Atrial Fibrillation Ablation Procedures Research Articles

Atrial Fibrillation Recurrence Rate in Different Clinical Groups: Coronary Artery Disease and Age Matter

BACKGROUND: Catheter ablation (CA) is an established method for atrial fibrillation (AF) treatment. Up to 20% of patients with AF develop coronary artery disease (CAD) as a secondary diagnosis. The data on whether the CAD affects the efficacy of AF ablation is contrary, while arterial hypertension is a known risk factor for AF as well as for AF recurrence after the CA.
 AIM: We conducted this research to assess the AF recurrence rate and its risk factors after the primary catheter AF ablation procedure in the different clinical groups including IdiopathicAF, AF concomitant to arterial hypertension (HTN) and AF concomitant to CAD.
 MATERIALS AND METHODS: Patients who underwent 451 PVI procedures performed since January 2016 to December 2017 were screened for AH, CAD and other structural heart disease. Among them 153 pts were selected for the subsequent analysis and divided into 3 groups IdiopathicAF, AF + AH, AF + CAD.
 RESULTS: The presence of CAD (r = 0.313, p 0.001), age (r = 0.224, p = 0.008), CHA2DS2-VASc score (r = 0.279, p = 0.001), history of MI (r = 0.240, p = 0.004), LA size (r = 0.204, p = 0.018) were correlated with the recurrence rate. In the AF + CAD group patients older than 65 years demonstrated dramatically lower AF-free survival rate (37.5%) in comparison to younger CAD population (75%, log-rank p 0.001) as well as to younger and older non-CAD patients.
 CONCLUSIONS: The presence of CAD should always attract the attention of physicians before considering the AF ablation as an option to treatment. Elderly CAD patients have the lowest ablation efficacy and the best strategy for this group (more extensive primary ablation or conversion to the permanent AF) needs to be studied.

PO-01-027 A MULTIPOLAR ELECTRODE MAPPING CATHETER AND A MECHANICAL VALVE: TO USE OR NOT TO USE?

n/a n/a n/a A 65 year old woman with a history of a mechanical mitral valve (MMV), hypertrophic cardiomyopathy, and multiple ablation procedures for atrial fibrillation and atrial flutter presented to the electrophysiology lab for another attempt to treat her atrial arrhythmias. During left atrial (LA) mapping, a portion of the OctaRay™ catheter became entrapped in the MMV. With gentle traction and clockwise torque, the catheter was freed from this without requiring unusual force; however, on one of the splines of the catheter, recordings were lost; the catheter was removed from the long introducer sheath in the LA and inspected, showing that the distal-most 3 of 6 microelectrodes on one spline were missing (Fig 1A). The patient remained stable throughout this process. Fluoroscopy of the MMV showed no evidence of the retained electrodes; likewise, cinefluoroscopy of the head showed no evidence of electrodes in this region. After ensuring that the patient was hemodynamically stable and there were no ECG changes, the procedure was continued without event. Three reentrant atypical left atrial flutters were mapped and eliminated with radiofrequency energy and were non-inducible at the end of the ablation protocol. At the conclusion of the procedure, fluoroscopy was performed of the entire body, showing that the severed electrodes had more than likely lodged in an artery branch in the right gluteal region (Fig 1B). Colleagues from interventional radiology determined that an angiogram was not necessary and that the retained electrodes were in an artery branch that posed her no harm and consequently were not worth attempting to retrieve. She continued to do well post-procedure and was discharged home the following day without symptoms. In LA macroreentry, important electrophysiologic information may reside in areas adjacent to MMV attachments, mapping of which may provide critical data. Our group has performed >20 LA ablation procedures using PentaRay™ catheters on patients with MMVs without valve entrapment or catheter damage; PentaRay™ splines appear to be more robust than the more delicate OctaRay™ splines. Thus, it may be wise to avoid using OctaRay™ catheters in cases of MMV, or great care should be taken to prevent splines from contacting the MMV.

AB-453070-4 INCREMENTAL EFFICACY FOR REPEAT ABLATION PROCEDURES FOR CATHETER ABLATION OF ATRIAL FIBRILLATION: 5-YEAR FOLLOW-UP

