[Impact of CHA2DS2 VASc score on substrate for persistent atrial fibrillation and outcome post catheter ablation of atrial fibrillation].

OBJECTIVE: To explore if CHA2DS2 VASc score can predict substrate for persistent atrial fibrillation ( AF) and outcome post catheter ablation of AF. METHODS: From January 2011 to December 2012,116 patients underwent catheter ablation of persistent AF in our department and were enrolled in this study. CHA2DS2VASc score was calculated as follows: two points were assigned for a history of stroke or transient ischemic attack and age ≥ 75 and 1 point each was assigned for age ≥ 65, a history of hypertension, diabetes,recent cardiac failure, vessel disease, female. Left atrial geometry ( LA) was reconstructed with a 3.5 mm tip ablation catheter with fill-in threshold 10 in CARTO system. The mapping catheter was stabled at each endocardial location for at least 3 seconds for recording. The electrogram recordings at each endocardial location were analyzed with a custom software embedded in the CARTO mapping system. Interval confidence level (ICL) was used to characterize complex fractionated atrial electrograms (CFAEs) . As the default setting of the software, ICL more than or equal to 7 was considered sites with a highly repetitive CFAEs complex. CFAEs index was defined as the fraction of area of ICL more than or equal to 7 to the left atrial surface. The CFAEs index and outcome of catheter ablation among different CHA2DS2VASc groups were compared. RESULTS: Of the 116 patients, CHA2DS2VASc was 0 in 33 patients, 1 in 31 patients and ≥ 2 in 52 patients. Left atrial surface ((121.2 ± 18.9) cm2, (133.6 ± 23.8) cm2, (133.9 ± 16.1) cm2, P = 0.008), left atrial volume ((103.6 ± 24.8) ml, (118.3 ± 27.8) ml, (120.9 ± 20.9) ml, P = 0.005) and CFAEs index (44.6% ± 22.4%, 54.2% ± 22.2%, 58.7% ± 23.1%, P = 0.023) increased in proportion with increasing CHA2DS2VASc. ICLmax, ICLmin and CFAEs spatial distribution were similar among the three groups. During the mean follow-up of (13 ± 8) months, the recurrence rate were 36.4%, 35.5%, 55.8% among the three groups (P = 0.025). CONCLUSION: A high CHA2DS2VASc score is associated with extensive AF substrate and higher recurrence rate post catheter ablation of persistent AF.

Oral anti-coagulants use in Chinese hospitalized patients with atrial fibrillation / 中华医学杂志(英文版)

BACKGROUND@#Oral anti-coagulants (OAC) are the intervention for the prevention of stroke, which consistently improve clinical outcomes and survival among patients with atrial fibrillation (AF). The main purpose of this study is to identify problems in OAC utilization among hospitalized patients with AF in China.@*METHODS@#Using data from the Improving Care for Cardiovascular Disease in China-Atrial Fibrillation (CCC-AF) registry, guideline-recommended OAC use in eligible patients was assessed.@*RESULTS@#A total of 52,530 patients with non-valvular AF were enrolled from February 2015 to December 2019, of whom 38,203 were at a high risk of stroke, 9717 were at a moderate risk, and 4610 were at a low risk. On admission, only 20.0% (6075/30,420) of patients with a diagnosed AF and a high risk of stroke were taking OAC. The use of pre-hospital OAC on admission was associated with a lower risk of new-onset ischemic stroke/transient ischemic attack among the diagnosed AF population (adjusted odds ratio: 0.54, 95% confidence interval: 0.43-0.68; P  <0.001). At discharge, the prescription rate of OAC was 45.2% (16,757/37,087) in eligible patients with high stroke risk and 60.7% (2778/4578) in eligible patients with low stroke risk. OAC utilization in patients with high stroke risk on admission or at discharge both increased largely over time (all P  <0.001). Multivariate analysis showed that OAC utilization at discharge was positively associated with in-hospital rhythm control strategies, including catheter ablation (adjusted odds ratio [OR] 11.63, 95% confidence interval [CI] 10.04-13.47; P <0.001), electronic cardioversion (adjusted OR 2.41, 95% CI 1.65-3.51; P <0.001), and anti-arrhythmic drug use (adjusted OR 1.45, 95% CI 1.38-1.53; P <0.001).@*CONCLUSIONS@#In hospitals participated in the CCC-AF project, >70% of AF patients were at a high risk of stroke. Although poor performance on guideline-recommended OAC use was found in this study, over time the CCC-AF project has made progress in stroke prevention in the Chinese AF population.Registration:ClinicalTrials.gov, NCT02309398.

