Atrial Fibrillation Ablation Procedures Research Articles

Abstract 4118804: Use and Clinical Outcomes Associated with Urgent versus Elective Catheter Ablation of Atrial Fibrillation in the United States

Introduction: Catheter ablation of atrial fibrillation (AF) is an increasingly important evidence-based treatment option for select patients. Although typically performed as an outpatient elective procedure, the use and clinical outcomes of AF ablation pursued urgently among inpatients have not been adequately characterized. Hypothesis: Rate of urgent AF ablation, defined as an AF ablation procedure pursued among inpatients hospitalized for a non-procedural indication, has increased over time, and may be associated with worse outcomes. Aims: To describe the use and outcomes of urgent versus elective AF ablation. Methods: Using the NCDR AFib Ablation Registry, patients who underwent AF ablation from 1/1/2016 to 6/30/2023 were stratified according to whether AF ablation was urgent or elective. Logistic regression models were fitted to determine patient and hospital-level factors associated with use of urgent AF ablation. Cochrane-Armitage tests were used to test for trends over time. Unadjusted and adjusted in-hospital event rates were reported. Results: Among 140,051 patients, 2,714 (1.9%) underwent urgent inpatient AF ablation and 137,337 (98.1%) elective ablation. Compared with the elective cohort, those undergoing urgent ablation had higher rates of co-morbid conditions including: diabetes (30.6% vs. 20.4%, P<0.0001), coronary artery disease (30.8% vs. 22.7%, P<0.0001), and heart failure (47.1% vs 20.8%, P<0.0001). Urgent AF ablation was more often used among patients of Black race (OR 1.68; 95% CI: 1.41 – 2.0) and those with AF at the time of the procedure (OR 1.73; 95% CI: 1.36 – 2.20). Higher hospital procedural volume of AF ablations ([per 100 cases] OR 1.22; 95% CI: 1.20 – 1.25) was also associated with higher odds of urgent AF ablation. The use of urgent AF ablation increased from 0.5% in 2016, to 2.0% in 2023 (P<0.0001). Unadjusted event rates for AF-related complications were significantly higher for the urgent cohort (Figure). The adjusted rate of any procedure-related complication was significantly higher in the urgent cohort (urgent 4.9% vs. elective 2.4%, P<0.0001). Conclusions: The rate of urgent inpatient AF ablation has increased over time. Compared with elective AF ablation, after adjustment for patient risk factors, urgent AF ablation is associated with significantly higher rates of procedural complications. Use of urgent, inpatient AF ablation should be carefully considered within clinical contexts and offered to select patients.

Abstract 4125059: Techniques and Outcomes of Atrial Fibrillation Ablation in Patients with Persistent Left Superior Vena Cava

Introduction/Background: Persistent Left Superior Vena Cava (PLSVC) presents unique challenges for atrial fibrillation (AF) ablation due to its arrhythmogenic potential and complex anatomical variations. Understanding tailored approaches and outcomes in patients with PLSVC and AF is essential for improving procedural success and safety. Research Questions/Hypothesis: This study aims to investigate the efficacy and outcomes of tailored ablation strategies in patients with PLSVC and AF. Goals/Aims: To evaluate the procedural safety, acute success, and AF recurrence rate post-ablation in patients with PLSVC, and to determine the optimal ablation strategies for this population. Methods/Approach: This retrospective cohort study included 16 patients with PLSVC who underwent 21 AF ablation procedures between August 1, 2008, and February 14, 2024, at the Hospital of the University of Pennsylvania. Procedures involved pre-ablation imaging, 3D electroanatomical mapping, pulmonary vein isolation (PVI), and targeted ablation strategies focusing on PLSVC-related triggers. The primary endpoints were procedural safety and AF recurrence post-ablation. Results/Data: The cohort's mean age was 51.9 ± 17.9 years, 31.2% of whom were female. Triggers from the PLSVC were identified in 66.7% of procedures. Tailored ablation strategies were employed to isolate PLSVC-left atrium/coronary sinus connections or directly target the induced triggers, with a success rate of 85% in achieving isolation or targeted ablation once triggers were induced. The recurrence rate of arrhythmia post-ablation was 58.3% in the patient-based analysis and 70.6% in the procedure-based analysis. No major complications occurred. Conclusion(s): This study highlights the significance of recognizing PLSVC as a potential source of AF triggers. The single procedure success rate is low compared to patients without PLSVC. Further studies are warranted to enhance outcomes in this challenging AF population.

Techniques and outcomes of atrial fibrillation ablation in patients with persistent left superior vena cava.