Catheter ablation has emerged as an effective strategy for the treatment of Atrial fibrillation (AF) but 20-40% of patients will require a repeat ablation. While one repeat ablation is considered clinically useful, the role of more than one repeat is not well known over long-term follow-up. Excessive repeat ablation can limit access to patients who need their first ablation. We aimed to describe the outcome of one or more repeat AF ablations in a large cohort of paroxysmal and persistent AF patients. We retrospectively included patients who underwent their first, second, third and fourth AF ablation at our center between 2005 and 2019. Wide-antral pulmonary vein isolation (PVI) was performed in all patients. Posterior wall isolation was left to the discretion of the operator but was used in almost all persistent patients. Patient demographics, medical history, procedural details, and complications were collected in a database. Patients were monitored with a 24-to-48-hour Holter every three months for the first year after each ablation with follow-ups every 6-12 months thereafter. Freedom from atrial arrhythmia was evaluated after each AF ablation. We included 2895 patients that underwent catheter ablation for AF at our institution. From them, 1809 (62.5%) had paroxysmal AF, 950 (32.8%) had persistent AF and 136 (4.7%) long persistent AF. Age was 61 ± 10 years, left atrial diameter was 42 ± 6 mm, and radiofrequency was used for 97% of procedures. After one ablation, freedom from atrial arrhythmias was 52%. Among those 1052 patients that had a recurrence, 576 (55%) underwent a second AF ablation procedure, 103 (10%) underwent a third procedure and 20 (2%) underwent a fourth. Success rates for the second, third and fourth ablation were 57%, 60% and 40% respectively. The success rates for repeat procedures for paroxysmal and persistent patients separately are provided in the Table. After the second ablation, freedom from atrial arrhythmia in our entire cohort significantly improved from 52% to 67% (p<0.001). However, incremental benefit did not change much after the third (68%; p=0.35) and fourth ablation (69%; p=0.8) (Figure). The success rate of repeat ablations drops off after a third procedure, regardless of AF type. In the entire cohort, the population success rate changes significantly from the first to second procedure, but not appreciably so for more than 2 procedures.Tabled 1Second Ablation Success (%)Third Ablation Success (%)Fourth Ablation Success (%)Paroxysmal AF56.5%60.4%41.7%Persistent and Long-standing persistent AF56.9%59.3%37.5% Open table in a new tab

A U.K. Multicenter Retrospective Study of the Learning Curve and Relative Impact on Success Rates and Procedural Metrics of the RHYTHMIA HDx™ Mapping System.

The learning curve for the novel RHYTHMIA HDx™ 3-dimensional electroanatomic system is unknown. Retrospective data collection was carried out at 3 U.K. centers from the introduction of RHYTHMIA HDx™ (Boston Scientific, Marlborough, MA, USA) and associated mapping and ablation catheters. Patients were matched with controls using the CARTO® 3 mapping system (Biosense Webster Inc., Diamond Bar, CA, USA). Fluoroscopy, radiofrequency ablation, and procedure times; acute and long-term success; and complications were assessed. A total of 253 study patients along with 253 controls were included. Significant correlations existed between procedural efficiency metrics and center experience for de novo atrial fibrillation (AF) ablation (procedure time, Spearman's ρ = -0.624; ablation time, ρ = -0.795; both P < .0005) and de novo atrial flutter (AFL) ablation (ablation time, ρ = -0.566; fluoroscopy time, ρ = -0.520; both P = .001). No correlations existed for other assessed atrial arrhythmias. For de novo AF and AFL, metrics significantly improved after 10 procedures in each center (procedure time [AF only, P = .001], ablation time [AF, P < .0005; AFL, P < .0005], and fluoroscopy time [AFL only, P = .0022]) and became comparable to those of controls. Acute success and long-term success did not experience significant improvements with experience, but they were comparable to the control group throughout. Complications with RHYTHMIA HDx™ were comparable to those associated with CARTO® 3. In conclusion, a short learning curve exists with the use of RHYTHMIA HDx™ for standardized procedures (de novo AF/AFL). Procedural performance improved and became comparable to that seen with CARTO® 3 following 10 cases at each center. Clinical outcomes at 6 and 12 months and complications were no different from those observed in controls.

AB-452642-1 TEMPORAL TREND IN PROCEDURE-RELATED COMPLICATIONS OF CATHETER ABLATION FOR ATRIAL FIBRILLATION: A SYSTEMATIC REVIEW AND POOLED ANALYSIS OF RANDOMIZED CONTROL TRIALS.

Catheter ablation of atrial fibrillation (AF) is one of the most commonly performed procedures in electrophysiology. However, it is associated with potentially significant complications. Reported procedure-related complication rates are highly variable, depending in part on study design. Objectives of this systematic review and pooled analysis were to determine the rate of procedure-related complications associated with catheter ablation of AF using data from randomized control trials (RCTs), and to assess temporal trends. MEDLINE and EMBASE databases were searched from January 2013 to September 2022 for RCTs that included patients undergoing a first catheter ablation procedure for the treatment of AF using either radiofrequency or cryoballoon ablation (PROSPERO CRD42022370273). The study adhered to Cochrane Collaboration guidelines. The quality of included trials was assessed using the Cochrane Collaboration’s tool for assessing risk of bias in RCTs. Results were reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses report. A total of 1,468 references were retrieved and evaluated, of which 89 studies met inclusion criteria. A total of 15,701 patients who underwent a first catheter ablation procedure for AF were included in the current analysis. Procedure-related and severe complication rates were 3.5% (95%CI: 2.9-4.1) and 2.1% (95%CI: 1.7-2.5), respectively. Vascular complications were the most frequent type of complication (1.21%). The most frequently reported complications were then pericardial effusions and tamponades (0.51%), strokes/transient ischemic attacks (0.48%) and reversible phrenic nerve palsy (0.40%). The procedure-related complication rate during the most recent 5-year period of publication [2018-2022] was significantly lower than during the earlier 5-year period [2013-2017] (2.9% vs 4.1%, p=0.043). The pooled mortality rate was stable over the two time periods (0.06% vs 0.05%, p=0.562). By meta-regression analyses, there was no significant difference in complication rate according to pattern of AF (paroxysmal or non-paroxysmal), ablation modality (radiofrequency or cryoballoon), or additional ablation strategies beyond pulmonary vein isolation. Procedure-related complications and mortality rates associated with catheter ablation of AF are low and have declined in the past decade.

