Persistent Atrial Fibrillation Group Research Articles

Cryoballoon-Assisted Pulmonary Vein Isolation and Left Atrial Roof Ablation Using a Simplified Sedation Strategy without Esophageal Temperature Monitoring: No Notable Thermal Esophageal Lesions and Low Arrhythmia Recurrence Rates after 2 Years

Background: Atrial fibrillation (AF) ablation is increasingly effective for managing heart rhythm but poses risks like esophageal fistulas. Minimizing esophageal thermal lesions while simplifying procedures is crucial. Methods: This prospective study involved 100 consecutive AF patients undergoing cryoballoon ablation with simplified sedation, without esophageal temperature monitoring. Patients with paroxysmal AF (Group A) received pulmonary vein isolation only, while those with persistent AF (Group B) also had left atrial roof ablation. Gastroesophageal endoscopy was performed post-procedure to detect lesions, and cardiological follow-ups were conducted at 3, 12, and 24 months. Results: The cohort included 69% men, with a median age of 65.5 years. Post-ablation endoscopy was performed in 92 patients; esophageal lesions were found in 1.1% of Group A and none of Group B. GERD was diagnosed in 14% of patients, evenly distributed between groups and not linked to lesion occurrence. Gastric hypomotility was observed in 16% of patients, with no significant difference between groups. At 24 months, arrhythmia-free survival was 88% in Group A and 74% in Group B. Conclusion: Cryoballoon-assisted pulmonary vein isolation, with or without additional left atrial roof ablation and without esophageal temperature monitoring during a simplified sedation strategy, shows low risk of esophageal thermal injury and effective ablation outcomes.

Impact of pulmonary vein variant anatomy during cryo-ablation in paroxysmal and persistent AF patients: 1-year outcome from a nationwide multicenter clinical setting

Abstract Background Complete electrical pulmonary vein isolation (PVI) by cryo-balloon approach is a well-established ablation strategy of atrial fibrillation (AF). While contrast findings exist regarding the influence of variant pulmonary vein (PV) anatomy on predicting AF recurrence, limited data are currently available specifically for cases involving the POLARx cryoablation system during PVI. Purpose We report the real-world experience of POLARx in the context of de novo AF ablation in a multicenter Italian registry. Methods Consecutive patients undergoing AF ablation from the CHARISMA registry at 10 Italian centres were included. Protocol-directed cryoablation was delivered for 180 sec or 240 sec according to operator’s preference for isolation achieved in ≤60 sec, or 240 sec if isolation occurred >60 sec or when time to isolation was not available. The ablation endpoint was PVI as assessed by entrance and exit block. All patients were followed-up for at least 12 months after the procedure. Results Four-hundred twenty-nine patients were included (n=358, 83.4% paroxysmal AF, n=71, 16.6% persistent AF, mean age 60.7±10 years, 28.3% female, mean LVEF 58±8%). PVI was achieved in all pts using only cryoablation. Twenty-eight (6.6%) patients exhibited an anatomical variant: 17 (4.0%) a common ostium and 11 (2.6%) an adjunctive PV. The mean number of freeze applications per patient was 5.1 (1.2 for LSPV, 1.3 for LIPV, 1.2 for RSPV and 1.3 for RIPV). Over a median of 398[370-461] days of follow-up, 14 (3.2%) patients experienced an early recurrence of AF during the 90-day blanking period. Overall, 63 patients (14.7%) suffered an AF recurrence after the 90-day blanking period (median time to recurrence 342[171-381] days). The proportion of patients exhibiting AF/AT recurrences was higher in the persistent AF group (17 out 71, 23.9%) than in the paroxysmal AF group (46 out 358, 12.8%, p=0.026), with a hazard ratio of 2.02 (95%CI: 1.2 to 3.5, p=0.0137) whereas patients with anatomy variant showed a similar AF/AT recurrence rate (5 out 28, 17.9%) than in the standard anatomy group (58 out of 401, 14.5%) with a hazard ratio of 1.43 (0.6 to 3.6, p=0.441). Four (0.9%) transient phrenic nerve palsy were observed, both with full recovery in the 48-h post procedure; no major procedure-related adverse events were reported. Conclusion In this multicenter study, the cryo-balloon system demonstrated safety and efficacy in treating both paroxysmal and persistent AF patients, yielding a low incidence of AF/AT recurrence during follow-up, regardless of the presence of variant PV anatomy.