To investigate tailored approaches, techniques, and outcomes of catheter ablation in patients with persistent left superior vena cava (PLSVC) undergoing atrial fibrillation (AF) ablation. PLSVC presents unique challenges for AF ablation due to its potential as an arrhythmogenic source and the complex anatomical variations it introduces. The retrospective cohort included 16 patients with PLSVC that underwent 21 AF ablation procedures between August 1, 2008, and February 14, 2024, at the Hospital of the University of Pennsylvania. Procedures involved pre-ablation imaging, 3D electroanatomical mapping, pulmonary vein isolation, and targeted ablation strategies focusing on the PLSVC-related ablation. The primary endpoints were procedural safety and AF recurrence postablation. The cohort's mean age was 51.9 ± 17.9 years, 31.2% of whom were female. Triggers from the PLSVC were identified in 66.7% of procedures. Tailored ablation strategies were employed to isolate PLSVC-left atrium/coronary sinus connections or directly target the induced triggers, with a success rate of 85% in achieving isolation or targeted ablation once triggers were induced. The recurrence rate of arrhythmia postablation was 46.7% in the patient-based analysis and 65% in the procedure-based analysis. No major complications occurred. This study highlights the significance of recognizing PLSVC as a potential source of AF triggers. The single procedure success rate is low compared to patients without PLSVC. Further studies are warranted to enhance outcomes in this challenging AF population.

Left Atrial Structure and Function Following Ethanol Infusion into Vein of Marshall (MR-SHALL Study).

Ethanol infusion into the vein of Marshall (EI-VOM) is an adjunctive therapy to pulmonary vein isolation (PVI), which improves the efficacy of persistent atrial fibrillation (AF) ablation procedures. It is unknown how EI-VOM scar formation impacts left atrium (LA) structure and function. To characterize scar formation after EI-VOM, and its impact on LA function, by cardiac magnetic resonance (CMR). Consecutive patients referred for persistent AF ablation, or any repeat procedure, were included. Ablation strategy included PVI, EI-VOM and linear lesions when deemed necessary. LA was assessed by late gadolinium enhancement (LGE) CMR at baseline and 3-month follow-up. CMR was post-processed off-line with dedicated software. The LA was regionalized into 17 segments, and global and regional scarring were calculated. Strain parameters were analyzed-including LA reservoir, conduit, and booster strain; LA ejection fraction; and LA passive and active emptying function. Follow-up LGE-CMR reconstruction was coregistered with the voltage map, ablation RF points, and fluoroscopy to compare the scar location with the VOM trajectory. This study included 21 patients (65 ± 8 years; 76% men; 57% ablation of persistent AF). After EI-VOM, 95% of patients presented new low-voltage areas, all of whom exhibited new LGE-CMR scarring at follow-up. Voltage map and LGE-CMR coregistration showed comparable scar areas (p = 0.287). LGE-CMR scarring frequently involved the whole VOM trajectory, predominantly affecting the LA ridge, mitral isthmus, and left posterior wall. LA volume was significantly reduced after ablation, without significant changes in LA functional parameters. EI-VOM causes permanent scarring at 3-month follow-up, with no adverse impact on CMR LA functional parameters.

Comparative Influences of Beta blockers and Verapamil on Cardiac Outcomes in Hypertrophic Cardiomyopathy

Guidelines recommend β blockers (BBs) as first-line therapy in symptomatic patients with hypertrophic cardiomyopathy (HCM) and nondihydropyridine calcium channel blockers, particularly, verapamil, as the second-line therapy, despite the absence of comparison trials between those 2 drugs. Because deleterious effects of verapamil have been reported in this setting, the present analysis aimed to evaluate the prognostic impact of BBs and verapamil in a cohort of patients with HCM. From a nationwide cohort of 1,434 patients with a diagnosis of HCM included in the French prospective observational REgistry of hypertrophic cardioMYopathy (REMY), we retrospectively analyzed patients with sarcomeric HCM included in the 3 largest centers and treated either with BBs or verapamil. Patients with a cardiac defibrillator or a pacemaker or who underwent a procedure of atrial fibrillation or septal ablation were excluded. The primary end point was the composite of cardiovascular death, hospitalization for heart failure, and hospitalization for atrial fibrillation. Of 600 patients with HCM, 544 (91%) were treated with BBs and 56 (9%) with verapamil. At inclusion, the 2 groups were comparable concerning the presence/amplitude of obstruction and sudden cardiac death risk factors. At up to 8 years of follow-up (median 3.9 years, interquartile range 2.1 to 5.8), no significant differences were observed in the primary end point (132 [24%] vs 10 [18%] under BBs or verapamil, respectively, hazard ratio 1.84, 95% confidence interval 0.94 to 3.63). In conclusion, in a real-world cohort of low-risk patients with HCM, verapamil therapy was not associated with a higher incidence of adverse events than β-blocker therapy.