PO-01-042 OUTCOMES IN ATRIAL FIBRILLATION USING ADENOSINE TO CHECK FOR DORMANT CONNECTIONS DURING CATHETER ABLATION

Adenosine is used to uncover dormant connections after pulmonary vein isolation (PVI) for atrial fibrillation (AF). There are conflicting reports in the literature on whether this technique reduces AF recurrence. To determine if adenosine provocation (APROV) to check for dormant conduction following PVI reduces AF recurrence. AF ablation procedures performed at a single center from 2013 to 2021 were analyzed. The endpoint was AF recurrence after a 3-month blanking period. AF recurrence was defined as AF lasting for more than 30 seconds. 1:1 propensity score match (PSM) was performed with covariates that have been shown to predict AF recurrence in previous studies (gender, age, BMI, AF classification, obstructive sleep apnea (OSA), hypertension (HTN), and diabetes mellitus (DM). The minimum duration of follow-up was 6 months. Adenosine was used at the procedure physician’s discretion with a minimum dose of 12 mg. Dormant connections were ablated, and persistent PVI with elimination of dormant conduction with adenosine re-challenge was confirmed in all cases. Kaplan-Meier analysis was conducted to assess time to AF recurrence in the entire cohort and the PSM cohort. We analyzed 1544 AF ablations (1111 de novo, 428 repeat ablation) at a single academic medical center. Adenosine was used in 64% of cases. The study population was 65.5% male with a mean age 66 years. Patient co-morbidities included DM (17%), HTN (55%), and OSA (18%). There was no significant difference in time to AF recurrence in the entire cohort with APROV (HR 0.95, CI 0.78-1.16, p=0.6). After PSM, there were 450 patients in each group with AF ablations with 72% paroxysmal AF and 28% persistent AF. There was no difference in time to AF recurrence in the PSM cohort with APROV (HR 0.94, CI 0.75-1.18, p=0.6, Figure 1), with no differences observed between de novo vs repeat ablations. Adenosine provocation is not associated with decreased AF recurrence.

PO-02-167 IMPACT OF OBESITY ON QUALITY OF LIFE AND CLINICAL OUTCOME IN PATIENTS WITH ATRIAL FIBRILLATION UNDERGOING PRIMO PULMONARY VEIN ISOLATION

Obesity is a major risk factor for the incidence and progression of atrial fibrillation (AF), negatively impacting AF ablation outcomes. Weight loss in obese patients prior to AF ablation may improve quality of life (QoL) and AF ablation success rates. To assess the impact of overweight and obesity on patient-reported outcomes (QoL scores) and clinical outcomes (AF recurrence) in patients undergoing index AF ablation procedure. This single-center cohort study retrospectively included 238 patients undergoing primo radiofrequency (RF) pulmonary vein isolation (PVI) who completed 1 year follow-up, including the Toronto AF Severity Scale (AFSS) questionnaire at baseline, 4-, and 12 months post-PVI for assessment of QoL (AF severity, AF burden, and global well-being). At baseline, patients were categorized by body mass index (BMI): normal (<25 kg/m2); overweight (≥25 - <30 kg/m2); and obese (≥30 kg/m2). AF recurrence was evaluated by either 24-h Holter monitoring, AliveCor KardiaMobile devices, or conventional electrocardiograms (ECG). Patients were divided based on BMI: 37.8% normal; 44.1% overweight; and 18.1% obese. Obese patients were more likely to be women (men 46.5%,p<0.01), and have diabetes mellitus (25.6%,p<0.01). AF recurrence rates detected during 12 months follow-up were similar among the three BMI groups: normal 27.8%, overweight 33.3%, and obese 30.2% (p=0.70). After AF ablation, all QoL scores in each BMI group improved, with no between-group differences (Table 1). Subgroup analysis showed significantly improved QoL scores in patients without AF recurrence independent of BMI category, however in patients with AF recurrence no significant improvement of AF severity and global well-being was found (Fig 1). Despite AF recurrence, self-reported AF burden significantly improved in the normal and overweight categories, but not in obese patients. A high BMI was not a major determinant of AF recurrence rates after a primo PVI. QoL after PVI was found to be determined by AF recurrence rather than BMI. This study suggests that obese patients might benefit from PVI to a similar extent compared to non-obese patients, though self-reported AF burden might differ between groups.

