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Objective@#To investigate the outbreak of mumps in a remote village school of Zhaoqing City, to evaluate and vaccine effectiveness ( VE ) of mumps containing vaccine (MuCV), so as to provide reference for the formulation of epidemic prevention and control strategies.@*Methods@#Through on site case investigations and interviews, case data and epidemic related epidemiological information were obtained. Descriptive and retrospective cohort studies were used to analyze the epidemic characteristics, explore risk factors, and evaluate the protective effect of vaccines.@*Results@#Totally 166 cases of mumps were found, and all of them were students. The total attack rate was 7.79% and the outbreak lasted for 60 days. The first case occurred on October 11th and the last case occurred on December 9th in 2018. Most of the cases aged from 10 to 13 years old, accounting for 66.27%. There were 96 male patients and 70 female patients, with no statistically significant sex difference in the incidence rate ( χ 2=2.40, P >0.05). Involving 28 classes, 11 of which had an incidence rate more than 10%, mainly distributed in grades 2, 4 and 6. There were statistically significant differences in incidence rates among different grades ( χ 2=96.89, P <0.01) and different floors ( χ 2=67.35, P < 0.01 ), with the third floor higher than the other floors. Twelve out of 58 boarding pupils were cases, and boarding pupils were 1.89 times higher in risk of contracting mumps than day students ( RR=1.89, 95%CI =1.10-3.23). Pupils without being given the shot of MuCV were higher in the infection rate than those having the shot ( χ 2=5.70, P <0.05), and the VE % was 35% (95% CI = 7%- 55%). The VE % of one dose was 34% (4%-54%), while the effectiveness of protection was declined with time ( χ 2 trend =6.53, P < 0.05). The effectiveness of vaccine almost diasappeared six years after the shot ( χ 2=1.12, P >0.05).@*Conclusion@#Delayed case report and isolation, low rate of receiving MuCV, and decreasing effectiveness of one shot MuCV are closely assocaited with the outbreak and ongoing spread of the epidemic.
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Background@#Antibiotic resistance is a significant public health concern around the globe.Antimicrobial peptides exhibit broad-spectrum and efficient antibacterial activity with an added advantage of low drug resistance. The higher water content and 3D network structure of the hydrogels are beneficial for maintaining antimicrobial peptide activity and help to prevent degradation. The antimicrobial peptide released from hydrogels also hasten the local wound healing by promoting epithelial tissue regeneration and granulation tissue formation. @*Objective@#This study aimed at developing sodium alginate based hydrogel loaded with a novel antimicrobial peptide Chol-37(F34-R) and to investigate the characteristics in vitro and in vivo as an alternative antibacterial wound dressing to treat infectious wounds. @*Methods@#Hydrogels were developed and optimized by varying the concentrations of crosslinkers and subjected to various characterization tests like cross-sectional morphology, swelling index, percent water contents, water retention ratio, drug release and antibacterial activity in vitro, and Pseudomonas aeruginosa infected wound mice model in vivo. @*Results@#The results indicated that the hydrogel C proved superior in terms of cross-sectional morphology having uniformly sized interconnected pores, a good swelling index, with the capacity to retain a higher quantity of water. Furthermore, the optimized hydrogel has been found to exert a significant antimicrobial activity against bacteria and was also found to prevent bacterial infiltration into the wound site due to forming an impermeable barrier between the wound bed and external environment. The optimized hydrogel was found to significantly hasten skin regeneration in animal models when compared to other treatments in addition to strong inhibitory effect on the release of pro-inflammatory cytokines (interleukin-1β and tumor necrosis factor-α). @*Conclusions@#Our results suggest that sodium alginate -based hydrogels loaded with Chol-37(F34-R) hold the potential to be used as an alternative to conventional antibiotics in treating infectious skin wounds.