Correlation Between Mitral Annular Calcification and Recurrence of Atrial Fibrillation After Radiofrequency Ablation / 中国循环杂志

Objectives:To explore the correlation between mitral annulus calcification(MAC)and recurrence of atrial fibrillation(AF)after radiofrequency ablation. Methods:The study included 785 patients with AF who underwent radiofrequency ablation in Beijing Anzhen Hospital from January 1,2019 to December 31,2020.According to the recurrence of AF after operation,patients were divided into recurrence group and non-recurrence group.Univariate Cox regression model was used to analyze the risk factors associated with AF recurrence,and multivariate Cox regression model was used to evaluate the influence of MAC on AF recurrence. Results:The average follow-up was(16±10)months.190 patients(24.2%)in the recurrence group,595(75.8%)patients in the non-recurrence.Patients in the recurrence group were older,had a higher proportion non-paroxysmal AF,a higher proportion of MAC,moderate/severe mitral regurgitation and larger left atrial diameter(LAD),and higher CHA2DS2-VASc score(all P<0.001).Univariate analysis showed that MAC was a risk factor of AF recurrence after radiofrequency ablation(HR=2.530,95%CI:1.639-3.907,P<0.001).After adjusting for age and sex,MAC remained significantly associated with an increased risk of AF recurrence after radiofrequency ablation(HR=1.52,95%CI:1.14-2.17,P<0.001).After multivariate adjustment for age,sex,non-paroxysmal AF,hypertension,diabetes,LAD,moderate/severe mitral regurgitation,and CHA2DS2-VASc score,MAC remained as an independent risk factor of AF recurrence(HR=1.48,95%CI:1.13-1.95,P=0.001). Conclusions:MAC is significantly associated with an increased risk of AF recurrence after radiofrequency ablation.

ABC-AF-Stroke score predicts thromboembolism in non-anticoagulated patients following successful atrial fibrillation ablation: a report from the Chinese Atrial Fibrillation Registry / 中华医学杂志(英文版)

BACKGROUND@#The age, biomarkers, and clinical history (ABC)-atrial fibrillation (AF)-Stroke score have been proposed to refine stroke risk stratification, beyond what clinical risk scores such as the CHA2DS2-VASc score can offer. This study aimed to identify risk factors associated with thromboembolism and evaluate the performance of the ABC-AF-Stroke score in predicting thromboembolism in non-anticoagulated AF patients following successful ablations.@*METHODS@#A total of 2692 patients who underwent successful ablations with discontinued anticoagulation after a 3-month blanking period in the Chinese Atrial Fibrillation Registry (CAFR) between 2013 and 2019 were included. Cox regression analysis was conducted to present the association of risk factors with thromboembolism risk. The ABC-AF-Stroke score was evaluated in terms of discrimination, including concordance index (C-index), net reclassification improvement (NRI) and integrated discrimination improvement (IDI), clinical utilization by decision curve analysis (DCA), and calibration by comparing the predicted risk with the observed annualized event rate.@*RESULTS@#After a median follow-up of 3.5 years, 64 patients experienced thromboembolism events. Age, prior history of stroke/transient ischemic attack (TIA), high-sensitivity cardiac troponin T (cTnT-hs), and N-terminal pro-B-type natriuretic peptide (NT-proBNP) were independently associated with thromboembolism risk. The ABC-AF-Stroke score performed statistically significantly better than the CHA2DS2-VASc score in terms of C-index (0.67, 95% confidence interval [CI]: 0.59-0.74 vs. 0.60, 95% CI: 0.52-0.67, P = 0.030) and reclassification capacity. The DCA implied that the ABC-AF-Stroke score could identify more thromboembolism events without increasing the false positive rate compared to the CHA2DS2-VASc score. The calibration curve showed that the ABC-AF-Stroke score was well calibrated in this population.@*CONCLUSIONS@#In this real-world study enrolling non-anticoagulated AF patients following successful ablations, age, prior history of stroke/TIA, level of NT-proBNP, and cTnT-hs were independently associated with an increased risk of thromboembolism. The ABC-AF-Stroke score was well-calibrated and statistically significantly outperformed the CHA2DS2-VASc score in predicting thromboembolism risk.

