B-PO02-140 EFFECT OF ATRIAL ECTOPY COUPLING INTERVAL ON ATRIAL STRUCTURAL REMODELLING AND ATRIAL FIBRILLATION IN A SWINE MODEL

Introduction: Atrial fibrillation (AF) is a major risk factor for cerebral ischemia in North America. Atrial ectopy has been associated with incident AF and increased stroke risk on short-duration ECG monitoring. The objective of this study was to characterize the relationship between the burden of atrial ectopy with future AF, stroke, and cardiovascular events on prolonged ECG monitoring. Methods: A retrospective, observational study was conducted at a single centre enrolling patients >18 years old referred from TIA clinic. Data was collected from 7- and 14-day Holter monitor reports, patient charts, and cardiac investigations. The final sample included 1124 patients; a subgroup of 759 patients had echocardiograms. Univariate and multivariate logistic regression determined the odds ratio (OR) of developing the composite outcome (AF, TIA/stroke, ACS, death) or secondary outcomes (AF or TIA/stroke). Results: The population was high-risk with a mean CHA 2 DS 2 -VASc of 4.0 (±1.8); during 1-year of follow-up, the primary outcome occurred amongst 116 (10.3%) patients. Univariate analysis ORs are displayed in Table 1. There was a statistically significant relationship (p<0.001) between percentage of PACs and the composite outcome (OR 4.066), and AF (11.886) for patients with 2-5% PACs. PAC runs/day was significant if >5/day for AF (OR 5.989, p<0.01) and for the composite (OR 2.231, p<0.05). Long PAC runs (>30 beats) also had significant ORs for AF (2.849, p<0.01) and the composite (5.320, p<0.01). In the subgroup analysis, reduced ejection fraction had an OR of 2.172 (1.407-5.771) for the composite outcome, and atrial dilatation had an OR of 2.778 (1.390-5.551) for AF. Conclusions: Increased burden of atrial ectopy is associated with increased odds of developing AF and a composite of cardiovascular events. Patients with increased ectopy should be considered for further, future ECG monitoring and risk stratification with echocardiogram.

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Excessive atrial ectopy and short atrial runs increase the risk of stroke beyond incident atrial fibrillation

Yearbook of Cardiology 2016 ◽

10.5005/jp/books/12834_84 ◽

2016 ◽

pp. 277-277

Author(s):

Dev Pahlajani

Keyword(s):

Atrial Fibrillation ◽

Atrial Ectopy

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Site-Specific Epicardium-to-Endocardium Dissociation of Electrical Activation in a Swine Model of Atrial Fibrillation

JACC: Clinical Electrophysiology ◽

10.1016/j.jacep.2020.04.015 ◽

2020 ◽

Vol 6 (7) ◽

pp. 830-845

Author(s):

Tomos E. Walters ◽

Geoffrey Lee ◽

Adam Lee ◽

Richard Sievers ◽

Jonathan M. Kalman ◽

...

Keyword(s):

Atrial Fibrillation ◽

Electrical Activation ◽

Swine Model ◽

Site Specific

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Interleukin-6-Mediated-Ca2+ Handling Abnormalities Contributes to Atrial Fibrillation in Sterile Pericarditis Rats

Frontiers in Immunology ◽

10.3389/fimmu.2021.758157 ◽

2021 ◽

Vol 12 ◽

Author(s):

Jie Liao ◽

Shaoshao Zhang ◽

Shuaitao Yang ◽

Yang Lu ◽

Kai Lu ◽

...

