Preliminary study on left bundle branch area pacing in children: Clinical observation of 12 cases.

INTRODUCTION: Left bundle branch area pacing (LBBAP) maintains electrical and mechanical synchronization of the ventricles. It is a relatively physiological pacing mode, with low and stable pacing threshold and wider indications. LBBAP in children has been rarely reported. METHODS: This study observed 12 children attempted LBBAP from January 2019 to January 2021 in the department of pediatric cardiology of Anzhen Hospital prospectively. Clinical data, pacing parameters, electrocardiograms, intracardiac electrograms, echocardiographic measurements and complications were recorded at implant and during follow-up. RESULTS: The 12 patients aged between 3 and 14 years old and weighted from 13 to 48 kg. Eleven patients were diagnosed with third-degree atrioventricular block and 1 patient (case 4) suffered from cardiac dysfunction due to right ventricular apical pacing (RVAP). Left bundle branch area pacing was successfully achieved in all patients with narrow QRS complexes and V1 lead showed changes like right bundle branch block in the pacing electrocardiogram. Left ventricular ejection fraction in case 4 recovered on the 3rd day after LBBAP. The median of left ventricular end diastolic diameter Z score of the 12 patients decreased from 1.75 to 1.05 3 months after implantation (p < 0.05). The median of paced QRS duration was 103 ms. The median of pacing threshold, R-wave amplitude and impedance were 0.85 V, 15 mV and 717 Ω respectively and remained stable during follow-up. No complications such as loss of capture, lead dislodgement or septal perforation occurred. CONCLUSIONS: Left bundle branch area pacing can be performed safely in children with narrow QRS duration and stable pacing parameters. Cardiac dysfunction caused by long-term RVAP can be corrected by LBBAP quickly.

Pharmacoeconomic evaluation of empagliflozin in the treatment of heart failure with reduced ejection fraction / 中国药房

OBJECTIVE To conduct the pharmacoeconomic evaluation of empagliflozin in the treatment of heart failure with reduced ejection fraction （HFrEF），and to provide evidence-based reference for rational drug use and medical and healthy decision-making. METHODS A Markov model was used to perform a cost-effectiveness analysis of the regimen of empagliflozin in the treatment of HFrEF ，and to evaluate the cost and effectiveness of standard treatment plan plus empagliflozin （empagliflozin group）vs. standard treatment plan （standard treatment group ）. Clinical parameters were obtained from the EMPEROR-Reduced study；cost and utility data came from the published literatures. The cycle of the model was 1 month and the simulation time was 20 years. Single-factor sensitivity analysis and probability sensitivity analysis were performed to validate the results of cost-effectiveness analysis. RESULTS Compared with the standard treatment group ，each additional quality-adjusted life year in the empagliflozin group cost 37 995.94 yuan more ，which was less than China ’s 1 time GDP per capita in 2020（72 447 yuan）. The results of single factor sensitivity analysis showed that steady-state hospitalization rate of 2 groups was the most important factor affecting the incremental cost-effectiveness ratio . The results of probability sensitivity analysis showed that when the willingness-to-pay threshold （WTP）was 1 time GDP per capita in 2020（72 447 yuan），the probability of empagliflozin group with cost-effectiveness advantage was 58.8％；when the WTP was 3 times GDP per capita in 2020（217 341 yuan），the probability of empagliflozin group with cost-effectiveness advantage was 63.8％. CONCLUSIONS Compared with standard treatment plan alone，standard treatment plan plus empagliflozin is more cost-effective in the treatment of HFrEF. However ，the economic probability is not high.

Clinical analysis of cardiac tamponade complicating radiofrequency ablation of atrial fibrillation in elderly patients / 中华老年医学杂志

