Efficacy of extended antrum ablation based on substrate mapping plus pulmonary vein isolation in the treatment of atrial fibrillation

Introduction and objectivesPulmonary vein isolation (PVI) technique has become the cornerstone of atrial fibrillation (AF) catheter ablation. The objective of this study was to assess the efficacy and safety of extended antrum ablation based on electrophysiological substrate mapping plus PVI in AF patients who underwent cryoballoon ablation.MethodsIn this observational study, a total of 121 paroxysmal AF patients and 80 persistent AF patients who did not achieve the procedure endpoint after cryoballoon ablation received extra extended antrum ablation (EAA) based on electrophysiological substrate mapping via radiofrequency ablation (EAA group). As a control group (PVI group), among paroxysmal AF and persistent AF patients, we conducted a propensity score-matched cohort, in whom only PVI was completed.ResultsThe average follow-up time was 15.27±7.34 months. Compared with PVI group, paroxysmal AF patients in the EAA group had a significantly higher rate of AF-free survival (90.1% vs. 80.2%, p=0.027) and AF, atrial flutter, or atrial tachycardia (AFLAT) -free rate survival (89.3% vs. 79.3%, p=0.031). Persistent AF patients in the EAA group also had a significantly higher rate of AF-free survival (90.0% vs. 75.0%, p=0.016) and AFLAT-free survival (88.8% vs. 75.0%, p=0.029) than PVI group. Complication rates did not significantly differ between both groups, in either paroxysmal AF or persistent AF patients.ConclusionOur findings demonstrate that extra extended antrum ablation based on electrophysiological substrate mapping is effective and safe. Moreover, the strategy can improve the outcome of AF cryoablation.     

Medium- and long-term outcome after a single second-generation cryoballoon ablation in patients with paroxysmal and persistent atrial fibrillation

Introduction and objectivesTo report medium- and long-term results following a single second-generation cryoballoon (CB2)-based ablation procedure in patients with paroxysmal (PAF) and persistent (PeAF) atrial fibrillation.MethodsA retrospective study was performed of consecutive patients undergoing a first CB2-based ablation procedure in a tertiary center. Cryoenergy was applied for 3 min if a time to effect <60 s was documented or 4 min otherwise, with a bonus application in cases of late isolation or suboptimal temperature. Follow-up was obtained from the regional health electronic records system and by telephone or personal interviews. Recurrence was defined as any atrial arrhythmia >30 s beyond a three-month blanking period. The clinical impact of recurrences was classified using a severity score.ResultsA total of 172 patients (134 PAF and 38 PeAF) were included, of whom 25 (14.5%) had structural heart disease and 120 (69.7%) had a normal or mildly dilated left atrium. Acute success was achieved in 167 (97.1%). After a median follow-up of 27 (14-41) months, 100 patients (58.1%) remained free of atrial arrhythmias (64.2% for PAF and 36.8% for PeAF, p=0.006). Left atrial size (p=0.05) and clinical presentation as PeAF (p=0.006) were predictors of recurrence. Of patients with recurrences, 11.1% did not require further therapies and an additional 16.7% had good control with antiarrhythmic drugs.ConclusionsA single CB2 procedure resulted in 58.1% of patients remaining free of atrial arrhythmias at 27-month follow-up. Conservative management was useful in 27.8% of patients with recurrences.     

Impact of catheter ablation for atrial fibrillation in patients with heart failure and left ventricular systolic dysfunction

