Consecutive Paroxysmal Atrial Fibrillation Patients Research Articles

Distance-dependent neuromodulation effect during thermal ablation for atrial fibrillation.

Thermal atrial fibrillation (AF) ablation exerts an additive treatment effect on the cardiac autonomic nervous system (CANS). This effect is mainly reported during ablation of the right superior pulmonary vein (RSPV), modulating the right anterior ganglionated plexus (RAGP), which contains parasympathetic innervation to the sinoatrial node in the epicardial fat pad between RSPV and superior vena cava (SVC). However, a variable response to neuromodulation after ablation is observed, with little to no effect in some patients. Our objective was to assess clinical and anatomic predictors of thermal ablation-induced CANS changes, as assessed via variations in heart rate (HR) postablation. Consecutive paroxysmal AF patients undergoing first-time PV isolation by the cryoballoon (CB) or radiofrequency balloon (RFB) within a 12-month time frame and with preprocedural cardiac computed tomography (CT), were evaluated. Preablation and 24-h postablation electrocardiograms in sinus rhythm were collected and analyzed to assess HR. Anatomic evaluation by CT included the measurement of the shortest distance between the SVC and RSPV ostium (RSPV-SVC distance). A total of 97 patients (CB, n = 50 vs. RFB, n = 47) were included, with similar baseline characteristics between both groups. A significant HR increase postablation (ΔHR ≥ 15 bpm) occurred in a total of 37 patients (38.1%), without difference in number of patients between both thermal ablation technologies (CB, 19 [51%]), RFB, 18 [49%]). Independent predictors for increased HR were RSPV-SVC distance (odds ratio [OR]: 0.49, CI: 0.34-0.71, p value < .001), and age (OR: 0.94, CI: 0.89-0.98, p value = .003). Thermal balloon-based PV isolation influences the CANS through its effect on the RAGP, especially in younger patients and patients with shorter RSPV-SVC distance.

Blood pressure variability as a risk factor of recurrent paroxysmal atrial fibrillation after catheter ablation.

Blood pressure variability has been found to be a predictor of a stroke, heart failure, and ischemic heart disease that is independent of blood pressure control. This study used the variability independent of the mean (VIM) to evaluate the visit-to-visit blood pressure variability in patients previously undergoing catheter ablation (CA) of paroxysmal atrial fibrillation (PAF), and its relationship with AF recurrence was examined. The subjects were 274 consecutive PAF patients who underwent CA at our hospital. Finally, 237 subjects were included in the analysis. The mean follow-up period was 29.6 months, during which 37 subjects had recurrences, and 200 did not. During the outpatient blood pressure examinations, the VIM of the systolic blood pressure (VIM SBP) was significantly higher in the recurrence group, suggesting that blood pressure variability is associated with recurrence. The Cox proportional hazards ratio of the VIM SBP was significantly higher in the recurrence (4.839) than no-recurrence group, even after an adjustment, suggesting that the extent of the variability was a risk factor of recurrence post-CA. In addition, the Cox proportional hazard ratio for recurrence was significantly lower in the patients taking dihydropyridine calcium channel blockers, suggesting that the risk of recurrence may differ depending on the type of antihypertensive drug. Blood pressure variability may be a risk for AF recurrence after CA.

Preventing vagal response during pulmonary vein isolation with pulsed field ablation: impact of the order of the targeted pulmonary veins

Abstract Background Vagal responses are frequently observed during pulmonary vein isolation (PVI). Radiofrequency ablation of the anterior right ganglionated plexus (ARGP) before PVI has been demonstrated to effectively prevent VR occurrence. Pulsed-field ablation (PFA) has emerged as an alternative energy source for PVI. Despite PFA being selective for the myocardium, intraprocedural VRs and reversible effects on ganglionated plexi (GP) have been documented during PVI. Purpose We aimed to investigate whether initiating PVI from the right superior pulmonary vein (RSPV) before any other pulmonary veins (PVs) could prevent VR occurrence via concomitant transient ARGP modulation. Methods 60 consecutive paroxysmal atrial fibrillation patients undergoing PVI with the pentaspline PFA ablation catheter were prospectively included. In the first 30 patients, PVI was started from the left superior pulmonary vein (LSPV-first group). In the last 30 patients, the RSPV was targeted first, followed by the left PVs, and finally the right inferior PV (RSPV-first group). VR was defined as sinus bradycardia (&amp;lt;40 beats/min), asystole, or atrioventricular block (AVB). Heart rate (HR) was evaluated at baseline, during PVI, and post-ablation to assess GP modulation. Results Baseline characteristics were similar between the two study groups. VR during PVI occurred in 22 (73%) patients in the LSPV-first group and 3 (10%) in the RSPV-first group (Figure1, p&amp;lt;0.001). A higher rate of VRs was observed in patients in the LSPV-first group compared to patients in the RSPV-first group during ablation of the LSPV and LIPV (73% vs. 7%, p&amp;lt;0.001 and 27% vs. 0%, p=0.005, respectively), while no differences were found during ablation of the right PVs. Temporary pacing was employed in 10 (33%) patients in the LSPV-first group and 3 (10%) in the RSPV-first group (p=0.028). RSPV isolation induced similar acute HR increase in the two groups (13±9 bpm vs 13±10 bpm, p=0.9). However, no significant HR variation was documented in both groups at the end of the procedure compared to baseline (all p&amp;gt;0.05). Conclusion PVI with PFA is frequently associated with intraprocedural VRs when ablation is initiated from the LSPV. However, an RSPV-first approach determined transient HR increase and reduced VR occurrence.Figure 1

