PFA is known to be applicable to both point-by-point and single-shot techniques and is expected to be promising owing to its tissue specificity, resulting in less collateral damage than catheter ablation involving thermal energy, such as RFA and cryoablation. In this review, we aimed to outline catheter ablation for rhythm control in AF by reviewing previous studies.

Drug therapy and catheter ablation for management of arrhythmias in continuous flow left ventricular assist device's patients. A Clinical Consensus Statement of the European Heart Rhythm Association and the Heart Failure Association of the ESC.

Left ventricular assist devices (LVADs) are an increasingly used strategy for the management of patients with advanced heart failure. Although these devices effectively improve survival, atrial and ventricular arrhythmias are common with a prevalence of 20-50% at one year after LVAD implantation. Arrhythmias predispose these patients to additional risk and are associated with considerable morbidity from recurrent implantable cardioverter-defibrillator (ICD) shocks, progressive failure of the unsupported right ventricle, and herald an increased risk of mortality. Management of patients with arrhythmias and LVAD differs in many aspects from the general population heart failure patients. These include ruling out the reversible causes of arrhythmias that in LVAD patients may include mechanical irritation from the inflow cannula and suction events. For patients with symptomatic arrhythmias refractory to medical treatment, catheter ablation might be relevant. There are specific technical and procedural challenges perceived to be unique to LVAD-related ventricular tachycardia ablation such as vascular and LV access, signal filtering, catheter manoeuvrability within decompressed chambers, and electroanatomic mapping system interference. In some patients, the arrhythmogenic substrate might not be readily accessible by catheter ablation after LVAD implantation. In this regard, the peri-implantation period offers a unique opportunity to surgically address arrhythmogenic substrate and suppress future ventricular tachycardia recurrences. This document aims to address specific aspects of the management of arrhythmias in LVAD patients focusing on anti-arrhythmic drug therapy and ablations.

Left atrial functional changes associated with repeated catheter ablations for atrial fibrillation.

The impact of repeated atrial fibrillation (AF) ablations on left atrial (LA) mechanical function remains uncertain, with limited long-term follow-up data. This retrospective study involved 108 AF patients who underwent two catheter ablations with cardiac magnetic resonance imaging (MRI) done before and 3 months after each of the ablations from 2010 to 2021. The rate of change in peak longitudinal atrial strain (PLAS) assessed LA function. Additionally, a sub-study of 36 patients who underwent an extra MRI before the second ablation, gave us an additional time segment to evaluate the basis of change in PLAS. In the two-ablation, three MRI sub-study 1, the PLAS percent change rate was similar before and after the first ablation (r11 = -0.9 ± 3.1%/year, p = 0.771). However, the strain change rate from postablation 1 to postablation 2 was significantly worse (r12 = -23.7 ± 4.8%/year, p < 0.001). In the sub-study 2 with four MRIs, all three rates were negative, with reductions from postablation 1 to pre-ablation 2 (r22 = -13.3 ± 2.6%/year, p < 0.001) and from pre-ablation 2 to postablation 2 (r23 = -8.9 ± 3.9%/year, p = 0.028) being significant. The present study suggests that the more ablations performed, the more significant the decrease in the postablation mechanical function of the LA. The natural progression of AF (strain change from postablation 1 to pre-ablation 2) had a greater negative influence on LA mechanical function compared to the second ablation itself suggesting that second ablation in patients with recurrence after first ablation is an effective strategy even from the LA mechanical function aspect.

An anthropomorphic phantom for atrial transseptal puncture simulation training

BackgroundTransseptal puncture (TSP) is a critical prerequisite for left-sided cardiac interventions, such as atrial fibrillation (AF) ablation and left atrial appendage closure. Despite its routine nature, TSP can be technically demanding and carries a risk of complications. This study presents a novel, patient-specific, anthropomorphic phantom for TSP simulation training that can be used with X-ray fluoroscopy and ultrasound imaging.MethodsThe TSP phantom was developed using additive manufacturing techniques and features a replaceable fossa ovalis (FO) component to allow for multiple punctures without replacing the entire model. Four cardiologists and one cardiology trainee performed TSP on the simulator, and their performance was assessed using four metrics: global isotropy index, distance from the centroid, time taken to perform TSP, and a set of 5-point Likert scale questions to evaluate the clinicians’ perception of the phantom’s realism and utility.ResultsThe results demonstrate the simulator’s potential as a training tool for interventional cardiology, providing a realistic and controllable environment for clinicians to refine their TSP skills. Experienced cardiologists tended to cluster their puncture points closer to regions of the FO associated with higher global isotropy index scores, indicating a relationship between experience and optimal puncture localization. The questionnaire analysis revealed that participants generally agreed on the phantom’s realistic anatomical representation and ability to accurately visualize the TSP site under fluoroscopic guidance.ConclusionsThe TSP simulator can be incorporated into training programs, offering trainees the opportunity to improve tool handling, spatial coordination, and manual dexterity prior to performing the procedure on patients. Further studies with larger sample sizes and longitudinal assessments are needed to establish the simulator’s impact on TSP performance and patient outcomes.