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Objective:To explore the safety and efficacy of Propafenone in terminating paroxysmal supraventricular tachycardia (PSVT) in children and analyze the factors influencing the effectiveness.Methods:A retrospective study was conducted on 169 PSVT children treated with Propafenone in the Department of Pediatric Cardiology, Heart Center, the First Hospital of Tsinghua University from September 2014 to October 2021.There were 118 boys and 51 girls with an average age of (2.84±2.91) years (age range: 14 days-13 years). According to age, they were divided into ≤ 1-year-old group, >1-3-year-old group, >3-7-year-old group, and >7-year-old group.Mea-surement data were compared between groups using t-test and Mann- Whitney U test.Counting data were analyzed by χ2 test. Results:Among the 169 children with PSVT, 65 cases (38.5%) were below 1 year old, 47 cases (27.8%) were >1-3 years old, 40 cases (23.7%) were >3-7 years old, 17 cases (10.1%) were above 7 years old.About 24 cases (14.2%) were combined with congenital heart disease.A total of 153 cases (90.5%) had nonspecific symptoms at the first visit.A total of 4.1% (7/169 cases) were complicated with tachycardia-induced cardiomyopathy, and their left ventricular ejection fraction increased from (44.0±4.0)% to (53.7±6.9)% after successful control of PSVT ( t=-4.700, P=0.003). The complete termination of PSVT by intravenous Propafenone was achieved in 125 of 169 cases (74.0%, 125/169 cases). The complete termination rate after multiple times of administration (74.0%) was significantly higher than that after the first intravenous injection (53.3%, 90/169 cases) ( χ2=15.657, P<0.001). There was a significant difference regarding the complete termination rate between children ≤1 year old (60.0%, 39/65 cases) and those >1 year old (82.7%, 86/104 cases) ( χ2=10.696, P=0.001). For children ≤1 year old, 1.5 mg/kg Propafenone (51.1%, 23/45 cases) showed better efficacy for PSVT termination than 1.0 mg/kg Propafenone (20.0%, 4/20 cases) ( χ2=5.519, P=0.019). For children >1 year old, there was no significant diffe-rence between 1.5 mg/kg and 1.0 mg/kg Propafenone groups (57.9% vs.62.1%) ( χ2=0.180, P=0.671). The adverse reaction rate of intravenous Propafenone was 9.5% (16/169 cases). One case presented with severe hypotension, which occurred in a child with right cardiac insufficiency with tricuspid valve depression; 15 cases showed abnormal cardiac conduction and recovered spontaneously in a short time.There was no deterioration of cardiac function in children with mildly to moderately reduced cardiac function. Conclusions:It is relatively safe and effective to terminate PSVT in children with intravenous Propafenone.The complete termination rate is 74.0%, which is related to age, dose and times of administration.Despite of low incidence of side effects, Propafenone should not be used to treat PSVT with cardiac function which is significantly impaired or unclear secondary to persistent tachycardia.Special attention should be paid to cardiac function deterioration in these patients.
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Objective:To investigate clinical electrophysiological characteristics of idiopathic ventricular arrhythmias (VAs) and outcomes of radiofrequency catheter ablation (RFCA) in pediatric patients.Methods:A total of 328 consecutive pediatric patients with VAs and treated with RFCA in the First Hospital of Tsinghua University from January 2014 to December 2019 were recruited, involving 205 males and 123 females with the mean age of (7.8±3.9) years and the mean body weight of (32.8±17.7) kg.Their clinical electrophysiological characteristics, RFCA outcomes of different origins of VAs and complications were analyzed.Results:Among the 328 patients with the mean onset age of (5.4±4.1) years, 57.6% had frequent premature ventricular complex (PVC), 28.7% had paroxysmal ventricular tachycardia (VT) and 13.7% had incessant VT.A total of 38/328 cases (11.6%) VAs children were complicated with tachycardia-induced cardiomyopathy.Except for 13 cases of non-induced VAs, among 315 cases there were 152/328 cases (46.4%) originated from the ventricular outflow tract (including 46.1% of the origination of the right ventricular outflow tract septum, 27.6% of the origination of the left coronary cusp, 18.4% of the origination of the right coronary cusp, and 7.9% of the origination of the right ventricular outflow tract free wall), 55/328 cases (16.5%) originated from the tricuspid valve, 54/328 cases (17.4%) originated from the left posterior fascicle, 39/328 cases (11.9%) originated from the left posterior papillary muscle, 5/328 cases (1.5%) originated from multi-origin VAs, 3/328 cases (0.9%) originated from the left anterior fascicle, and 7/328 cases (2.1%) originated from other origins.Among 307/328 cases (93.6%) VAs patients receiving RFCA, 271/307 cases (88.3%) were instantly successful, 14/307 cases (4.6%) were effectively treated and 22/307 cases (7.2%) were invalid.During the follow-up time of 3 to 36 months, there were 42/271 cases (15.5%) recurrent cases.The mean radiation time and dose were (3.2±5.8) min, and (1.4±2.6) mGy, respectively.The mean dose-area product (DAP) was (384.2±42.6) mGy·cm 2.A total of 4/328 cases (1.2%) reported perioperative vascular complication.In 20 infant patients younger than 3 years, only 1 case was not induced during procedure of RFCA, and the remaining 19 cases were performed with RFCA, including 18/19 cases (94.7%) with an instant success and 4/18 (22.2%) recurrent cases during follow-up.There were 1/20 case (5.0%) had perioperative vascular complication caused by vascular puncture.No serious complications, such as myocardial perforation, cardiac tamponade and atrioventricular block were reported. Conclusions:The right ventricular outflow tract septum is the most common origin of the idiopathic VAs in pediatric patients.VAs originated from the ventricular outflow tract and tricuspid valve usually have an acceptable outcome following ablation.The recurrent rate is high following ablation in VAs cases originated from the left ventricular fascicle and posterior papillary muscle.RFCA is safe and effective for drug resistant or intolerant VAs in infants, but the surgical indications should be strictly mastered and operated by experienced pediatric electrophysiologists.The radiation dose of RFCA can be limited in a safe range under the guidance of the 3-dimensional mapping system.