Keyword(s):

Atrial Fibrillation ◽

Ex Vivo ◽

Atrial Fibrosis ◽

Regional Heterogeneity ◽

Western Blots ◽

Talcum Powder ◽

Rat Hearts ◽

Arrhythmogenic Substrate ◽

Atrial Ectopy

Pre-existing Ca2+ handling abnormalities constitute the arrhythmogenic substrate in patients developing postoperative atrial fibrillation (POAF), a common complication after cardiac surgery. Postoperative interleukin (IL)-6 levels are associated with atrial fibrosis in several animal models of POAF, contributing to atrial arrhythmias. Here, we hypothesize that IL-6-mediated-Ca2+ handling abnormalities contribute to atrial fibrillation (AF) in sterile pericarditis (SP) rats, an animal model of POAF. SP was induced in rats by dusting atria with sterile talcum powder. Anti-rat-IL-6 antibody (16.7 μg/kg) was administered intraperitoneally at 30 min after the recovery of anesthesia. In vivo electrophysiology, ex vivo optical mapping, western blots, and immunohistochemistry were performed to elucidate mechanisms of AF susceptibility. IL-6 neutralization ameliorated atrial inflammation and fibrosis, as well as AF susceptibility in vivo and the frequency of atrial ectopy and AF with a reentrant pattern in SP rats ex vivo. IL-6 neutralization reversed the prolongation and regional heterogeneity of Ca2+ transient duration, relieved alternans, reduced the incidence of discordant alternans, and prevented the reduction and regional heterogeneity of the recovery ratio of Ca2+ transient. In agreement, western blots showed that IL-6 neutralization reversed the reduction in the expression of ryanodine receptor 2 (RyR2) and phosphorylated phospholamban. Acute IL-6 administration to isolated rat hearts recapitulated partial Ca2+ handling phenotype in SP rats. In addition, intraperitoneal IL-6 administration to rats increased AF susceptibility, independent of fibrosis. Our results reveal that IL-6-mediated-Ca2+ handling abnormalities in SP rats, especially RyR2-dysfunction, independent of IL-6-induced-fibrosis, early contribute to the development of POAF by increasing propensity for arrhythmogenic alternans.

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Concealed Pulmonary Vein Bigeminy during Sinus Rhythm in Patients with Paroxysmal Atrial Fibrillation: A Useful Marker for Pulmonary Vein Firing

Cardiology Research and Practice ◽

10.1155/2018/1834514 ◽

2018 ◽

Vol 2018 ◽

pp. 1-6

Author(s):

Jiqiang Hu ◽

Wu Kuang ◽

Xiaoyun Cui ◽

Yan Li ◽

Yang Wu ◽

...

Keyword(s):

Atrial Fibrillation ◽

Sinus Rhythm ◽

Success Rate ◽

Pulmonary Vein ◽

Recurrence Rate ◽

Paroxysmal Atrial Fibrillation ◽

Coupling Interval ◽

Ablation Success

Introduction. A concealed pulmonary vein (PV) bigeminy (cPVB) may be found in some patients with atrial fibrillation (AF) during sinus rhythm (SR). The aim of this study was to investigate whether the presence of cPVB during SR is associated with a higher PV firing. Methods and Results. Seven hundred seventy-six PVs (excluding 5 right middle PVs and 8 left common trunks) were mapped in 198 patients with paroxysmal AF (PAF) who underwent circumferential PV isolation. cPVB with a mean coupling interval of 136 ± 16 ms during SR was observed prior to ablation in 22 (11%) patients. Focal firing was provoked prior to ablation in 144 (19%) PVs. The incidence of focal firing was greater in PVs exhibiting cPVB compared with PVs without cPVB (89% vs. 16%; P<0.001). Also, the number of radiofrequency applications required for isolation was greater in ipsilateral PVs, exhibiting cPVB compared with ipsilateral PVs without cPVB (21.6 ± 6.8 vs. 18.2 ± 5.6; P=0.024). During a follow-up of 32 ± 20 months, the single ablation success rate was 82%. Compared with patients without cPVB, patients with cPVB were associated with higher recurrence rate of AF (27% vs. 17%; p=0.032). Conclusion. cPVB during SR was observed prior to index ablation in 11% of PAF patients. Such a potential itself may be a PV firing in a concealed manner, which does not reactivate LA. The PV exhibiting cPVB required a greater number of radiofrequency applications for isolation. Compared to patients without cPVB, the recurrence rate of AF in patients with cPVB was greater.