Computed Tomography Confirms Increased Left Atrial Volume in Patients with Bayés Syndrome Referred for Catheter Ablation of Atrial Fibrillation

Background: Bayés syndrome is a recently identified condition that is defined by the presence of an interatrial block on a surface electrocardiogram, in addition to atrial arrhythmias such as atrial fibrillation, tachycardia, or left atrial flutter. This syndrome is linked to an increased risk of stroke, morbidity, and mortality. An interatrial block is a conduction delay between the right atrium and left atrium and can be recognized by a P wave duration &gt;120 ms. It is known that P wave duration can estimate the size of the left atrium measured via echocardiography, which is a marker for stratifying cardiovascular risk. Our study aims to verify whether the duration of the P wave can estimate the volume of the left atrium measured by computed tomography in patients with an interatrial block. Methods: We included 105 patients with a sinus rhythm and a partial or advanced interatrial block (IAB) who underwent contrast-enhanced cardiac computed tomography (CT). The mean age was 62.2 ± 10.1 years, and 38% of the patients were women. Results: The mean P wave duration was 122.6 ± 11.4 ms in the partial IAB group and 150 ± 8.4 ms in the advanced IAB group (p &lt; 0.01). The mean left atrial volume was 115 ± 39 mL in the partial IAB group and 142 ± 34 mL in the advanced IAB group (p = 0.001). P wave duration was longer in patients with an advanced as opposed to partial interatrial block. Left atrial volume and LAVI were higher in patients with an advanced as opposed to partial interatrial block. Conclusions: All the patients (100%) with an advanced IAB had a dilated left atrium. P wave duration can accurately estimate LA volume in patients with an IAB using the formula: LA volume = 0.6 × P wave + 46 mL.

Sacubitril-Valsartan Lowers Atrial Fibrillation Recurrence and Left Atrial Volume Post-catheter Ablation: Systematic Review and Meta-Analysis.

In patients with atrial fibrillation (AF) who have undergone catheter ablation, the comparative effectiveness of sacubitril-valsartan (SV) versus ACE inhibitors (ACEi) or angiotensin-receptor blockers (ARB) in preventing AF recurrence remains unclear. The purpose of the present systematic review and meta-analysis is to determine whether SV offers superior outcomes in this clinical setting. This study systematically reviewed PubMed, Embase, and the Cochrane Library for randomized controlled trials (RCTs) and propensity-matched cohorts (PMC), evaluating SV's efficacy in preventing AF recurrence after catheter ablation. Outcomes included AF recurrence and structural remodeling assessed via left ventricular ejection fraction (LVEF) and left atrial volume index (LAVi), with statistical analyses performed using Review Manager 5.1.7 and heterogeneity assessed via I2 statistics. The analysis comprised 642 patients from three RCTs and one PMC (319 SV-treated). SV significantly reduced AF recurrence [risk ratios (RR) 0.54; 95% confidence intervals (CI) 0.41-0.70; p < 0.00001; I2 = 0%), a trend also observed when considering RCTs exclusively (RR 0.58; 95% CI 0.41-0.84; p = 0.004; I2 = 0%). Moreover, SV demonstrated a notable reduction in LAVi [mean deviation (MD) -5.34 mL/m2; 95% CI -8.77 to -1.91; p = 0.002; I2 = 57%] compared with ARB, alongside a significant improvement in LVEF (MD 1.83%; 95% CI 1.35-2.32; p < 0.00001; I2 = 0%). Subgroup analyses among patients with hypertension and LVEF < 50% also indicated lower AF recurrence with SV. SV therapy exhibited superior efficacy in reducing AF recurrence compared with ACEi or ARB and demonstrated superior outcomes in attenuating atrial structural remodeling after catheter ablation. These findings underscore the potential of SV as a therapeutic option for patients with AF undergoing catheter ablation, highlighting its efficacy in mitigating AF recurrence and structural remodeling. PROSPERO identifier number CRD42024497958.