[Comparison of clinical features of septic shock in children with hematological malignancies versus children without malignant tumors].

Objective: To investigate the clinical features of septic shock in children with hematological malignancies compared with those without malignant tumor in the pediatric intensive care unit (PICU). Methods: This retrospective study enrolled children with septic shock at the PICU of Capital Institute of Pediatrics' Children's Hospital from June 2015 to July 2022. According to the presence of hematological malignancies, patients were divided into the hematological malignancies group and without malignant tumor group. Clinical data were compared between the two groups, and logistic regression analysis was used to identify related factors for mortality. Results: A total of 164 children (97 males and 67 females) with a median age of 3.6 (interquartile range 0.8, 7.8) years were enrolled, including 75 (45.7%) patients with hematological malignancies and 89 (54.3%) patients without malignant tumors. Patients in the hematological malignancies group were older [6.0(3.6, 9.4) years vs 1.2 (0.4, 4.3) years, P<0.001] and more experienced hospital-acquired infections [48.0%(36/75) vs 21.3%(19/89),P=0.001], compared with patients without malignant tumors. Surgical emergencies were more frequent in patients without malignant tumors (32.6% vs 14.7%, P=0.013). Patients with hematological malignancies mainly had blood stream infections (58.7%), with Gram-negative bacilli (46.7%), meanwhile, patients without malignant tumors more experienced Gram-positive cocci infections (22.5%) of the respiratory system (40.4%) or digestive system (28.1%). There were significant differences regarding the infection sites (P<0.001) and pathogens (P=0.001). The types of antibacterial agents (P<0.001) and the frequency of noradrenaline (P=0.013) used in patients with hematological malignancies were significantly higher than those without malignant tumors. Patients with hematological malignancies had a higher incidence of multiple organ dysfunction (MODS) [100.0%(75/75) vs 80.9%(72/89), P<0.001] and higher 28-day mortality [34.8%(23/66) vs 19.0%(15/79),P=0.048]. Multivariate logistic regression analysis showed that Pediatric Critical Illness Score (PCIS) was an independent factor for death (odds ratio, OR=1.387, 95%CI: 1.161-1.657, P<0.001) in patients with hematological malignancies, and PCIS (OR=1.419, 95%CI: 1.140-1.767, P=0.002) and the 6-hour lactate clearance rate (OR=65.857, 95%CI: 2.953-1 468.638, P=0.008) were independent factors for death in patients without malignant tumors. Conclusions: Children with hematological malignancies were older, more frequently experienced bloodstream infections, and had a higher incidence of MODS and higher 28-day mortality. PCIS is related to poor prognosis of septic shock in children.

[Progress in immunologic and genetic research of chronic obstructive pulmonary disease with lung cancer].

Chronic obstructive pulmonary disease (COPD) and lung cancer are two of the respiratory diseases with the highest mortality, which have posed huge threat to human health and brought great burden to society and family. The mechanism of COPD with lung cancer is very complicated. In order to clarify the linkage between these two diseases, this review summarized the present researches of COPD and lung cancer from the aspects of immunology and genetics. The immunologic aspect focused on innate immune of neutrophil and macrophage, adaptive immune of B cell, T cell and oxidative stress. The genetic aspect focused on susceptibility gene and microRNA. Through the thorough elaboration of these researches, we hope to provide useful insights into the further research of mechanism, diagnosis and targeted therapy of COPD with lung cancer.

[Value of heart rate-blood pressure product of multiplication for identifying compensated shock in children].