The effects of radiofrequency catheter ablation for atrial fibrillation on right ventricular function

Abstract Background The effects of radiofrequency catheter ablation (RFCA) for atrial fibrillation (AF) on right ventricular (RV) function are not well known. Methods Patients who underwent RFCA for AF and underwent pre- and post-procedural echocardiography were enrolled. Fractional area change (FAC), RV free-wall longitudinal strain (RVFWSL), and RV 4-chamber strain (RV4CSL) were measured. Changes in FAC, RVFWSL, and RV4CSL before and after RFCA were compared among paroxysmal (PAF), persistent (PeAF), and long-standing persistent AF (LSPeAF) groups. Results A total of 164 participants (74 PAF, 47 PeAF, and 43 LSPeAF; age, 60.8±9.8 years; men, 74.4%) was enrolled. The patients with PeAF and LSPeAF had worse RV4CSL (p<0.001) and RVFWSL (p<0.001) than those with PAF and reference values. Improvements in RVFWSL and RV4CSL after RFCA were significant in the PeAF group compared with the PAF and LSPeAF groups (ΔRV4CSL, 8.4% [5.1–11.6] in PeAF vs. 1.0% [-1.0–4.1] in PAF, 1.9% [-0.2–4.4] in LSPeAF, p<0.001; ΔRVFWSL, 9.0% [6.9–11.5] in PeAF vs. 0.9% [-1.4–4.9] in PAF, 1.0% [-1.0–3.6] in LSPeAF, p<0.001). Conclusions RV function is impaired in patients with PeAF and LSPeAF than in those with PAF. RV function is more improved after RFCA in patients with PeAF than in those with PAF or LSPeAF.Changes of echocardiographic parameters

Ten-year follow-up results of patients with persistent atrial fibrillation treated by combined pulmonary vein isolation and complex fractionated atrial electrocardiogram ablation

Abstract Background For persistent atrial fibrillation (AF), pulmonary vein isolation (PVI) alone is associated with lower success rate compared to paroxysmal AF and additional strategies are needed. Ablation targeting on complex fractionated atrial electrograms (CFAE) is an alternative method. Although clinical benefits of the strategy combined PVI and CFAE ablation have not been shown by large trials, clinical situations and consequences of this approach have not been clearly demonstrated during very long term follow-up. Purpose This study aimed to retrospectively investigate clinical outcomes of patients with persistent AF treated by the approach combined PVI and CFAE ablation during a follow-up period of 10 years. Methods 73 patients (59.4±8.1 years, 64 male, AF history 5.5 years) with persistent (23, 31.5%) and long-standing persistent AF (50, 68.5%) who underwent combined PVI and CFAE ablation in the first procedure were included. Structural heart disease was found in 9 patients, and a history of ablation for typical atrial flutter (AFL) in 4. A complete CFAE mapping in the left atrium and coronary sinus was performed with a 3-D mapping system (EnSite NavX). All CFAEs defined as electrograms with continuous activities or mean cycle length detected by the system <80 ms were eliminated. All patients were controlled regularly during the first year with 12-lead ECG and Holter monitoring and followed by annual control. The electronic health records for all patients were extensively investigated and the patients were interviewed in 2020-2022. Any documented atrial tachyarrhythmia (ATA) after 3-month blanking period was regarded as recurrence. Results Mean 2.2±1.2 (1-5) ablation procedures were performed in each patient. After index ablation, 18 (24.7%) were free of ATAs during 10-year follow-up. 26 (35.6%) had recurrence of only AF, 6 (8.2%) of only AFL and 23 (31.5%) had both AF and AFL. The proportion of AFL was 39.7% with 6 typical AFL. After multiple ablation procedures, 33 (45.2%) patients were free of ATA during the follow-up. 23 (31.5%) had recurrence of only AF, 5 (6.8%) of only AFL and 12 (16.4%) of both AF and AFL. The proportion of AFL was 23.2% with no typical AFL. At 1-year follow-up, freedom of ATAs in persistent AF was higher than that in long-standing AF (65.2 vs. 40.0%, p=0.033) and no significant difference was found after 2 years (47.8 vs. 34.0%, p=0.129) until 10 years (30.4 vs. 22.0%, p=0.167, Figure 1). No difference was observed between these subgroups after multiple procedures at 10-year follow-up (47.8 vs. 44.0%, p=0.708, Figure 2). Conclusions PVI plus CAFE ablation in patients with persistent AF led to a high recurrence of ATA after index ablation. Difference of ATA-freedom between persistent and long-standing persistent AF groups was found only 1 year after the index procedure, but not during further follow-up. Incidence of post-ablation AFL was particularly high, even after multiple ablation procedures.Figure 1Figure 2

The Effects of Radiofrequency Catheter Ablation for Atrial Fibrillation on Right Ventricular Function.