Heart rate dynamics after pulmonary vein isolation: pulsed-field vs. radiofrequency ablation

Abstract Background The autonomic nervous system (ANS) plays a pivotal role in the onset and maintenance of atrial fibrillation (AF). During thermal ablation, the epicardial ganglionated plexi (GP) can inadvertently be affected, as indicated by a post-ablation increase in heart rate (HR), potentially impacting post-procedural outcomes. Pulsed-field ablation (PFA) offers a safer and potentially more effective alternative, as lesion transmurality is not inversely related to safety as in thermal ablation. However, PFA's tissue selectivity may limit its effectiveness in ablating potential AF triggers like GP. Purpose We aimed to assess the impact of PF and RF energy on GP ablation by examining HR changes following PVI procedures. Methods We examined consecutive paroxysmal AF patients undergoing PVI at a single center, using either a variable-loop circular PFA catheter, as part of the inspIRE trial, or a conventional point-by-point RF catheter (1:2 ratio). ECGs were collected before and after ablation at multiple time points, including 1-hour, 1-day, 1-month, and 3-month intervals, with a 24-hour Holter ECG at 3 months. Patients without obtainable sinus rhythm ECGs at these time points were excluded. We also gathered data on post-ablation antiarrhythmic drug and beta-blocker usage. Data are reported as mean±SD, and analysis employed Student’s t-tests, paired t-tests, chi-squared tests, and multiple linear regression analysis to identify influencing factors. Results A total of 105 patients were included (PF = 35, RF = 70). Baseline demographics were similar (Table A). In the RF group, HR significantly increased at all measured time-points. In contrast, this trend was not observed in the PF group (Figure A and B). Following the procedure, the RF cohort exhibited a significantly higher HR compared to PF (7.3±10.3 vs. 0.8±11 at 1-day, p=0.018), and this difference persisted after 3 months (8.5±10.1 vs. 0.9±9, p&amp;lt;0.001, Figure C). These findings remained consistent when HR was assessed using Holter ECG data (HR at 3 months: mean 72.1±8.8 vs 65.8±9.4, min 55.2 vs 48.9; p=0.002, p=0.001, Figure D). The use of RF energy was the only predictor of HR increase after the ablation procedure (β = 7.687, p &amp;lt; 0.001, Table B). Conclusion Our findings indicates that PFA does not increase resting HR as seen with thermal RF ablation, suggesting limited effect on ANS modulation. The role of adjunctive GP ablation during PVI procedures remains a topic of debate.While PFA shows promising improvement in lesion durability, current evidence does not conclusively establish its advantage over RF. This invites contemplation about whether the addition of GP ablation in RF procedures could be a contributing factor. The absence of HR acceleration may pose issues for patients with sick sinus syndrome or pure vagally mediated AF. Further research is essential to confirm these findings and their clinical implications.Central illustrationTables

Impact of inter-lesion distance and first-pass isolation on outcomes of pulmonary venous isolation for paroxysmal atrial fibrillation.

Contiguity of ablation lesions is a critical determinant of success for paroxysmal atrial fibrillation (PAF) ablation. Evidence supports maintaining an inter-lesional distance (ILD) ≤ 6mm during pulmonary venous isolation (PVI). Meanwhile, first-pass isolation (FPI) on PVI outcome in follow-up was not deeply studied. The impact of ILD and FPI on PAF ablation outcomes was investigated. Consecutive PAF patients who underwent first-time antral PVI were recruited. Coordinates of ablation points were extracted from the electro-anatomical mapping system and analyzed using custom-developed software to determine the ILD. A gap is defined as ILD greater than 6mm. FPI was defined as the achievement of PVI by encircling the ipsilateral veins while simultaneously recording their electrical activity using a multipolar catheter. The primary endpoint was freedom from documented atrial arrhythmias including AF, atrial tachycardia (AT), or atrial flutter (AFL) lasting longer than 30s during follow-up. A total of 105 patients underwent first-time antral PVI. During 13.3 ± 0.6months of follow-up, atrial arrhythmias recurrence was noted in 22.9% of the patients. Atrial arrhythmia recurrence was significantly higher in patients with more gaps (> 2) (37.0% versus 11.9%, P < 0.01), and the number of gaps was an independent predictor of AF/AT/AFL recurrence. (Hazard ratio [HR] 1.20, 95% CI 1.03-1.40, P = 0.02). The group with FPI for at least one ipsilateral pair of PVs exhibited a decreased number of gaps (2.0 versus 7.0, P < 0.01) and demonstrated a significant correlation with a reduction of recurrence (HR 0.26, 95% CI 0.09-0.71, P = 0.01). Among 16 patients who underwent repeat ablation, the number of gaps during the index PVI was associated with PV reconnection (PVR) (P < 0.01). Gaps created during PVI are a modifiable determinant of AF/AT/AFL recurrence, and avoidance of gaps is crucial to improve clinical outcomes of PAF ablation. In addition, FPI exhibited a strong predictive capability for clinical success in patients with PAF.

