Interatrial Mechanical Dyssynchrony Worsened Atrial Mechanical Function in Sinus Node Disease With or Without Paroxysmal Atrial Fibrillation

Introduction: Atrial electromechanical dysfunction might contribute to the development of atrial fibrillation (AF) in patients with sinus node disease (SND). The aim of this study was to investigate the prevalence and impact of atrial mechanical dyssynchrony on atrial function in SND patients with or without paroxysmal AF. Methods: We performed echocardiographic examination with tissue Doppler imaging in 30 SND patients with (n = 11) or without (n = 19) paroxysmal AF who received dual‐chamber pacemakers. Tissue Doppler indexes included atrial contraction velocities (Va) and timing events (Ta) were measured at midleft atrial (LA) and right atrial (RA) wall. Intraatrial synchronicity was defined by the standard deviation and maximum time delay of Ta among 6 segments of LA (septal/lateral/inferior/anterior/posterior/anterospetal). Interatrial synchronicity was defined by time delay between Ta from RA and LA free wall. Results: There were no differences in age, P‐wave duration, left ventricular ejection fraction, LA volume, and ejection fraction between with or without AF. Patients with paroxysmal AF had lower mitral inflow A velocity (70 ± 19 vs 91 ± 17 cm/s, P = 0.005), LA active empting fraction (24 ± 14 vs 36 ± 13%, P = 0.027), mean Va of LA (2.6 ± 0.9 vs 3.4 ± 0.9 cm/s, P = 0.028), and greater interatrial synchronicity (33 ± 25 vs 12 ± 19 ms, P = 0.022) than those without AF. Furthermore, a lower mitral inflow A velocity (Odd ratio [OR]= 1.12, 95% Confidence interval [CI] 1.01–1.24, P = 0.025) and prolonged interatrial dyssynchrony (OR = 1.08, 95% CI 1.01–1.16, P = 0.020) were independent predictors for the presence of AF in SND patients. Conclusion: SND patients with paroxysmal AF had reduced regional and global active LA mechanical contraction and increased interatrial dyssychrony as compared with those without AF. These findings suggest that abnormal atrial electromechanical properties are associated with AF in SND patients.     

Effect of catheter ablation on progression of paroxysmal atrial fibrillation

Ablation and Progression of Atrial Fibrillation. Objective: The objective was to determine the effect of radiofrequency catheter ablation (RFA) on progression of paroxysmal atrial fibrillation (AF). Background: Progression to persistent AF may occur in up to 50% of patients with paroxysmal AF receiving pharmacological therapy. Hypertension, age, prior transient ischemic event, chronic obstructive pulmonary disease, and heart failure (HATCH score) have been identified as independent risk factors for progression of AF. Methods: RFA was performed in 504 patients (mean age: 58 ± 10 years) to eliminate paroxysmal AF. A repeat RFA procedure was performed in 193 patients (38%). Clinical variables predictive of outcome and their relation to progression of AF after RFA were assessed using multivariate analysis. Results: At a mean follow‐up of 27 ± 12 months after RFA, 434/504 patients (86%) were in sinus rhythm; 49/504 patients (9.5%) continued to have paroxysmal AF; and 14 (3%) were in atrial flutter. Among the 504 patients, 7 (1.5%) progressed to persistent AF. In patients with recurrent AF after RFA, paroxysmal AF progressed to persistent AF in 7/56 (13%, P < 0.001). The progression rate of AF was 0.6% per year after RFA (P < 0.001 compared to 9% per year reported in pharmacologically treated patients). Age >75 years, duration of AF >10 years and diabetes were independent predictors of progression to persistent AF. The HATCH score was not significantly different between patients with paroxysmal AF who did and did not progress to persistent AF (0.7 ± 0.8 vs 1.0 ± 0.5, P = 0.3). Conclusions: Compared to a historical control group of pharmacologically treated patients with paroxysmal AF, RFA appears to reduce the rate of progression of paroxysmal AF to persistent AF. Age, duration of AF, and diabetes are independent risk factors for progression to persistent AF after RFA. (J Cardiovasc Electrophysiol, Vol. 23, pp. 9‐14, January 2012)     

Efficacy of cardiac autonomic denervation for atrial fibrillation: a meta-analysis