Risk factors for procedure-related complications in very elderly patients undergoing atrial fibrillation ablation: analysis from the Japan Ablation Registry

Abstract Background As atrial fibrillation (AF) ablation procedures become increasingly prevalent, understanding the risks of procedure-related complications is crucial, particularly in the very elderly population, defined in this context as patients aged 80 years and above. This study aimed to identify risk factors for complications in this demographic. Methods We conducted a prospective analysis of 170,017 AF ablation procedures from the Japan Ablation Registry, covering 482 facilities between 2017 and 2020. The analysis focused on patients aged 80 or older (very elderly group, n=14,389). Multivariate analysis was employed to identify risk factors for procedure-related complications in the very elderly, incorporating factors that showed a p-value of less than 0.1 in univariate analysis. Results Procedure-related complications were observed in 3.62% of the very elderly group. The multivariate analysis (Model 1) identified significant risk factors were the initial procedure (OR 1.30, 95% CI 1.01-1.67, p=0.041), type of AF (OR 1.34, 95% CI 1.03-1.74), and body weight (OR 0.99, 95% CI 0.98-1.00, p=0.082). For further analysis, the type of AF was categorized into paroxysmal AF (PAF), persistent AF (PeAF) and long-standing PeAF. We included these categories, along with the initial procedure and body weight, into further multivariate analysis (Model 2), which revealed that long-standing PeAF (OR 1.34, 95% CI 1.03-1.74, p=0.032), initial ablation (OR 1.30, 95% CI 1.01-1.67, p=0.042) and body weight (OR 0.99, 95% CI 0.98-0.99, p=0.001) were independently and significantly associated with complications. Conclusion This study identifies initial procedures, low body weight, and long-standing PeAF as significant risk factors for procedure-related complications in very elderly patients undergoing AF ablation. These findings highlight the importance of careful patient selection and tailored procedure planning for these subgroups in the very elderly population.

A multi-center retrospective cohort analysis of age and racial disparities in patients undergoing repeat ablation for recurrent atrial fibrillation

Abstract Introduction Atrial fibrillation (AF) is the most common type of cardiac arrhythmia, and its prevalence has been increasing worldwide. Current data shows that AF is more common in white males compared to blacks despite blacks having multiple cardiovascular comorbidities. There is paucity of data showing the recurrence of AF re-ablation after index ablation specifically as it pertains to race, gender, and age. We sought to explore the rates of recurrent AF re-ablation in this retrospective cohort analysis. Methods Using a multi-center database, we examined 23,558 encounters and 10,530 had readmission records i.e. readmitted within 3 years. The encounters included adults (18+) who had an ablation procedure for atrial fibrillation between 1/1/2018-06/30/2020. We used binary logistic regression models and Tukey-Kramer procedure to analyze pairwise comparisons among different subgroups of race, sex, and age group. The primary endpoint was recurrence of repeat ablation. Secondary endpoints included non-fatal stroke and myocardial infarction. Results Our sample size was 23,558 patients, 20,276 were white patients (86%) and 3,282 were non-white patients (14%). The average age was 66.29 years (SD 10.43) and average age at the time of repeat ablation was 65.97 years. The average BMI was 21.55. Out of the 23,558 patients, 14.30% (N= 3368) had re-ablation within 3 years of the index ablation. The odds ratio of re-ablation for patients in their 50s is 1.4229 (95% CI [1.1172, 1.8122]) compared to patients in their 80s. Similarly, the odds ratio is 1.4330 (95% CI [1.1466, 1.7909]) for the 60-69 group, 1.3075 (95%CI [1.0458, 1.6346]) for the 70-79 group and 1.3443 (95% CI [1.0088, 1.7914]) for patients below 50 compared to over 80 group. The LR for re-ablation was 0.8438 (p=0.3583) in females. The incidence of non-fatal stroke and MI were 0.27% (N= 63) and 0.19% (N= 45). Average length of time to re-ablation was 415.5 days. Discussion When controlling for age group and sex, race was not significantly associated with an increased likelihood of repeat ablation. When controlling for race and age group, sex was not significantly associated with an increased likelihood of repeat ablation. When controlling for race only, females were not at a higher risk of re-ablation. However, when controlling for race and sex, patients in their 50s are 42.3% more likely to have re-ablation when compared to patients in their 80s. In contrast, the age of patients at their first ablation increased, there appeared to be a rising trend indicating a higher chance of AF recurrence within 3 years when controlling for race and sex. Conclusion The incidence of repeat AF ablation is not higher in racial minorities when compared to whites. Interestingly, there appears to be an decreasing rate of AF re-ablation in older patients despite a higher rate of AF recurrence as age increases possibly owing to more conservative therapeutic approach such as medical management.