The impact of digoxin on the long-term outcomes in patients with coronary artery disease and atrial fibrillation / 中华内科杂志

Objective:To investigate the long-term safety of digoxin in patients with coronary artery disease (CAD) and atrial fibrillation (AF).Methods:This was a prospective study, in which 25 512 AF patients were enrolled from China Atrial Fibrillation Registry Study. After exclusion of patients receiving ablation therapy at the enrollment, 1 810 CAD patients [age: (71.5±9.3)years] with AF were included. The subjects were grouped into the digoxin group and non-digoxin group, and were followed up for a period of 80 months. Long-term outcomes were compared between the groups and an adjusted Cox regression analysis was applied to evaluate the risk of digoxin on the long-term outcomes. The primary endpoint was all-cause mortality.Results:The patients were followed up for a median period of 3.05 years. After multivariable adjustment, the Cox regression analysis showed that digoxin significantly increased the risk of all-cause mortality ( HR=1.28, 95% CI 1.01-1.61, P=0.038), cardiovascular mortality ( HR=1.48,95% CI 1.10-2.00, P=0.010), cardiovascular hospitalization ( HR=1.67,95% CI 1.35-2.07, P=0.008) and the composite endpoints ( HR=2.02,95% CI 1.71-2.38, P<0.001). In the subgroup of patients with heart failure (HF), digoxin was not associated with the risk of all-cause mortality, but was still associated with the increased risk of cardiovascular mortality ( HR=1.44,95% CI 1.05-1.98, P=0.025), cardiovascular hospitalization ( HR=1.44,95% CI 1.09-1.90, P=0.010) and the composite endpoints ( HR=1.37, 95% CI 1.01-1.70, P=0.004). However, in the subgroup of patients without HF, digoxin was only associated with all-cause mortality ( HR=2.56,95% CI 1.44-4.54, P=0.001). Conclusion:Digoxin significantly increased the risk of all-cause mortality in CAD patients with AF, especially in patients without HF.

Association between weight control and recurrence of atrial fibrillation after catheter ablation in overweight and obese patients / 中华心血管病杂志

Objectives@#This study explored the relationship between weight control and atrial fibrillation (AF) recurrence after catheter ablation in overweight and obese patients.@*Methods@#We prospectively enrolled consecutive 333 overweight and obese patients aged 28 to 87 years old, who underwent catheter ablation for AF in Beijing Anzhen Hospital between October 2015 and February 2016. Data of patients′ characteristics, laboratory examination and treatment were collected at baseline. Each patient was followed up at 3, 6 and 12 months after ablation to collect information on weight, AF recurrence, stroke, major bleeding, hospitalization for cardiovascular reasons and death, etc. Patients were divided into weight controlled group (ΔBMI<-1 kg/m2) and weight uncontrolled group (ΔBMI≥-1 kg/m2), according to the changes in the most recent exposure BMI before AF recurrence in patients with recurrence or the BMI at 12 months′ follow-up in patients without recurrence and the BMI at baseline. Multivariate logistic regression was performed to adjust other known risk factors of AF recurrence and to explore the association between weight control and AF recurrence after catheter ablation.@*Results@#There were 54 patients in weight controlled group and 279 patients in weight uncontrolled group. There were no significant differences in age, gender, education level, left atrial size and history of hypertension between the two groups (all P>0.05). The proportion of patients using angiotensin-converting enzyme inhibitors/angiotensin receptor blockers was higher in the weight controlled group (50.0%(27/54) vs. 34.8%(97/279), P=0.034). However, there was no significant difference in the proportion of patients with obesity (33.3% (18/54) vs. 29.7% (83/279)), paroxysmal AF (59.3% (32/54) vs. 56.6% (158/279)) and AF duration less than 5 years (76.9% (40/52) vs. 65.4% (178/272)) between the weight controlled group and the uncontrolled group. During 1-year follow-up after ablation, the recurrence rate of AF was significantly lower in the weight controlled group than that in the weight uncontrolled group (14.8% (8/54) vs. 32.6%(91/279), P=0.009). Multivariable logistic regression analysis shows that weight control is independently associated with a lower postoperative AF recurrence rate (OR=0.40, 95%CI 0.18-0.90, P=0.026).@*Conclusion@#Weight control is strongly associated with a lower AF recurrence rate after catheter ablation in overweight and obese patients.