Introduction and AimsCatheter ablation has been shown to improve left ventricular (LV) ejection fraction (LVEF) in patients with atrial fibrillation (AF) and heart failure (HF). Our aim was to assess the impact of AF ablation on the outcome of patients with HF and LV systolic dysfunction.MethodsWe performed a retrospective observational cohort study of all patients with HF and LVEF <50% and with no apparent cause for systolic dysfunction other than AF who underwent catheter ablation in a tertiary referral center between July 2016 and November 2018. The primary endpoint was a ≥5% improvement in LVEF. Secondary endpoints included improvement in New York Heart Association (NYHA) class and reduction in LV end-diastolic diameter (LVEDD) and left atrial diameter (LAD).ResultsOf 153 patients who underwent AF ablation in this period, 22 (77% male, median age 61 [IQR 54-64] years) fulfilled the inclusion criteria. Median follow-up was 11.1 months (IQR 6.1-19.0). After ablation, median LVEF increased from 40% (IQR 33-41) to 58% (IQR 55-62) (p<0.01), mean NYHA class improved from 2.35±0.49 to 1.3±0.47 (p<0.001), and median LAD and LVEDD decreased from 48.0 (IQR 43.5-51.5) mm to 44 (IQR 40-49) mm (p<0.01) and from 61.0 (IQR 54.0-64.8) mm to 55.0 (52.2-58.0) mm (p<0.01), respectively.ConclusionIn patients with HF and LV systolic dysfunction, AF ablation is associated not only with improved functional status but also with favorable structural remodeling, including improvement in LVEF and decreases in LAD and LVEDD.     

Clinical value of the combined use of P-wave dispersion and troponin values to predict atrial fibrillation recurrence in patients with paroxysmal atrial fibrillation

IntroductionP-wave dispersion (PWD) and cardiac troponin levels are independently associated with the recurrence of atrial fibrillation (AF) in patients with paroxysmal AF (PAF). We investigated the clinical usefulness of combining PWD and cardiac troponin I to predict AF recurrence in patients presenting to the emergency department with PAF.MethodsThis study included 65 patients with PAF who were divided into three groups according to baseline troponin I and PWD values (group 1, troponin I<0.11 ng/dl and PWD<44.5 ms; group II, troponin I<0.11 ng/dl and PWD≥44.5 ms, or troponin I≥0.11 ng/dl and PWD<44.5 ms; group III, troponin I≥0.11 ng/dl and PWD≥44.5 ms).ResultsThe AF recurrence rate was significantly higher in group III than in groups I and II. Multivariate analysis revealed that the troponin I and PWD values in group III (odds ratio: 7.236, 95% confidence interval: 1.879-27.861, p=0.004) were independent predictors of AF recurrence.ConclusionsThe combined use of PWD and basal troponin I levels is a better predictor of AF recurrence than either value alone.     

New-onset atrial fibrillation during acute coronary syndromes: Predictors and prognosis

IntroductionNew-onset atrial fibrillation (AF) frequently complicates myocardial infarction, with an incidence of 6–21%.ObjectiveTo assess the predictors and prognosis of new-onset AF during acute coronary syndromes (ACS).MethodsWe performed a retrospective observational cohort study including 902 consecutive patients (mean age 64 years, 77.5% male) admitted to a single center over a two-year period, with a six-month follow-up.ResultsAF rhythm was identified in 13.8% patients, of whom 73.3% presented new-onset AF and 26.8% pre-existing AF. New-onset AF was more frequent in older (p<0.001) and hypertensive patients (p=0.001) and in those with previous valvular heart disease (p<0.001) and coronary artery bypass grafting (p=0.049). During hospitalization, patients with new-onset AF more often had respiratory infection (p=0.002) and heart failure (p<0.001), and higher values of NT-proBNP (p=0.007) and peak creatinine (p=0.001). On echocardiography they had greater left atrial (LA) diameter (p<0.001) and more frequent significant mitral regurgitation (p<0.001) and left ventricular ejection fraction (LVEF) ≤40% (p<0.001) and were less likely to have significant coronary lesions (p=0.009) or to have undergone coronary revascularization (p<0.001). In multivariate analysis, age (OR 1.06, p=0.021), LVEF ≤40% (OR 4.91, p=0.002) and LA diameter (OR 1.14, p=0.008) remained independent predictors of new-onset AF. Together with age, diabetes and maximum Killip class, this arrhythmia was an independent predictor of overall mortality (OR 3.11, p=0.032).ConclusionsAge, LVEF ≤40% and LA diameter are independent predictors of new-onset AF during ACS. This arrhythmia is associated with higher overall mortality (in-hospital and in follow-up).     