Age-related and age-independent complications in atrial fibrillation ablation: insights from the Japan ablation registry

Abstract Background The growing prevalence of atrial fibrillation (AF) has intensified the focus on managing this condition in the elderly. Catheter ablation, a popular treatment option, requires more detailed examination due to limited data on its efficacy and risks in this age group. Aim To identify the types of complications of AF ablation correlated with advanced age and to differentiate them from age-independent complications. Method We conducted a prospective analysis of 170,017 AF ablation procedures from the Japan ablation registry, conducted across 482 facilities between 2017 and 2020. Complications in patients aged 80 and above (elderly group, n=14,389) were compared with those under 80 (control group, n=155,628). The overall complication rate was 2.77%, with a higher occurrence in the elderly group (elderly group vs. control group, 3.62% vs. 2.69%, p<0.001). Notably, the elderly experienced more cardiac tamponade/pericardial effusion (0.95% vs. 0.6%, p<0.001), symptomatic cerebral infarction or transient ischemic attacks (0.27% vs. 0.15%, p=0.001), and sick sinus syndrome (0.31% vs. 0.05%, p<0.001). While in-hospital mortality in the elderly group was relatively low (0.16%), it was significantly higher compared to the control group (0.06%, p<0.001). However, incidences of other complications like puncture-site complications (0.49% vs. 0.42%, p=0.28), non-puncture-site bleeding, esophagus-related complications (0.22% vs. 0.22%, p=0.72), and phrenic nerve palsy (0.44% vs. 0.43%, p=0.69) showed no significant age-related differences. Conclusion Elderly patients undergoing AF ablation are at a higher risk of overall complications, with particular susceptibility to cardiac tamponade/pericardial effusion, symptomatic cerebral infarction/transient ischemic attacks, and sick sinus syndrome. This highlights the need for careful monitoring of these specific complications in the elderly. Additionally, it is noteworthy that the risk of certain complications appears to be independent of age.

Prevalance of incessant form of atrial fibrillation by superior vena cava (svc) firing:simplified svc and sinus node mapping(sss map) to avoid sinus node injury

Abstract Background The superior vena cava (SVC) is known as a major source of atrial fibrillation(AF), non-pulmonary vein AF foci (NPVAF). In some cases, an incessant form of AF (iAF) by SVC firing prevents obtaining the sinus node location, and anatomical SVC isolation has a risk of sinus node injury (SNI). Objective This study was aimed to explore the frequency of iAF by SVC firing and the efficacy of the simplified mapping strategy to avoid SNI. Methods Consecutive AF ablation procedures in the 3 centers were retrospectively investigated including the NPVAF prevalence. Simplified SVC/SN mapping (SSS-map: Obtaining the top-end of the SVC potential and >4points with 5-10mm spacing in the upper lateral side of the right atria (RA) for roughly locating the earliest activation site in sinus rhythm) was performed before PV isolation in the last 138 patients. In case of the initial rhythm at the procedure was atrial fibrillation, cardioversion was performed for obtaining the SSS-map. In the cases in which the high-density mapping catheters were available, the high-density activation maps of the RA in sinus rhythm were obtained to investigate the dislocation of the earliest activation site of the SSS map from the SN location. When SVC isolation was required due to iAF, SVC isolation line was designed based on the location of the top-end of the SVC potential during AF and ablative linear lesions were created to keep the distance of 5-10 mm above the second earliest activation site. Results A total of 1160 procedures in 1089 patients (male: 736[63.4%], age: 69.9, paroxysmal AF: 544[49.9%], first session: 997[85.9%]) was investigated. Prevalence of NPVAF was revealed in 160 of the all procedures (13.7%) (the SVC: 64, the posterior wall of the left atria: 24, the coronary sinus: 19, and others: 53). 16 of 160 NPVAFs (10.0%) developed to iAF by SVC firing. The SSS-map was successfully obtained in all of the last 138 patients (Initial rhythm at the procedure: AF 43.7%, Mapping time: 1.3±0.6 min, number of obtained points: 8.4±1.3). In 21 patients in which the high-density RA map was obtained, the SN dislocation distance was 5.1±2.2mm between the SSS map and the high-density RA map. Five of 138 developed to iAF by SVC firing, and SVC isolation based on the SSS-map was successfully achieved without SNI in the cases. Conclusion This study indicated iAF driven by SVC firing after PV isolation occurred in certain number of patients. The SSS-map before PV isolation was practical and showed the potential to be the mapping strategy avoid the SN injury in such cases.