Objective: To estimate the predictive value of heart rate (HR)-blood pressure (BP) products of multiplication for compensated shock in children. Methods: The study population consisted of 99 children with shock who had lactate measured before receiving vasopressor agents in Department of Critical Care Medicine of Children's Hospital, Capital Institute of Pediatrics from October 2015 to March 2021. The clinical data including the HR, BP, HR to BP ratio, HR-BP product and lactate at admission and after the correction of shock, as well as the 28-day mortality were collected. According to the outcome at the 28th day, the patients were divided into survival group and non-survival group. Comparisons between groups were performed with unpaired Student t test, or Mann-Whitney U test, or chi-square test. Pearson correlation analysis was used to analyze the correlations between lactate and HR, BP, HR to BP ratio and HR-BP product, respectively. Receiver operating characteristic (ROC) curve was analyzed to evaluate the predictive values of HR, BP, HR to BP ratio and HR-BP product for lactate greater than 2 mmol/L. Results: In these 99 children, 49 were males, and the median age was 3.8 (0.7-6.0) years. The most common type of shock was septic shock (61 cases, 62%), followed by cardiogenic shock (12 cases, 12%), hemorrhagic shock (12 cases, 12%), Kawasaki disease shock syndrome (8 cases, 8%) and anaphylactic shock (6 cases, 6%). Sixty-six patients (67%) survived, and 33 patients (33%) died. ROC curve showed that the area under curves (AUC) of lactate (optimal cutoff value 3.15 mmol/L, sensitivity 96.0%, specificity 54.4%, P<0.01) and HR to systolic blood pressure ratio (HR/SBP) (optimal cutoff value 2.0 times/(min·mmHg), sensitivity 62.5%, specificity 69.0%, P = 0.03) for predicting adverse outcome were 0.769 and 0.649, respectively. There were significant correlations between lactate and HR to diastolic blood pressure (DBP) ratio, HR to mean blood pressure (MBP) ratio, SBP, HR/SBP, MBP, DBP and HR (r= 0.476, 0.452, -0.444, 0.425,-0.410, -0.364, 0.177, all P<0.01), while no significant correlation was found between lactate and the products of HR and BP(all P>0.05). HR/SBP performed better than the other six parameters for predicting lactate>2 mmol/L, with the AUC of 0.872 and the optimal cutoff value of 1.4 bpm/mmHg (sensitivity 92.1%, specificity 70.9%, P<0.01). When MBP was greater than or equal to 65 mmHg, MBP × HR, DBP × HR, SBP × HR, HR, HR/SBP, HR/MBP and HR/DBP were significantly correlated with lactate (r= 0.706, 0.705, 0.669, 0.626, 0.555, 0.502, 0.446, all P<0.01). And MBP × HR performed better for predicting lactate>2 mmol/L than the other six parameters, with the AUC of 0.974 and the optimal cutoff value of 9446 bpm × mmHg (sensitivity 100.0%, specificity 90.9%, P<0.01). Conclusions: The product of HR and BP, especially the MBP × HR, shows higher predictive values for abnormally elevated lactate in children with compensated shock than the HR/SBP does. It is worth recommending for early identification of compensated shock in children.

[Clinical characteristics and radiofrequency ablation of focal atrial tachycardia in 125 children].

Objective: To investigate the clinical characteristics of focal atrial tachycardia (FAT) and the efficacy of radiofrequency catheter ablation (RFCA) in pediatric FAT. Methods: A total of 125 children with FAT who were treated with RFCA in the First Hospital of Tsinghua University from January 2010 to July 2018 were involved in the study. The clinical characteristics, origin of FAT, success rate of RFCA and recurrence rate and complications post RFCA were retrospectively analyzed, and the efficacy and X-ray radiation were compared between two-dimensional (2D) and 3D mapping system by t test or Chi-square analysis. Results: Among the 125 children, 57 were males and 68 females, age of (7.6±3.5) years old and body weight of (27.7±13.3) kg; and 62 (49.6%) had paroxysmal FAT, and 63 (50.4%) incessant FAT. Twenty-seven patients (21.6%) presented with tachycardia-induced cardiomyopathy (TIC), and 22 of whom (81.5%) were secondary to the incessant FATs. Most of the FATs originated from atrial auricle (46/125, 36.8%). Ablation was successful in 111 children (88.8%), and the recurrence rate was 25.2% (28/111). No complications were identified in the whole group. The efficacy and safety of 3D mapping system (87 cases) was better than that of the 2D mapping system (38 cases), according to the lower recurrence rate ((19.0% (15/79) vs. 40.6% (13/32), χ2 = 3.849, P=0.049), shorter X-ray exposure time ((4.9±2.3) vs. (12.5±5.7) min, t=7.942, P<0.01) and lower radiation doses ((5.3±3.3) vs. (10.9±3.7) mGy, t=8.038, P<0.01). Conclusions: FAT in children is mainly originated from atrial auricle, and incessant FAT is prone to progress to tachycardia-induced cardiomyopathy. RFCA is safe and effective for drug-resistant or drug-intolerant FAT in children, and 3D mapping system should be preferred.