Outcomes of radiofrequency catheter ablation for persistent and long-standing persistent atrial fibrillation

ObjectiveTo assess one-year outcomes in patients with persistent and long-standing persistent atrial fibrillation (AF) treated by catheter ablation.MethodsA retrospective observational study was conducted of consecutive patients referred for catheter ablation of persistent or long-standing persistent AF between May 2016 and October 2018. Patients underwent two different ablation strategies: pulmonary vein isolation (PVI) plus complex fractionated atrial electrograms (CFAE) (from May 2016 to June 2017) or a tailored approach (from July 2017 to October 2018). The overall recurrence rate at one year was analyzed. The secondary endpoint was arrhythmia recurrence according to the type of AF (persistent vs. long-standing persistent AF) and according to the ablation strategy employed.ResultsDuring the study period, 67 patients were included (40% with long-standing persistent AF). During a mean follow-up of 16±6 months, 27% of the patients had arrhythmia recurrence. Patients with long-standing persistent AF had a higher recurrence rate than those with persistent AF (44.4% vs. 15%, p=0.006), while patients who underwent a tailored approach presented better outcomes than those undergoing PVI plus CFAE ablation (17.5% vs. 40.7%, p=0.024). Ablation strategy (HR 6.457 [1.399-29.811], p=0.017), time in continuous AF (HR 1.191 [1.043-1.259], p=0.010) and left atrial volume index (HR 1.160 [1.054-1.276], p=0.002) were independent predictors of arrhythmia recurrence.ConclusionCatheter ablation is an effective treatment for patients with persistent and long-standing persistent AF. Patients with persistent AF and those undergoing a tailored approach presented lower arrhythmia recurrence.     

Prognostic difference between paroxysmal and non-paroxysmal atrial fibrillation in patients with hypertrophic cardiomyopathy

BackgroundThe association of atrial fibrillation (AF) with sudden death and the difference in prognostic significance between paroxysmal and non-paroxysmal AF remains unclear in patients with hypertrophic cardiomyopathy (HCM). Our aim was to investigate the clinical significance of AF, and to assess the prognostic difference between paroxysmal and non-paroxysmal AF in HCM patients.MethodsThe study included 430 HCM patients. Documentation of AF was based on electrocardiograms obtained either after the acute onset of symptoms or fortuitously during routine examination of asymptomatic patients.ResultsAF was detected in 120 patients (27.9%). In the patients with AF, syncope and non-sustained ventricular tachycardia were more frequent and the left atrial dimension was larger. Multivariate analysis showed that AF was an independent determinant of the outcome, including the risk of HCM-related death (adjusted hazard ratio 3.57, p < 0.001) and sudden death (adjusted hazard ratio 2.61, p = 0.038). When patients with AF were divided into subgroups with paroxysmal AF (n = 75) or non-paroxysmal AF (n = 45), only paroxysmal AF was identified as an independent determinant of the outcome, including the risk of HCM-related death (adjusted hazard ratio 5.24, p < 0.001) and sudden death (adjusted hazard ratio 4.67, p = 0.002).ConclusionsAF is a common supraventricular arrhythmia in HCM and has an adverse influence on the prognosis. In addition, each type of AF had a different clinical impact, with paroxysmal AF being a significant independent determinant of an adverse outcome, including sudden death.     

Cardiac resynchronization therapy in patients with atrial fibrillation: A meta-analysis

Background and ObjectiveTo combine the results of the best scientific evidence in order to compare the effects of cardiac resynchronization therapy (CRT) in heart failure patients with atrial fibrillation (AF) and in sinus rhythm (SR) and to determine the effect of atrioventricular nodal ablation in AF patients.MethodsThe electronic databases PubMed, B-On and Cochrane CENTRAL were searched, and manual searches were performed, for randomized controlled trials and cohort studies up to November 2012. The endpoints analyzed were all-cause and cardiovascular mortality and response to CRT.ResultsWe included 19 studies involving 5324 patients: 1399 in AF and 3925 in SR. All-cause mortality was more likely in patients with AF compared to patients in SR (OR=1.69; 95% CI: 1.20–2.37; p=0.002). There were no statistically significant differences in cardiovascular mortality (OR=1.36; 95% CI: 0.92–2.01; p=0.12). AF was associated with an increased likelihood of lack of response to CRT (OR=1.41; 95% CI: 1.15–1.73; p=0.001). Among subjects with AF, ablation of the atrioventricular node was associated with a reduction in all-cause mortality (OR=0.42; 95% CI: 0.22–0.80; p=0.008), cardiovascular death (OR=0.39; 95% CI: 0.20–0.75; p=0.005) and the number of non-responders to CRT (OR=0.30; 95% CI: 0.10–0.90; p=0.03).ConclusionsThe presence of AF is associated with increased likelihood of all-cause death and non-response to CRT, compared to patients in SR. However, many patients with AF benefit from CRT. Atrioventricular nodal ablation appears to increase the benefits of CRT in patients with AF.     