AB-452642-2 COMPLICATIONS ASSOCIATED WITH CATHETER ABLATION OF ATRIAL FIBRILLATION IN CURRENT PRACTICE: INSIGHTS FROM A LARGE, REAL-WORLD COLLABORATION

Catheter ablation is a cornerstone treatment for symptomatic atrial fibrillation (AF) with major improvements in safety over time. However, rates of adverse events with use of current techniques in a contemporary quality-focused network remain undefined. Across a large, real-world sample, we sought to describe (1) rates of major, adverse events associated with catheter ablation of AF and (2) patient-level factors associated with complications. Utilizing the REAL-AF collaboration, a registry of contemporary AF ablation procedures with granular patient, procedural and follow-up data comprised of cases from over 50 operators across academic and non-academic sites, we evaluated all patients undergoing their first ablation procedure from January 2018 – June 2022. Risk-adjusted analyses were conducted to evaluate the relationship between patient factors and complications. Among 3144 patients (age 66.1 +/- 11.0 years, 42% female, 67.1% paroxysmal, 32.9% persistent) who underwent AF ablation, procedure-related complications (n =77) were identified in 65 patients (2.1%) with multiple complications occurring in 9 patients (0.2%). Most complications (n=70, 93.5%) occurred in the peri-procedural (within 30 days) period and 6.5% (n=5) after 30 days, the latter of which all represented vascular injuries (Figure). Major complications (18 of 72 peri-procedural complications, 25.0%) are defined, detailed, and associated data reported in the Figure. Unadjusted (16.0% without CHF vs. 33.3% with CHF, p = 0.045) and risk-adjusted (OR 2.8, 95% CI 1.03-7.60, p=0.045) analyses indicated history of CHF was associated with a composite outcome of major complications. Analyses of independent complications showed those who suffered from peri-procedural stroke (n=3) were of significantly greater age (77.3 +/- 5.5 years vs. 66.1 +/- 10.9 years, p=0.035). Risk-adjusted analyses showed history of vascular disease (OR 2.9, 95% CI 1.02-8.20, p=0.045) was associated with vascular injury (n=18). From 0-695 days post-procedure, 31 deaths occurred (unknown cause: 17, COVID-19 related: 4, heart failure: 2, cardiac arrest: 2). Major complications represent rare events among those undergoing AF ablation in current practice. Risk-adjusted analyses suggest a history of CHF is associated with major complications. Similarly, older age and a history of vascular disease are associated with stroke and vascular complications, respectively.

PO-02-204 COLCHICINE USAGE FOR PREVENTION OF POST ATRIAL FIBRILLATION ABLATION PERICARDITIS IN PATIENTS UNDERGOING HIGH POWER SHORT DURATION ABLATION

Radiofrequency ablation (RFA) for atrial fibrillation (AF) can be associated with up to 10% incidence of post-operative pericarditis, suspected to be more prevalent with the advent of high-power short duration (HPSD) ablation. This has led to widespread use of colchicine, an anti-inflammatory medication, for prevention of post-AF ablation pericarditis. However, the utility of preventative colchicine remains unproven. To evaluate the efficacy of a routine post-operative colchicine regimen for prevention of post-ablation pericarditis in patients (pts) undergoing HPSD ablation for AF. We retrospectively evaluated consecutive single-operator HPSD AF ablation procedures at our institution from June 2019 to July 2022. A colchicine protocol was introduced in June 2021 for prevention of post-ablation pericarditis. None of the pts before this date received preventative colchicine while all consecutive pts after this date received routine colchicine 0.6 mg twice daily for 14 days starting on the procedure day. Pts were divided into colchicine and non-colchicine groups (gps). We recorded the incidence of post ablation chest pain, emergency room (ER) visit for chest pain, pericardial effusion, pericardiocentesis, any ER visit, hospitalization, AF recurrence and cardioversion (CV) for AF within the first 30 days post-ablation. We also recorded colchicine-related side effects and medication compliance. Out of 225 consecutive procedures, 20 were excluded for lack of follow-up data, yielding 101 pts in the colchicine gp and 104 pts in the non-colchicine gp. Both gps were well-matched for demographic and procedural parameters (Table 1). There was no significant difference in post-ablation chest pain (9.9% vs 8.6%, p = 0.7), pericardial effusion (2.9% vs 0.9%, p = 0.1), ER visits (11.9% vs 12.5%, p = 0.2), 30-day hospitalization for AF recurrence (0.9% vs 0.96%,p = 0.3) and 30-day need for CV for AF (3.9 % vs 5.7%, p = 0.2) (Table 1). 15 pts had severe colchicine-related diarrhea, out of which 12 discontinued it prematurely (Figure 1). In this single-operator retrospective analysis, preventative colchicine was not associated with any significant reduction in the incidence of pericarditis, pericardial effusion, ER visits or AF recurrence within the first 30 days after HPSD ablation for AF. Colchicine usage was associated with significant diarrhea affecting patient compliance. Our findings argue against routine use of colchicine for prevention of post AF-ablation pericarditis.