The effects of radiofrequency catheter ablation (RFCA) for atrial fibrillation (AF) on right ventricular (RV) function are not well known. Patients who underwent RFCA for AF and underwent pre- and post-procedural echocardiography were enrolled consecutively. Fractional area change (FAC), RV free-wall longitudinal strain (RVFWSL), and RV 4-chamber strain including the ventricular septum (RV4CSL) were measured. Changes in FAC, RVFWSL, and RV4CSL before and after RFCA were compared among paroxysmal AF (PAF), persistent AF (PeAF), and long-standing persistent AF (LSPeAF) groups. A total of 164 participants (74 PAF, 47 PeAF, and 43 LSPeAF; age, 60.8 ± 9.8 years; men, 74.4%) was enrolled. The patients with PeAF and LSPeAF had worse RV4CSL (p<0.001) and RVFWSL (p<0.001) than those with PAF and reference values. Improvements in RVFWSL and RV4CSL after RFCA were significant in the PeAF group compared with the PAF and LSPeAF groups (ΔRV4CSL, 8.4% [5.1, 11.6] in PeAF vs. 1.0% [-1.0, 4.1] in PAF, 1.9% [-0.2, 4.4] in LSPeAF, p<0.001; ΔRVFWSL, 9.0% [6.9, 11.5] in PeAF vs. 0.9% [-1.4, 4.9] in PAF, 1.0% [-1.0, 3.6] in LSPeAF, p<0.001). In patients without recurrence, improvements in RVFWSL and RV4CSL after RFCA were significant in the PeAF group compared to the LSPeAF group. RV systolic function is more impaired in patients with PeAF and LSPeAF than in those with PAF. RV systolic function is more improved after RFCA in patients with PeAF than in those with PAF or LSPeAF.

The Correlation of Inflammation, Oxidative Stress, and Hippocampal Perfusion in Patients with Atrial Fibrillation.

Atrial fibrillation (AF) is closely related to abnormal cerebral blood flow. Inflammation and oxidative stress have always been important factors in the pathophysiology of AF. It remains unknown whether inflammation and oxidative stress are correlated to hippocampal perfusion in patients with AF.Sixty-three patients with AF with normal hippocampal blood perfusion (NHBP) were compared to 71 patients with AF with abnormal hippocampal blood perfusion (AHBP) using a case-control study design. The serum levels of inflammation and oxidative stress were measured. The hippocampal perfusion was detected. (1) The serum levels of high-sensitivity C-reactive protein (hs-CRP), interleukin 6 (IL-6), and oxidized low-density lipoprotein (ox-LDL) were statistically higher in the AHBP group than in the NHBP group. In the AHBP subgroup analysis, the serum levels of hs-CRP and IL-6 were statistically higher in patients with persistent AF than those with paroxysmal AF. (2) The relative cerebral blood volume (rCBV), mean transit time (MTT), and the time-to-peak (TTP) were statistically higher in the AHBP group than in the NHBP group. Moreover, cerebral blood flow (rCBF) was statistically lower in the AHBP group than in the NHBP group. (3) relative cerebral blood volume (rCBV), rCBF, MTT, and TTP were passively associated with serum hs-CRP and IL-6; rCBV, rCBF, and MTT were positively associated with ox-LDL. The serum levels of hs-CRP, IL-6, and ox-LDL were associated with AHBP in patients with AF after multivariate logistic regression analysis.Oxidative stress and inflammatory biomarkers were increased in patients with AF with AHBP, in which the serum levels of hs-CRP and IL-6 in the persistent AF group were statistically higher than those in the paroxysmal AF group. The serum levels of hs-CRP, IL-6, and ox-LDL were associated with AHBP in patients with AF.

Role of atrial lymphatics in atrial myocardial fibrosis and atrial fibrillation: a human and mouse study

Abstract Background/Introduction Cardiac lymphatics maintain myocardial fluid and immune cell homeostasis, but its effects on atrial fibrosis and atrial fibrillation (AF) have not been clarified. Purpose To address this issue, we first evaluated the left atrial appendage (LAA) in humans histologically and biologically. We then studied mice to elucidate the mechanisms. Methods Human LAA samples were collected from 34 consecutive AF patients during cardiovascular surgery. They were assigned to the paroxysmal AF (PAF) group (n=17, 70.9±11.6 years) and the persistent AF (PeAF) group (n=17, 72.1±7.2 years). In the mouse experiments, 8-week-old male C57BL/6 mice were administrated subcutaneously with vehicle or Angiotensin II (AngII) (2.0 mg/kg/day) for 4 weeks. In some mice, VEGFC, a pro-lymphangiogenesis inducer, was administrated subcutaneously at a dose of 50 μg/kg/day simultaneously with AngII. AF was induced by transesophageal burst pacing in vivo, and by burst pacing in isolated perfused hearts using a Langendorff apparatus. Results In human LAA samples, mRNA expression of lymphangiogenesis-related genes (LYVE1, PROX1, and VEGFR3) was significantly lower in the PeAF group compared to the PAF group (p=0.037, 0.029, and 0.041). The number of LYVE1-positive atrial lymphatic endothelial cells (LECs) was also significantly lower in the PeAF group compared to the PAF group (p=0.026). There was a negative correlation between the number of LYVE1-positive atrial LECs and the area percentage of atrial myocardial fibrosis (r=-0.609, p&amp;lt;0.001). In mouse experiments, continuous infusion of AngII suppressed the mRNA expression of lymphangiogenesis-related genes, including Lyve1, Prox1, and Vegfr3 (n=6 in each group, p&amp;lt;0.001, p=0.003, and p&amp;lt;0.001, respectively). AngII infusion reduced the number of LYVE1-positive atrial LECs (p&amp;lt;0.001) and increased the mRNA expression of fibrosis-related genes (Tgfb, Col1a1, and Col3a1). The area percentage of fibrosis in atrial myocardium was also increased by AngII. Treatment with VEGFC for 4 weeks effectively reversed the effects of AngII, i.e., suppression of lymphangiogenesis-related genes expression, reduction of LYVE1-positive atrial LECs, increase in fibrosis-related genes expression, and increase in atrial fibrosis. Additionally, VEGFC treatment attenuated AngII-induced enhancement of vulnerability to AF in in vivo experiments (n=8 in each group, p=0.007) and in isolated perfused hearts (n=8 in each group, p=0.007). Conclusions Our study with human LAA demonstrated a strong association between atrial lymphatics and atrial myocardial fibrosis/progression of AF. Our mouse study showed that VEGFC reversed AngII -induced increase in atrial myocardial fibrosis and vulnerability to AF, possibly via promotion of lymphangiogenesis. Defects of lymphangiogenesis may be involved in atrial myocardial fibrosis and AF, and may be a therapeutic target for atrial cardiomyopathy.