Digital health in the EP lab: routine implementation of remote access and technical support for complex ablation procedures

Abstract Background Complex electrophysiological procedures are performed using three-dimensional (3D) electroanatomical mapping (EAM) systems, which are usually operated on site, by field technical engineers (FTE). Due to a lack of skilled personnel, the engineers usually must travel between different hospitals and the procedures have to be planed in advance. Remote access (RA) technologies were recently implemented in clinical practice, aiming to increase the flexibility in the EP lab and maximise healthcare resources use. Methods Electroanatomical mapping was performed remotely by means of an integrated audio-visual solution for RA. The operator and the FTE communicated exclusively using the RA system, while the latter worked only in home office. Consecutive procedures were prospectively enrolled and analysed in terms of indication, procedural characteristics, feasibility and saved travelled time by the FTA. Results Between September 2022 and July 2023, a total of 133 EP procedures were performed in a high volume, tertiary electrophysiological centre in Germany. The mean age was 67 (57.5, 75.5) years. Women represented 39.8% of the population. The median BMI was 26.2 (23.1, 30.3) Kg/m2. A total of 56 (42.1%) patients underwent an atrial fibrillation ablation procedure (37.5% paroxysmal), 22 (16.5%) an atrial tachycardia ablation, 13 (9.8%) cavotricuspid isthmus ablation, 15 (11.3%) supraventricular tachycardia ablation, 14 (10.5%) a premature ventricular contraction ablation, 12 (9%) ventricular tachycardia ablations and 1 patient an electrophysiological diagnostic study. The median time length of procedure was 130 (96.5, 168) minutes. The median number of radiofrequency applications was 63.5 (22.3, 109.5), while the median RF time was 14.2 (6.9, 25.1) minutes. The fluoroscopy time was 9.2 (6.5, 12.6) minutes, with a median radiation dose of 408.5 (233.0, 631.8) cGy x cm2. The median amount of contrast media was 40 (8.75, 50.0) ml and the median amount of heparin administered was 12000 (8000, 16000) UI. Protamine was used in 9 cases, with a median of 7000 (5000, 7000) UI. Except for one supraventricular procedure, where no arrhythmia induction was possible, all procedures were successful. One major complication was observed. In one case, the internet-based headphone connection was not stable. Therefore, the communication was established via a conventional smartphone. No change to on-site support was needed. The travel time reduction was available in 130 cases. In total, 290 travel hours could be saved. Conclusion The routine implementation of RA for complex EP procedures proved to be safe and efficient. This approach has the potential to increase the feasibility in case of emergency procedures, reduce travel times for FTE and streamline healthcare resources allocation.

Temporal trends of catheter ablation procedures in patients with atrial fibrillation and atrial flutter: A nationwide cohort study

BackgroundCatheter ablation is a well-established treatment to prevent atrial fibrillation (AF) and atrial flutter (AFL) recurrences and to relieve symptoms, whereas pacemaker implantation and atrioventricular node (AVN) ablation is used for rate control when medical therapy fails. AimsWe investigated temporal trends and patient characteristics in catheter ablation procedures for AF, AFL and AVN in Finland between 2012–2018. MethodsFinnish AntiCoagulation in Atrial Fibrillation (FinACAF) is a registry-based study including all patients with AF or AFL in Finland between 2012–2018. ResultsThe number of patients with AF or AFL diagnosis in Finland increased from 185057 to 243802 between 2012–2018 and a total of 8954 first-time catheter ablation procedures were performed. Of them, 4909 (54.8 %) were AF ablations, 2731 (30.5 %) AFL ablations and 1314 (14.7 %) AVN ablations. The procedural numbers increased from 457/year to 934/year for AF, from 223/year to 553/year for AFL and from 114/year to 238/year for AVN. Altogether, 0.65% of all patients with diagnosed AF or AFL underwent AF, AFL or AVN ablation in 2018. The mean age of the patients increased in all ablation groups. Patients undergoing AF and AFL ablations were predominantly men (69.7 % and 74.6 % respectively) whereas patients undergoing AVN ablation were more often women (56.9%). ConclusionsThe use of catheter ablation more than doubled during 2012–2018 and the increase was particularly seen in the elderly patients. Nevertheless, only a minority of AF and AFL patients were treated with catheter ablations.

Surveillance of esophageal injury after atrial fibrillation catheter ablation.