Impact of Colchicine Monotherapy on the Risk of Acute Pericarditis Following Atrial Fibrillation Ablation

BackgroundAcute pericarditis is a known complication of ablation procedures for atrial fibrillation (AF). ObjectivesThis study aimed to evaluate the benefits of colchicine monotherapy in terms of reducing the risk of pericarditis and related hospitalization rate in AF patients undergoing catheter ablation. MethodsConsecutive AF patients undergoing first catheter ablation were classified into 3 groups based on their colchicine use: Group 1: no colchicine; group 2: colchicine from 7 days before to 1 month after ablation; and group 3: colchicine from the day of the procedure to 1 month after. Standard institutional protocol was used to follow all patients for 1 year. ResultsA total of 1,075 patients were classified into groups 1 (n = 607), 2 (n = 213), and 3 (n = 255). Symptoms of acute pericarditis were reported in 129 patients (12%): group 1: n = 106 (17.5%); group 2: n = 4 (1.9%); and group 3: n = 19 (7.5%); P < 0.001. Rate of mild-moderate as well as severe pericarditis were significantly lower in group 2. In the multivariable regression analysis, pre- and post-ablation colchicine use was seen to be associated with significantly lower risk of acute pericarditis and related hospitalization compared with the other 2 groups. In addition, at 1-year follow-up, arrhythmia-free survival rate was significantly higher in paroxysmal AF patients receiving colchicine compared with the no-colchicine population. ConclusionsColchicine therapy starting 7 days before to 1 month after the ablation procedure was associated with significantly lower risk of acute pericarditis and related hospitalization. In addition, paroxysmal AF patients receiving colchicine had a higher arrhythmia-free survival rate compared with those not receiving colchicine.

A Focal Ablation Catheter Toggling Between Radiofrequency and Pulsed Field Energy to Treat Atrial Fibrillation

BackgroundBecause of its safety, “single-shot” pulsed field ablation (PFA) catheters have been developed for pulmonary vein isolation (PVI). However, most atrial fibrillation (AF) ablation procedures are performed with focal catheters to permit flexibility of lesion sets beyond PVI. ObjectivesThis study sought to determine the safety and efficacy of a focal ablation catheter able to toggle between radiofrequency ablation (RFA) or PFA to treat paroxysmal or persistent AF. MethodsIn a first-in-human study, a focal 9-mm lattice tip catheter was used for PFA posteriorly and either irrigated RFA (RF/PF) or PFA (PF/PF) anteriorly. Protocol-driven remapping was at ∼3 months postablation. The remapping data prompted PFA waveform evolution: PULSE1 (n = 76), PULSE2 (n = 47), and the optimized PULSE3 (n = 55). ResultsThe study included 178 patients (paroxysmal/persistent AF = 70/108). Linear lesions, either PFA or RFA, included 78 mitral, 121 cavotricuspid isthmus, and 130 left atrial roof lines. All lesion sets (100%) were acutely successful. Invasive remapping of 122 patients revealed improvement of PVI durability with waveform evolution: PULSE1: 51%; PULSE2: 87%; and PULSE3: 97%. After 348 ± 652 days of follow-up, the 1-year Kaplan-Meier estimates for freedom from atrial arrhythmias were 78.3% ± 5.0% and 77.9% ± 4.1% for paroxysmal and persistent AF, respectively, and 84.8% ± 4.9% for the subset of persistent AF patients receiving the PULSE3 waveform. There was 1 primary adverse event—inflammatory pericardial effusion not requiring intervention. ConclusionsAF ablation with a focal RF/PF catheter allows efficient procedures, chronic lesion durability, and good freedom from atrial arrhythmias—for both paroxysmal and persistent AF. (Safety and Performance Assessment of the Sphere-9 Catheter and the Affera Mapping and RF/PF Ablation System to Treat Atrial Fibrillation; NCT04141007 and NCT04194307)

Major drivers of healthcare system costs and cost variability for routine atrial fibrillation ablation.