Cardiac Autonomic Denervation and AF. Introduction : Adjunctive complex fractionated atrial electrograms (CFAE) ablation or ganglionated plexi (GP) ablation have been proposed as new strategies to increase the elimination of AF, but the difference between CFAE/GP ablation and pulmonary vein isolation (PVI), as well as the combined effect of CFAE/GP plus PVI ablation were unclear. This meta‐analysis was designed to determine whether adjunctive cardiac autonomic denervation (CAD) was effective for the elimination of AF, and whether CAD alone was superior to PVI in AF patients. Methods: A systemic literature search in MEDLINE, EMBASE, and Cochrane Controlled Trials Register (CCRT) was performed and controlled trials comparing the effect of PVI plus CFAE/GP ablation with PVI, as well as CFAE/GP ablation with PVI were collected. Results : A total of 15 trials including 1,147 patients with AF were qualified for this meta‐analysis. CAD plus PVI significantly increased the freedom from AF/ATs (OR 1.85, 95% CI: 1.33–2.59, P = 0.29). Subgroup analysis showed that additional CAD increased the ratio of sinus rhythm maintenance in both paroxysmal AF (OR 1.69; 95% CI: 1.09–2.62, P = 0.41) and nonparoxysmal AF (OR 2.11, 95% CI: 1.14–3.90, P = 0.14). Besides, when compared respectively, adjunctive CAD was not superior to PVI (OR 0.31; 95% CI: 0.11–0.86, P = 0.002). Conclusion : This study suggested that CAD plus PVI significantly increase the freedom from recurrence of AF both in paroxysmal and nonparoxysmal patients. However, when compared alone, the benefit of CAD was not superior to PVI. (J Cardiovasc Electrophysiol, Vol. 23, pp. 592–600, June 2012)     

Prevalence and predictors of complications of radiofrequency catheter ablation for atrial fibrillation

Complications of Atrial Fibrillation Ablation. Introduction: Up to 6% of patients experience complications after radiofrequency catheter ablation (RFA) of atrial fibrillation (AF). The purpose of this study is to determine the prevalence and predictors of periprocedural complications after RFA for AF. Methods and Results: The subjects were 1,295 consecutive patients (age = 60 ± 10 years) who underwent RFA (n = 1,642) for paroxysmal (53%) or persistent AF (47%) from January 2007 to January 2010. A complication occurred in 57 patients (3.5%); a vascular access complication in 31 (1.9%); pericardial tamponade in 20 (1.2%); a thromboembolic event in 4 (0.2%); deep venous thrombosis in 1 (<0.01%); and pulmonary vein stenosis in 1 patient (<0.01%). There were no procedure‐related deaths. On multivariate analysis, female gender (OR = 2.27; ±95% CI: 1.31–2.57, P < 0.01) and procedures performed in July or August (OR = 2.10; ±95% CI: 1.16–3.80, P = 0.01) were independent predictors of any complication. For vascular complications, treatment with clopidogrel (OR = 4.40; ±95% CI: 1.43–13.53, P = 0.01), female gender (OR = 3.65; ±95% CI: 1.72–7.75, P < 0.01) and performing RFA in July or August (OR = 2.71; ±95% CI: 1.25–5.87, P = 0.01) were independent predictors. The only predictor of cardiac tamponade was prior RFA (OR = 3.32; ±95% CI: 0.95–11.61; P < 0.05). Conclusion: Prevalence of perioperative complications for RFA of AF is 3.5% and vascular access complications constitute the majority. The need for clopidogrel therapy should be carefully considered prior to RFA. At teaching institutions close supervision should be exercised during vascular access early in the year. Improvements in ablation technology and elimination of the need for repeat procedures may decrease the risk of pericardial tamponade . (J Cardiovasc Electrophysiol, Vol. 22, pp. 626‐631, June 2011)     

Stroke event rates in anticoagulated patients with paroxysmal atrial fibrillation

Aims. To test the hypothesis that stroke and systemic embolic events (SEE) in the stroke prevention using an oral thrombin inhibitor in atrial fibrillation (SPORTIF) III and V trials are different between paroxysmal and persistent atrial fibrillation (AF). Methods. Data analysis from two cohorts of patients enroled in the prospective SPORTIF III and V clinical trials (n = 7329); 836 subjects (11.4%) with paroxysmal AF [mean age 70.1 years (SD = 9.5)] were compared with 6493 subjects with persistent AF for this ancillary study. Results. The annual event rates for stroke/SEE are 1.73% for persistent AF and 0.93% for paroxysmal AF. In a multivariate analysis, after adjusting for stroke risk factors, gender and aspirin usage, the differences remained statistically significant with a higher hazard ratio (HR) for stroke/SEE in persistent AF [vs. paroxysmal AF, HR 1.87, 95% confidence interval (CI) 1.04–3.36; P = 0.037]. In ‘high risk’ patients (with ≥2 stroke risk factors) annual event rates for stroke/SEE were 2.08% for persistent AF and 1.27% for paroxysmal AF (adjusted HR = 1.68, 95% CI 0.91–3.1, P = 0.098). Elderly patients had annual event rates for stroke/SEE of 2.38% for persistent AF and 1.13% for paroxysmal AF (adjusted HR = 2.27, 95% CI 0.92–5.59, P = 0.075). Vitamin K antagonist (VKA)‐naïve paroxysmal AF patients had a 1.89%/year stroke/SEE rate, compared with 0.61% for previous VKA takers (HR = 0.33, 95% CI 0.11–1.01, P = 0.052). Conclusion. In this large clinical trial cohort of anticoagulated AF patients, those with paroxysmal AF had stroke rates which were lower than for patients with persistent AF, although both groups had broadly similar stroke risk factors. Subjects with paroxysmal AF at ‘high risk’ had stroke/SEE rates that were not significantly different to persistent AF subjects.     