Objective:To investigate the association between age and cardiac tamponade after radiofrequency ablation of atrial fibrillation(RAAF).Methods:Clinical data of patients undergone de novo AF ablation procedures at Beijing Anzhen Hospital from January 2013 to December 2016 were retrospectively collected.Patients were divided into an elderly group(age ≥60 years)and a non-elderly group(age <60 years). Logistic regression analyses were used to evaluate the association between old age and the risk of cardiac tamponade complicating RAAF.Results:A total of 5 313 patients were involved in this study, including 41 patients(0.77%)with cardiac tamponade.The proportion of cardiac tamponade was higher in the elderly group than in the non-elderly group(1.1% or 32/2 950 vs.0.4% or 9/2 363, χ2=8.489, P=0.004). One patient with cardiac tamponade in the elderly group required immediate surgical repair whereas none in the non-elderly group did.No patient died in hospital.Multivariate Logistic regression analysis showed that the risk of cardiac tamponade increased in the elderly group, compared with the non-elderly group( OR=2.570, 95% CI: 1.190-5.570, P=0.017). Stratified analysis revealed that among females and patients with oral anticoagulants, left atrium dimension < 40 mm or procedure duration≥ 120 min in the elderly group carried a higher risk of cardiac tamponade than those in the non-elderly group( OR=1.011, 2.914, 3.922 and 3.244, P<0.05). Conclusions:Old age(age ≥60 years)is an independent risk factor for cardiac tamponade complicating RAAF.

Clinical analysis of left atrial appendage occlusion for stroke prevention in elderly patients with atrial fibrillation / 中华内科杂志

To evaluate the efficacy and safety of left atrial appendage occlusion (LAAO) in patients with atrial fibrillation (AF) over 75 years. A total of 82 patients with AF who underwent LAAO successfully in Beijing Anzhen Hospital from March 2014 to March 2019 were divided into two groups according to age: the elderly group (aged>75 years) and the young group (aged ≤75 years). Risk of perioperative complications and incidence of ischemic stroke and major bleeding during follow-up were retrospectively analyzed. The results showed that there were no significant differences in procedure-related ischemic stroke(0 vs.1.6%, P=0.768) and major bleeding (0 vs.1.6%, P=0.768) during perioperative period between the two groups. No complications as death or pericardial tamponade occurred in the two group. During a (25.9±15.9) months period of followed up, ischemic stroke event rate was 3.6/100 person-years in the elderly group and 4.9/100 person-years in the young group, respectively. Major bleeding event rate was 2.5/100 person-years in the elderly group and 0/100 person-years in the young group, respectively. Compared with the expected ones, the relative risk reduction (RRR) of stroke in the elderly group was more profound than that in the young group (32.0% vs. 25.0%), while the risk of major bleeding in the young group was significantly lower than that in the elderly group (RRR 100% vs. 56.9%). Therefore, LAAO might be suitable for stroke prevention in the elderly AF patients.

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.

A novel viral protein translation mechanism reveals mitochondria as a target for antiviral drug development

The ongoing Severe Acute Respiratory Syndrome coronavirus 2 (SARS-CoV-2) pandemic has acutely highlighted the need to identify new treatment strategies for viral infections. Here we present a pivotal molecular mechanism of viral protein translation that relies on the mitochondrial translation machinery. We found that rare codons such as Leu-TTA are highly enriched in many viruses, including SARS-CoV-2, and these codons are essential for the regulation of viral protein expression. SARS-CoV-2 controls the translation of its spike gene by hijacking host mitochondria through 5 leader and 3UTR sequences that contain mitochondrial localization signals and activate the EGR1 pathway. Mitochondrial-targeted drugs such as lonidamine and polydatin significantly repress rare codon-driven gene expression and viral replication. This study identifies an unreported viral protein translation mechanism and opens up a novel avenue for developing antiviral drugs. One Sentence SummaryMitochondria are a potential target for antiviral therapy

An effective, safe and cost-effective cell-based chimeric vaccine against SARS-CoV2

More than one hundred vaccines against SARS-CoV-2 have been developed and some of them have entered clinical trials, but the latest results revealed that these vaccines still face great challenges. Here, we developed a novel cell-based gp96-Ig-secreting chimeric vaccine which is composed of two viral antigens, the RBD of spike protein, and a truncated nucleocapsid protein that could induce epitope-specific cytotoxic T lymphocytes but low antibody response. Syrian hamsters immunized with the cell-based vaccine produced high level of SARS-CoV-2 specific NAbs and specific T cell immunity which could eliminate RBD-truncated N-expressing cells, without the induction of antibody against N protein and other observed toxicity. This study provides a proof of concept for clinical testing of this safe, effective and cost-effective vaccine against SARS-CoV2 infection.