Left atrial strain superior to structural remodeling in identifying occult atrial fibrillation.

Occult atrial fibrillation (AF) is a significant risk factor for occult stroke but is difficult to detect. Myocardial strain, based on speckle tracking echocardiography (STE), can detect subclinical changes in left atrial (LA) function. This study aimed to investigate the diagnostic value of LA strain in identifying asymptomatic AF patients with normal electrocardiograms and healthy volunteers. A total of 354 subjects were retrospectively enrolled. Patients were divided into two groups based on whether they had AF during echocardiography. Patients with sinus rhythm during echocardiography were further divided into healthy control group and occult AF group. Patients with AF during echocardiography were further divided into paroxysmal AF group and persistent AF group. LA mechanical function measured by STE was compared between patients with asymptomatic AF and volunteers. Conventional echocardiographic indicators were measured. The diagnostic value of LA strain for identifying asymptomatic AF was assessed by univariate and multivariate regression analysis and receiver operating characteristic (ROC) curves. Occult AF patients had higher NT-proBNP levels, larger RA area, larger LAVmax and decreased LAEF than control group. However, occult AF patients had lower NT-proBNP levels, RA area and LAVmax and higher LAEF than paroxysmal and persistent AF. The measured LA reservoir strain (LASr), LA conduit strain (LAScd), LA contraction strain (LASct) of occult AF group was significantly lower than that of control group. However, occult AF patients had preserved LAScd and LASct than paroxysmal and persistent AF. RA area, LAEF and LASr were remarkable correlation with occult AF after adjustment for NT-proBNP, LAVmax, and LAScd. The area under curve of ROC for LASr was the greatest among RA area, LAEF and LASr, with a cut-off value of 34.1% (sensitivity: 75.4%, specificity: 87.6%). LASr can identify occult AF in the asymptomatic population. Patients with LASr values ≤34.1% have a higher incidence of occult cardiac dysfunction. These findings help identify patients with occult AF and further risk stratification for the AF population.

Circulating Neuropeptide Y May Be a Biomarker for Diagnosing Atrial Fibrillation

Introduction: Sympathetic nervous system disorder promotes atrial fibrillation (AF), and neuropeptide Y (NPY) is an important neurotransmitter. This study aimed to explore the predictive value of plasma NPY in patients with AF. Methods: Five hundred seventy-six patients were divided into AF (including paroxysmal and long-standing persistent AF; 360) and sinus rhythm (SR) groups (216). NPY level was detected using enzyme-linked immunosorbent assay, and NPY mRNA expression level was detected using quantitative polymerase chain reaction. Logistic regression was used to analyse the risk factors for AF; the correlations between blood NPY level and age, body mass index (BMI), left ventricular ejection fraction, left atrial diameter (LAD), and European Heart rate Association (EHRA) score in patients with AF were determined. The receiver operating characteristic (ROC) curve was utilised to predict AF. Results: Plasma NPY levels were found to be higher in patients with AF than in patients with SR and in patients with long-standing persistent AF than in patients with paroxysmal AF; blood NPY mRNA levels were higher in the paroxysmal and long-standing persistent AF groups compared to the SR group (p < 0.05). Increased age {odds ratio (OR) = 1.201 (95% confidence interval [CI]: 1.01, 1.427)} and high NPY [OR = 1.239 (95% CI: 1.022, 1.501)] were factors found to affect AF detrimentally. NPY was associated with BMI (r = 0.5856, p < 0.05), LAD (r = 0.4023, p < 0.05), and EHRA score (r = 0.898, p < 0.05). The ROC curve for the predictive value of plasma NPY levels for AF showed an area under the curve (AUC) value of 0.919 (p < 0.05), while that for long-standing persistent AF showed an AUC of 0.784 (p < 0.05). Conclusion: Circulating NPY may be a promising molecular biomarker of AF.