Incidence of asymptomatic cerebral microthromboembolism after atrial fibrillation ablation guided by complex fractionated atrial electrogram

Cerebral Microthromboembolism After CFAE Ablation . Background: The incidence of cerebral thromboembolism after pulmonary vein isolation (PVI) ranges from 2% to 14%. This study investigated the incidence of cerebral thromboembolism after complex fractionated atrial electrogram (CFAE) ablation with or without PVI. Methods: One hundred consecutive atrial fibrillation (AF) patients (50 paroxysmal and 50 persistent, including 10 longstanding) who underwent CFAE ablation combined with (n = 41, PVI+CFAE group) or without (n = 59, CFAE group) PVI were studied. Coronary angiography (CAG) was conducted with AF ablation in 5 cases in which coronary artery stenosis was suspected on 3D‐computed tomography. PVI was performed before CFAE ablation without circular catheter during AF. After termination of AF, additional ablation was performed to complete PVI with a circular catheter. All patients underwent cerebral magnetic resonance imaging (MRI) including diffusion‐weighted MRI and T2‐weighted MRI the day after ablation. Results: New thromboembolism was detected in 7.0%, and there was no significant difference between the 2 strategies (7.3% in PVI+CFAE group, 6.8% in CFAE group). CHADS2 score (1.6 ± 1.0 vs 0.8 ± 0.9, P < 0.05), left atrial volume (LAV; 83.8 ± 27.1 vs 67.8 ± 21.8, P < 0.05), and left ventricular ejection fraction (LVEF, 53.1 ± 9.2 vs 65.1 ± 9.7, P < 0.01) were significantly different when comparing patients with or without thromboembolism. In multivariate analysis, LVEF (odds ratio [OR], 0.92; 95% confidence interval [CI], 0.84–0.99; P < 0.05) and concomitant CAG (OR 18.82; 95% CI, 1.77–200.00; P < 0.05) were important predictors of new cerebral thromboembolism. Conclusions: The incidence of cerebral microthromboembolism after CFAE ablation was not greater than previous reports in PVI. Cautious management is required during AF ablation, especially in the patients with low LVEF. (J Cardiovasc Electrophysiol, Vol. 23, pp. 567–573, June 2012)     

Psychopathology and symptoms of atrial fibrillation: implications for therapy

Psychopathology and Symptoms of Atrial Fibrillation. Introduction: Current guidelines recommend that the choice of AF management strategy be guided by the symptomatic status of the patient when in AF. However, little is known regarding what drives AF symptoms. Several limited studies suggest that psychological distress may be linked with AF symptom severity. Methods: A total of 300 patients with documented AF completed a questionnaire assessing general health and well‐being, including a comprehensive psychological assessment as well as disease‐specific measures of AF symptom severity. AF burden was determined by 1‐week continuous looping monitor in a subset of patients. Analysis of covariance was used to determine the association between individual measures of depression, anxiety, and somatization disorder symptom severity with measures of general health status and AF‐specific symptom severity, adjusting for important confounders. Results: Patients with worsened severity of depression, anxiety, or somatization disorder symptoms had an associated increase in the severity of symptoms attributed to AF regardless of AF severity scale used (P < 0.0001 for each measure of psychological distress). This association persisted after adjusting for important confounders. Increasing severity of depression and anxiety symptoms were also associated with increased visits to medical care for AF management. Conclusions: Our study demonstrates the consequence of psychological distress on AF‐specific symptom severity and healthcare resource utilization. Psychological well‐being may strongly influence symptom severity and healthcare utilization. An assessment of psychological distress may be an important adjunct to standard AF management that warrants further study, particularly if symptom relief is the primary goal. (J Cardiovasc Electrophysiol, Vol. 23, pp. 473‐478, May 2012)     

Long-term outcome of catheter ablation in patients with atrial fibrillation originating from the superior vena cava

Long‐Term Outcome of SVC AF Ablation. Introduction: Data of the long‐term clinical outcome after superior vena cava (SVC) isolation are limited. We aimed to evaluate the long‐term outcome in patients with atrial fibrillation (AF) who had triggers originating from the SVC and received catheter ablation of AF. Methods and Results: The study consisted of 68 patients (age 56 ± 12 years old, 32 males) who underwent the ablation procedure for drug‐refractory, symptomatic paroxysmal AF originating from the SVC since 1999. Group 1 consisted of 37 patients with AF initiated from the SVC only, and group 2 consisted of 31 patients with both SVC and pulmonary vein (PV) triggers. During a follow‐up period of 88 ± 50 months, the AF recurrence rate was 35.3% after a single procedure. The freedom‐from‐AF rates were 85.3% at 1 year and 73.3% at 5 years. In the baseline study, group 2 had larger left atrium (38 ± 4 mm vs 36 ± 5 mm, P = 0.04), left ventricle (50 ± 5 mm vs 46 ± 5 mm, P = 0.003), and PV diameters. Kaplan–Meier survival analysis showed a higher AF recurrence rate in group 2 compared to that in group 1 (P = 0.012). The independent predictor of an AF recurrence was a larger SVC diameter (P = 0.02, HR 1.4, 95% CI 1.1–1.8). Conclusion: Among the patients with paroxysmal AF originating from the SVC, 73% remained free of AF for 5 years after a single catheter ablation procedure. Superior vena cava isolation without PV isolation is an acceptable therapeutic strategy in those patients with AF originating from the SVC only. The SVC diameter was an independent predictor of AF recurrence. (J Cardiovasc Electrophysiol, Vol. 23, pp. 955‐961, September 2012)     