Abstract 16400: Development of Deep Neural Network Models for Identification of Pulmonary Vein Potentials From Body Surface Electrocardiograms of Patients With Atrial Fibrillation

[Background] Pulmonary vein (PV) potential is essential as the origin of atrial fibrillation (AF). However, no established method exists to evaluate PV potentials on a body surface ECG (BS-ECG). [Objective] To develop a method to identify PV potentials from BS-ECGs using state-of-the-art deep neural network (DNN) technology. [Methods and results] A cohort of 799 consecutive paroxysmal AF patients, who underwent Pulmonary Vein Isolation (PVI), were enrolled, and pre- and post-PVI 12-lead ECGs (12ECGs) were collected, amounting to a dataset of 1598 ECGs. Four DNN models were constructed, each employing distinct architectures: 1D-ResNet, 1D-DenseNet, 1D-EfficientNet-b3, and 1D-ViT (Vision Transformer). These models were rigorously trained and evaluated for the identification of PV potentials. The 1D-EfficientNet-b3-based model exhibited optimal performance, achieving an accuracy of 89.4% in the training set and 89.1% in the test set. The Gradient-weighted Class Activation Mapping (Grad-CAM) effectively demonstrated that the segments 200-300ms before the P-wave is crucial for identifying PV potentials. Furthermore, DNN models were developed for each single-lead ECG. While there were variations in the accuracy of PV potential identification among single-lead models, the V6-lead model demonstrated superior performance with an accuracy of 83.2%. [Conclusions] The findings of this research strongly suggest that our DNN-based model can accurately differentiate PV potentials from BS-ECGs. Additionally, Grad-CAM visualizations indicate that pertinent features for the identification of PV potentials are predominantly clustered in the P-wave frontal region. This signifies a promising advancement in the non-invasive detection and analysis of PV potentials, paving the way for improved management of paroxysmal AF.

Impact of pre-ablation left appendage flow velocities on long term recurrence of catheter ablation for paroxysmal atrial fibrillation.

Despite undergoing a single ablation, many patients with paroxysmal atrial fibrillation (PAF) experience a gradually increasing recurrence rate. This study aims to examine the relationship between left atrial appendage emptying velocity (LAAeV) and filling velocity (LAAfV) profiles and 3-year recurrence of AF after ablation. We conducted a prospective study of 658 consecutive PAF patients who underwent their first ablation between January 2018 and December 2019. We collected the clinical and echocardiographic characteristics of the patients. LAAeV and LAAfV were obtained from a transesophageal echocardiogram (TEE) before catheter ablation. Patients were followed at regular intervals to monitor for the primary outcome of AF recurrence. After a median follow-up period of 35.3 months (range, 10.7-36.3), 288 patients (43.8%) experienced AF recurrence after catheter ablation. Patients who experienced AF recurrence had decreased LAAeV and LAAfV (LAAeV: 56.5±21.2vs. 59.6±20.7cm/s, p=.052; LAAfV: 47.5±17.9vs. 51.7±18.2, p=.003). Kaplan-Meier analysis showed that patients in the low LAAeV(<55cm/s) group had a poorer event-free survival rate than those in the high LAAeV (≥55cm/s) group (log-rank p=.012). Patients with LAAfV<48cm/s had a significantly higher risk of AF recurrence than those with LAAfV ≥48cm/s (log-rank p=.003). In the multivariable model, low LAAfV pre-ablation in TEE-guided was significantly independently associated with 3-year recurrence after single radiofrequency ablation in patients with PAF, along with LA dimension and duration of AF. This study found an independent association between low LAAfV pre-ablation in TEE-guided and 3-year recurrence after single radiofrequency ablation in patients with PAF.