Prognostic implication of early recurrence after cryoballoon ablation in patients with atrial fibrillation.

It remains uncertain whether the implication of early recurrence and blanking period can be applied to patients with atrial fibrillation (AF) treated with cryoballoon ablation (CBA). We aimed to explore the prognostic value of early recurrence in patients with AF treated with CBA. We studied consecutive AF patients who were treated with CBA between April 2019 and September 2020 in two tertiary medical institutes and followed for up to 12months. The endpoint was the late recurrence of atrial arrhythmia, including AF, atrial flutter, and atrial tachycardia, following a 90-day blanking period. Atrial arrhythmia during the blanking period was defined as early recurrence and was not considered as an endpoint. This study included 406 patients with AF who underwent CBA. During the follow-up, 147 (36.2%) cases of late recurrence were observed. Of the 104 patients with early recurrence, 85 experienced late recurrence during follow-up. Early recurrence was associated with an increased risk of late recurrence in the univariate and multivariate analyses (P < 0.001). When we classified the patients into paroxysmal AF and persistent AF groups, early recurrence was still significantly associated with a higher risk of late recurrence (P = 0.005 and P < 0.001, respectively). Early recurrence after CBA was an independent risk factor for late recurrence in all patients as well as in those with paroxysmal AF and persistent AF. Therefore, further prospective studies could be considered to verify the risks and benefits of early rhythm control in patients with early recurrence.

The predictive value of left atrium epicardial adipose tissue on recurrence after catheter ablation in patients with different types of atrial fibrillation

BackgroundA growing body of evidence supports that the left atrium epicardial adipose tissue (LA-EAT) is related to the occurrence and recurrence of atrial fibrillation (AF). The relationship between LA-EAT and the recurrence after radiofrequency catheter ablation (RFCA) in patients with different types of AF is still unclear. This study aims to evaluate the predictive value of LA-EAT on the recurrence of AF after RFCA in patients with different types of AF. Methods301 AF patients who underwent RFCA for the first time were divided into the paroxysmal atrial fibrillation (PAF) group (n = 181) and the persistent atrial fibrillation (PersAF) group(n = 120), which were followed up at 3, 6, and 12 months. All patients underwent left atrial computed tomography angiography (CTA) examination before the operation, and LA-EAT was measured using software (Advantage Workstation4.6, GE, USA). ResultsAfter a median follow-up of 10.7 months, 73/301 patients (24.25%) had a recurrence of AF, including 43 /120(35.83%) patients with PersAF and 30/181(16.57%) patients with PAF. In multivariable Cox regression analysis, LA-EAT volume (OR = 1.053;95%CI: 1.024–1.083, p < 0.001), attenuation (OR = 0.949;95%CI:0.911–0.988, p = 0.012) and left atrial diameter (LAD) (OR = 1.063;95%CI:1.002–1.127，p = 0.043) were independent risk factors for recurrence in patients with PersAF but not in patients with PAF. ConclusionLA-EAT volume and attenuation are independent risk factors for recurrence after RFCA in patients with PersAF.

Relationship between atrial fibrillation and a liver fibrogenesis marker in patients with acute heart failure

BackgroundHemodynamic disturbance in heart failure (HF) induces extra-cardiac organ injury. Atrial fibrillation (AF) is common in patients with HF. The relationship between AF and organ injury in HF remains unclear. We investigated the relationship between AF and the liver fibrosis marker, type IV collagen 7S (P4NP 7S) in patients with HF. Methods and resultsFrom a pooled dataset of 3 observational cohorts of hospitalized HF, 720 patients in whom P4NP 7S was measured before discharge were included. Median P4NP 7S were 5.1, 5.3, and 6.2 ng/mL in the sinus rhythm (SR) (n = 368), paroxysmal AF (n = 67), and persistent AF (n = 285) groups, respectively (P < 0.001). In the multiple linear regression analysis, the significant association with P4NP 7S was found for persistent AF (P < 0.001). The cumulative 1-year incidence of the primary composite endpoint of cardiac death and HF hospitalization were 27.6, 24.1, and 34.5% in the SR, paroxysmal AF, and persistent AF groups, respectively (Log-rank P = 0.07) and 25.3 and 34.5% in the low (below median) and high P4NP 7S groups, respectively (Log-rank P = 0.005). The adjusted risks of persistent AF versus SR and high P4NP 7S versus low P4NP 7S for the primary endpoint were 1.38 (95% confidence interval 1.02–1.89) and 1.52 (1.14–2.03), respectively. When patients were divided based on a combination of AF and P4NP 7S, concomitant persistent AF and high P4NP 7S portended a dismal prognosis. ConclusionAF is associated with an increase in the liver fibrosis marker. Co-presence of persistent AF and P4NP 7S may portend adverse clinical outcomes.