Catheter ablation is an effective treatment for atrial fibrillation (AF) but incurs significant financial costs to payers. Reducing variability may improve cost effectiveness. We aimed to measure (1) the components of direct and indirect costs for routine AF ablation procedures, (2) the variability of those costs, and (3) the main factors driving ablation cost variability. Using data from the University of Utah Health Value Driven Outcomes system, we were able to measure direct, inflation-adjusted costs of uncomplicated, routine AF ablation to the healthcare system. Direct costs were considered costs incurred by pharmacy, disposable supplies, patient labs, implants, and other services categories (primarily anesthesia support) and indirect costs were considered within imaging, facility, and electrophysiology lab management categories. A total of 910 patients with 1060 outpatient ablation encounters were included from January 1, 2013, to December 31, 2020. Disposable supplies accounted for the largest component of cost with 44.8 ± 9.7%, followed by other services (primarily anesthesia support) with 30.4 ± 7.7% and facility costs with 16.1 ± 5.6%; pharmacy, imaging, and implant costs each contributed <5%. Direct costs were larger than indirect costs (82.4 ± 5.6% vs 17.6 ± 5.6%). Multivariable regression showed that procedure operator was the primary factor associated with AF ablation overall cost (up to 12% differences depending on operator). Direct costs and other services (primarily anesthesia) drive the majority costs associated with AF ablations. There is significant variability in costs for these routine, uncomplicated AF ablation procedures. The procedure operator, and not patient characteristic, is the main driver for cost variability.

Ultrasound guidance for femoral venous access in patients undergoing pulmonary vein isolation: A quasi-randomized study.

Routine ultrasound (US) guidance for femoral venous access to decrease vascular complications of atrial fibrillation (AF) ablation procedures has been advocated. However, the benefit has not been unequivocally demonstrated by randomized-trial data. Consecutive patients undergoing pulmonary vein isolation (PVI) on uninterrupted anticoagulant treatment were included. A quasi-random allocation to either US-guided or conventional puncture group was based on which of the two procedure rooms the patient was scheduled in, with only one of the rooms equipped with a US machine including a vascular transducer. The same four novice operators in rotation, with no relevant previous experience in US-guided vascular access performed venous punctures in both rooms. Major and minor vascular complications and the rate of prolonged hospitalization were compared. Major vascular complication was defined as groin hematoma, arteriovenous fistula, or pseudoaneurysm. Hematoma was considered as a major vascular complication if it met type 2 or higher Bleeding Academic Research Consortium criteria (requiring nonsurgical, medical intervention by a health care professional; leading to hospitalization or increased level of care, or prompting evacuation). Of the 457 patients 199 were allocated to the US-guided puncture group, while the conventional, palpation-based approach was performed in 258 cases. Compared with the conventional technique, USguidance reduced the rate of any vascular complication (11.63% vs. 2.01%, p < .0001), including both major (4.26% vs. 1.01%, p = .038) and minor (7.36% vs. 1.01%, p = .001) vascular complications. In addition, the rate of prolonged hospitalization was lower in the US-guided puncture group (5.04% vs. 1.01%, p = .032). The use of US for femoral vein puncture in patients undergoing PVI decreased the rate of both major and minor vascular complications. This quasi-randomized comparison strongly supports adapting routine use of US for AF ablation procedures.

Study of Modifications Induced by Continued Direct Oral Anticoagulant Therapy during Atrial Fibrillation Ablation Procedures on Standard Hemostasis Parameters

Unfractionated heparin (UFH) is used as an anticoagulant during the atrial fibrillation (AF) ablation procedure to prevent the occurrence of thromboembolic events. Guidelines recommend an activated clotting time (ACT) greater than 300 s (s) based on studies of patients treated with vitamin K antagonist (VKA) for their AF. However, direct oral anticoagulants (DOACs) have supplanted VKAs in AF and are now used as first-line therapy. It is recommended not to interrupt them during the procedure, which could interfere with the ACT measures. To assess the real-life relationship between ACT, DOAC concentrations, and UFH anti-Xa activity in patients treated by uninterrupted DOAC therapy. We conducted a single-center retrospective study. We analyzed consecutive patients with AF who underwent catheter ablation under DOAC therapy. In total, 40 patients were included, including 15 (37.5%), 20 (50.0%), and 5 (12.5%) on rivaroxaban, apixaban, and dabigatran, respectively. Baseline ACT was significantly lower in the apixaban group. ACT was linearly correlated with the residual concentration of apixaban and dabigatran but not with rivaroxaban. After UFH injection, ACT was linearly correlated with the anti-Xa activity, regardless of DOAC. Patients in the apixaban group received a higher total dose of UFH during the procedure to achieve a target ACT > 300 s, which resulted in significantly higher anti-Xa activity during the procedure. Our results raise the question of optimal management of intra-procedural heparin therapy and highlight the limitations of the ACT test, particularly in patients on apixaban.