Comparison of efficacy of pulmonary vein isolation between cryoballoon ablation and high-power short-duration ablation

BackgroundHigh-power short-duration (HPSD) and cryoballoon ablation (CBA) has been used for pulmonary vein isolation (PVI). ObjectiveWe aimed to compare the efficacy of PVI between CBA and HPSD ablation in patients with paroxysmal atrial fibrillation (PAF). MethodsWe retrospectively analyzed 251 consecutive PAF patients from January 2018 to July 2020. Of them, 124 patients (mean age 57.2 ± 10.1 year) received HPSD and 127 patients (mean age 59.6 ± 9.4 year) received CBA. In HPSD group, the radiofrequency energy was set as 50 W/10 s at anterior wall and 40 W/10 s at posterior wall. In CBA group, 28 mm s generation cryoballoon was used for PVI according the guidelines. ResultsThere was no significant difference in baseline characteristics between these 2 groups. The time to achieve PVI was significantly shorter in cryoballoon ablation group than in HPSD group (20.6 ± 1.7 min vs 51.8 ± 36.3, P = 0.001). The 6-month overall recurrence for atrial tachyarrhythmias was not significantly different between the two groups (HPSD:14.50% vs CBA:11.0%, P = 0.40). There were different types of recurrent atrial tachyarrhythmia between these 2 groups. Recurrence as atrial flutter was significantly more common in CBA group compared to HPSD group (57.1% vs 12.5%, P = 0.04). ConclusionIn PAF patients, CBA and HPSD had a favourable and comparable outcome. The recurrence pattern was different between CBA and HPSD groups.

90 vs 50-Watt Radiofrequency Applications for Pulmonary Vein Isolation: Experimental and Clinical Findings.

Fifty-watt radiofrequency applications have proven to be safe and efficient for pulmonary vein isolation (PVI). However, as PV reconnection still occurs and ablation catheter instability significantly contributes to suboptimal lesion formation, a new ablation catheter capable of delivering 90 W for 4 seconds only has been developed with the aim of improving PVI outcomes. In this setting, we sought to determine whether 90 W applications create transmural lesions without collateral damage experimentally and whether they can safely improve PVI procedures clinically compared with 50 W settings. Experimentally, individual lesions were created in vivo in the right atrium of 6 swine with 90 W-4 seconds applications using the SmartTouch-SF catheter in a power-controlled mode (3 animals) or the QDOT-MICRO catheter in a temperature-controlled mode (3 animals). Clinically, PVI was performed in a homogenous population of 150 consecutive paroxysmal atrial fibrillation patients using CARTO and the QDOT-MICRO catheter in a temperature-controlled mode (75 patients 50 W-ablation index-guided and 75 patients 90 W-4 seconds). Mostly, (94.9%) experimental lesions were transmural in the thin-walled right atrium of swine. However, collateral damage was observed with both catheters in 17.9% of lesions. Clinically, 90 W procedures had a lower first-pass PVI rate (49% versus 81%, P<10-4) and a higher acute PV reconnection rate (21% versus 5%, P=0.004) than 50 W procedures, whereas total procedural duration (62 versus 66 minutes, P=0.09), 1-year sinus rhythm maintenance (88% versus 90%, P=0.6) and safety (1 tamponade per group) were similar in both groups. Experimentally, using the QDOT-MICRO catheter, 90 W-4 seconds lesions are mostly transmural in the thin-walled right atrium of swine (median depth 1.87 mm) with a moderate lesion diameter of 6.62 mm but retain the potential for collateral damage. Clinically, 90 W-4 seconds applications are associated with a lower first-pass PVI rate and a higher acute PV reconnection rate than 50 W applications but similar safety outcomes and effectiveness at 1 year.

The predictive value of galectin-3 levels on left atrial low voltage areas assessed by high-density mapping in patients with paroxysmal atrial fibrillation.

AimsGalectin‐3 is an inflammation biomarker that is associated with atrial fibrosis and plays a role in the development of atrial fibrillation (AF). Low voltage areas (LVAs) identified using an electroanatomical mapping system represent the presence of fibrotic tissue. The present study aimed to determine the relationship between coronary sinus (CS) serum sampling of galectin‐3 levels and the presence and extent of LVA in patients with paroxysmal AF.MethodsA total of 115 consecutive paroxysmal AF patients underwent pulmonary vein isolation (PVI) included prospectively in the study. Voltage mapping was performed before PVI during sinus rhythm guided by multipolar high‐density mapping catheter and LVAs were defined as regions where bipolar peak to peak voltage was <0.5 mV. Galectin‐3 levels were measured via enzyme‐linked immunosorbent assay.ResultsCS serum sampling of galectin‐3 levels was significantly higher in paroxysmal AF patients with LVA than those without LVA (16.5 ± 3.7 ng/ml vs. 10.2 ±2.7 ng/ml, respectively, p < .001). CS serum sampling of galectin‐3 levels was significantly higher in paroxysmal AF patients with moderate and severe LVA than in paroxysmal AF patients with mild LVA (17 ± 3.5 ng/ml and 20.1 ± 1.3 ng/ml vs. 13.3 ± 2.3 ng/ml, respectively, p = .002). In the multivariate analysis female gender (odds ratio [OR] = 7.537, 95% confidence interval [CI]: 1.011–56.195; p = .049), left atrium volume (OR = 1.326, 95% CI: 1.052–1.67; p = .017), and CS serum sampling of galectin‐3 levels (OR = 1.704, 95% CI: 1.169–2.483; p = .006) were significant and independent predictors for LVAs.ConclusionIn this study, we found that the CS serum sampling of galectin‐3 levels increased with the extent of LVA and was an independent predictor for the presence of LVA.