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ADDITION OF ATRIAL ECTOPY AND NT-PROBNP TO FRAMINGHAM ATRIAL FIBRILLATION RISK ALGORITHM IMPROVES RISK PREDICTION

Journal of the American College of Cardiology ◽

10.1016/s0735-1097(15)60470-3 ◽

2015 ◽

Vol 65 (10) ◽

pp. A470

Author(s):

Preman Kumarathurai ◽

Mette R. Mouridsen ◽

Nick Mattsson ◽

Bjorn Larsen ◽

Olav Nielsen ◽

...

Keyword(s):

Atrial Fibrillation ◽

Risk Prediction ◽

Risk Algorithm ◽

Atrial Ectopy

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Short coupling with high burden of atrial ectopy in twenty-four hour holter recording predicts recurrence of atrial arrhythmia after atrial fibrillation ablation

European Heart Journal ◽

10.1093/ehjci/ehaa946.0676 ◽

2020 ◽

Vol 41 (Supplement_2) ◽

Author(s):

T Okajima ◽

H Imai ◽

Y Murase ◽

N Kano ◽

Y Ogawa ◽

...

Keyword(s):

Atrial Fibrillation ◽

Catheter Ablation ◽

Atrial Arrhythmia ◽

Controlled Study ◽

Ablation Procedure ◽

High Burden ◽

Af Ablation ◽

Atrial Ectopy ◽

Holter Recordings

Abstract Background Atrial arrhythmia recurrence is experienced in up to 20% of patients after initially receiving a catheter ablation for atrial fibrillation (AF). Therefore, it is important to define predictors of atrial arrhythmia recurrence. Atrial ectopy (AE) with short coupling interval (S-AE) has been reported to be a trigger of AF. On the other hand, high burden of AE has been reported to be a useful predictor of atrial arrhythmia recurrences after AF ablation. Thus, the combination of the incidence of S-AE and AE burden during a 24-hour Holter recording could be a useful predictor of atrial arrhythmia recurrence after AF ablation. Purpose To investigate this hypothesis, we performed a retrospective case-controlled study. Methods We enrolled 180 patients who underwent their first catheter ablation procedure for AF and performed a 24-hour Holter recording between 90 to 365 days after their ablation procedure. Patients who performed an additional ablation procedure before the Holter recording were excluded. Finally, we analyzed 173 patients (age: 65±10 years, female: 28.3%, non-paroxysmal: 27.7%). The Holter recordings were analyzed by the same experienced technicians. We defined AE as a narrow QRS complex occurring >25% than prior R-R interval, and S-AE as AE occurring >55% earlier than expected. The relationship between the characteristics of AE during the Holter recording and atrial arrhythmia recurrences was investigated. Results The Holter recordings were performed at a median of 103 (IQR: 98–138) days after ablation. The median number of AE were 144 (IQR: 54–699) beats per day, and S-AE was recorded in 49 patients (28.3%). Forty-two patients (24.3%) had a recurrence of atrial arrhythmia during a median 488-day follow up period. Patients with S-AE had a recurrence of atrial arrhythmia more frequently than those without S-AE (44.9% vs 16.1%, p<0.001). We found the cut-off point of AE burden as 241 beats per day by the receiver operating characteristic curve with 74% sensitivity and 70% specificity to predict atrial arrhythmia recurrence. We divided the patients into four groups according to the presence or absence of S-AE and high AE burden. In the Kaplan-Meier analysis, patients with S-AE and high AE burden had the highest atrial arrhythmia recurrence rate (Log-rank test: p<0.001). In the Cox multivariate analysis, S-AE with high AE burden was an independent predictor of atrial arrhythmia recurrence (HR: 4.27, 95% CI: 2.32–7.85, p<0.001). Conclusion For AF patients who underwent their first catheter ablation, S-AE (>55% earlier than expected) with high AE burden (>241 beats per day) during the 24-hour Holter recording predicted recurrences of atrial arrhythmia. These results can help to develop follow-up strategies after AF ablation. Funding Acknowledgement Type of funding source: None

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