心房颤动消融术中合并室上性心动过速的相关性研究

目的对心房颤动(房颤)消融术中合并阵发性室上性心动过速(室上速)的患者进行特征性分析。方法回顾性选取2016年1月至2018年6月浙江大学医学院附属邵逸夫医院庆春院区心内科所有接受房颤消融术的患者(1484例),依据术中是否合并室上速分为合并室上速组和未合并室上速组,分析性别、年龄、房颤类型是否与房颤消融术中合并室上速的关系。同时,以年龄50岁和65岁为界点,再次进行分层分析。术中合并室上速组患者明确机制后同时行慢径改良或旁路消融,进行长期随访。结果房颤消融术中合并室上速共41例(41/1484,2.76%)。其中,合并房室结折返性心动过速(AVNRT)29例,合并房室折返性心动过速(AVRT)12例。女性房颤组合并室上速(25/505)明显高于男性组(16/979,4.95%对1.63%,P<0.001);≤50岁房颤组合并室上速(8/133)的患者明显高于>50岁组(33/1351,6.02%对2.44%,P=0.016);阵发性房颤组合并室上速(29/741)的患者明显高于持续性房颤组(12/743,3.91%对62%,P=0.007)。Logistic回归分析显示女性、≤50岁、阵发性房颤是房颤消融术中合并室上速患者的高危因素(女性:OR=0.292,95%CI 0.151~0.565,P<0.050;≤50岁:OR=0.301,95%CI 0.131~0.689,P=0.004;阵发性房颤:OR=0.456,95%CI 0.230~0.906,P=0.025)。结论房颤消融术中患者应同时行电生理检查排除室上速,尤其是年龄较轻的女性阵发性房颤患者。     

Long‐Term Results of Transcatheter Atrial Fibrillation Ablation in Patients with Impaired Left Ventricular Systolic Function

AF Ablation and Impaired Left Ventricular Function. Introduction: Long‐term outcome of AF ablation in patients with impaired LVEF is unknown. The aim of this study is to evaluate sinus rhythm (SR) maintenance, clinical status, and echocardiographic parameters over a long‐term period following atrial fibrillation (AF) transcatheter ablation in patients with left ventricular ejection fraction (LVEF) <50%. Methods and Results: A total of 196 patients (87.2% males, age 60.5 ± 10.2 years) with LVEF <50% underwent radiofrequency transcatheter ablation for paroxysmal (22.4%) or persistent (77.6%) AF. Patients were followed up for 46.2 (16.4–63.5) months regarding AF recurrences, functional class, and echocardiographic parameters. All patients underwent pulmonary vein isolation, while 167 (85.2%) required additional atrial lesions. Eleven (5.6%) patients suffered procedural complications. During follow‐up, 58 (29.6%) patients required repeated ablations. At the follow‐up end, 15 (7.7%) patients died, while 74 (37.8%) documented at least one episode of AF, atrial flutter, or atrial ectopic tachycardia. Eighty‐three (47.2%) patients maintained antiarrhythmic drugs. During follow‐up, NYHA class improved by at least one class more frequently among patients maintaining SR compared to those experiencing relapses (70.6% vs 47.9%, P = 0.003). LVEF showed a broader relative increase in patients maintaining SR (32.7% vs 21.4%; P = 0.047) and mitral regurgitation grading significantly decreased (P <0.001) only within these patients. At multivariable analysis SR maintenance emerged as an independent predictor (odds ratio 4.26, 95% CI 1.69–10.74, P = 0.002) of long‐term clinical improvement (reduction in NYHA class ≥1 and relative increase in LVEF ≥10%). Conclusions: Although not substantially worse than in patients with preserved LVEF, AF ablation in patients with impaired LVEF is affected by high long‐term recurrence rate. Among these patients SR maintenance is associated with greater clinical improvement. (J Cardiovasc Electrophysiol, Vol. 24, pp. 24‐32, January 2013)     

Preprocedural predictors of atrial fibrillation recurrence following pulmonary vein antrum isolation in patients with paroxysmal atrial fibrillation: long-term follow-up results