Atrial-esophageal fistula following ablation procedures for atrial fibrillation (AF) remains a major concern. There is no standardized approach to minimize the risk and morbidity of this serious complication. The objective of this study was to present the 7-year experience of systematic endoscopic surveillance of esophageal injury after AF catheter ablation. This was a retrospective single-center registry of systematic endoscopic evaluations after consecutive AF ablation procedures performed from 2016 to 2022. A total of 677 AF ablation procedures with controlled esophagogastroduodenoscopy (EGD) were analyzed during that period. Most patients were male (71%) with paroxysmal AF (71%). Radiofrequency with electroanatomical mapping was the main ablation approach for 633 patients (93.5%). Esophageal temperature monitoring was performed using a single sensor in 220 patients (34.3%) and a multisensor probe in 296 patients (46%). Most of the patients presented no esophageal lesions (75,7%). Severe lesions (Kansas-city-classification KCC 2B) were found in 46 (6.8%) of them, requiring a new EGD in 7days. KCC2B lesions were persistent in 3 patients, 2 of whom had ulcers during healing and 1 patient with a deep ulcer of 10mm who was admitted to the hospital and underwent fasting and parenteral nutrition. The ulcer healed in the second week after the procedure. Both esophageal temperature monitoring strategies were equivalent at preventing thermal lesions. Additionally, a greater left atrium (LA) was associated with a lower incidence of esophageal ulcer (P = 0.028). Most of the lesions spontaneously healed. The incidence of esophageal injury after ablation was 24.3%. Most (72%) were mild lesions that required no therapeutic intervention. A larger left atrium (LA) was correlated with a lower incidence of thermal lesions. Early endoscopy can help diagnose severe esophageal lesions and may provide additional information for the surveillance of esophageal injury after AF ablation.

Atrioventricular node ablation for atrial fibrillation in the era of conduction system pacing.

Despite key advances in catheter-based treatments, the management of persistent atrial fibrillation (AF) remains a therapeutic challenge in a significant subset of patients. While success rates have improved with repeat AF ablation procedures and the concurrent use of antiarrhythmic drugs, the likelihood of maintaining sinus rhythm during long-term follow-up is still limited. Atrioventricular node ablation (AVNA) has returned as a valuable treatment option given the recent developments in cardiac pacing. With the advent of conduction system pacing, AVNA has seen a revival where pacing-induced cardiomyopathy after AVNA is felt to be overcome. This review will discuss the role of permanent pacemaker implantation and AVNA for AF management in this new era of conduction system pacing. Specifically, this review will discuss the haemodynamic consequences of AF and the mechanisms through which 'pace-and-ablate therapy' enhances outcomes, analyse historical and more recent literature across various pacing methods, and work to identify patient groups that may benefit from earlier implementation of this approach.

Prediction of major intravascular hemolysis during pulsed electric field ablation of atrial fibrillation using a pentaspline catheter.

Pulsed electric field (PEF) has emerged as a promising energy source for catheter ablation of atrial fibrillation (AF). However, data regarding the in-vivo effect of PEF energy on erythrocytes during AF ablation procedures are scarce. This study aimed to quantify the impact of PEF energy on erythrocyte damage during AF ablation by assessing specific hemolytic biomarkers. A total of 60 patients (age: 68 years, males: 72%, serum creatinine: 91 µmol/L) with AF underwent catheter ablation of AF using PEF energy delivered by a multipolar pentaspline Farawave catheter (Farapulse, Boston Scientific, Inc.). Ablation beyond pulmonary vein isolation was performed at the operator's discretion. Peripheral venous blood was sampled for assessing the plasma levels of free hemoglobin (fHb), direct (conjugated) bilirubin, lactate dehydrogenase (LDH), and creatinine before, immediately after the ablation, and on the next day. Following the PEF ablation with duration of [median (interquartile range)] 75 (58, 95) min, with 74 (52, 92) applications and PVI only in 27% of patients, fHb, LDH, and direct bilirubin significantly increased, from 40 (18, 65) to 493 (327, 848) mg/L, from 3.1 (2.6, 3.6) to 6.8 (5.0, 7.9) µkat/L, and from 12 (9, 17) to 28 (16, 44) µmol/L, respectively (all p < .0001). A strong linear correlation was found between the peak fHb and the number of PEF applications (R = 0.81, p < .001). The major hemolysis (defined as fHb >500 mg/L) was predicted by the number of PEF applications with the corresponding area under the receiver operating characteristic curve of 0.934. The optimum cut-off value of >74 PEF applications predicted the major hemolysis with 89% sensitivity and 87% specificity. Catheter ablation of AF using PEF energy delivered from a pentaspline catheter is associated with significant intravascular hemolysis. More than 74 PEF applications frequently resulted in major hemolysis. However, the critical amount of PEF energy that may cause kidney injury in susceptible patients remains to be investigated.