Clinical outcome of a single procedure cryoballoon ablation for the treatment of atrial fibrillation: A real-world multicenter experience in Portugal

BackgroundCryoballoon ablation (CBA) for pulmonary vein isolation (PVI) has been growing as an alternative technique, not only in patients with paroxysmal atrial fibrillation (PAF) but also in persistent atrial fibrillation (AF). Cryoballoon ablation has demonstrated encouraging acute and mid-term results. However, data on long-term follow-up of CB-based PVI are scarce. ObjectiveWe sought to examine efficacy, safety, and long-term outcomes of CBA in PAF and persistent AF in four Portuguese centers. MethodsAll patients that were treated with the cryoballoon catheter according to routine practices with a second-generation 28-mm CB in four centers were included. This was a retrospective, non-randomized analysis. Patients were followed-up for >12 months and freedom from atrial arrhythmias (AA) was evaluated at the end of follow-up. ResultsFour hundred and six patients (57.7±12.4 years, 66% men) participated. AF was paroxysmal in 326 patients (80.2%) and persistent in 80 (19.7%). The mean procedure time duration was 107.7±50.9 min, and the fluoroscopy time was 19.5±9.7 min. Procedural/periprocedural complications occurred in 30 cases (7.3%), being transient phrenic nerve palsy the most frequent incident (2 out of 3 complications). Anatomic variations of the PV were present in 16.1% of cases. At a mean follow-up of 22.0±15.0 months, 310 patients (76.3%) remained in stable sinus rhythm, with at least one AF episode recurrence documented in 98 cases (24.1%). The recurrence rate was 20.5% in the PAF group and 37.8% in the persistent AF group. ConclusionIn this multicenter experience, a single CBA procedure resulted in 75.9% freedom from AF at a 22-month follow-up. This technique was demonstrated to be a safe and effective option in experienced centers for the treatment of PAF and PersAF.

Atrial fibrillation recurrences despite durable pulmonary vein isolation: Characteristics, management and outcomes, the PARTY-PVI study

Recurrences of atrial fibrillation (AF) after pulmonary vein (PV) isolation (PVI) are mainly due to PV reconnections. However, a growing number of patients have recurrences despite durable PVI. The optimal ablative strategy for these patients is unknown. We aimed at analyzing the impact of various ablation strategies in such patients in the context of a large multicenter study. Patients scheduled for a redo ablation of AF and presenting durable PVI were included in 39 centers. PV-based, linear-based, electrogram-based and trigger-based ablation strategies were compared. A total of 367 patients underwent a redo AF ablation procedure revealing a durable PVI (43.6% paroxysmal AF, 67.0% men, 63.4 ± 10.2 years, CHA2DS2-VASc of 1.7 ± 1.4) between 2010 and 2020. Regarding strategy combinations, 200 (54.5%) patients underwent a single ablation strategy, while 136 (37.1%) and 24 (6.5%) patients underwent a combination of 2 and 3 strategies, respectively. Following the redo ablation procedure, arrhythmia recurrence was observed in 122 patients (33.2%) at 12 months. The recurrence rate was not significantly different between paroxysmal and persistent AF groups (P = 0.120). In multivariate analysis, none of the ablation strategies employed during the redo procedure improved the 12-month arrhythmia-free survival. The degree of left atrial dilatation (HR: 1.36, 95%CI: 1.13–1.65, P = 0.002) was the only independent factor associated with arrhythmia-free survival at 12 months (Fig. 1). In patients with recurrent AF despite durable PVI, no ablation strategy used during the redo procedure appears to be superior in improving the 12-month atrial arrhythmia free survival. The AF recurrence rate was the same whether the patient presented with a paroxysmal or persistent form of AF. Left atrial size is a major predictive factor of the arrhythmia-free survival in this population.

Biomarkers for Predicting the Occurrence and Progression of Atrial Fibrillation: Soluble Suppression of Tumorigenicity 2 Protein and Tissue Inhibitor of Matrix Metalloproteinase-1.

Soluble suppression of tumorigenicity 2 protein (sST2) and tissue inhibitor of matrix metalloproteinase (TIMP)-1 are involved in multiple pathogenic pathways, including cardiac remodeling, which is the main pathology of atrial fibrillation (AF). This study aims to investigate the previously unexplored relationship between the serum levels of sST2, TIMP-1, and AF. This was a prospective cross-sectional study conducted at the Capital Medical University Affiliated Beijing Anzhen Hospital between June 2019 and July 2020, with a total of 359 participants. The clinical characteristics and laboratory results of the patients were compared, and multivariable ordinal logistic regression was used to evaluate the relationship between serum sST2, TIMP-1, and AF. The participants included 110 patients with sinus rhythm (SR), 113 with paroxysmal AF (the paroxysmal AF group), and 136 with persistent AF (the persistent AF group). It was found that the sST2 levels gradually increased in these three groups, from 9.1 (6.7-12.4 pg/ml) in the SR group to 14.0 (10.4-20.8 pg/ml) in the paroxysmal AF group and to 19.0 (13.1-27.8) pg/ml) in the persistent AF group (p < 0.001). The multivariable ordinal logistic regression model for sST2 and TIMP-1 demonstrated that sST2 had an area under the receiver operating characteristic (ROC) curve (AUC) of 0.797 (95% confidence interval (CI) 0.749-0.846, p < 0.001) and TIMP-1 had an AUC of 0.795 (95% CI 0.750-0.841, p=0.000). The multivariable ordinal logistic regression model for sST2 and TIMP-1 showed good discrimination between SR and AF, with an AUC of 0.846, and the addition of clinical factors, such as brain natriuretic peptide (BNP), left atrial diameter, age, and gender, to the biomarker model improved the detection of SR and AF (AUC 0.901). In this cohort study, sST2 and TIMP-1 were associated with AF progression, independent of clinical characteristics and biomarkers. Soluble ST2 and TIMP-1 combined with age, elevated N-terminal-pro hormone BNP(NT-BNP), and an enlarged left atrium were able to demonstrate the progression of AF reliably.

