Objective To explore the application effect of weekly maintenance together for detection equipment by persons specifically designated.Methods Firstly carries on the preliminary training and the organization of the examination for all junior technicians and nurses,the appropriate persons were selected.Secondly,the recruited personnel were trained and as-sessed by the manufacturer or equipment engineers.After obtaining a certificate of conformity,weekly centralized mainte-nance for detection equipment officially began to implement in August 2014.Maintenance time was designated as every Wednesday afternoon or evening.Two months after the operation the test carried out by the head of clinical laboratory and the equipment department engineers in strict accordance with the week maintenance prcedures for each instrument and each item,and on-site questions.Other personnel also participated in the test as a control group.After half a year,the question-naire was sent to all the inspectors,and the satisfaction rate about the maintenance of the instrument was counted.Results Seven personnel selected to participate in the weekly maintenance,includings two senior technicians,three technicians and two nurses.Experimental personnel BC5390,UF-1000i,BH5100Plus and BH2100,C8000 and i2000,ADVIA2400 average score was significantly higher than the control group.Before and after the programme,the average number of failures of the instrument was reduced from 22 to 8 times and the average satisfaction rate of the inspection personnel was 83.0%±5.0%and 98.0%±2.0% respectively,and the difference was statistically significant.Conclusion Weekly centralized maintenance for detection equipment by persons specifically designated can truly implement instrument maintenance requirements,and at the same time with the implementation of the program,the failure times is greatly reduced,which is beneficial to improve the quality of inspection and to avoid the medical risks caused by TAT.

OBJECTIVEEctopic atrial tachycardia (EAT) is a common type of supraventricular tachycardia in pediatric population, and it can be resistant to antiarrhythmic drugs and lead to tachycardia induced cardiomyopathy (TIC) if not properly managed. This study assessed the clinical course and response to treatment of EAT in children.

METHODA retrospective review included 144 children at the First Hospital of Tsinghua University diagnosed with EAT from January 2009 to April 2014. The clinical detailed history, 12 lead ECG, 24-h Holter recording, echocardiography, response to therapy and follow-up were analyzed.

RESULTThe onset of EAT occurred at any age with a distribution with positive skewness, 57 children ≤1 years, 22 children > 1 - 3 years, 25 children > 3 - 6 years and 40 children ≥ 6 years of age. The percentages of the three tachycardia types were 36. 1% (n = 52) for incessant EAT, 52. 8% (n = 76) for paroxysmal EAT and 11. 1% (n = 16) for sporadic EAT, respectively. There were 115 patients received drug therapy in our hospital and in 72 cases the EAT was completely controlled. Antiarrhythmic therapy had been discontinued in 35 children with complete control. Normal sinus rhythm was observed by telemetry or Holter within 4 to 90 days and the mean duration of medical therapy was 310 days (range 15 to 608 days) in these children. The combination of sotalol and propafenone showed better effectiveness for control of children with EAT (54%, 41/76), compared with single sotalol (36%, 24/66) and the combination of amiodarone and metoprolol (30%, 7/23) (χ2 = 6. 296, P = 0. 043). Tachycardia type was able to predict the response to antiarrhythmic drugs for children with EAT, sporadic tachycardia had best control rate on pharmacological therapy compared with paroxysmal tachycardia and incessant tachycardia (94% (15/16) vs. 67% (42/63) vs. 42% (15/36), χ2 = 17. 925, P = 0. 000) . Acute success of radiofrequency ablation (RFA) in children who showed poor response to antiarrhythmic drugs was achieved in 45 of 49 (92%), ultimate success was achieved in 33 of 49 (67%). The incidence of TIC secondary to EAT was 18. 1% (n =26), and left ventricular ejection-fraction (LVEF) returned to normal in 23 children after successful control of EAT ((61 ± 4) % vs. (43 ± 5) %, t = - 10. 036, P = 0. 000). Side effects including abnormal thyroid function (in 3) and abnormal liver function (in 1) occurred in 4 (17%) of 23 children who received amiodarone and disappeared when amiodarone was discontinued.

CONCLUSIONEAT in children predominantly occurred in young infants and children. Incessant EAT comprised a great percentage. The combination of sotalol and propafenone provided the best results for control of children with EAT. RFA should be considered as a preferred treatment for older children who displayed poor response to medical therapy.