Outcomes of atrial fibrillation ablation in community hospitals with and without onsite cardiothoracic surgery availability.

Limited data exist on outcomes of atrial fibrillation (AF) catheter ablation based on hospital setting and, specifically, the availability of onsite cardiothoracic surgery (CTS). We aimed to describe the characteristics and outcomes of catheter ablation for AF performed at a facility with and without CTS. This was a retrospective study of consecutive patients who underwent catheter ablation for AF at hospital with (CTS) and without cardiothoracic surgery (N-CTS) from January 2011 through December 2019. Clinical and procedural characteristics, complications, and 1-year outcomes, including clinical events and AF recurrence, were collected. There were 326 unique patients who underwent an index AF ablation procedure: 206 CTS patients and 120 N-CTS patients. There were no differences inoverall cardiac complications (2.5% vs. 5.8%), including mapping catheter entrapment requiring open-heart surgery (0% vs. 0.5%), pericardial effusion requiring pericardiocentesis (0.8% vs. 0.5%), hemopericardium (1.7% vs. 0.5%), acute myocardial infarction (0% vs. 1.0%), and sinus node injury (0% versus 0.5%) (all P values > .05)between N-CTS and CTS patients. Likewise, overall noncardiac complications (20.7% vs. 19.8%, P = .85), including bleeding, cerebrovascular accident, and phrenic or vagus nerve injury, were similar between N-CTS and CTS hospitals. Also, 1-year cumulative Kaplan-Meier estimates of overall AF recurrence (11.6% vs. 16.4%; log-rank P = 0.21; HR 1.47; 95% CI, 0.79-2.74) were not statistically significant between N-CTS and CTS hospitals. Catheter ablation procedure is safe and effective regardless of onsite CTS presence, and there were no significant differences between the two hospital settings.

Preliminary Insights Into Early Ambulation and Hemostasis After Atrial Fibrillation Ablation Using the Perclose Vascular Closure Device.

The introduction of the Perclose vascular closure device (VCD) for atrial fibrillation (AF) ablation procedures in Japan is expected to facilitate early ambulation. The study population comprised 554 patients undergoing AF ablation, of whom 377 successfully underwent Perclose VCD deployment at the end of the procedure. At 4 h after the procedure, 94% (353/377 patients) achieved early hemostasis and 57% (213/377 patients) achieved early ambulation. Notably, 0.5% (2/377 patients) developed acute deep vein thrombosis. The Perclose VCD demonstrated promising efficacy in achieving early hemostasis, potentially facilitating early ambulation and discharge in appropriate patients.

Short- and long-term outcomes in isolated vs. hybrid thoracoscopic ablation in patients with atrial fibrillation: a systematic review and reconstructed individual patient data meta-analysis.

Both isolated thoracoscopic and hybrid thoracoscopic atrial fibrillation (AF) ablation techniques have demonstrated favourable outcomes in the management of patients with (long-standing) persistent AF, as compared with catheter ablation. However, it is currently unknown whether there is a difference in short- and long-term outcomes when comparing these two minimally invasive surgical AF ablation procedures. Therefore, a systematic review and meta-analysis were performed to investigate these two techniques, with a specific emphasis on long-term freedom from atrial tachyarrhythmias (ATAs). A systematic search through PubMed, EMBASE, and the Cochrane Library databases was performed. All studies reporting on short-term outcomes were included in the meta-analysis. A pooled analysis of long-term freedom from ATA was performed based on Kaplan-Meier (KM) curve-derived individual patient data. Reconstructed individual time-to-event data were analysed in a multivariable Cox frailty model with adjustments for age, sex, type of AF, duration of AF history, and study variable (frailty term in the frailty Cox model). In total, 53 studies were included in the meta-analysis, encompassing 4950 patients. There were no differences in major short-term outcomes (mortality or stroke) between isolated thoracoscopic and hybrid thoracoscopic ablation. A total of 18 studies reported KM curves for long-term freedom from ATA, comprising 2038 patients. Adjusted analysis revealed that hybrid ablation was significantly associated with greater freedom from ATA [adjusted hazard ratio (aHR) = 0.59, 95% confidence interval (CI): 0.43-0.83, P < 0.001] compared with isolated thoracoscopic ablation. Additionally, older age (aHR = 1.07, 95% CI: 1.03-1.12, P = 0.002) and a higher percentage of male patients (aHR = 1.02, 95% CI: 1.01-1.03, P < 0.001) were significantly associated with lower long-term freedom from ATA recurrence. Hybrid thoracoscopic AF ablation is associated with a greater long-term freedom from ATA when compared with isolated thoracoscopic ablation, without differences in complications.