High Internal Atrial Defibrillation Threshold Is Related to a High Risk of Recurrence After Catheter Ablation for Long-Standing Persistent Atrial Fibrillation But Not for Persistent Atrial Fibrillation.

The atrial defibrillation threshold (ADFT) for internal cardioversion is theoretically related to the critical mass for sustaining atrial fibrillation (AF). This study aimed to investigate the association of ADFT for internal cardioversion with the outcome of catheter ablation for non-paroxysmal AF (non-PAF). We included 368 consecutive patients who underwent first-time catheter ablation for non-PAF. Based on the degree of ADFT recorded by the internal cardioversion before pulmonary vein isolation, we divided the patients into low ADFT (<20 J) and high ADFT (≥20 J) groups and analysed the association between ADFT and atrial tachyarrhythmia recurrence. There were 234 and 134 patients in the low and high ADFT groups, respectively. Of these, 39 patients (16.7%) and 41 (30.6%) patients, respectively, had atrial tachyarrhythmia recurrence during the 2.6±1.0 year follow-up. The high ADFT group showed a significantly higher atrial tachyarrhythmia recurrence than the low ADFT group (p=0.002). This finding was also noted in patients with long-standing persistent AF (p=0.032) but not in patients with persistent AF (p=0.159). The significant predictors of arrhythmia recurrence on multivariate analysis were high ADFT (p=0.004) and long-standing persistent AF (p=0.011). In multivariate analysis within the long-standing persistent AF group, only ADFT remained a significant risk factor for AF recurrence (p=0.035). The high ADFT of internal cardioversion was found to be a risk factor for post-catheter ablation recurrence in patients with long-standing persistent AF but not in those with persistent AF.

Manganese Superoxide Dismutase as a Novel Oxidative Stress Biomarker for Predicting Paroxysmal Atrial Fibrillation.

Background: There is accumulating evidence indicating that inflammation and oxidative stress are involved in the pathogenesis of atrial fibrillation (AF). The role of manganese superoxide dismutase (MnSOD) in the initiation and maintenance of AF has not yet been well characterized. The aim of our study is to investigate whether or not plasma MnSOD levels are associated with AF. Methods: We enrolled a total of 130 consecutive patients with AF as the case group (paroxysmal AF: 87, persistent AF: 43) and 58 patients without a history of AF as the control group after screening. Baseline clinical characteristics, laboratory and echocardiographic parameters were collected. Plasma levels of nicotinamide-adenine dinucleotide phosphate oxidase 4 (NOX4) and MnSOD were measured by an enzyme-linked immunosorbent assay (ELISA) method. These data were compared between the different groups. The relationship between MnSOD and other parameters was assessed using Spearman correlation. Multivariable logistic regression analysis was performed to identify independent predictors of AF. The area under the curve (AUC) from receiver operating characteristics (ROC) analysis was constructed to explore the value of MnSOD in predicting the occurrence of AF. Results: The levels of MnSOD were the highest in the paroxysmal AF group, followed by the persistent AF group, and the lowest in the controls. Meanwhile, the levels in the paroxysmal AF group were significantly higher than those in the controls [322.84 (165.46, 547.61) vs. 201.83 (129.53, 301.93), p = 0.002], but no significant difference was found between the paroxysmal AF group and persistent AF group, as well as the persistent AF group and the controls. Spearman correlation analysis indicated that there was a significantly negative correlation between MnSOD levels and LAD (r = −0.232, p = 0.008) and a positive correlation between MnSOD levels and RDW-CV (r = 0.214, p = 0.014) in the case group. Multivariate logistic regression analysis indicated that MnSOD levels [odds ratio (OR): 1.003, 95% confidence interval (CI): 1.001–1.005, p = 0.002] were an independent risk factor for paroxysmal AF, and the best cut-off value of MnSOD in predicting paroxysmal AF gained by ROC curve analysis was 311.49 ug/mL (sensitivity of 52.9%, specificity of 77.6%, AUC = 0.668). Conclusion: Oxidative stress underlies the pathogenesis of AF and may play a stronger role in paroxysmal AF than persistent AF. Our study showed an independent association between increased circulating plasma MnSOD levels and the occurrence of paroxysmal AF.