[Transthoracic implantation of dual-chamber pacemaker for synchronous treatment of cardiac dysfunction due to idiopathic complete left bundle branch block in children].

Objective: To investigate the efficacy and feasibility of transthoracic implantation of permanent left atrial and left ventricular dual-chamber pacemaker for synchronous treatment of cardiac dysfunction due to idiopathic complete left bundle branch block (CLBBB) in children. Methods: The clinical data of five children with cardiac dysfunction due to idiopathic CLBBB and accepting implantation of permanent left atrial and left ventricular epicardial dual chamber pacemaker from January 2015 to July 2019 at the Pediatric Cardiologic Department of the First Hospital of Tsinghua University were analyzed retrospectively. The effects of pacemaker implantation on patients' cardiac function and cardiac synchrony were evaluated by echocardiogram. Results: Among 5 patients, 2 were males and 3 females. At the time of pacemaker implantation, the age of these patients was 0.5-5.7 years, the left ventricle ejection fraction (LVEF) was 29%-46%, the left ventricle end stage of diastolic diameter was 30-53 mm and the mean Z score was 4.0-34.0. Pacemaker was successfully implanted for all the patients. After the implantation, medications that can suppress atrioventricular node conduction were used and sensed atrioventricular delay (SAV) parameters were modulated until patients' QRS duration became shortest and the percentage of left ventricular pacing increased to and maintained at 97% to 100%. Patients' QRS duration was 120-160 ms before implantation and 90-120 ms after implantation. Patients' cardiac function began to improve 1 day to 1 month after implantation. Patients' cardiac function normalized after a mean of 1-12 months. LVEF increased from 29%-46% to 55%-67%. During the follow-up, interventricular mechanical delay, septal-to-posterior wall motion delay, and left ventricular systolic dyssynchrony index decreased significantly: IVMD decreased from 31-62 ms to 26-50 ms; SPWMD decreased from 40-63 ms to 10-50 ms and Ts-SD decreased from 34.3-50.3 ms to 16.3-31.4 ms. The global longitudinal strain of left ventricle decreased from -7.7%--13.8% to -13.5%--20.3%. Conclusion: Cardiac dysfunction due to CLBBB in children can be treated with transthoracic implantation of permanent epicardial left atrial and left ventricular dual chamber pacemaker which can substitute three chamber pacemaker to achieve the effects of synchronous therapy that lead to reversion and normalization of cardiac function.

[Applicational value of 2017 ACR TI-RADS stratification in diagnosing thyroid nodules].

OBJECTIVE: To summarize and evaluate the value of applying the thyroid imaging reporting and data system (TI-RADS) released by American College of Radiology (ACR) in 2017 of the thyroid classification, and to propose an optimized classification method based on the result to facilitate more accurate and precise risk stratification of thyroid nodules. METHODS: In the study, 342 thyroid nodules assessed by 2017 ACR TI-RADS were retrospectively analyzed. Each nodule had a score, and all the scores of nodules were compared with the pathological results. The proportion of malignant nodules in different scoring ranges was obtained. The diagnostic efficacy of all nodules, nodules above 1 cm and less than or equal to 1 cm was evaluated by ROC curve, respectively. RESULTS: The AUC of all nodules, nodules above 1 cm and less than or equal to 1 cm were 0.907, 0.936 and 0.717, respectively. With the increase of the scores, the proportion of benign nodules decreased gradually, and the proportion of malignant nodules increased, especially nodules of 4-6 scores increased significantly. Based on the proportion of malignant nodules with 3 scores, the proportion of malignant nodules with 4, 5 and 6 scores increased 1.6, 3.8 and 5.3 times, respectively. The proportion of malignant nodules with 6-8 scores was 81%-84%, while the proportion of malignant nodules with 9 scores or more was 93%-94%. According to the distribution characteristics of malignant nodules, the classification of TI-RADS was adjusted. TI-RADS 4 was divided into TI-RADS 4a, TI-RADS 4b and TI-RADS 4c, corresponding to 4, 5 and 6-8 scores respectively, while the nodules with 9 scores or more were divided into TI-RADS 5. CONCLUSION: 2017 ACR TI-RADS has high diagnostic value for thyroid nodules above 1 cm, but it is not so effective for the nodules less than or equal to 1 cm. According to the proportion distribution of malignant nodules in different scoring ranges, appropriate adjustment of classification will be more accurate and precisely predict the malignant risk of nodules.