New Minimally Invasive and Tailor-Made Strategy for Cryoballoon Ablation in Patients With Paroxysmal Atrial Fibrillation

The optimal dosage for cryoballoon ablation (CBA) of atrial fibrillation (AF) is still unknown. This study aimed to evaluate the clinical implications of a reduction in the freezing duration to <180 seconds during CBA guided by the time to the target temperature. This study enrolled 325 consecutive paroxysmal AF patients who underwent CBA. It was a retrospective observational study in a single centre. It compared 164 patients who underwent a tailor-made CBA procedure (group T) with 161 who had a standard CBA procedure (group S). In group T, the freezing duration was reduced to 150 seconds when the temperature reached ≤ -40 °C within 40 seconds. Furthermore, it was reduced to 120 seconds when it reached ≤ -50 °C within 60 seconds. In the other patients, the freezing duration was 180 seconds, except for excessive freezing of ≤ -60 °C and/or emergent situations while monitoring the oesophageal temperature, and for phrenic nerve injury, as in group S. In group T, 89 patients (83%) underwent CBA with a reduction in the freezing duration. The total freezing time for each pulmonary vein was significantly shorter in group T than group S, and the total procedure time in group T decreased by an average of 4 minutes compared with group S. The rate of requiring additional radio frequency ablation following the CBA was significantly lower in group T than group S. The AF-free survival rate during the follow-up period (median, 366 days) was similar between the two groups. The safety and efficacy of the new CBA strategy were non-inferior to the standard procedure.

B-PO04-114 EFFECT OF SINUS NODE DYSFUNCTION ON RECURRENCE OF ATRIAL FIBRILLATION IN PATIENTS UNDERGOING PULMONARY VEIN ANTRUM ISOLATION

Atrial Fibrillation (AF) is the most common arrhythmia. Patients with AF refractory to medical therapy undergo pulmonary vein antrum isolation (PVAI). Long term rhythm control post procedure remains a challenge. To elucidate the role of baseline sinus node dysfunction (SND) in recurrence of AF post-PVAI. Baseline, and follow-up data for patients with paroxysmal AF (PAF) undergoing PVAI at a single tertiary care center between 2004-2019 was collected. ECG and holter monitoring were done at 1, 3, 6, and 12 months post procedure. Episodes recorded during the blanking period (<3 months) were considered early (ER), while those occurring after were noted as late recurrence (LR). To assess the impact of SND, a multivariate logistic regression model was constructed. Kaplan-Meier analysis was done to examine the overall AF-free survival in each group (SND vs No-SND). Overall, 1,529 consecutive PAF patients (female: 38.2%, mean age: 60.6±10.7 years, mean follow-up time: 22.3±17.4 months, SND: 7.8%) were included in the study. Rate of ER and LR was significantly higher in patients with SND (ER: 51 (44%) vs 400(30%), P=0.002 and LR: 79 (68.1%) vs 524 (41%), P<0.001). After controlling for age, sex, diabetes, hypertension, left atrial size, and ejection fraction, SND emerged as the independent predictor of both early and late AF recurrence (ER: OR=1.8 (1.2-2.7)) and LR: OR=3.0 (1.9-4.5)). Similarly, patients with SND had significantly lower 1-year AF-Free Survival compared to those without (ER: 57% vs 70%, P<0.002 and LR: 52.5% vs 70.1%, <0.001). Sinus Node Dysfunction is an important prognostic marker for PVAI success, and AF recurrence post ablation.

B-PO04-106 IMMEDIATE AND SHORT-TERM SUCCESS RATE OF LSI GUIDED HIGH-POWER SHORT-DURATION ABLATION IN CHINESE PAROXYSMAL ATRIAL FIBRILLATION PATIENTS

The safety and efficacy of high-power short-during (HPSD) ablation guided by LSI in Chinese paroxysmal atrial fibrillation (PAF) patients remains unknown. To study the safety, efficacy and short-term success rate of LSI guided HPSD ablation in Chinese PAF patients. In 2020, totally 56 consecutive PAF patients who underwent LSI guided HPSD ablation using TacticathTM ablation catheter were enrolled. The ablation power was 50W, and the ablation end point was the preset LSI (5.0 for anterior wall and 4.0 for posterior wall). The average procedure time, average left atrium operation time and average ablation time were 114.27±45.81 minutes, 76.35±45.21 minutes, and 1514.02±396.05 seconds, respectively. The average X-ray fluoroscopy dose was 163.56±86.7mGr, and the average X-ray fluoroscopy time was 518.18±192.10s. The pulmonary veins were divided into 9 segments. Figure 1 shows the average contact force (CF), ablation duration(D) and LSI in different PV segments. The average LSI of the ridge and left anterior wall did not reach the preset value of 5.0, which were 4.5±0.35 and 4.58±0.37, respectively. The immediate success rate of the procedure was 100%, and the first round RPV and LPV isolation rate was 92.86% and 75%, respectively. In the 6-month follow up, the no recurrence rate of AF was 92% (23/25). There were 4 steam pops during the procedure with no further complications. LSI guided High-power short-duration ablation in Chinese PAF patients is efficient and with a very low complications rate.