Initial Findings From the National Cardiovascular Data Registry of Atrial Fibrillation Ablation Procedures

BackgroundThe National Cardiovascular Data Registry (NCDR) AFib Ablation Registry was created to assess real-world prevalence, demographic characteristics, procedural management, and outcomes of patients undergoing atrial fibrillation (AF) ablation procedures. ObjectivesThe goal of this study was to characterize the patient, hospital, and physician characteristics and in-hospital outcomes related to AF ablation in the first 5 years of the registry. MethodsThis paper describes the AFib Ablation Registry structure and governance, outcome assessment processes, data quality, and data collection processes. The characteristics of the patient population, hospitals, and in-hospital outcomes are also described. ResultsA total of 76,219 patients were included in the registry between January 2016 and December 2020 (mean age 65.5 ± 10.3 years, 65.2% male, 55.8% paroxysmal AF, mean CHA2DS2-VASc score 2.7 ± 1.6) treated by 708 physicians in 162 hospitals. Successful isolation of all pulmonary veins was achieved in 92.4% of patients. The prevalence of any complication during procedural admission was 2.50% and major complication was 0.9%, including significant bradycardia in 0.47%, heart failure in 0.47%, and pericardial effusion requiring intervention in 0.44%. Hospitalization >1 day occurred in 11.8% of patients, and in-hospital death was rare (n = 41 [0.05%]). ConclusionsThe NCDR AFib Ablation Registry is the largest multicenter, prospective cohort study of patients undergoing catheter ablation worldwide. Results in the first 5 years showed that successful pulmonary vein isolation is achieved in the majority of patients, with a low rate of complications. Future studies from the registry will assess practice trends, evaluate treatment patterns associated with different patient outcomes, and support development of evidence-based guidelines.

First clinical experience using the DiamondTemp catheter and a novel omnipolar high-resolution mapping system for atrial fibrillation ablation.

The DiamondTemp (DT) radiofrequency ablation (RFA) catheter has been introduced as a new tool for atrial fibrillation (AF) ablation. The new technology allows for temperature-controlled irrigated ablation and real-time lesion assessment. Recently, the EnSite X mapping system became commercially available allowing for omnipolar and ultra-high-resolution mapping. We aimed to assess the feasibility of the new DT RFA catheter in performing AF ablation procedures in conjunction with the novel EnSite X system under routine clinical conditions. We analyzed data from 10 consecutive patients who underwent AF ablation using the DT RFA catheter guided by EnSite X. Procedural data and short-term follow-up were assessed as well as potential technical issues. Nine out of 10 patients underwent de-novo pulmonary vein isolation (PVI), and 1 patient underwent repeat ablation. First-pass isolation was observed in 7/10 patients. Total procedure duration (skin-to-skin) was 88.9 ± 30.1 min, and left atrium dwell time was 70 ± 22.3 min. The mean number of RF applications needed for PVI and additional ablation was 70.52 ± 26.70. The HD Grid SE mapping catheter was utilized in 8 patients and the Advisor SE in 2 patients. Bidirectional block of the applied lines was achieved in all patients. No steam pops were observed, and no intraprocedural complications occurred. This first clinical series demonstrated that temperature-controlled irrigated ablation in combination with the novel omnipolar and high-resolution mapping system resulted in rapid, efficient, and durable lesion formation under routine clinical conditions. Randomized controlled trials are needed to elucidate the impact on lesion formation, long-term outcomes, and reproducibility of our initial findings.

Left atrial reservoir strain measurements derived from intracardiac echocardiography in patients with atrial fibrillation: comparison with transthoracic echocardiography

BackgroundIntracardiac echocardiography (ICE) provides accurate left atrial (LA) anatomical information in the procedure of atrial fibrillation (AF) ablation but lacks LA functional assessment. LA reservoir strain (LASr) is an excellent marker of LA reservoir function. This study aimed to assess the agreement between LASr derived from ICE and transthoracic echocardiography (TTE) in AF patients and analyze the reproducibility of LASr assessed by ICE combined with speckle tracking imaging.MethodsThis study prospectively enrolled 110 patients with a clinical diagnosis of AF who were ready for AF ablation, including 71 patients with paroxysmal AF and 39 with persistent AF. TTE and ICE examinations were performed on each individual before AF ablation. LASr measurements derived from ICE and TTE images were using dedicated LA-tracking software. Pearson correlation coefficients (r) and Bland–Altman plots were used to evaluate the agreement of LASr between the two modalities. Intraclass correlation coefficients (ICCs) were used to assess intra- and inter-observer reproducibility.ResultsThe agreement between LASr obtained from ICE and TTE, especially between LASrLPV (LASr derived from LA left pulmonary vein view of ICE) and LASrTTE (LASr derived from TTE) were good in both paroxysmal and persistent AF patients [r = 0.890 (P < 0.001) for overall population; r = 0.815 (P < 0.001) and Bias ± LOA: -0.3 ± 9.9% for paroxysmal AF; r = 0.775 (P < 0.001) and Bias ± LOA: -2.6 ± 3.9% for persistent AF, respectively]. But the values of LASr derived from ICE were slightly lower than those of TTE, especially in patients with persistent AF. The ICCs for LASr derived from ICE were excellent (all ICCs > 0.90).ConclusionsIn patients with AF, LASr derived from ICE demonstrated excellent reproducibility and showed good agreement with LASr obtained from TTE. Obtaining LASr from ICE images may be a supplementary method to evaluate LA reservoir function in AF patients and expands the potential of ICE in the field of cardiac function assessment.Graphical

Sex differences in atrial fibrillation ablation in-hospital outcomes from the National Inpatient Sample database 2016-2019.