Changes in renal function after catheter ablation in patients with persistent atrial fibrillation / 中华内科杂志

Objective@#The aim of the study was to evaluate the changes and outcome of kidney function after catheter ablation in patients with persistent atrial fibrillation (PAF).@*Methods@#A total of 146 patients with PAF underwent primary atrial fibrillation (AF) ablation were enrolled from January 2013 to December 2014 and followed up. The subjects were divided into the AF recurrence and AF non recurrence groups. The estimated glomerular filtration rate (eGFR) was calculated and serum creatinine levels were detected before ablation and during follow-up. Renal failure was defined as ≥ 25% decline in eGFR. Kaplan-Meier survival curves was applied for the incidence of renal failure. Cox proportional hazards models were conducted to assess the relationship between recurrence of AF and renal failure.@*Results@#After (16.3±11.8) months of follow-up, the eGFR in patients with no recurrence of AF was higher than that in patients with recurrence. eGFR and ΔeGFR in patients with no AF recurrence differed significantly from those in patients with recurrence [(114.15±18.24) ml·min-1·1.73m-2 vs. (98.64±24.09) ml·min-1·1.73m-2, and (7.42±6.36) ml·min-1·1.73m-2 vs. (-11.40±10.19) ml·min-1·1.73m-2, all P<0.001]. The incidence of the renal failure was significantly lower (4.41% vs. 16.67%, P<0.05) and the survival prognosis was significantly better in patients with no recurrence than those in patients with recurrence (χ2=5.965, log-rank P=0.05). The multivariate Cox regression analysis revealed that age, baseline eGFR, recurrences of AF and diabetes were independent predictors of the renal failure, with the HR 1.152, 1.086, 13.442 and 6.076, respectively.@*Conclusions@#PAF patients with no recurrence after ablation had a better renal function than those with recurrence, and the recurrence of AF is associated with the deterioration of kidney function in patients with PAF.

Association between herpes simplex virus infection and atrial fibrillation in elderly individuals / 中华老年医学杂志

Objective To investigate associations of herpes simplex virus(HSV)infection with elevated high-sensitivity C-reactive protein(hsCRP)level and the development of atrial fibrillation(AF) in elderly individuals.Methods Through screening a total of 2,603 individuals,49 patients aged 60 years or over with AF and without structural heart diseases and known risk factors for AF were selected for data collection.Fifty-five elderly healthy control subjects were selected from a population based Chinese Arrhythmia Registry.Baseline characteristics,plasma antibody levels against HSV-1 and-2,and level of hsCRP were analyzed.Results Level of antibodies against HSV-1 was significantly higher in AF patients[(314.5±63.6)mg/L than in control subjects(216.0±50.7) mg/L,P＜0.01].Level of antibodies against HSV-2 was significantly higher in AF patients[(400.1±50.7) mg/L than in control subjects (306.3 ± 64.5) mg/L,P ＜ 0.01].Linear regression analysis demonstrated a positive correlation of plasma levels of hsCRP with both anti-HSV-1 and anti-HSV-2 IgG antibodies (r =0.291,0.188,all P ＜ 0.01).In multiple logistic regression analysis,HSV-1 and HSV-2 antibody levels were significantly associated with AF occurrence(OR =1.035 and 1.034,all P ＜0.01).The optimal cut-off point for predicting AF occurrence was 284.96 mg/L for anti-HSV-1 with sensitivity of 67.3％ and a specificity of 92.7％,and was 366.26 mg/L for anti-HSV-2 with a sensitivity of 67.3％ and a specificity of 85.5％,respectively.Conclusions The increased plasma levels of anti-HSV-1 and anti-HSV-2 antibodies are significantly associated with AF occurrence in elderly adults.

Different strategies for the ablation of atrial tachycardia in the redo ablation of persistent atrial fibrillation / 中国介入心脏病学杂志