Amiodarone ; Anti-Arrhythmia Agents ; Cardiomyopathies ; Catheter Ablation ; Child ; Child, Preschool ; Echocardiography ; Electrocardiography ; Humans ; Infant ; Retrospective Studies ; Sotalol ; Tachycardia, Ectopic Atrial ; drug therapy ; physiopathology ; Tachycardia, Supraventricular ; drug therapy ; Ventricular Function, Left

This paper discussed the existing problems of Information System ( LIS) from six aspects, inclu-ding:the security and the expansion of the function, protection of patients′privacy, the establishment of emergency response mechanisms, authenticity and accuracy of data and the risks for auto-approval rules, etc.The authors also analysed the necessity of its rectification from the perspective of ethics, proposed improvement programme and suggestions: strengthening the safety management systems and data, ensuring special check the confidentiality of the project, protect the patient′s privacy;setting up emergency mechanism;hospital based on the actual workload and resources to determine the LIS function module; regularly checking the test data, to avoid occupational inju-ries;continuously improving the rigour of automatic approval rules.

Objective To evaluate the safety and efficacy of radiofrequency catheter ablation(RFCA)in chil-dren with tachycardia arrhythmias. Methods One hundred and twenty - three children under 3 years old with drug -refractory tachycardia underwent an interventional electrophysiology procedure and RFCA in Medical Center of Tsinghua University from April 1994 to December 2014,including 98 male and 25 female,and their average age was(22. 9 ± 9. 6)months(2 - 35 months)and body weight was(13. 64 ± 2. 80)kg(4. 66 - 19. 40 kg). The mechanism,RFCA methods,the success rate,recurrence rate and complication rate of the different types of tachycardia were investigated. Results Among these children,interventional electrophysiological study confirmed 94 cases(76. 4% ,94 / 123 cases) with atrioventricular reentrant tachycardia(AVRT),7 cases(5. 7% ,7 / 123 cases)with atrioventricular nodal reentrant tachycardia(AVNRT),3 cases(2. 4% ,3 / 123 cases)with focal atrial tachycardia(FAT),8 cases(6. 5% ,8 / 123 ca-ses)with atrial flutter(AF),5 cases(4. 1% ,5 / 123 cases)with idiopathic left ventricular tachycardia(ILVT),6 ca-ses(4. 8% ,6 / 123 cases)arrhythmia was not induced. RFCA was performed in 109 cases(88. 6% ,109 / 123 cases). The success rate of RFCA was 94. 5%(103 / 109 cases)and the recurrence rate was 6. 8%(7 / 103 cases). In 88 cases of AVRT,the success rate was 96. 6%(85 / 88 cases),and the recurrence rate was 8. 2%(7 / 85 cases). In 5 cases of AVNRT,the success rate was 100. 0%(5 / 5 cases). In 3 cases of FAT,the success rate was 33. 3%(1 / 3 cases). In 8 cases of AF,the success rate was 87. 5%(7 / 8 cases). In 5 cases of ILVT,the success rate was 100. 0%(5 / 5 cases), and there was no recurrence. The complication of RFCA was puncture vascular occlusion in 2 cases(1. 6% ,2 / 123 ca-ses),without other serious complications and death cases. In this group of children,the fluoroscopy exposure time was (11. 2 ± 5. 8)min(5. 7 - 18. 2 min)and dose area product(DAP)exposure was(954. 5 ± 117. 4)mGy × cm2(707 -2 201 mGy × cm2 ). Compared with the elder children(379 cases over 3 years old)of the exposure fluoroscopy time (10. 8 ± 6. 4)min(3. 9 - 20. 5 min)and DAP exposure(927. 5 ± 193. 4)mGy × cm2(439 - 3 201 mGy × cm2 ),there was no statistically significant difference(t = 0. 616,1. 463,all P ﹥ 0. 05). Conclusions AVRT was the most common type of arrhythmia in infants and a higher incidence of multiple accessory pathways was found in infants. Application of radiofrequency ablation to children with tachycardia arrhythmias can be relatively safe and effective to the infants with drug - resistant tachycardia.

Objective To explore the possibility of guiding clinical fast diagnosis and rational use of drugs by rapid detection of plasma digoxin concentration(PDC) with i4000.Methods The plasma samples of 132 patients were collected and digoxin concentration was detected by i4000,and the relationship between PDC and clinical effect was analyzed.Then,the regularities of distribution of digoxin concentration also analyzed according to the age and PDC.The patients whose PDC beyond the effective concentration 0.8 ～ 2.0 μg/L,were treated with adjusted dose respectively according to the circumstance and continuous monitoring of PDC.Results In 132 cases,PDC of 106 patients within the therapeutic dose,accounted for 80.30％,and the total effective rate was 86.36％ after treatment.The effective rates in ＜0.8μg/L group,0.8 ～2.0μg/L group and ＞2.0μg/L group were 10.91％,95.28％and 75.00％,respectively.After dosage adjusted for 1 1 cases with PDC ＜ 0.8μg/L and 4 cases ＞ 2.0μg/L,the PDC returned to the effective concentration.The PDC in over 60 years old group was higher than that in 50 ～ 60 years old group.Poisoning symptoms occurred in 7 cases,and symptoms disappeared through adjustment dosages.Conclusion The PDC detection by Abbott i4000 is rapid and easy to operate,and the result is accurate and reliable.