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Objective:To identify the risk factors for cardiac events like recurrent syncope and fatal events in children with long QT syndrome (LQTS).Methods:A retrospective review involving 69 children with LQTS with the age of (7.6±4.2) years (43 male patients, 26 female patients) admitted in the Heart Center, Division of Pediatric Cardiology, First Hospital of Tsinghua University from August 2013 to March 2019 was conducted.Medical history, surface electrocardiogram, Doppler echocardiography and screening results of pathogenic genes of each patient were analyzed.Patients were divided into cardiac event group (32 cases) and non-cardiac event group (37 cases) according to the presence or absence of cardiac events like syncope or sudden death.Differences between 2 groups were compared using the independent sample Student′s t test and Chi- square test. Results:There were 32 cases among 69 children (46.4%) had recurrent syncope, involving 2 deaths, 14 cases among 69 children (20.3%) had a positive family history and 8 cases among 69 children (11.6%) had family history of sudden death.There were 52 cases among 69 children (75.4%) had arrhythmias.Among them, 32 patients (46.4%) with ventricular arrhythmia, including 11 cases (15.9%) with torsades de pointes (TdP). Ten LQTS-associated pathogenic or pathogenic pathologic mutations were found in 53 cases among 69 children (76.8%). Children with cardiac events had a younger mean age of onset [(4.7±4.1) years vs.(7.4±3.7) years, t=-2.856, P=0.006], a longer mean corrected QT (QTc) [(529±66) ms vs.(478±52) ms, t=3.537, P=0.001] and a higher incidence of TdP (34.4% vs.0%, P<0.001) compared with those who did not have cardiac events.Pathogenic mutations of KCNQ1 and KCNH2 were more frequent in children with cardiac events (62.5% vs.18.9%, χ2=14.178, P=0.001). Conclusions:Children with LQTS are prone to cardiac events.Children with a younger onset age, a longer QTc duration, malignant ventricular tachycardia and mutations of the KCNQ1 and KCNH2 genes are more frequently complicated by cardiac events.
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Objective:To explore the safety and efficacy of adenosine triphosphate (ATP) in terminating paro-xysmal supraventricular tachycardia (PSVT) in children and the correlation between its efficacy, age and dose.Methods:A retrospective analysis was performed on the clinical data, efficacy and adverse effects of intravenous ATP in 120 children who had received ATP emergency cardioversion among 1 488 children with PSVT hospitalized in the Department of Pediatric Cardiology, Heart Center, First Hospital of Tsinghua University from September 2014 to November 2019.There were 80 boys and 40 girls with the age of (3.50±3.66) years (25 d-15 years). As for the group comparison, the measurement data was subject to the independent samples t test and Mann- Whitney U test; the enumeration data was subject to χ2 test. Results:Among the 120 children with PSVT, there were 42 cases (35.0%) <1 year old, and 24 cases(20.0%) combined with congenital heart disease.There were 8.3% of them (10/120 cases) suffering from tachycardiomyopathy (TCM) secondary to PSVT, whose LVEF increased from (32.70±11.69)% to (40.50±11.63)% after successful control of PSVT ( t=-3.647, P=0.005). The complete termination of PSVT by intravenous ATP was achieved in 53 of 120 cases (44.2%). ATP was given at 0.3 mg/kg, 0.2 mg/kg and 0.1 mg/kg in dose, and the significant effective rate was 56.5%(13/23 cases), 36.4%(32/88 cases) and 0, respectively, which showed that there was a significant difference in the therapeutic effect between different dose groups ( χ2=10.058, P=0.007). There was a significant difference regarding the complete termination rate between children <1 year old and those ≥1 year old [31.0%(13/42 cases) vs.51.3%(40/78 cases), χ2=4.575, P=0.032]. For refractory PSVT, the intravenous ATP was performed based on the absence of cardioversion with continuous pumping of other antiarrhythmic drugs, which achieved a significantly complete termination rate of 55.6% (10/18 cases). The rate of ATP adverse reactions was 2.5%(3/120 cases), presented with sinus arrest in children >1 year old with the dose of 0.2-0.3 mg/kg. Conclusions:It was relatively safe and effective to terminate PSVT in children with ATP, which was related to dose and age.For refractory PSVT, ATP can be intravenously pushed on the basis of continuous pumping of other antiarrhythmic drugs, which can achieve a higher complete termination rate.