Objective The recurrence of perimitral atrial tachycardia is common after initial ablation of persistent atrial fibrillation (AF). The aim of the study is to explore a preferable ablation approach for perimitral atrial tachycardia in the redo ablation of persistent AF. Methods Seventy-four patients with perimitral atrial tachycardia after initial ablation for persistent AF were included in our study. Patients were distinguished into either the group of having ablation during tachycardia (Group A) or the group having ablation after cardioversion to sinus rhythm (Group B) according to the different ablation strategies. The procedural endpoints were pulmonary vein isolation and bidirectional conduction block of all the ablated lines. The primary endpoint of the study was freedom from atrial tachyarrhythmia recurrence during the follow-up period. Results There were statistical differences in baseline clinical data between the 2 groups. During the redo procedure, conduction recovery rate across the mitral isthmus (MI),cavotricuspid isthmus and left atial roofline were 100％, 40.5％ and 48.6％ respectively. The procedural time, fluoroscopy time, mapping time were longer in the patients of group A. During a mean follow-up of (16.9±6.3) months, 31 (72.1％) patients in group A and 21(67.7％) patients in group B maintained in sinus rhythm in the absence of antiarrhythmic durgs (P =0.771) . Conclusion In patients with perimitral atrial tachycardia after initial ablation for persistent AF,ablation in sinus rhythm is a more simplified method and as effective as ablation during tachycardia.

Three-dimensional ultrasound guided catheter ablation of premature ventricular components originating from left anterior ventricular papillary muscles via transspetal puncture / 中国介入心脏病学杂志

Objective To investigate ablation characteristics of PVC/VT originating from left ventricle anterior papillary muscles.Methods This study included 10 patients of PVC/VT originating from left ventricle anterior papillary muscles from January 2015 to June 2016 in Beijing Anzhen Hospital.Electrophysiological mapping and radiofrequency ablation were completed using three-dimensional anatomical mapping system combined with three-dimensional intracardiac ultrasound technology.ECG and abaltion target diagram characteristics as well as the special anatomy were explored.Results All the 10 patients were successfully ablated and followed up for 12 months.One patient had recurrence within 12 months and no complications were recorded.The target sites localized at the tip (n =1),middle portion(n =4)or the base (n =5) of the LV-APM.Among 7 patients,the target sites were located at the anterior septal papillary muscle and in 3 patients were located in the free papillary muscle.9 patients were successfully ablated via anterograde trans-septal catheterization after the failure of retrograde approach.Premature QRS wave time were 152.80 ± 11.72 ms and 6 patients presented sharp potential at the targets during PVC/VT.Conclusions PVC/VT originating from left ventricle anterior papillary muscles have similar ECG and diagram characteristics that is different from which originating from left anterior fascicle.It is recommended to get the target via transseptalpuncure approach.Ablation target could be clearly positioned by three-dimensional intracardiac ultrasound technology.

Prophylactic atropine administration prevents vasovagal response induced by cryoballoon ablation in patients with atrial fibrillation / 中国介入心脏病学杂志

Objective Cryoballoon ablation of pulmonary vein (PV) ostia often induces a vagal response.This prospective study was designed to assess the effectiveness of prophylactic intravenous administration of atropine on hemodynamic impairment induced by cryoballoon ablation in patients with atrial fibrillation.Methods Twenty-five patients with paroxysmal atrial fibrillation undergoing cryoballoon ablation were prospectively enrolled and assigned to either the trial group on the control group.First twelve patients (the trial group) were administered 1 mg of atropine before deflation of the cryoballoon,while the following 13 patients (the control group) were given atropine only after the onset of the hemodynamic variation (decrease in heart rate and/or blood pressure).Treatment was considered effective when the hemodynamic variations were restored.Results In the trial group,three patients with transient hypotension did not require further supportive care throughout the procedures and one patient with hypotension required supportive management.In the control group,hypotension,bradycardia and mixed bradycardia with hypotension requiring supportive care occurred in six,three,and three patients,respectively.Overall,the rate of marked vagal responses was significantly lower when prophylactic atropine was administrated (4/12 vs.12/13 patients,P ＜ 0.01).Conclusions Atropine is effective in the prevention of all types of vasovagal responses induced by cryoballoon ablation in patients with atrial fibrillation.

Predictors of atrial fibrillation recurrence after catheter ablation in hypertrophic cardiomyopathy patients with atrial fibrillation / 中华心血管病杂志