Objective To investigate the efficacy of permanent left ventricular epicardial pacing through left lateral thoracotomy in children with complete atrioventricular block (CAVB)or complete left bundle branch block (CLBBB)as well as its effects on heart synchronization.Methods Permanent left ventricular epicardial pacemakers were implanted through left lateral thoracotomy in 26 children with CAVB or CLBBB in Heart Center,the First Affiliated Hospital of Tsinghua University.These children aged (2.3 ±2.1 )years old (1 month -9 years old),weight (1 1 .2 ± 5.8)kg (5 -32 kg),among them 1 5 cases were male and 1 1 cases were female.Among the 26 patients,24 patients had CAVB and 2 patients had dilated cardiomyopathy secondary to CLBBB.Fifteen children who visited the Pediatrics Department for acute upper respiratory tract infection were chosen as control group.The efficacy of left ventricular epi-cardial pacemakers was analyzed and its effects on heart synchronization were observed by using tissue Doppler imaging (TDI).Results Implantations of pacemakers were successfully conducted in all the 26 patients with no complications associated with operations.Left atrial and ventricular dual chamber epicardial pacemakers were implanted in 21 patients and left ventricular single chamber epicardial pacemakers were implanted in 5 patients.Within the follow -up period of (28.2 ±1 5.1 )months (1 month -51 months),atrial and ventricular leads were 1 00% effective.No significant diffe-rence was found in atrial electrode sensing,ventricular electrode threshold and ventricular electrode impedance com-pared with those during implantation(P >0.05).For the 6 patients with preoperative cardiac insufficiency,their left ventricular diastolic diameters decreased from (48.50 ±1 1 .1 0)mm to (40.67 ±6.40)mm after operation,and the difference was significant (t =2.96,P =0.030);but left ventricular ejection fraction increased from 0.27 ±0.08 to 0.53 ±0.08 after operation,and the difference was significant (t =-5.02,P =0.004).Two patients with right ven-tricular pacing developed pacemaker syndrome and were switched to left ventricular epicardial pacing.Their cardiac function returned to normal 1 .5 and 2.0 years later,respectively.Fifteen patients received evaluation of heart synchroni-zation by TDI.No significant difference was found in LVEF,septal -to -lateral wall motion delay,septal -to -posterior wall motion delay and standard deviation of Standard deviation of the peak tissue velocity between these 2 groups(all P >0.05).Conclusions For children requiring epicardial pacing,left ventricular epicardial pacing is safe and effec-tive,which can protect left ventricular systolic synchronization,prevent or reverse the pacemaker syndrome.

Objective: To investigate the clinical features and evaluate the efficacy of radiofrequency catheter ablation (RFCA) guided by 3D electronic-anatomy mapping system (CARTO3 System) in children with atrioventricular nodal reentrant tachycardia (AVNRT). Methods: This was a retrospective case-controlled study. Data were collected from 95 children with AVNRT who underwent RFCA using CARTO3 System in the first hospital of Tsinghua University from January 2014 to December 2017. The onset age, characteristic of electrophysiology and anatomy feature of Koch triangle were analyzed. The efficacy and safety of ablation and X-ray fluoroscopy were compared with control 135 children with AVNRT who underwent RFCA without using CARTO3 System. The t test or the chi-square test was used for group comparison. Linear regression equation was established for correlation analysis. Results: The onset age of the 95 children (male 55, female 40; the average age (8.0±3.6) years) with AVNRT was (0.2-17.0) years and 23(24.2%) children were less than 3 years old. Electrophysiologic study showed that 84.2% (80 cases) was AVNRT-slow fast (SF), 11.6% (11 cases) AVNRT-slowslow and 4.2%(4 cases) AVNRT-fast slow. The phenomena of atrio-Hisian(AH) jump occurred in 65.3% and the interval of AH jump was (73.0±10.6) ms. The height of Koch triangle (CSo-His) was (22.3±5.8) mm and related with the weight of children (Y=0.171X+ 16.660, r²=0.224, P<0.001).The distance between the successful ablation target and the lowest point of His zone (ABL-His) was (11.7±2.6) mm. And there was no relation with the body weight(Y=-0.005X + 11.650, r²=0.001, P=0.780) and CSo-His (Y=0.072X+9.914, r²=0.030, P=0.171). The acute success rate was 97.9% (93/95) and recurrent rate was 5.4% (5/93) during follow-up. No obvious complication was reported. Compared with control group, the fluoroscopy time ((3.3±2.5) vs. (10.7±5.8) min, t=13.190, P<0.05), radiation dose ((5.4±4.9) vs. (15.5±6.3) mGy, t=13.660, P<0.05), and dose area product (514±445) vs. (2 478±415) mGy·cm², t=33.850, P<0.05) were decreased significantly. Conclusions AVNRT-SF was the most common type of AVNRT. AVNRT incidence in infant and toddlers is lower than that in elder children. CSo-His is correlated with the body weight. ABL-His is relatively fixed. There is no correlation between ABL-His and the body weight and also no correlation between ABL-His and CSo-His. RFCA of AVNRT in children using the CARTO3 system is safe, effective and minimizes X-ray fluoroscopy.