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Objective@#To investigate the clinical characteristics and prognostic factors after catheter ablation of accessory pathway (AP)-induced dilated cardiomyopathy (DCM) in children.@*Methods@#Data were collected and analyzed on 147 consecutive pediatric patients (81males and 66 females), who hospitalized in our pediatric heart center between January 2009 and August 2018 and received catheter ablation for ventricular pre-excitation (right AP). Thirty-one children were diagnosed as AP-induced DCM and 116 children with normal cardiac function served as control. Data including clinical characteristics, electrocardiogram (ECG), echocardiography, electrophysiological examination (EPS), successful ablation and follow up were analyzed.@*Results@#The median age at first examination was 3.07 (0.09, 5.83) years. The pre-hospital misdiagnosis rate was 87.1% (27/31). The incidence of the AP-induced DCM was 21.1% (31/147) and the rate of right anterior free wall accessory pathway (AP) was the highest (50.0%, 10/20). AP-induced DCM was more common in right free wall Aps (41.9%, 13/31) and right anterior free wall (32.3%, 10/31). 48.4% (15/31) cases had no supraventricular tachycardia (SVT). EPS showed that 29% (9/31) of the AP did not have retrograde conduction. The median follow-up time after successful catheter ablation was 8 (2, 36) months of AP-induced DCM group, LVDd was significantly decreased ((41.6±12.8)mm vs. (45.6±13.9)mm, P<0.01) and LVEF ((56.2±11.8)% vs. (40.8±12.5)%, P<0.01) was significantly increased after ablation. Cox regression analysis showed that LVEF was the predictor of the duration of cardiac function recovery (HR=1.08, 95%CI 1.01-1.15, P=0.03).@*Conclusions@#Misdiagnosis rate is high for children with AP-induced DCM, leading to the delayed treatment. All of the AP-induced DCM occurred in right APs and right anterior free wall APs is the highest. Right free wall APs and right anterior free wall are most common in AP-induced DCM. Catheter ablation is a safe and effective treatment option for these patients. The lower the LVEF, the longer the cardiac function recovery.
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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.
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Objective@#The study assessed the clinical characteristics and response to acute intravenous antiarrhythmic drug therapy of supraventricular tachycardia (SVT) in children.@*Methods@#This was a multicenter prospective descriptive study including 257 children from First Hospital of Tsinghua University, Peking University First Hospital, Children's Hospital Affiliated to Capital Institute of Pediatrics and Beijing Anzhen Hospital who received intravenous antiarrhythmic drug therapy for SVT from July 2014 to February 2017. The clinical and tachycardia features, response to intravenous antiarrhythmic drug therapy of these children were characterized. Statistical analyses were performed using t test, Mann-Whitney U test, χ2 test and H test.@*Results@#The onset of SVT occurred at any age with a distribution with positive skewness, 57.6% (n=148) children<1 year, 17.5% (n=45) children1~<3 years, 10.5% (n=27) children 3~<6 years and 14.4% (n=37) children ≥ 6 years of age. The percentages of SVT types were 49.4% (n=127) for atrioventricular reentry tachycardia (AVRT), 4.3% (n=11) for atrioventricular nodal reentry tachycardia (AVNRT), 26.8% (n=69) for unclassified paroxysmal SVT and 19.5% (n=50) for atrial tachycardia (AT), respectively. Tachycardia-induced cardionyopathy (TIC) secondary to SVT developed in 30 of 225 (13.3%). Left ventricular ejection fraction (LVEF) of the 27 children attacked by TIC returned to normal after successful control of SVT (41.1%±6.3% vs. 60.3%±9.2%, t=-10.397, P=0.000). Complete termination of SVT by antiarrhythmic drugs was achieved in 164 of 257 (63.8%), partial termination rate was 18.7% (48 of 257) and failure to terminate rate was 17.5% (45 of 257). Propafenone (complete cardioversion in 98 (73.1%) of 134) and amiodarone (complete cardioversion in 23 (76.7%) of 30) showed better efficacy for SVT termination than adenosine (complete cardioversion in 26 (44.1%) 59) (χ2=20.524, P=0.000). Paroxysmal SVT had a higher termination rate on pharmacological therapy than AT (67.1% vs. 50.0%, χ2=6.337, P=0.042). Patients of different age groups had significantly different response to antiarrhythmic therapy (χ2=13.904, P=0.031). Children<1 year of age showed the least response to antiarrhythmic drug therapy with complete termination in 51 (55.4%) of 92. Adverse effects occurred in 9 patients (3.5%): Four patients had severe hypotensive shock using propafenone (n=3) and adenosine (n=1), and 3 patients had sinus arrest using adenosine.@*Conclusion@#Most (57.6%) children with SVT have their first clinical episode within 1 year of age, and AVRT is the most common type. TIC occurs in 13.3% of children with SVT. Intravenous antiarrhythmic drug therapy has a 63.8% complete termination rate for children with SVT and incidence of adverse effects is 3.5%. Propafenone and amiodarone are more effective for SVT termination in children than adenosine. Serious adverse effects may occur when using propafenone.