Edoxaban Treatment in routiNe clinical prActice in patients with non-valvular Atrial Fibrillation (ETNA-AF) in Iberia: Baseline data

Introduction and ObjectivesAtrial fibrillation (AF) is the most common form of arrhythmia worldwide and a significant health burden. Edoxaban, a recent novel oral anticoagulant (NOAC), is being investigated in the European real-world ETNA-AF study of patients with non-valvular atrial fibrillation (NVAF). The aim of this study was to characterize the Iberian edoxaban-treated cohort of ETNA-AF at baseline and to compare it with previously retrieved Portuguese data.MethodsPatients with NVAF treated with edoxaban and followed in Portuguese and Spanish centers were consecutively enrolled between June 2017 and January 2018. Only patients with a previous clinical decision to receive edoxaban were included. Patients’ baseline demographic and clinical parameters, medical history, and AF-related characteristics were retrieved.ResultsA total of 892 NVAF patients, with a mean age of 73.9 years, were included, 75.3% of whom received high-dose (60 mg) and 24.7% low-dose (30 mg) edoxaban. Most patients (55.9%) were male. Of the patients receiving 30 mg and 60 mg edoxaban, 55.9% and 37.9%, respectively, had an estimated CHA₂DS₂-VASc score ≥4. Previous bleeding event rates were low, with a predominance of clinically relevant non-major bleeding (1.9%). Most patients (47.5%) with NVAF had paroxysmal AF, followed by 26.4% with permanent AF. Median overall CHA₂DS₂-VASc score was 3.0 and median HAS-BLED score was 2.0. Previous treatments mostly included vitamin K antagonists (35.7%). A considerably higher proportion of patients on low-dose edoxaban required dose adjustments (71.4% vs. 8.6%). Overall adherence to label dosing recommendations was 86.5%.ConclusionsThis study provides valuable data on disease and patient profiles and will provide valuable insights into disease management and progression, as well as the safety, effectiveness, and patterns of cardiovascular events associated with edoxaban.     

Estudo Safira: reflexões sobre a prevalência e os padrões de tratamento de fibrilhação auricular e risco cardiovascular em 7500 indivíduos com 65 ou mais anos

Introduction and Aim

Atrial fibrillation (AF) is a common arrhythmia and an important risk factor for ischemic stroke. The current ESC guidelines state that all patients aged 65 and over should be regularly screened for AF. The SAFIRA study aimed to determine the prevalence, epidemiology and clinical and therapeutic characterization of AF in the Portuguese elderly population.

厄贝沙坦对高血压病并阵发性心房颤动患者左房功能的影响

目的观察厄贝沙坦对高血压病并阵发性心房颤动(简称房颤)患者左房功能的影响,探讨其对房颤预防及治疗的作用。方法104例高血压病合并阵发性房颤患者随机分治疗组和对照组。两组均给予基础降压治疗,治疗组除给予基础治疗外加用厄贝沙坦。3个月后通过超声心动图观察左房功能。结果治疗后两组左房各项指标均明显改善,其中左房上下径、左房最大容积改善程度治疗组较对照组大(32.47±7.38 mm vs 38.47±6.47 mm;18.45±3.67 mm vs 30.56±3.68 mm,P<0.05或0.01)。治疗组的房颤发生次数显著低于对照组(1.2±0.36次vs2.1±0.42次,P<0.01)。结论厄贝沙坦能改善高血压病并阵发性房颤患者左房功能,降低房颤发生次数。     

