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.

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.

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.

[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>