[Clinical and prognostic analysis of accessory pathway-induced dilated cardiomyopathy after catheter ablation in children].

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.

[Clinical characteristics and treatment of congenital long QT syndrome in 58 children].

Objective: To assess the clinical characteristics, pathogenic genes and therapeutic effects of congenital long QT syndrome (LQTS) in children. Methods: A retrospective analysis included 58 LQTS children (37 boys, 21 girls; age of diagnosis (8.0±4.1) years, range 0.1 to 16.0 years) at Division of Pediatric Cardiology, First Hospital of Tsinghua University from August 2013 to November 2017. Each patient was evaluated with a detailed medical history, 12-lead resting electrocardiogram, Doppler echocardiography, and molecular genetic analysis. Results: Forty-eight of the children (83%) had a delay to diagnosis (0.7 (0.1, 2.0)years) and initially received a misdiagnosis. QT prolongation of unknown origin was found in 10 cases (17%), complex arrhythmic conditions in 27 cases (47%), myocarditis in 3 cases (5%), syncope of unknown origin in 3 cases (5%), epilepsy in 2 cases (3%), myocardial infarction in 1 case (2%), cardiomyopathy in 1 case (2%), and vasovagal syncope in 1 case (2%). Nine children presented with the positive family history of LQTS and three children had congenital nervous deafness. Twenty-one (36%) children presented with recurrent syncope, and 14 cases of whom had symptoms during physical activity and/or emotional stress. The common arrhythmias were ventricular arrhythmia (26 cases), sinus node dysfunction (18 cases), atrioventricular block (AVB) (12 cases), and atrial arrhythmia (6 cases). LQTS-associated pathologic or possibly pathologic mutations were found in 41 children (71%). Thirty-three children (57%) were treated with propranolol (22 cases), permanent pacemaker (PM) combined with propranolol (5 cases), PM (4 cases), and implantable cardioverter defibrillator (ICD) combined with propranolol (2 cases). Eighteen children (55%) were asymptomatic, thirteen children (39%) reported infrequent syncope, and one case (2%) died. Conclusions: LQTS in children is potentially malignant and present as phenotypic diversity and complex arrhythmias. LQTS-related pathogenic or possibly pathogenic mutations are identified in most of the children. Beta-blockers therapy is effective in reducing the risk of malignant cardiac events. Some children with LQTS should receive PM or ICD therapy.

[Clinical analysis of right atrial appendage aneurysms complicated by atrial tachyarrhythmias in three children].

Objective: To investigate the clinical features and results of treatment for right atrial appendage aneurysms complicated by atrial tachyarrhythmias in children. Methods: This retrospective study included three children with right atrial appendage aneurysm complicated by atrial tachyarrhythmias (aged 1.0 to 5.3 years, weight 10 to 17.1 kg) who were hospitalized at the Pediatric Cardiology Department (Heart Center) of the First Hospital of Tsinghua University (Beijing Huaxin Hospital) during the period from January 2016 through April 2018. The patients' clinical features, the results of electrocardiogram (ECG) and echocardiography, the effects of therapeutic interventions (antiarrhythmics, radiofrequency ablation, and surgical resection of right atrial appendage aneurysm) and the results of pathological assessment were analyzed. Results: Three cases of right atrial appendage aneurysm were diagnosed at 36 weeks of gestational age, 1 month and 4 months after birth respectively. In two cases, ECG showed alternating episodes of atrial tachyarrhythmias including atrial tachycardia, atrial flutter, and atrial fibrillation, and echocardiography showed aneurysmal dilatation of right atrial appendage. These two cases underwent right atrial appendage aneurysm resection. In the remaining one case of atrial tachycardia, echocardiography did not visualize important lesions in the right atrium, thus the intracardiac electrophysiologic study and radiofrequency ablation were performed; and focal atrial tachycardia originating from the apex of right atrial appendage was mapped but failed to be ablated; consequently, the patient received the right atrial appendage resection, in which the right atrial appendage aneurysm was found. Preoperative multiple antiarrhythmics showed only modest or no efficacy for all the three cases. The atrial tachyarrhythmias disappeared in all the three cases after right atrial appendage aneurysm resection. Postoperative atrial tachycardias associated with new foci of impulse formation developed in two cases. These two patients reverted to normal sinus rhythm and remained in this rhythm by using antiarrhythmics. Pathological assessment showed cystic dilation of parts of atrial cavity, fibrosis of cyst wall, generalized fibrosis of atrial myocardium combined with myocardial atrophy and cystic dilation, as well as uneven myocardial thickness with generalized myocardial interstitial fibrosis. Conclusions: For patients with congenital right atrial appendage aneurysm, atrial tachyarrhythmias might develop during fetal stage or early postpartum period. Reliance on echocardiography might often lead to the missed diagnosis. These patients with atrial tachyarrhythmias responded poorly to antiarrhythmics. Radiofrequency ablation might be associated with a high risk and limited efficacy. Surgical resection of right atrial appendage aneurysm showed satisfactory results and should be highly recommended.