Clinical characteristics of left atrial appendage thrombus in patients with hypertrophic cardiomyopathy and non-valvular atrial fibrillation / 中华心血管病杂志

Objective@#To investigate the incidence and clinical characteristics of left atrial appendage (LAA) thrombus in patients with hypertrophic cardiomyopathy (HCM) and non-valvular atrial fibrillation (AF) .@*Methods@#Data from 10 440 patients with AF who had undergone transesophageal echocardiography (TEE) before cardioversion or catheter ablation at Beijing Anzhen Hospital from April 2006 to December 2018 were retrospectively screened. Two hundred and five HCM patients were included, 820 AF patients with the same CHA2DS2-VASc score over the same period were selected as the control group. HCM patients were divided into two subgroups based on presence or absence of LAA thrombus/sludge. The baseline of clinical information, transthoracic echocardiographic and TEE measures were compared among all the groups. Receiver operating characteristic (ROC) curve was used to evaluate the diagnostic value of left atrial diameter (LAD) for LAA thrombus/sludge. Multivariate logistic regression analysis was applied to analyze the correlative factors of LAA thrombus/sludge in HCM patients.@*Results@#The incidences of LAA thrombus or sludge were higher in HCM group than in control group (10.7% (22/205) vs. 0.7% (6/820); 8.8% (18/205) vs.7.0% (57/820), P<0.001) . In HCM patients, LAD was significantly larger in LAA thrombus/sludge subjects than in those without thrombus/sludge ((48.9±5.1)mm vs. (45.2±6.1) mm, P<0.001). CHA2DS2-VASc score was similar between the two subgroups ((2.0±1.4) vs. (1.8±1.4), P>0.05). There was no difference in the rate of patients with a CHA2DS2-VASc scores ≥2 between the subgroups(62.5% (25/40) vs. 57.0% (94/165), P=0.525). The incidences of LAA thrombus in HCM and AF patients with CHA2DS2-VASc scores of 0, 1 and 2 were 8.8% (3/34) , 9.6% (5/52) , 11.8% (11/119) , respectively; and the rate of LAA sludge were 8.8% (3/52) , 7.7% (4/52) , 9.2% (11/119) , respectively. The cut off value of LAD for the diagnosis of LAA thrombus/sludge was 44.5 mm. Multivariate logistic regression analysis showed that LAD≥44.5 mm (OR=5.134, 95%CI 1.862-14.156, P=0.002) , non-paroxysmal AF (OR=2.782, 95%CI 1.238-6.252, P=0.013) , previous thromboembolism or stroke (OR=1.820, 95%CI 0.774-4.227, P=0.017) were independent determinants of LAA thrombus/sludge.@*Conclusions@#The incidence of LAA thrombus/sludge is higher in patients with HCM and AF than in AF patients without HCM. The CHA2DS2-VASc score is similar between HCM and AF patients with LAA thrombus/sludge and those without thrombus/sludge. Patients with CHA2DS2-VASc score 0-1 are also likely to suffer LAA thrombus/sludge. Left atrial enlargement is associated with LAA thrombus/sludge.

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.

Performance of interpreting the variants of long QT syndrome according ACMG guidelines by four clinical gene screening agencies from Beijing / 中华心血管病杂志

Objective@#To analyze the interpretation results on the pathogenic classification of KCNH2 variants and SCN5A variants of long QT syndrome (LQTS) based on American College of Medical Genetics and Genomics (ACMG) guidelines by 4 clinical gene screening agencies from Beijing.@*Methods@#Pathogenic classification of 16 variants in KCNH2 and SCN5A was made by 4 clinical gene screening agencies from Beijing based on ACMG guideline. Krippendorff's alpha was used to assess the inter-agency variation consistency.@*Results@#All 4 agencies made pathogenic assessment on all the variants and provided the interpretation results for the classification. For the eight variants from the patients with LQTS, the consistency of classification was only 1/8 and the alpha test value was - 0.01. For the eight variables from incidental findings, the consistency of classification was 4/8 and the alpha test value was 0.407. Evidence analysis of the 4 variants with large differences in classification among agencies showed that the main reasons for the discrepancies originated from the comprehensiveness of the literature search and the inconsistency of the subjective determination of the evidence grade.@*Conclusion@#The consistency of the pathogenic classification of LQTS gene variants based on ACMG guidelines among clinical gene screening agencies from Beijing is poor, which will result in great impact on the clinical treatment strategies of the patients with LQTS. The standardization of pathogenic evaluation of variants in clinical gene screening agencies needs to be improved urgently.