High-Normal Thyroid Function and Recurrence of Atrial Fibrillation after Catheter Ablation: A Prospective Observational Study

Background: Thyroid function is increasingly recognized as an important modifiable factor for atrial fibrillation (AF); however, it is unclear if the changes in thyroid hormones, even within the normal range, are associated with AF recurrence after catheter ablation. Methods: Consecutive paroxysmal AF patients who underwent catheter ablation were enrolled. Patients with abnormal thyroid hormones or previous thyroid illnesses were excluded. Patients were followed for 12 months or until they presented with the first episode of atrial tachyarrhythmia after a blanking period. Results: The study included 448 patients with a mean age of 61 (14) years, and 46% were women. After a 1-year follow-up, 104 (23.2%) patients experienced atrial tachyarrhythmia recurrences after an ablation procedure. Recurrence was significantly different among quartile groups of thyroid function, with highest FT₄ and FT₃ levels associated with the greatest risk of recurrence (p < 0.001 and p = 0.024, respectively). FT₄ and FT₃ levels were independent predictors of atrial tachyarrhythmia recurrence (hazard ratio 1.07 per 1 pmol/L increase in FT₄, 95% confidence interval [CI] 1.01–1.15, p = 0.036 and 1.31 per 1 pmol/L increase in FT₃, 95% CI 1.01–1.71, p = 0.032). Conclusions: High-normal FT₃ and FT₄ levels are associated with AF recurrence after catheter ablation in this Chinese population. Attention to thyroid hormones could be valuable to assist in the management of AF.

Difference of myocardial injury, inflammation and early recurrence after pulmonary vein isolation among laser balloon ablation, radiofrequency catheter ablation and cryoballoon ablation

Abstract Background Pulmonary vein isolation (PVI) has become well-established as the main therapy for patients with drug-refractory paroxysmal atrial fibrillation (PAF) and various isolation methods including radiofrequency ablation (RFA), cryoballoon ablation (CBA) and laser balloon ablation (LBA) were available. Pathological findings in each ablation methods such as myocardial injury and inflammation are thought to be different. High sensitive cardiac troponin I (hs-TnI), subunit of cardiac troponin complex, is a sensitive and specific marker of myocardium injury. High-sensitive C-reactive protein (hs-CRP) is a biomarker of inflammation and is elevated following cardiomyocyte necrosis. Relationship between myocardial injury and inflammation after ablation using RFA, CBA and LBA and early recurrence of atrial fibrillation (ERAF) remains unclear. Methods We enrolled consecutive PAF patients from Osaka Rosai Atrial Fibrillation (ORAF) registry who underwent PVI from January 2019 to October 2019. We compared the clinical characteristics including age, gender, hypertension, diabetes mellitus, history of heart failure, CHADS2Vasc score, renal function, serum BNP level and echocardiographic parameters including left ventricular dimensions, left atrial diameter (LAD) and left ventricular ejection fraction (LVEF) between RFA, CBA and LBA groups. We investigated the difference of relationship between myocardial injury marker (hs-TnI), inflammation markers (white blood cell change (DWBC) from post to pre PVI, neutrophil-to-lymphocyte ratio change (DNLR) from after to before PVI and hs-CRP) at 36–48 hours after PVI and ERAF (&amp;lt;3 months after PVI) between each group. Results We enrolled 187 consecutive PAF patients who underwent PVI. RFA, CBA and LBA groups comprised 108, 57 and 22 patients, respectively. There were no significant differences of age, gender, hypertension, diabetes mellitus, history of heart failure, CHADS2Vasc score, renal function, serum BNP level and echocardiographic parameters between each group. Serum hs-TnI in RFA group and LBA group were significantly lower than in CBA group (2.643 ng/ml vs 5.240ng/ml, 1.344 ng/ml vs 5.240 ng/ml, p&amp;lt;0.001, p=0.002, respectively, Figure). DWBC was significantly higher in LBA group than CBA group (1157.3/μl vs 418.4/μl, p=0.045). DNLR did not differ between each group. Hs-CRP in RFA group and LBA group were significantly higher than in CBA group (1.881 mg/dl vs 1.186 mg/dl, 2.173 mg/dl vs 1.186 mg/dl, p=0.010, p=0.003, respectively, Figure). Incidence of ERAF was significantly higher in LBA group than RFA group (36.4% vs 16.7%, p=0.035). Incidence of ERAF tended to be higher in LBA group than CBA group (36.4% vs 19.3%, p=0.112). Conclusion LBA may cause less myocardial injury than RFA and CBA, on the contrary LBA may cause more inflammation than CBA. Incidence of ERAF in LBA was highest between each procedure. Inflammation markers and ERAF Funding Acknowledgement Type of funding source: None