<p><b>OBJECTIVE</b>To evaluate the efficacy of catheter ablation in Chinese hypertrophic cardiomyopathy (HCM) patients with atrial fibrillation (AF), and to determine the risk factors of AF recurrence.</p><p><b>METHODS</b>This study enrolled 40 HCM patients with AF who underwent primary AF ablation at Beijing Anzhen Hospital from June 2005 to June 2013. Ablation strategy included bilateral pulmonary vein isolation (PVI) for paroxysmal AF (n = 27) and PVI plus left atrial roof, mitral isthmus and tricuspid isthmus linear ablations for persistent AF (n = 13). AF recurrence was followed-up by means of electrocardiography or Holter monitoring. Risk factors associated with AF recurrence were determined by a Cox regression model and the predictive power was evaluated by receiver operating characteristic (ROC) curve.</p><p><b>RESULTS</b>After (34 ± 18) months follow-up, 30% (12/40) cases remained in sinus rhythm off antiarrhythmic drug, most AF recurrence (18/28, 64.3%) occurred within 1 year post ablation. Multivariate Cox regression demonstrated that left atrial dimension (LAD, HR = 1.124, 95% CI 1.051-1.202, P = 0.001) and female gender (HR = 3.304, 95% CI 1.397-7.817, P = 0.007) were independent risk factors of AF recurrence. The cut-off value of LAD at 43.5 mm predicted AF recurrence with sensitivity of 93.5% and specificity of 60.0%. Every 1 mm enlargement in LAD was associated with an increased risk of arrhythmia recurrence (HR = 1.095, 95% CI 1.031-1.163, P = 0.003).</p><p><b>CONCLUSIONS</b>AF ablation in Chinese HCM patients is safe and feasible. However, sinus rhythm maintenance rate is low at long-time follow-up. Most of the recurrent AF occurs within 1 year post AF ablation procedure. Left atrial diameter and female gender are independent risk factors of AF recurrence.</p>

Long-term results of single-procedure catheter ablation for atrial fibrillationin pre-and post-menopausal women / 老年心脏病学杂志（英文版）

Objectives To address whether menopause affects outcome of catheter ablation (CA) for atrial fibrillation (AF) by comparing the safety and long-term outcome of a single-procedure in pre-and post-menopausal women. Methods A total of 743 female patients who underwent a single CA procedure of drug-refractory AF were retrospectively analyzed. The differences in clinical presentation and outcomes of CA for AF between the pre-menopausal women (PreM group, 94 patients, 12.7%) and the post-menopausal women (PostM group, 649 patients, 87.3%) were assessed. Results The patients in the PreM group were younger (P<0.001) and less likely to have hypertension (P<0.001) and diabetes (P=0.005) than those in the PostM group. The two groups were similar with regards to the proportion of concomitant mitral valve regurgitation coronary artery disease, left atrium dimensions, and left ventricular ejection fraction. The overall rate of complica-tions related to AF ablation was similar in both groups (P=0.385). After 43 (16-108) months of follow-up, the success rate of ablation was 54.3%in the PreM group and 54.2%in the PostM group (P=0.842). The overall freedom from atrial tachyarrhythmia recurrence was simi-lar in both groups. Menopause was not found to be an independent predictive factor of the recurrence of atrial tachyarrhythmia. Conclusions The long-term outcomes of single-procedure CA for AF are similar in pre-and post-menopausal women. Results indicated that CA of AF appears to be as safe and effective in pre-menopausal women as in post-menopausal women.

Electrophysiological characteristics and cause analysis of ridge related reentry after catheter ablation of atrial fibrillation / 中国介入心脏病学杂志

Objective To identify the electrophysiological charateristics and cause of ridge gap related reentry after MI ablation in atrial ifbrillation patients. Methods Activation and entrainment mapping was performed in 82 redo cases for OAT recurrence in whom MI was ablated during the index produre. Once ridge gap related reentry was conifrmed, detailed mapping was performed in MI and ridge region. In addition, in 36 cases undergoing MI ablation and fulfilling criterion for bidirectional block, differential pacing was repeated at the ridge to identify a ridge gap. Results Out of 82 redo cases for OAT recurrence in whom MI was ablated during the index produre, 7 (8.5%) was found to be ridge gap related reentry. TCL was (247.9±19.2) ms, and the left atrial endocardial activation time was (145.4±17.7) ms, accounting for (58.5±3.2)%of TCL. However, wide double potential was recorded along the previous ablated MI line where PPI was (34.3±6.6) ms longer than TCL, while PPI was signiifcantly shorter at the ridge[PPI-TCL (11.4±3.9) ms, P<0.001]. Tachycardia was terminated at the ridge in 6 cases and at the corresponding site in coronary sinus in 1 case. No recurrence was found during follow-up for (11.1±4.5) months. In addition, in 36 patients undergoing MI ablation in whom criterion of bi-directional block was fuliflled, conduction gap located at the ridge was found in 5 (13.9%) cases. Conclusions MI ridge gap related reentry is a distinctive OAT, in which the ridge was used as the critical isthmus, whereas the previous ablated MI line is not part of the reentry. MI pseudo-block due to the ridge gap may lead to this type of recurrent tachycardia.