Research has shown mixed results when comparing in-hospital complications following atrial fibrillation ablation in women compared to men. To better quantify sex differences and in-hospital outcomes in atrial fibrillation ablation procedures and identify factors associated with poorer outcomes. We queried the NIS database from 2016 to 2019 for hospitalizations with a primary diagnosis of atrial fibrillation ablation and excluded patients with any other arrhythmias, ICD/pacemaker placement. We assessed demographics, in-hospital mortality, and complications of women compared to men. Admissions for atrial fibrillation were more common in females than males (849 050 vs. 815 665; p < .001). However, females were less likely to receive ablation (1.65% vs. 2.71%, OR: 0.60; 95% confidence interval: 0.57-0.64, p < .001), which persisted after adjusting for cardiomyopathy (adjusted OR: 0.61; 95% confidence interval: 0.58-0.65, p < .001). The primary outcome of in-hospital mortality was not statistically different in univariate analysis (0.39% vs. 0.36%, OR: 1.09, 95% CI: 0.44-2.72, p=.84), finding that did not change when adjusted for comorbidities (adjusted OR: 0.94, 95% CI: 0.36-2.49). The complication rate in hospitalized patients following ablation was 8.08%. The total unadjusted complication rate was higher for females than males (9.58% vs. 7.09%, p=.001); however, it was not significant when adjusted for risks (adjusted OR: 1.23, 95% CI: 0.99-1.53, p=.06). Female sex is not associated with increased complications or death in a real-world study of catheter ablation when results are adjusted for risks. However, females admitted with atrial fibrillation receive ablation less often than males during hospital admission.

Temporal trends in atrial fibrillation ablation procedures at an academic medical center: 2011-2021.

Radiofrequency ablation technology for treating atrial fibrillation (AF) has evolved rapidly over the past decade. We investigated the impact of technological and procedural advances on procedure times and ablation outcomes at a major academic medical center over a 10-year period. Clinical data was collected from patients who presented to NYU Langone Health between 2011 and 2021 for a first-time AF ablation. Time to redo AF ablation or direct current cardioversion (DCCV) for recurrent AF during a 3-year follow-up period was determined and correlated with ablation technology and practices, antiarrhythmic medications, and patient comorbid conditions. From 2011 to 2021, the cardiac electrophysiology lab adopted irrigated-contact force ablation catheters, high-power short duration ablation lesions, steady-pacing, jet ventilation, and eliminated stepwise linear ablation for AF ablation. During this time the number of first time AF ablations increased from 403 to 1074, the percentage of patients requiring repeat AF-related intervention within 3-years of the index procedure dropped from 22% to 14%, mean procedure time decreased from 271 ± 65 to 135 ± 36 min, and mean annual major adverse event rate remained constant at 1.1 ± 0.5%. Patient comorbid conditions increased during this time period and antiarrhythmic use was unchanged. Rates of redo-AF ablation or DCCV following an initial AF ablation at a single center decreased 36% over a 10-year period. Procedural and technological changes likely contributed to this improvement, despite increased AF related comorbidities.

Manifold analysis of the P-wave changes induced by pulmonary vein isolation during cryoballoon procedure

Background/Aim:In atrial fibrillation (AF) ablation procedures, it is desirable to know whether a proper disconnection of the pulmonary veins (PVs) was achieved. We hypothesize that information about their isolation could be provided by analyzing changes in P-wave after ablation. Thus, we present a method to detect PV disconnection using P-wave signal analysis. Methods:Conventional P-wave feature extraction was compared to an automatic feature extraction procedure based on creating low-dimensional latent spaces for cardiac signals with the Uniform Manifold Approximation and Projection (UMAP) method. A database of patients (19 controls and 16 AF individuals who underwent a PV ablation procedure) was collected. Standard 12-lead ECG was recorded, and P-waves were segmented and averaged to extract conventional features (duration, amplitude, and area) and their manifold representations provided by UMAP on a 3-dimensional latent space. A virtual patient was used to validate these results further and study the spatial distribution of the extracted characteristics over the whole torso surface. Results:Both methods showed differences between P-wave before and after ablation. Conventional methods were more prone to noise, P-wave delineation errors, and inter-patient variability. P-wave differences were observed in the standard leads recordings. However, higher differences appeared in the torso region over the precordial leads. Recordings near the left scapula also yielded noticeable differences. Conclusions:P-wave analysis based on UMAP parameters detects PV disconnection after ablation in AF patients and is more robust than heuristic parameterization. Moreover, additional leads different from the standard 12-lead ECG should be used to detect PV isolation and possible future reconnections better.