Evaluation of atrial function by 2D strain echocardiography in patients with atrial fibrillation

ObjectivesTo evaluate atrial function by 2D strain in patients with atrial fibrillation (AF) and normal or slightly increased atrial size and to verify whether lower atrial strain is associated with more frequent AF recurrences.Materials and methodsWe studied 50 patients with AF, mean age 59.6 ± 13 years and 50 age-and gender-matched controls. We analyzed left atrial function through 2Dstrain imaging, after the re-establishment of sinus rhythm (SR) and we investigated about the recurrences of the arrhythmia.ResultsAtrial strain (AS) was lower in AF patients vs controls (LA p<0.001; RA p<0.001). Lower AS was found in subjects with recurrent AF than in those with first episode of arrhythmia (LA4C p=0.01; LA2C p = 0.05; RA p=0.03).ConclusionsThe assessment of atrial function by strain imaging might help to identify patients who need more aggressive therapeutic strategies. Due to the small studied population and the short follow up period our data need to be confirmed by further and wider studies.     

Substrate and procedural predictors of outcomes after catheter ablation for atrial fibrillation in patients with hypertrophic cardiomyopathy

Background: Hypertrophic cardiomyopathy (HCM) is often accompanied by atrial fibrillation (AF) due to diastolic dysfunction, elevated left atrial pressure, and enlargement. Although catheter ablation for drug‐refractory AF is an effective treatment, the efficacy in HCM remains to be established. Methods: Thirty‐three consecutive patients (25 male, age 51 ± 11 years) with HCM underwent pulmonary vein (PV) isolation (n = 8) or wide area circumferential ablation with additional linear ablation (n = 25) for drug‐refractory AF. Twelve‐lead and 24‐hour ambulating ECGs, echocardiograms, event monitor strips, and SF 36 quality of life (QOL) surveys were obtained before ablation and for routine follow‐up. Results: Twenty‐one (64%) patients had paroxysmal AF and 12 (36%) had persistent/permanent AF for 6.2 ± 5.2 years. The average ejection fraction was 0.63 ± 0.12. The average left atrial volume index was 70 ± 24 mL/m 2 . Over a follow‐up of 1.5 ± 1.2 years, 1‐year survival with AF elimination was 62%(Confidence Interval [CI]: 66‐84) and with AF control was 75%(CI: 66‐84). AF control was less likely in patients with a persistent/chronic AF, larger left atrial volumes, and more advanced diastolic disease. Additional linear ablation may improve outcomes in patient with severe left atrial enlargement and more advanced diastolic dysfunction. Two patients had a periprocedureal TIA, one PV stenosis, and one died after mitral valve replacement from prosthetic valve thrombosis. QOL scores improved from baseline at 3 and 12 months. Conclusion: Outcomes after AF ablation in patients with HCM are favorable. Diastolic dysfunction, left atrial enlargement, and AF subtype influence outcomes. Future studies of rhythm management approaches in HCM patients are required to clarify the optimal clinical approach.     

Comparative study of atrial vulnerability in patients with unexplained ischemic stroke or lone atrial paroxysmal fibrillation

Strokes have a high prevalence, with a high rate of recurrence, and about 30-40% remain of unknown cause. Some patients might have asymptomatic paroxysmal atrial fibrillation (AF) which remains the main cause of embolic events. A latent atrial arrhythmogenic substrate may induce recurrent arrhythmias, including functional abnormalities such as nonuniform refractoriness and/or anatomic abnormalities such as atrial septum aneurysm (ASA) and patent foramen ovale (PFO). In 175 patients divided into three groups (Group I: 103 patients with unexplained ischemic stroke, Group II: 48 patients with paroxysmal AF and Group III or control group: 24 patients explored for another cause), such an atrial arrhythmogenic substrate was assessed by electrophysiological study. Groups I and II had a similar high rate of inducible atrial arrhythmias compared to control group III where no arrhythmia was induced. An induced atrial arrhythmia was observed in more than 50% of patients of Group I and in more than 70% of patients of Group II without any significant difference according to age. However, in 26 young patients of Group I who had a transesophageal echocardiography, both a high rate (46%) of ASA and/or PFO and a frequent latent atrial vulnerability (LAV) were observed, compared to older patients where an atrial septum abnormality was observed in only 21% of cases. Thus, among patients with stroke of unknown cause, a high percentage of them might have asymptomatic atrial paroxysmal arrhythmia. The predictive value of the electrophysiological study for spontaneous arrhythmias and recurrence of stroke remains to be demonstrated.     