Characteristics of induced atrial arrhythmias and long-term follow-up after pulmonary vein isolation in ;patients with paroxysmal atrial ifbrillation / 中国介入心脏病学杂志

Objective Identify the mechanism of induced atrial arrhythmias after pulmonary vein isolation (PVI) in patients with paroxysmal atrial ifbrillation(PAF), and investigate its long-term prognosis. Methods All patients with PAF undergoing PVI and induction test afterwards between Feburary 2010 and October 2010 were included. The induction protocol was rapid pacing initiated at cycle length of 250 ms with progressive shortening in a decrement of 10 ms down to 180 ms or refractoriness. Isoproterenol of 2-4μg/min was administrated as well. Inducibility was deifned as induction of atrial arrhythmia lasting >1 min. The mechanism of induced tachycardia was identiifed by activation mapping and entrainment mapping under the guidance of CARTO system. All patients were followed up by 36 months. Results Forty-nine atrial tachycardia were induced in 39 (19.7%) patients, including 35 organized atrial tachycardia (OAT) and 14 atrial ifbrillation (AF). The LA diameter was signiifcantly larger in inducible group than non-inducible group (39.5±6.6 mm vs. 36.7±5.2 mm, P=0.004). Macroreentry was the most common mechanism in induced OATs (28, 80.0%), and mitral isthmus was the most common critical site (20, 40.8%), followed by cavo-tricuspid isthmus (12, 24.5%), PV (6, 12.2%), LA septum (4, 8.2%), superior vena cava (3, 6.1%) and LA roof (1, 2.0%). Conclusions The most common mechanism of induced tachycardia by IV isoproterenol and rapid pacing is MI and CTI dependent after PVI in PAF patients, which can be succssefully eliminated by liner ablation, not increasing long-term recurrence rate.

The management of cardiac tamponade complications during catheter ablation of atrial ifbrillation ;using different periprocedure anticoagulation strategies / 中国介入心脏病学杂志

Objective To observe the management and outcome of the cardiac tamponade patients during the ablation procedure using two different anticoagulation strategies. Methods All the patients developed tamponade during the ablation procedure were enrolled from January 2007 to December 2013 in our center. In group 1, warfarin was discontinued 3 to 5 days before the procedure and low molecular weight heparin (LMWH) was administered subcutaneously until ablation procedure day. In group 2, warfarin was not discontinued and the international normalized ratio INR was to maintained between 2 and 3. Results There were 27 patients (0.6%) developed cardiac tamponade out of a total 4487 patients received ablation in our center. The baseline clinical characteristics including age, left atrium, the heparin dose and ACT during the procedure had no signiifcant difference between the groups, except that the INR was higher in the group 2 (0.9±0.1 vs. 2.3±0.5, P0.999). The median hospital day was similar in the 2 groups [(9.6±3.3) d vs. (12.1±4.5) d, P=0.167]. There were no other serious complications and no hospital death. Conclusions Non-discontinuation of warfarin during peri-procedural catheter ablation of AF is not signiifcantly different to bridging with LMWH in the management and outcome of acute cardiac tamponade.

Clinical efficacy and safety of catheter ablation for atrial fibrillation in elderly patients / 中华老年医学杂志

Objective To evaluate the clinical efficacy and safety of catheter ablation for atrial fibrillation in elderly patients.Methods From September 2008 to October 2011,a total of 420 consecutive patients undergoing catheter ablation of atrial fibrillation (AF) were selected.The patients were divided into 3 age groups:30 59 yr group (n=279),60-74 yr group (n=100),and 75-87 yr group (n =41).The effect of operation and complications during operative and postoperative periods were evaluated.Patients were followed up for at least 6 months,and the rate of atrial fibrillation reocurrence and life quality were recorded.Results Among 480 catheter ablation procedures,in 7 (1.5％) patients occurred main complications,while in 5 (1.0％) patients appeared other complications.The incidence of main complications in 3 groups were 1.1％ (3 patients),2.0％ (2 patients) and 4.9％ (2 patients) respectively,other complication rates in 3 groups were 0.7％ (2 patients),1.0％ (1 patient) and 4.9％ (2 patients) respectively and there were no differences between groups (all P＞0.05).During follow-up,the cases without AF relapse were 68.5％ (191 patients),66.0％ (66 patients) and 57.1％ (23 patients) respectively,and the patients with AF paroxysm were 21.1％ (59 patients),21.0％ (21 patients),29.3％ (12 patients) respectively,and there was no significant difference between groups (all P＞0.05).And no difference was found in improvement degree of life quality among three groups (P＞0.05).Conclusions Catheter ablation is safe and effective in elderly patients.For patients over 75 years with many types of cardiovascular diseases,catheter ablation is effective to control the relapse of AF,can significantly improve the quality of life,and has no increased risk of complications.