Pulmonary vein volume and myocardial sleeve extension estimated by 3D computed tomography and voltage mapping predict arrhythmogenic triggers of paroxysmal atrial fibrillation

Relationship between pulmonary vein (PV) anatomy and the pathophysiology of paroxysmal atrial fibrillation (PAF) remains incompletely studied. The aim of this study was to determine whether PV anatomy predicts arrhythmogenic PVs. Twenty-six consecutive PAF patients with spontaneous PAF or consistently frequent ectopic beats during electrophysiological study were enrolled. Computed tomography (CT) images for PVs were reconstructed into 3D images. The PV diameter and volume were measured based on the 3D images. The PV myocardial sleeve area was measured based on the 3D voltage mapping results. The PV myocardial sleeve area index was calculated by dividing the sleeve area of each PV by the average sleeve area of all PVs in each patient. The diameter and volume of the arrhythmogenic PVs were larger than those of the non-arrhythmogenic PVs (21.08 ± 4.57mm vs. 16.47 ± 3.31mm, P < 0.001 and 7.70 ± 3.28cm3 vs. 4.09 ± 1.99cm3, P < 0.001, respectively). The myocardial sleeve area and sleeve area index of the arrhythmogenic PVs were also larger than those of the non-arrhythmogenic PVs (8.62 ± 5.33cm2 vs. 4.77 ± 3.84cm2, P < 0.001 and 1.59 ± 0.35 vs. 0.81 ± 0.38, P < 0.001, respectively). Multivariate analysis showed the PV myocardial sleeve area index was the independent predictor for arrhythmogenic PVs (P < 0.001). PV size plays an important role in triggering PAF. A large myocardial sleeve extension is a powerful and independent predictor for arrhythmogenic PV, which may be useful anatomical markers to facilitate PAF ablation.

Predictors of non-pulmonary vein foci in paroxysmal atrial fibrillation.

Progress of balloon devices for pulmonary vein (PV) isolation in atrial fibrillation (AF) has been remarkable. However, these techniques were specialized in pulmonary vein treatment; predicting non-PV foci in advance is important to decide the treatment strategy. In this study, we investigate the predictors for paroxysmal AF. Subjects were consecutive paroxysmal AF patients who underwent high-dose isoproterenol provocation after PV isolation in the first session. The PV group (n = 102) and non-PV group (n = 222) were defined as the patients with and without non-PV ablation, respectively. Non-PV ablation was performed when frequent repetitive premature atrial contractions or triggered AF occurred spontaneously or by isoproterenol provocation. Predictors of non-PV origin in paroxysmal AF patients were examined using clinical characteristics and preoperative echocardiography. In the multivariate logistic regression analysis, female sex, body mass index (BMI < 23.8), absence of hypertension, and higher ratio of mitral early diastolic peak (E-wave) to early diastolic mitral annulus peak (e') velocity (E/e' > 8.44) were significant independent predictors of non-PV foci (hazard ratio 2.04, 1.88, 3.63, and 2.33; 95% confidence interval 1.17-3.55, 1.05-3.39, 1.72-7.67, and 1.34-4.05; p = 0.011, 0.035, < 0.001, and 0.003, respectively). If a patient had these four factors, non-PV was detected with 96.8% specificity. Female sex, lower BMI, absence of hypertension, and higher E/e' were significant indicators of non-PV foci in patients with paroxysmal AF. Reviewing these factors in advance may be useful for selecting a device to perform pulmonary vein isolation.

Real-world investigation on discontinuation of oral anticoagulation after paroxysmal atrial fibrillation catheter ablation in China.

To find out the real-world investigation on discontinuation of oral anticoagulation after paroxysmal atrial fibrillation (AF) catheter ablation China. We enrolled in our study 1,508 consecutive paroxysmal AF patients who underwent catheter ablation from five centers. Patients' clinical data and follow-up data were collected. Clinical data included on-admission characteristics such as gender, age, type and duration of AF, type of ablation, ablation sessions, history of diseases, CHA2DS2-VASc score, echocardiographic variables, medication, and blood test variables. Follow-up data included duration of follow-up, the status of oral anticoagulant (OAC) therapy, adverse events, and recurrence of AF. A total of 1,491 patients were included in the final analysis, while the other 17 patients lost contact. The follow-up duration was 12 to 74 months (27.8±14.6 months). Of 1,491 patients, 989 (66.3%) patients stopped OAC therapy 3 to 14 months after successful ablation during follow-up. Stroke or transient ischemic attack (TIA) occurred in 37 (2.5%) patients. Major bleeding occurred in 24 (1.6%) patients. Six (0.4%) patients died at follow-up. Patients who stopped OAC had lower CHA2DS2-VASc score (1.5±1.4 vs. 2.4±1.7, P<0.05) and lower incidence of major bleeding (11/989 vs. 13/502, P<0.05). Of 989 patients who stopped OAC, 318 stopped according to doctor's prescription, and 671 stopped on their own decision. In patients who underwent brain MRI, patients who stopped OAC had a lower incidence of silent cerebral infarction (SCI) (37/904 vs. 38/419, P<0.05). Among patients who did not stop warfarin therapy, there were 117 (117/397, 29.5%) patients had not to achieve target INR. The incidence of adverse events was relatively low in paroxysmal AF patients who stopped OAC. The patient partly determined when OAC was discontinued. Target INR was not achieved in many patients who had not to stop OAC.