The use of Intracardiac Echocardiography in Catheter Ablation of Atrial Fibrillation.

Intracardiac echocardiography (ICE) provides real-time, fluoroless imaging of cardiac structures, allowing optimal catheter positioning and energy delivery during ablation procedures. This review summarizes the use of ICE in catheter ablation of atrial fibrillation (AF). Growing evidence suggests that the use of ICE improves procedural safety and facilitates radiofrequency and cryoballoon AF ablation. ICE-guided catheter ablation is associated with reduced procedural duration and fluoroscopy use. Recent studies have examined the role of ICE in guiding novel ablation techniques, such as pulsed field ablation. Finally, the use of ICE allows for early detection and timely management of potentially serious procedural complications. Intracardiac echocardiography offers significant advantages during AF ablation procedures and its use should be encouraged to improve procedural safety and efficacy.

Spanish catheter ablation registry. 23rd official report of the Heart Rhythm Association of the Spanish Society of Cardiology (2023)

Introduction and objectivesWe report the results of the 2023 Spanish catheter ablation registry. MethodsProcedural data were collected and incorporated into the REDCap platform by all participating centers through a specific form. ResultsThere were 104 participating centers in 2023 compared with 103 in 2022. In 2023, the total number of ablation procedures was 26 207, indicating a stabilization of the increase observed in 2022 following the pandemic. The increase was mainly due to procedures for atrial fibrillation (AF), with a total of 9942 ablations, representing 38% of all substrates. Notably, pulse-field ablation represented 10.3% of all AF ablation procedures, leading single-shot ablation strategies to outnumber point-by-point AF ablation for the first time in the history of the registry. Cavotricuspid isthmus ablation remained the second most targeted substrate (19% of all substrates, n=5067). The overall acute success rate remained high (97%), with a downward trend in the complication rate (1.6% vs 1.8% in 2022) and mortality rate (0.03%; n=7). Compared with 2022, there was a significant increase in procedures performed using electro-anatomical mapping and zero-fluoroscopy techniques for cavotricuspid isthmus ablation (52% vs 26%), AV node re-entrant tachycardia (48% vs 34%), and accessory pathways (62% vs 22%). We registered 466 ablations in pediatric patients. ConclusionsThe data indicate a stabilization in the post-pandemic increase in ablation procedures, with an absolute and relative increase in AF as the predominant substrate. Success rates remained stable with a modest reduction in complication and mortality rates.

Acute procedural safety of the latest radiofrequency ablation catheters in atrial fibrillation ablation: Data from a large prospective ablation registry.

Safety data of the latest radiofrequency (RF) technologies during atrial fibrillation (AF) ablation in real-world clinical practice are limited. We sought to evaluate the acute procedural safety of the four latest ablation catheters commonly used for AF ablation. A total of 3957 AF ablation procedures performed between January 2022 and December 2023 at 20 centers with either the THERMOCOOL SMARTTOUCH SF (STSF), TactiCath (TC), QDOT Micro (QDM), or TactiFlex (TF) were retrospectively analyzed. In total, QDM, STSF, TF, and TC were used in 343 (8.7%), 1793 (45.3%), 1121 (28.4%), and 700(17.7%) procedures. Among 2406 index procedures, electrical pulmonary vein isolations were successfully achieved in 99.5%. Despite similar total procedure times in the four groups, the total fluoroscopic time was significantly shorter for QDM/STSF with CARTO than TF/TC with EnSite (18.7 ± 14 vs. 27.6 ± 20.6 min, p < .001) and longest in the TF group. The incidence of cardiac tamponade was 0.7% (0.5% and 0.9% during index and redo procedures, 0.8% and 0.3% for paroxysmal and non-paroxysmal AF) and was significantly lower for QDM/STSF than TF/TC (0.2% vs. 1.1%, p = .008) and highest in the TF group. The incidence of cardiac tamponade was higher for TF than TC and STSF than QDM. In the multivariate analysis, TF/TC with EnSite was a significant independent predictor of cardiac tamponade during both the index (odds ratio [OR] = 4.8, 95% confidence interval [CI] = 1.3-17.5, p = .02) and all procedures (OR = 3.0, 95% CI = 1.3-7.2, p = .01). The incidence of cardiac tamponade and the fluoroscopic time during AF ablation significantly differed among the latest RF catheters and mapping systems in real-world clinical practice.