Efficacy and safety of three-dimensional electroanatomical mapping system for catheter ablation of paroxysmal supraventricular tachycardia in children / 中华心血管病杂志

Objective@#To evaluate the efficacy and safety of three-dimensional electroanatomical mapping system for catheter ablation of paroxysmal supraventricular tachycardiain (PSVT) children.@*Methods@#Clinical data from 187 children with paroxysmal supraventricular tachycardia undergoing radiofrequency catheter ablation in our department between January 2012 and April 2016 were analyzed. Among the patients, 91 cases were treated with traditional two-dimensional X-ray radiofrequency ablation, 96 cases were treated with radiofrequency ablation guided by three-dimensional electroanatomical mapping system. Postoperative electrocardiogram and echocardiography follow-up was performed at 1, 3, 6, 12, and 24 months. The success rate, recurrence rate, complication rate, operation time and amount of X-ray exposure were compared between the two groups. Kaplan-Meier survival curve was used to analyze the PSVT-free survival rate of the patients between the 2 groups.@*Results@#The mean follow-up time was (739±92) days. The success rate (95.8%(92/96) vs. 94.5%(86/91), P=0.912), recurrence rate (5.4%(5/92) vs. 4.7%(4/86), P=0.807), complication rate (4.2%(4/96) vs. 5.5%(5/91), P=0.379), operation time ((73±31)min vs. (79±36)min, P=0.124) were similar between the two groups. However, X-ray exposure time ((8.1±2.9)min vs. (21.3±8.4)min, P=0.026), amount of X-ray ((23±11)mGy vs. (58±23)mGy, P=0.013) were significantly lower in the three-dimensional electroanatomical mapping system group than in the traditional two-dimensional X-ray radio frequency ablation group. PSVT-free survival rate was similar between the two groups (χ2=0.060, P=0.807) .@*Conclusion@#Three-dimensional electroanatomical mapping system is safe and effective for radiofrequency ablation of paroxysmal supraventricular tachycardia in children, and can significantly reduce the amount of radiation as compared to the traditional two-dimensional X-ray radiofrequency ablation.

Effect of non-vitamin K antagonist oral anticoagulants on left atrial or atrial appendage thrombi in patients with nonvalvular atrial fibrillation / 中华心血管病杂志

Objective@#To investigate the effect of non-vitamin K antagonist oral anticoagulants (NOAC) on left atrial or atrial appendage (LA/LAA) thrombi in patients with nonvalvular atrial fibrillation (NVAF).@*Method@#Data from 3 042 patients with atrial fibrillation(AF), who underwent transesophageal echocardiography (TEE) examination before cardioversion or catheter ablation for the detection of LA/LAA thrombus in our department from March 2016 to January 2018 were prospectively analyzed. Among these patients, LA/LAA thrombus was detected by TEE in 57 patients. A total of 19 patients who received dabigatran or rivaroxaban for ≥3 weeks and underwent repeated TEE were included, 38 patients were excluded (7 patients with rheumatic heart disease, 1 patient treated with pericardial decortication, 1 patient treated with surgical repair of endocardial cushion defect, 1 patient with LA thrombus associated with the atrial septal occluder device, 14 patients received warfarin therapy, 14 patients did not receive repeated TEE).@*Results@#First repeated TEE results showed that LA/LAA thrombus was not completely resolved in 4 out of 4 patients treated with dabigatran (110 mg bid) for a median time of 119 (47, 258) days, whereas LA/LAA thrombus was completely resolved in 5 out of 11 patients treated with dabigatran (150 mg bid) for a median time of 80 (58, 147) days. Thrombus was completely resolved in 2 out of 2 patients treated with rivaroxaban (15 mg qd) for 110 days and 95 days respectively, and in 1 out of 2 patients treated with rivaroxaban (20 mg qd) for 91 days. Second repeated TEE was performed in 8 patients. Thrombus was resolved completely in 2 out of 3 patients with undissolved thrombus treated by dabigatran (110 mg bid) after increasing the dabigatran dosage (150 mg bid). Thrombus was resolved in 3 (1 patient prolonged treatment with dabigatran 150 mg bid and 2 patients switched to rivaroxaban 20 mg qd) out of 4 patients with undissolved thrombus under the dabigatran 150 mg bid regimen, whereas the thrombus remained unresolved in 1 patient switched to rivaroxaban (15 mg qd). After receiving rivaroxaban 15 mg bid treatment, the thrombus was finally resolved in 1 patient with undissolved thrombus treated by rivaroxaban 20 mg qd. There was no clinical thromboembolism or major bleeding events during the median follow up time of 462 (305, 558) days.@*Conclusions@#Our data show that NOAC is an effective therapeutic option for the treatment of LA/LAA thrombi. When eligible, a higher NOAC dosage may be preferred due to the higher efficacy on thrombus resolvement.