Predictors of Recurrence after AF Ablation. Introduction: The objective of this study was to identify the simple preprocedural parameters of atrial fibrillation (AF) recurrence following single ablation procedure in patients with paroxysmal AF during long‐term follow‐up period. Methods and Results: Consecutive 474 patients (61 ± 10 years; 364 males, left atrial (LA) diameter 37.6 ± 5.1 mm) with drug‐refractory paroxysmal AF who underwent AF ablation were analyzed. Pulmonary vein antrum isolation (PVAI), cavotricuspid isthmus line creation with bidirectional conduction block, and elimination of all non‐PV triggers of AF were performed in all patients. With a mean follow‐up of 30 ± 13 months after single procedure, 318 patients (67.1%) were in sinus rhythm without any antiarrhythmic drugs. Multivariate analysis using Cox's proportional hazards model, including the age, gender, duration of AF, body mass index, LA size, left ventricular ejection fraction, and presence of hypertension and structural heart disease as variables, demonstrated that LA size was an independent predictor of AF recurrences after PVAI with a 7.2% increase in the probability for every 1 mm increase in LA diameter (P = 0.0007). When the patients were categorized into 3 groups according to the LA diameter, the patients with moderate (40–50 mm) and severe dilatation (>50 mm) had a 1.30‐fold (P = 0.0131) and 2.14‐fold (P = 0.0057) increase, respectively, in the probability of recurrent AF as compared with the patients with normal LA diameter (≤40 mm). Conclusion : In the long‐term follow‐up period, LA size was the best preprocedural predictor of AF recurrence following single ablation procedure in the patients with paroxysmal AF, even in the patients with a relatively small LA. (J Cardiovasc Electrophysiol, Vol. 22, pp. 621‐625, June 2011)     

Left atrial deformation imaging with ultrasound based two-dimensional speckle-tracking predicts the rate of recurrence of paroxysmal and persistent atrial fibrillation after successful ablation procedures

Predict AF. Objective: Since predictors of recurrence of atrial fibrillation (AF) after ablation procedures are poorly defined, this prospective study was conducted to assess the value of left atrial (LA) deformation imaging with two‐dimensional speckle‐tracking (2D‐ST) to predict AF recurrences after successful ablation procedures. Methods and results: One hundred and three consecutive patients (age 58.1 ± 16.6 years, 72.8% male) with AF (76 paroxysmal, 27 persistent) and 30 matched controls underwent transthoracic echocardiography and 2D‐ST‐LA‐deformation analysis with assessment of LA‐radial and LA‐longitudinal strain (Sr, Sl), and velocities derived from the apical 4‐ and 2‐chamber views (4CV, 2CV). AF recurrence was assessed during 6 months of follow‐up. For determination of AF‐related LA changes, AF patients were compared to controls and patients with AF recurrences after ablation procedures (n = 30, 29.1%) were compared with patients who maintained sinus rhythm (n = 73, 70.9%). Atrial deformation capabilities were significantly reduced (P < 0.0005) in patients with AF (4CVSl 17.8 ± 13.5%; 4CVSr 22.3 ± 14.9%; 4CV‐velocities 2.53 ± 0.97 seconds) when compared with controls (4CVSl 31.3 ± 12.4%; 4CVSr 30.3 ± 9.1%; 4CV‐velocities 3.48 ± 1.01 cm/s). Independent predictors for AF recurrence after ablation procedures were 2CV‐LA‐global‐strain (Sr, P = 0.03; Sl, P = 0.003), 4CV‐LA‐gobal‐strain (Sr, P = 0.03; Sl, P = 0.02), and regional LA‐septal wall‐Sl (P = 0.008). LA‐global‐strain parameters were superior to regional LA function analysis for the prediction of AF recurrences, with cutoff values (cov), hazard ratios (HR), positive and negative predictive values (PPV, NPV) were: 4CVSl cov, 10.79% (HR 27.8, P < 0.0005; PPV 78.8%, NPV 93.9%), 4CVSr cov, ?16.65% (HR 24.8, P < 0.0005; PPV 69.4%, NPV 96.6%), 2CVSl cov, 12.31% (HR 22.7, P < 0.0005; PPV 75.8%, NPV 95.3%), and 2CVSr cov, ?14.9% (HR 12.9, P < 0.0005; PPV 64.3%, NPV 93.2%). Conclusion: Compared with controls, AF itself seems to decrease LA deformation capabilities. The assessment of global LA strain with 2D‐ST identifies patients with high risk for AF recurrence after ablation procedures. This imaging technique may help to improve therapeutic guiding for patients with AF. (J Cardiovasc Electrophysiol, Vol. 23 p. 247‐255, March 2012.)     