CT image integration into three-dimensional electroanatomical mapping system on guidance for catheter ablation of atrial fibrillation / 中国组织工程研究

BACKGROUND:Circumferential pulmonary vein antrum ablations guided by CARTO system or integration of a computed tomographic or magnetic resonance imaging scan (CARTO-Merge) are two main locating methods.Theoretically,CARTO-Merge provides a detailed appreciation of the pulmonary vein anatomy,however,whether it can improve the safety and success of catheter ablation of atrial fibrillation remains uncertainly.OBJECTIVE:To explore the effect of CT image integration into three-dimensional (3D) electroanatomical mapping system on clinical outcomes of catheter ablation of atrial fibrillation.DESIGN,TIME AND SETTING:The randomized contrast observation was performed at Department of Cardiology of Beijing Anzhen Hospital from October 2005 to May 2007.PARTICIPANTS:A total of 93 patients with drugs refractory,paroxysmal atrial fibrillation who underwent circumferential pulmonary vein antrum ablation.METHODS:All patients underwent circumferential pulmonary vein antrum ablation using irdgated radiofreguency ablation with the endpoint of electrical isolation.Ablation was guided by 3D mapping alone in 50 patients (CARTO group) or by CT image integration in 43 patients (CARTO-Merge group).MAIN OUTCOME MEASURES:Procedure-related parameters,such as procedure duration,fluoroscopy duration,cumulative success rate and complication,were compared between the two groups.RESULTS:Pulmonary veins were isolated in all patients.After (12.6±2.9) months follow-up,73 (78.5%) patients did not have recurrence of atrial fibrillation at 3 month after the procedure.The fluoroscopy time in CARTO group was significant longer than that in CARTO-Merge group (P<0.05).The mean procedure duration,radiofrequency ablation duration,procedure-related complication and cumulative success rate were comparable between the 2 groups.CONCLUSION:Circumferential pulmonary vein antrum ablation guided by 3D mapping alone or by CT integration had similar safety and success rate in paroxysmal atrial fibrillation patients.But CT integration,which facilitated to a detailed representation of the anatomy of left atrium,is associated with reduced fluoroscopy duration.

Safety and efficacy of circumferential pulmonary vein linear ablation guided by 3-D mapping system in patients with atrial fibrillation / 中国实用内科杂志

Objective To investigate the safety and efficacy of circumferential pulmonary vein linear ablation guided by 3-D mapping system in patients with atrial fibrillation.Methods From April 2003 to March 2006,410 consecutive patients with atrial fibrillation underwent circumferential pulmonary vein linear ablation guided by 3-D mapping system(CARTO system or EnSite NavX TM system).Success was defined as symptomatic atrial tachyarrhythmia free after 3 months washout period.Results 96%of the 410 patients attained the ablation endpoint.After a mean of (12.4?6.8)months' follow-up,clinical success achieved in 77.3% of the patients with paroxysmal atrial fibrillation and 69.4% of the patients with persistent/permanent atrial fibrillation after first-time ablation procedure.The successs rate of the persistent/permanent atrial fibrillation was significantly lower than that of paroxysmal atrial fibrillation.Forty-one of the 103 patients with recurrent atrial fibrillation underwent ablation again.Thirty-one of the 41 patients(75.6%)were atrial tachyarrhythmia free during the follow-up.Severe complications included 4 cases of pericardial tamponade(0.97%)and 3 cases of stroke(0.73%).Pericardial tamponades were relieved by pericardiocentesis.The patients with stroke recovered well without any lingering effects.There was no death case.Conclusion Circumferential pulmonary vein linear ablation guided by 3-D mapping system is an effective therapy for atrial fibrillation patients with an acceptable safety.