Objective: Catecholaminergic polymorphic ventricular tachycardia (CPVT) accounts for up to 10%-15% sudden cardiac death (SCD) in the children and young population. This study aimed to assess the current situation and challenges in CPVT clinical diagnosis. Method: A retrospective review included 11 children (7 male patients) at the First Hospital of Tsinghua University clinically diagnosed with CPVT from June 2014 to July 2017. Each patient was evaluated with detailed history, physical examination, resting 12-lead electrocardiogram(ECG), 24-h Holter, exercise stress test, Doppler echocardiography and genetic test. Result: During physical activity and/or emotional stress, ten children presented with recurrent syncope and one child presented with palpitation and chest distress. The mean age of symptom onset was 8.4 (4.0-13.7) years with a delayed diagnosis of 2.4 (0.04-5.00) years. Two children had a familial history of syncope or sudden death. Nine children were initially misdiagnosed as complex arrhythmic conditions (n=4), syncope of unknown origin (n=3), and drug-resistant epilepsy (n=2) treated with antiepileptic medication for several years. Bidirectional VT and (or) polymorphic VT were detected using Holter recording or exercise test ECG in all patients. Genetic test revealed CPVT-associated pathologic or possible pathologic mutations in nine patients. All patients were treated with beta-blockers. Six patients were asymptomatic, four patients reported infrequent syncope, and one sudden death occurred during a mean follow-up of 0.97 years. Conclusion CPVT mainly occurs in children and adolescents with recurrent syncope during physical activities and/or emotional stress. Early diagnosis of CPVT remains challenging due to delayed diagnosis or misdiagnosis. Detailed clinical history and exercise stress test improve the early diagnosis and intervention for CPVT patients.

Objective: To explore the clinical features of atrial flutter (AFL) and evaluate the efficacy of radiofrequency catheter ablation (RFCA) for AFL in children. Method: Data were collected and analyzed on 50 consecutive pediatric AFL patients (male 37/female 13) who underwent electrophysiology study and RFCA from February 2009 to November 2016 in a case observational study. The average age was (6.2±3.5) years and body weight was (23.7±13.5) kg. Heart structure was normal in 26 patients. Twenty-four patients had congenital heart disease (CHD) and among them 22 patients underwent repaired surgery before. Patients were followed-up for 1 month to 7 years after RFCA. Clinical features and the outcomes of RFCA in AFL patients were analyzed. Result: The average onset age was (4.2±3.3) years. Of these patients, 84% had persistent AFL and 16% paroxysmal AFL. AFL with sick sinus syndrome (SSS) occurred in 36% patients without statistically significant difference between the groups with and without CHD (38.9%(7/18) vs. 61.1%(11/18), respectively, P=0.239 5); 49 patients underwent RFCA except one case with atrial standstill during the procedure. The total acute success rate was 96%. The follow-up recurrence rate was 8%.No complication of the procedures was observed. The cavotricuspid isthmus-dependent AFL occurred in all patients without CHD. However, in the children with CHD after the repair surgery 10 (45%) cases were with cavotricuspid isthmus-dependent AFL, 4 (8%) with atrial scars-dependent AFL, and 8(16%) with both cavotricuspid isthmus and atrial scars-dependent AFL. Conclusion RFCA was effective and safe for pediatric AFL. There is no difference on the acute success rate, the follow-up AFL recurrence rate, as well as occurrence of SSS between the groups with and without CHD. AFL patients with CHD included the cavotricuspid isthmus-dependent AFL, atrial scars-dependent AFL or both.