Statin therapy for the prevention of atrial fibrillation trial (SToP AF trial)

Statins for Prevention of Atrial Fibrillation . Background: Inflammation and oxidative stress are associated with atrial fibrillation (AF). Statins have antioxidant and anti‐inflammatory properties. We tested if atorvastatin reduced AF recurrence after DC cardioversion (CV) by modifying systemic oxidative stress and inflammation (NCT00252967). Methods and Results: In a randomized, double‐blinded, placebo‐controlled trial, patients with atrial fibrillation/flutter (AF) were randomized to receive either atorvastatin 80 mg (n = 33) or placebo (n = 31) before CV. Treatment was continued for 12 months or until AF recurred. Serum oxidative stress markers (ratios of oxidized to reduced glutathione and cysteine, derivatives of reactive oxygen species, isoprostanes) and inflammatory markers (high‐sensitivity C‐ reactive protein [hs‐CRP], interleukin‐6 [IL‐6], interleukin‐1β[IL‐1β], tumor necrosis factor alpha [TNFα]) were measured at baseline and on follow‐up. AF recurred in 22 (66.7%) of atorvastatin and 26 (83.9%) of placebo group (P = 0.2). The adjusted hazard ratio of having recurrence on atorvastatin versus on placebo was 0.99 (95% CI: 0.98–1.01, P = 0.3). There was no significant difference in the time to recurrence using Kaplan–Meier survival estimates (median [IR]: 29 [2–145] days versus 22 [7–70] days, P = 0.9). Although no significant effect was seen on oxidative stress, 2 of 4 inflammatory markers, IL‐6 (adjusted OR: 0.59, 95% CI: 0.35–0.97, P = 0.04) and hs‐CRP (adjusted OR: 0.59, 95% CI: 0.37–0.95, P = 0.03) were significantly lowered with atorvastatin. Cholesterol levels significantly decreased with atorvastatin (P = 0.03). Conclusions: High‐dose atorvastatin did not reduce the recurrence of AF after CV. It reduced selective markers of inflammation without affecting systemic oxidative stress. Failure of atorvastatin to prevent AF recurrence may be due to its failure to affect oxidative stress. (J Cardiovasc Electrophysiol, Vol. 22, pp. 414‐419)     

Predictors of early recurrence and delayed cure after segmental pulmonary vein isolation for paroxysmal atrial fibrillation without structural heart disease

Background Early recurrence of atrial fibrillation (ERAF) and delayed cure are commonly observed after atrial fibrillation (AF) ablation. The purpose of this study was to determine the predictors of ERAF and delayed cure after a single pulmonary vein isolation (PVI) performed in paroxysmal AF patients without structural heart disease.Methods and results In 108 consecutive patients (93 men, 15 women; mean age 51 ± 8 years) with paroxysmal AF and no structural heart disease, segmental PVI guided by a Lasso catheter was performed. Forty-one percent (44/108) AF patients had ERAF after a single PVI. Univariate analysis revealed that left atrial diameter (p = 0.004), age (p = 0.024) and P-wave dispersion (p = 0.045) were significantly related to ERAF. Logistic regression analysis revealed that left atrial enlargement was the only independent predictor of ERAF (odds ratio [OR] 1.17; 95% confidence interval [CI] 1.04–1.30, p = 0.006). Delayed cure occurred in 32% (14/44) patients with ERAF. P-wave dispersion (p = 0.001), left atrial diameter (p = 0.008) were significantly related to delayed cure. P-wave dispersion was the only independent predictive factor of delayed cure (OR 0.91; 95% CI 0.85–0.97, p = 0.004).Conclusions Elderly patients with left atrial enlargement and a high dispersion of P wave are susceptible to ERAF after a single PVI. Left atrial enlargement is the only independent predictor of ERAF. Among patients with ERAF, those with less P-wave dispersion and less left atrial diameter have a higher probability of delayed cure. P-wave dispersion can independently predict delayed cure.This study was supported by National Natural Science Foundation of China. (NSFC No.30470704). There is not any potential conflict of interest.     

Catheter Ablation of Atrial Fibrillation in Patients With Valvular Heart Disease: Long‐Term Follow‐Up Results

AF Ablation in Patients With Valvular Heart Disease . Background: The purpose of this study is to evaluate the efficacy of atrial fibrillation (AF) ablation in patients with moderate valvular heart disease (VHD). Methods: In total, 534 consecutive patients who underwent AF ablation were enrolled. Patients with a history of valve surgery or other structural heart disease were excluded. Patients with clinically moderate VHD (group‐1, n = 45) were compared with those without VHD (control group‐2, n = 436). Ipsilateral pulmonary vein antrum isolation (PVAI) was performed with a double Lasso technique in all the patients. Left atrial (LA) linear ablation was undertaken in persistent AF patients, if AF was inducible after PVAI. Results: Patients in group‐1 were significantly older and had a larger LA. PVAI was successfully achieved in all the patients. Patients in group‐1 received LA linear ablation more frequently during the index procedure. After a median of 26 months from the index procedure, the freedom from AF was significantly lower in group‐1 than group‐2 off antiarrhythmic drugs (AADs) (47% vs 69%, P = 0.002). Although there were more number of total procedures in group‐1 than group‐2, the freedom from AF was lower at median 24 months after the last procedure (78% vs 87%, P = 0.038). There was no significant difference in the freedom from AF on AADs (91% vs 95%, P = 0.356) or complication rate between the 2 groups. Atrial tachycardia following the index procedure was observed more frequently in group‐1 (P = 0.001). Conclusion: The patients with VHD undergoing AF ablation are less likely to remain in sinus rhythm at long term without AADs than those without VHD. (J Cardiovasc Electrophysiol, Vol. 21, pp. 1193‐1198, November 2010)     