三维超声心动图及斑点追踪成像评价左心房不同构型阵发性房颤患者左心房功能的临床研究

目的应用实时三维超声心动图(3D-RTE)及二维斑点追踪成像(2D-STI)评价左心房不同构型的阵发性房颤患者(PAF)左心房结构和功能。方法入选2017年1月至2018年12月于解放军总医院第七医学中心收治的阵发性房颤患者98例。根据二维超声左心房容积指数(LAVI-2D)将房颤患者分为左心房容积正常组(LAN组,LAVI<34 ml/m^2,50例)和左心房容积扩大组(LAE组,LAVI≥34 ml/m^2,48例)。选择同期38例临床资料匹配者为对照组。实时三维超声心动图测定左心房最大容积(LAVmax),左心房最小容积(LAVmin),左心房容积指数(LAVI-3D)和左心房总排空分数(LATEF)。斑点追踪显像获取左心房纵向时间-应变曲线,记录收缩期平均应变(SSL)和各时相平均应变率(mSRs、mSRe、mSRa)。结果PAF患者LAVI平均水平高于对照组,且LAE组LAVI水平高于LAN组,LAVI-3D测量值较LAVI-2D测量值高(P均<0.05)。PAF患者LATEF平均水平低于对照组,且LAE组LATEF水平小于LAN组(P均<0.05)。与对照组比较,PAF患者mSSL、mSRs、mSRe和mSRa水平均降低,LAE组mSSL、mSRs、mSRe和mSRa水平小于LAN组,差异有统计学意义(P均<0.05)。结论三维超声心动图较二维测量左心房容积大,能更准确评估左心房容积。左心房容积无明显增大房颤患者,已出现左心房功能减低。左心房扩大者应变指标进一步下降,左心房功能减低明显。三维超声心动图及斑点追踪成像能早期评价房颤患者左心房功能异常。     

Prevalence and outcomes of atrial fibrillation in a European healthcare area gained through the processing of a health information technology system

Introduction

Today's healthcare policies rely heavily on data that has been gathered from multiple small studies in intrinsically varied populations. We sought to describe the prevalence, comorbidities and outcomes of atrial fibrillation (AF) in the population of a specific region where all healthcare centers have implemented a common information technology (IT) structure.

热休克蛋白47在心房颤动患者心肌中的表达

目的探讨热休克蛋白47(HSP47)在心房颤动(简称房颤)患者心房结构重构中所起的作用。方法 60例行心脏手术的患者分为窦性心律组、阵发性房颤组、持续性房颤组,各组20例,于手术中获取右心耳心房组织,采用实时荧光定量方法检测HSP47的mRNA表达;同时采用超声心动图测量心房内径,并研究其相关性。结果与窦性心律组比较,阵发性房颤组及持续性房颤组中HSP47mRNA水平明显增加(P<0.05),且持续性房颤组较阵发性房颤组增加更明显(P<0.05)。房颤患者HSP47mRNA水平与左房内径呈显著正相关(r=0.780,P<0.01)。结论房颤患者心房组织中HSP47基因表达显著增加,并与房颤的严重程度密切相关。     

Relationships between paroxysmal atrial fibrillation,total oxidant status,and DNA damage