A Single Center Experience of Atrial Fibrillation Ablation with Cryoballon

Background: Electrical isolation of the pulmonary veins is known as the fundamental of for atrial fibrillation (AF) treatment invasively, and thus, has been suggested as the first-line therapy in AF curation. In this study, we presented our single center pulmonary vein isolation (PVI) experience and long-term clinical outcome. &#x0D; Methods: One hundred and six symptomatic AF patients resistant to medical therapy underwent cryoablation of the pulmonary veins. Participants were divided into two groups regarding AF categorization as persistent or paroxysmal. Recurrence and peri-procedural complications were evaluated after the treatment.&#x0D; Results: A 106 patients, 67 males (63.2%), with mean age of 51.8 ±13.1 years, underwent cryoablation. While the paroxysmal AF group was composed of 90 patients (84.9%); the persistent AF group consisted of 16 patients (15.1%). The procedure mean time was 115,9±9,1 minute while the fluoroscopy mean time was 29,2±5,6 minutes. A total of 8 (7.5%) non-fatal complications were experienced. A total of 18 recurrences (17%) were observed during mean duration of 25.2 months follow-up period. The survival rates without AF were 85.6% and 61.8 % in in the paroxysmal and persistent groups, respectively.&#x0D; Conclusion: The cryoballoon PVI seems to be a successful and reliable method of treating AF and may be preferred as a primary procedure even in patients with persistent AF.

Effect of radiofrequency catheter ablation on left atrial structure and function in patients with different types of atrial fibrillation

Radiofrequency catheter ablation (RFCA) is widely used to treat atrial fibrillation (AF), but its effect on left atrial (LA) remodeling in patients with AF is not completely clarified. Few studies have reported the changes in structure and function of the left atrium in patients with different types of AF after RFCA. To analyze the effect of RFCA on the LA structure and function in patients with nonvalvular paroxysmal AF, persistent AF and long-standing persistent AF (LSPAF). RFCA was performed in 180 patients with paroxysmal AF, persistent AF and LSPAF. The changes of LA structure and function in echocardiogram and speckle-tracking echocardiography findings were compared before the procedure, and at 1, 2, 3, 4 weeks, and 2, 3, 6, and 9–12 months after the procedure. There were 60 patients in the paroxysmal AF group, 60 in the persistent AF group and 60 patients in LSPAF group. The pre-procedure LA diameter and volume were smaller in the paroxysmal AF group than persistent AF and LSPAF group. There was no significant change of in the LA structure and function in the paroxysmal AF group within 1 year. In the persistent AF and LSPAF groups, LA structure (anteroposterior diameter, LA volume) significantly decreased, but remained larger than that in paroxysmal AF group. In persistent and LSPAF, function (LA ejection fraction, strain, strain rate) increased significantly within 1 week, then gradually increased. RFCA improved the LA structure and function and resulted in heart reverse remodeling, especially for persistent AF and LSPAF.

Effect of a proactive esophageal cooling device on procedure length - a multicenter comparison of persistent and paroxysmal atrial fibrillation

Abstract Funding Acknowledgements Type of funding sources: None. Background During left atrial ablation for the treatment of atrial fibrillation (AF), effective esophageal protection is essential for reducing or preventing thermal injury. Traditional methods include luminal esophageal temperature (LET) monitoring that lead to frequent pauses in the procedure when temperature alarms alert operators to dangerous temperature levels. While there have been recent studies that demonstrate an association between active esophageal cooling and a reduction in procedure duration regardless of AF type, these retrospective studies have been conducted at single or joint centers which may lead to confounding from other time-saving variables that have changed over time. Purpose Consequently, we sought to perform a large-scale multicenter comparison to better elucidate the association between procedure length and the use of active cooling in patients with persistent and paroxysmal atrial fibrillation. Methods In this study, we collected data from three large hospital centers, one hospital-maintained registry, one physician-maintained registry, and one through EHR data review and aggregated in groups separated by AF type as well as whether the patients received active cooling or LET monitoring. We then compared median procedure durations in each group. Results There were a total of 753 patients included in this study. Of the 360 patients with paroxysmal AF, 179 received active esophageal cooling while 181 underwent LET monitoring. In the persistent AF group with 393 patients, 157 received active esophageal cooling and 236 underwent LET monitoring. Among patients with paroxysmal AF, the median mean procedure duration was 137 minutes in the LET monitored group, and 90 minutes in the actively cooled group with an overall reduction of 47 minutes (P&amp;lt;.001). In patients with persistent AF, the median procedure duration was 148 minutes in the LET monitored group and 94 minutes in the actively cooled group with an overall reduction of 54 minutes (P&amp;lt;.001). The relative reduction as a percent of total procedure time was 34%, and 36%, for paroxysmal and persistent AF cases, respectively. Conclusion In this large multicenter review, there is a significant reduction in procedure length when using active esophageal cooling, regardless of AF type.