High-density mapping of atrial fibrillation in humans: relationship between high-frequency activation and electrogram fractionation

Introduction: Sites of complex fractionated atrial electrograms (CFAE) and dominant frequency (DF) have been implicated in maintaining atrial fibrillation (AF); however, their relationship is poorly understood. Methods and Results: Twenty patients underwent biatrial high‐density contact mapping (507 ± 150 points/patient) during AF. CFAE were characterized using software to quantify electrogram complexity (CFE‐mean). Spectral analysis determined the frequency with greatest power and sites of high DF with a frequency gradient. CFE‐mean was higher (less fractionated) for right compared with left atria (P < 0.001) and in paroxysmal compared with persistent AF (P < 0.001). DF was lower for right compared with left atria (P = 0.02) and in paroxysmal compared with persistent AF (P < 0.001). There was significant regional variation in DF in paroxysmal (P < 0.001) but not persistent AF. Highest DF points clustered together with 5.2 ± 1.7 clusters/patient. Correlation between CFE‐mean and DF was poor on a point‐by‐point basis (r =?0.17, P < 0.001), but moderate on an individual basis (r =?0.50, P = 0.03). Exploration of their spatial relationship demonstrated CFAE areas in close proximity (median 5 mm, IQR 2–10) to high DF sites; within 10 mm in 80% and 10–20 mm in 10%. Simultaneous activation mapping at these sites further supports this observation. Conclusion: Greater fractionation and higher DF are seen in persistent AF and left atria during AF. Preferential areas of high DF are observed in paroxysmal but not persistent AF. CFAE and DF correlate within an individual but not point‐by‐point. Exploration of their spatial relationship demonstrates CFAE in areas adjacent to high DF, and this is supported by activation mapping at these sites.     

Predictors of Atrial Fibrillation Recurrence After Radiofrequency Catheter Ablation: A Systematic Review

AF Recurrence After RFA: Systematic Review. Introduction: The relationship between success of radiofrequency ablation for atrial fibrillation (AF) and patient characteristics has not been systematically evaluated. Methods and Results: We searched MEDLINE and Cochrane Central Trials Registry databases from 2000 through 2008 for studies reporting preprocedure predictors and AF recurrence after radiofrequency ablation. We extracted multivariable analyses and univariable data on predictors and AF recurrence. Eligible studies were highly heterogeneous, particularly regarding ablation technique and definition of AF recurrence. Among 25 studies with multivariable analyses, two‐thirds to 90% of studies found that AF type, ejection fraction, left atrial diameter, structural heart disease, hypertension, and AF symptom duration did not predict AF recurrence (among patients with ejection fraction above 40% and left atrial diameter below about 55 mm). Studies found that gender and age were not predictors (in patients between 40 and 70 years old). Meta‐analyses of univariable AF recurrence rates by AF type in 31 studies found that studies were statistically heterogeneous, but that nonparoxysmal AF predicted AF recurrence compared to paroxysmal AF (relative risk 1.59; 95% confidence interval 1.38–1.82; P < 0.001); meta‐analyses of persistent or permanent versus paroxysmal AF yielded similar findings. Conclusion: Nonparoxysmal AF may be a clinically useful proxy for a combination of confounded variables, none of which alone is an independent predictor of AF recurrence. Evaluation of predictors was limited by exclusion of patients with severe heart disease or at the age extremes; thus, the evidence may not be as applicable to these populations. (J Cardiovasc Electrophysiol, Vol. 21, pp. 1208‐1216, November 2010)     

Long-term clinical efficacy and risk of catheter ablation for atrial fibrillation in the elderly