IntroductionStructural and electrophysiological changes play a critical role in the development of atrial fibrillation (AF). Although the pathophysiology of paroxysmal AF (PAF) has not been fully elucidated, oxidative stress (OS) and DNA damage appear to be important triggers. Thus far, no studies have investigated the relationships among total oxidant status (TOS), DNA damage, and PAF. The goal of this study was to assess TOS and DNA damage in patients with PAF.MethodsThis cross-sectional study included 56 patients with PAF and 31 healthy controls. OS was assessed based on TOS, total antioxidant capacity (TAC), and oxidative stress index (OSI). The level of DNA damage was assessed using 8-hydroxy-2′-deoxyguanosine (8-OHdG).ResultsThere were no significant differences between the groups in terms of baseline characteristics. However, patients with PAF had significantly higher high-sensitivity C-reactive protein (p=0.018), TOS (p=0.001), OSI (p=0.001), and 8-OHdG (p=0.019) levels, compared with the control group. Multivariate logistic regression analysis showed that serum TOS level (odds ratio: 1.608; 95% confidence interval [CI]: 1.188-2.176, p=0.002) was the only independent predictor of PAF. TOS ≥12.2 predicted PAF with a sensitivity of 82% and specificity of 76% (AUC: 0.785, 95% CI: 0.687-0.883, p<0.001).ConclusionWe found that TOS and DNA damage were significantly greater in patients with PAF than in the control group. Therefore, we propose that TOS and DNA damage can be used to detect patients at higher risk of AF.     

Reversal of pulmonary vein remodeling after catheter ablation of atrial fibrillation

Background Pulmonary veins (PV) and the atria undergo electrical and structural remodeling in atrial fibrillation (AF). This study aimed to determine PV and left atrial (LA) reverse remodeling after catheter ablation for AF assessed by chest computed tomography (CT). Methods PV electrophysiologic studies and catheter ablation were performed in 63 patients (68% male; mean ± SD age: 56 ± 10 years) with symptomatic AF (49% paroxysmal, 51% persistent). Chest CT was performed before and 3 months after catheter ablation. Results At baseline, patients with persistent AF had a greater LA volume (91 ± 29 cm³ vs. 66 ± 27 cm3; P = 0.003) and mean PV ostial area (241 ± 43 mm² vs. 212 ± 47 mm²; P = 0.03) than patients with paroxysmal AF. There was no significant correlation between the effective refractory period and the area of the left superior PV ostium. At 3 months of follow-up after ablation, 48 patients (76%) were AF free on or off antiar?rhythmic drugs. There was a significant reduction in LA volume (77 ± 31 cm³ to 70 ± 28 cm³; P < 0.001) and mean PV ostial area (224 ± 48 mm² to 182 ± 43 mm²; P < 0.001). Patients with persistent AF had more reduction in LA volume (11.8 ± 12.8 cm³ vs. 4.0 ± 11.2 cm³; P = 0.04) and PV ostial area (62 mm² vs. 34 mm²; P = 0.04) than those who have paroxysmal AF. The reduction of the averaged PV ostial area was significantly correlated with the reduction of LA volume (r = 0.38, P = 0.03). Conclusions Catheter ablation of AF improves structural remodeling of PV ostia and left atrium. This finding is more apparent in patients with persistent AF treated by catheter ablation.     

Correlation between genetic polymorphisms in apolipoprotein E and atrial fibrillation

This work explores correlations between genetic polymorphisms in apolipoprotein E (ApoE) and atrial fibrillation (AF). We detected polymorphisms in the APOE gene in 64 patients with AF and 49 non-AF volunteers at the Department of Cardiology of Lianyungang Second People's Hospital between July 2017 and July 2019. We found significant differences in age, body mass index, left atrial diameter, and left ventricular ejection fraction between the two groups. Six APOE genotypes were observed: ?2/?2; ?2/?3; ?2/?4; ?3/?3; ?3/?4; and ?4/?4. The ?3/?3 genotype was significantly less frequent in the AF group than in the control group, while the ?3/?4 and ?4/?4 genotypes were significantly more frequent in the AF group than in the control group (p<0.05). ApoE3 penetrance was significantly lower in the AF group than in the control group (p<0.05), while ApoE4 penetrance was significantly higher in the AF group than in the control group (p<0.05). ApoE3 penetrance was significantly lower in the AF group than in the control group (p<0.05). Binary logistic regression analysis showed that age, body mass index, left atrial diameter, left ventricular ejection fraction, and ApoE4 were risk factors for AF. Finally, we found that ApoE polymorphisms impacted the occurrence of AF and that ApoE4 is an AF-sensitive phenotype.