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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.
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Objective@#This study aimed to investigate the correlation between supraventricular tachycardia (SVT) and tachycardia-induced cardiomyopathy(TIC) in children and assess the risk factors for the development of TIC.@*Method@#One hundred and eighty-three patients were recruited in four hospitals of Beijing diagnosed as SVT were divided into two groups depending on whether or not complicated with TIC. The age, gender, tachycardia type, ventricular rate during tachycardia, frequency of tachycardia episodes and duration of tachycardia were compared between the two groups and risk factors associated with TIC were analyzed. Statistical analyses were performed using t test, Mann-Whitney U and χ2 test.@*Result@#Totally 183 patients were included in this study (paroxysmal supraventricular tachycardia, PSVT, n=149; atrial tachycardia, AT, n=34). The incidence of TIC was 13.1%. There was significant difference regarding the incidence of TIC between children with AT and children with PSVT (26.5% vs. 10.1%, χ2=6.537, P=0.011). The percentage of AT in patients with TIC was significantly higher than patients without TIC (37.5% vs. 15.7%, χ2=6.537, P=0.011). Patients with TIC had a higher frequency of tachycardia episodes(2.5(1.0-4.8) beats/year vs 4.0(1.0-10.0) beats/year, Z=-2.223, P=0.026)and longer duration of tachycardia(11.0(1.1-36.0) h vs 2.5(1.0-12.0) h, Z=-2.154, P=0.031)compared with patients without TIC. Multivariate predictors of TIC was longer duration of tachycardia (OR=2.041, P=0.028).@*Conclusion@#TIC occurs in 13.1% of children with SVT. The incidence of TIC in children with AT is higher than in children with PSVT. Risk factor for the development of TIC is longer duration of tachycardia.
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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.
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This experimental study was designed to explore the possible mechanisms of Cariporide, a kind of Na+/H+ exchanger inhibitor, for protecting the lung from warm ischemia/reperfusion injury (WI/RI) of isolated rat lung model. Thirty isolated rat lungs were established on the Langendorff apparatus and randomly divided to three groups (n = 10, each): control group (C group), ischemia/reperfusion group (IR group) and Cariporide group (CP group). Mean pulmonary artery pressure (MPAP) and peak airway pressure (pAwP) were monitored continuously. At the end of reperfusion, right bronchoalveolar lavage was performed, bronchoalveolar lavage fluid (BALF) recovery rate (BALFRR) was recorded, and protein content in BALF was measured. Lung water content (LWC), malondialdehyde (MDA) and superoxide dismutase (SOD)of left lung tissue were measured; histomorphology evaluation was performed under light microscope and transmission electron microscope. In comparison with the data from IR group, BALF protein concentration, LWC, MDA content and MPAP content of reperfusion were significantly decreased, but SOD activity was increased in CP group. Histomorphologic feature also showed that pathological change significantly reduced in CP group. In this rat WI/RI model, the mechanism by which the selective Na+/H+ exchanger inhibitor (Cariporide) attenuates lipid peroxidation induced by WI/IR may be: preventing Ca2+ overload via inhibiting the transport of Na+/H2 exchanger-1 (NHE1) in the context of the coupled exchanger, thereby reducing the activation of xanthine oxidase pathway and oxygen free radical liberation which is dependent on certain intracellular Ca2+ concentration, and lastly promoting the endogenous antioxidative mechanism.