Introduction: The number of elderly patients with atrial fibrillation (AF) is increasing rapidly, and the safety and efficacy of catheter ablation in this demographic group has not been established. Methods: Over a 7‐year period we studied 1,165 consecutive patients undergoing 1,506 AF ablation procedures using a consistent ablation protocol that included proximal ostial pulmonary vein (PV) isolation and focal ablation of non‐PV AF triggers. Outcome was analyzed for three distinct age groups: <65 years (group 1; n = 948 patients), 65–74 years (group 2; n = 185 patients), and ≥75 years (group 3; n = 32 patients) based on the age at the initial procedure. Results: There was no significant difference in AF control (89% in group 1, 84% in group 2, and 86% in group 3, P = NS) during a mean follow‐up of 27 months. Major complication rates were also comparable (1.6% in group 1, 1.7% in group 2, 2.9% in group 3, P = NS) between the three groups. There was no difference in the left atrial size, percentage with left ventricular ejection fraction <50%, or percentage with paroxysmal versus more persistent forms of atrial fibrillation. However, older patients were more likely to be women (20% in group 1, 34% in group 2, and 56% in group 3, P < 0.001) and have hypertension and/or structural heart disease (56% in group 1 vs 68% in group 2 vs 88% in group 3; P < 0.001). There was a strong trend demonstrating that older patients were less likely to undergo repeat ablation (26% vs 27% vs 9%) to achieve AF control and more likely to remain on antiarrhythmic drugs (20% vs 29% vs 37%; P < 0.05). Conclusions: Elderly patients with AF undergoing catheter ablation therapy are represented by a higher proportion of women and have a higher incidence of hypertension/structural heart disease. To achieve a similar level of AF control, there appears to be no increased risk from the ablation procedure, but elderly patients are more likely to remain on antiarrhythmic drugs.     

Impact of Pharmacological Autonomic Blockade on Complex Fractionated Atrial Electrograms

Autonomic Blockade During Atrial Fibrillation . Introduction: The influence of the autonomic nervous system on the pathogenesis of complex fractionated atrial electrograms (CFAE) during atrial fibrillation (AF) is incompletely understood. This study evaluated the impact of pharmacological autonomic blockade on CFAE characteristics. Methods and Results: Autonomic blockade was achieved with propanolol and atropine in 29 patients during AF. Three‐dimensional maps of the fractionation degree were made before and after autonomic blockade using the Ensite Navx^® system. In 2 patients, AF terminated following autonomic blockade. In the remaining 27 patients, 20,113 electrogram samples of 5 seconds duration were collected randomly throughout the left atrium (10,054 at baseline and 10,059 after autonomic blockade). The impact of autonomic blockade on fractionation was assessed by blinded investigators and related to the type of AF and AF cycle length. Globally, CFAE as a proportion of all atrial electrogram samples were reduced after autonomic blockade: 61.6 ± 20.3% versus 57.9 ± 23.7%, P = 0.027. This was true/significant for paroxysmal AF (47 ± 23% vs 40 ± 22%, P = 0.003), but not for persistent AF (65 ± 22% vs 62 ± 25%, respectively, P = 0.166). Left atrial AF cycle length prolonged with autonomic blockade from 170 ± 33 ms to 180 ± 40 ms (P = 0.001). Fractionation decreases only in the 14 of 27 patients with a significant (>6 ms) prolongation of the AF cycle length (64 ± 20% vs 59 ± 24%, P = 0.027), whereas fractionation did not reduce when autonomic blockade did not affect the AF cycle length (58 ± 21% vs 56 ± 25%, P = 0.419). Conclusions: Pharmacological autonomic blockade reduces CFAE in paroxysmal AF, but not persistent AF. This effect appears to be mediated by prolongation of the AF cycle length. (J Cardiovasc Electrophysiol, Vol. pp. 766‐772, July 2010)     

Time to Cardioversion of Recurrent Atrial Arrhythmias After Catheter Ablation of Atrial Fibrillation and Long‐Term Clinical Outcome

Introduction: It is unclear whether early restoration of sinus rhythm in patients with persistent atrial arrhythmias after catheter ablation of atrial fibrillation (AF) facilitates reverse atrial remodeling and promotes long‐term maintenance of sinus rhythm. The purpose of this study was to determine the relationship between the time to restoration of sinus rhythm after a recurrence of an atrial arrhythmia and long‐term maintenance of sinus rhythm after radiofrequency catheter ablation of AF. Methods and Results: Radiofrequency catheter ablation was performed in 384 consecutive patients (age 60 ± 9 years) for paroxysmal (215 patients) or persistent AF (169 patients). Transthoracic cardioversion was performed in all 93 patients (24%) who presented with a persistent atrial arrhythmia: AF (n = 74) or atrial flutter (n = 19) at a mean of 51 ± 53 days from the recurrence of atrial arrhythmia and 88 ± 72 days from the ablation procedure. At a mean of 16 ± 10 months after the ablation procedure, 25 of 93 patients (27%) who underwent cardioversion were in sinus rhythm without antiarrhythmic therapy. Among the 46 patients who underwent cardioversion at ≤30 days after the recurrence, 23 (50%) were in sinus rhythm without antiarrhythmic therapy. On multivariate analysis of clinical variables, time to cardioversion within 30 days after the onset of atrial arrhythmia was the only independent predictor of maintenance of sinus rhythm in the absence of antiarrhythmic drug therapy after a single ablation procedure (OR 22.5; 95% CI 4.87–103.88, P < 0.001). Conclusion: Freedom from AF/flutter is achieved in approximately 50% of patients who undergo cardioversion within 30 days of a persistent atrial arrhythmia after catheter ablation of AF.