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.

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.

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.

Evaluation of diffuse myocardial fibrosis of cardiomyopathy by using T1 mapping：initial study / 中华放射学杂志

Objective To investigate the value of contrast enhancement T1 mapping in detection of diffuse myocardial fibrosis in cardiomyopathy, and the relationship between myocardial fibrosis and cardiac function. Methods From September 2013 to September 2014, 76 cases of cardiomyopathy patients (including myocarditis) and 33 cases of healthy controls were enrolled in our study. All the subjects underwent cardiac MR (CMR) examination. Scan sequences included cine MR, pre-contrast and post-contrast T1 mapping and late gadolinium enhancement (LGE) imaging. The pre-/post-contrast left ventricle average T1 value and cardiac function of patients and controls were measured and compared by using independent-samples t test. According to the LGE imaging, all the subjects were subsequently divided into LGE positive group, LGE negative group and control group. The myocardial average T1 value and cardiac function among the three sub-groups were compared by using one-way ANOVA, and the relationship among them were analyzed by using Pearson correlation. Results Among the 76 cases of non-ischemia cardiomyopathy patients, 51 cases (67.1%) had LGE. Compared with controls, cardiomyopathy patients presented with higher pre-contrast T1 value [(1 306.4 ± 84.6)ms vs. (1 266.6 ± 57.3)ms, t=2.10, P0.05). There were correlation between pre-/post-contrast left ventricle T1 value and ejection fraction (EF) in cardiomyopathy patients (r=-0.252,-0.217, P0.05). Conclusions The average pre-/post-contrast T1 value in left ventricle myocardium are helpful for detection of diffuse fibrosis in cardiomyopathy patients. The LGE positive is a sign that can greatly change the T1 value of the myocardial tissue, meanwhile, myocardial fibrosis is negative correlated with ejection fraction in cardiomyopathy patients.

[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.

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>

Postablation neutrophil/lymphocyte ratio correlates with arrhythmia recurrence after catheter ablation of lone atrial fibrillation / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Neutrophil/lymphocyte ratio (NLR) has been proposed as a novel marker of systemic inflammation and oxidative stress. The objective of this study was to ascertain the relationship between levels of NLR and recurrence of lone atrial fibrillation (AF) after catheter ablation.</p><p><b>METHODS</b>A total of 379 lone AF patients who underwent catheter ablation were enrolled in the study. The NLR before and after catheter ablation was determined. Cox regression analyses were used to estimate the relationship between NLR and the recurrence of lone AF.</p><p><b>RESULTS</b>After a mean follow-up of (30.5 ± 5.3) months, 124 (32.7%) patients had AF recurrences. The patients who developed AF recurrence had a higher postablation NLR (post-NLR) than patients with no recurrence (5.74 ± 1.55 vs. 4.66 ± 1.27, P < 0.001). Multivariate Cox regression analysis revealed that post-NLR (hazard ratio (HR) 1.514, 95% confidence interval (CI) 1.364-1.680, P < 0.001), left atrium diameter (HR 1.035, 95% CI 1.001-1.071, P = 0.04) and body mass index (HR 1.028, 95% CI 1.002-1.054, P = 0.03) were independent predictors of AF recurrence. Using a cut-off level of 5.15, post-NLR predicted AF recurrence with a sensitivity of 73% and specificity of 67%.</p><p><b>CONCLUSIONS</b>Our results indicate that an elevated post-NLR is associated with a high rate of lone AF recurrence. A simple measurement of NLR may help us to identify high-risk patients who need pharmacologic intervention to prevent recurrence.</p>