Effect of Combined Pulmonary Vein and Superior Vena Cava Isolation on the Outcome of Second Catheter Ablation for Paroxysmal Atrial Fibrillation

Recurrence of paroxysmal atrial fibrillation (AF) is partly due to pulmonary vein (PV) reconnection and non-PV foci, especially superior vena cava (SVC). We aimed to investigate the efficacy and safety of empiric SVC isolation plus PV isolation after first failed radiofrequency ablation involving only PV isolation for paroxysmal AF. Procedural and follow-up outcomes of ablation for 144 consecutive paroxysmal AF patients after first failed radiofrequency ablation involving only PV isolation were retrospectively compared between patients undergoing either conventional SVC isolation (additional SVC isolation if SVC-triggered AF or rapid SVC activity was observed; n = 72) or empiric SVC isolation after PV isolation (n = 72). In conventional SVC isolation versus empiric SVC isolation groups: baseline characteristics and proportion of recorded PV electrical potentials were similarly distributed and all pulmonary veins were successfully reisolated; SVC isolation was performed less often (6 [8.3%] vs 70 [97.2%]; p <0.001, respectively); and during 19 ± 10 months follow-up, atrial tachyarrhythmias recurrence-free rate after a second procedure was lower (58.3% vs 77.8%, log rank; p = 0.037). Multivariate regression analysis revealed LA diameter ≥45 mm (odds ratio [OR] = 2.5; 95% confidence interval [CI], 1.4 to 4.6; p = 0.002) as the independent risk factor of atrial tachyarrhythmias recurrence and empiric SVC isolation (OR = 0.47; 95% CI, 0.25 to 0.87; p = 0.016) as the independent protector against atrial tachyarrhythmias recurrence after a second ablation procedure. Empiric SVC isolation plus PV isolation did not increase significantly procedural time or complications. In conclusion, the strategy of empiric SVC isolation plus PV isolation during a second procedure for paroxysmal AF improved atrial tachyarrhythmias recurrence-free rate without increasing procedural time or complications.

P4760New minimally invasive and tailor-made strategy for cryoballoon ablation in patients with paroxysmal atrial fibrillation

Abstract Background Currently, cryoballoon ablation (CBA) has proven to be highly effective in achieving free from atrial fibrillation (AF), especially paroxysmal AF. However, the optimal freezing protocol for each patient to achieve successful pulmonary vein isolation by only CBA is still uncertain. The aim of this study was to evaluate the clinical implications of a reduction in the freezing duration (&lt;180s) during CBA guided by the time to target temperature. Methods From November 2015 to August 2018, 286 consecutive paroxysmal AF patients undergoing CBA were enrolled. We compared 107 patients undergoing a tailor-made CBA procedure (Group A; August 2017-August 2018) to 179 patients with a standard CBA procedure (Group B; November 2015–July 2017). In Group A, the freezing duration was reduced to 150s when the temperature reached ≤−40°C within 40s. Furthermore, we reduced it to 120s when it reached ≤−50°C within 60s. In the other patients, the freezing time was 180s except for excessive freezing over −60°C and/or emergent situations while monitoring the esophageal temperature and for phrenic nerve injury as in Group B. Results The baseline clinical characteristics were similar between two groups. In Group A, 89 patients (83%) underwent CBA with a reduction in the freezing time. The rate of having reduction time in left inferior PV (LIPV) and right inferior PV (RIPV) was lower compared with left superior PV (LSPV) and right superior PV (RSPV) (respectively 17%, 29%, 56%, and 63.5%). However, for right inferior PV, in 31 patients having the reduced freezing time, none of them required touch-up ablation. Although the procedure time and frequency of touch-up ablation did not differ between the 2 groups, total freezing time for each PV was significantly shorter in Group A than Group B as shown in figure (LSPV: 164±28s vs. 216±67s; p&lt;0.001, LIPV: 187±44s vs. 218±69s; p&lt;0.001, RSPV: 147±31s vs. 192±51s; p&lt;0.001, RIPV: 180±50 vs. 218±73s; p&lt;0.001). The AF free survival rate during the follow-up period (356±167 days) was similar between the 2 groups (log-rank test, p=0.38). Furthermore, the complication rate was similar 2 groups. The freezing time for each PV Conclusion The safety and efficacy of the new tailor-made CBA strategy were non-inferior to the standard procedure. This study showed that the unnecessary freezing time could be reduced in most of paroxysmal AF patients.