[3D electronic anatomy mapping guided radiofrequency catheter ablation in 95 children with atrioventricular nodal reentrant tachycardia].

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, r(2)=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, r(2)=0.001, P=0.780) and CSo-His (Y=0.072X+9.914, r(2)=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·cm(2), 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.

[An analysis of clinical characteristics and acute treatment of supraventricular tachycardia in children from a multicenter study].

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, χ(2) 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) (χ(2)=20.524, P=0.000). Paroxysmal SVT had a higher termination rate on pharmacological therapy than AT (67.1% vs. 50.0%, χ(2)=6.337, P=0.042). Patients of different age groups had significantly different response to antiarrhythmic therapy (χ(2)=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.

[Clinical challenges in the management of catecholaminergic polymorphic ventricular tachycardia in children].

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.

[Multicenter investigation of the correlation between supraventricular tachycardia and tachycardia-induced cardiomyopathy in children].

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 χ(2) 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%, χ(2)=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%, χ(2)=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.

[Clinical features and outcomes of radiofrequency catheter ablation of atrial flutter in children].

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.

Ghrelin to obestatin ratio in maternal serum in pregnancies complicated by intrauterine growth restriction.

Ghrelin, an endogenous for the growth hormone secretagogue receptor, has been shown to participate in fetal growth. Obestatin, encoded by the same gene as ghrelin, is described as a physiological opponent of ghrelin. This study was designed to determine the changes of ghrelin/obestatin ratio in maternal serum in pregnancies with intrauterine growth restriction (IUGR). The authors found that the ghrelin levels in maternal serum were significent lower in IUGR group than in control group (236.34 ± 14.58 pg/ml vs. 321.49 ± 18.19 pg/ml, p = 0.003). However, the difference of obestatin levels in maternal serum in IUGR group than in control group was not significent (276.25, ±20.54 pg/ml vs. 256.34 ± 21.21 pg/ml, p = 0.308). The ratio of ghrelin to obestatin in maternal serum were significent lower in UGR group than in control group (1.05 ± 0.09 vs. 0.82 ± 0.08, p = 0.03). Meanwhile, the maternal serum growth hormone (GH) concentration in IUGR group was lower than that in control group (1.08 ± 0.08 pg/ml vs. 1.41 ± 0.09 pg/ml, p = 0.009), and the maternal serum pla- cental growth hormone (PGH) concentration in IUGR group was lower than that in control group (2.21 ± 1.24 pg/ml vs. 2.92 ± 0.27 pg/ml,p = 0.031). The ratio of ghrelin to obestatin in maternal serum were positively correlation with GH and PGH concentrations in IUGR group (r = 0.876, p = 0.52; r = 0.764, p = 0.64). The findings of this study suggest that the ratio of ghrelin to obestatin in maternal serum were low, and were positively correlated with GH and PGH concentration in IUGR group, which can been considered as evidencees of ghrelin/obestatin balance disorder role in pathogenesis of IUGR.

[Use of P-wave polarity during atrial tachycardia to predict site of origin in children].

OBJECTIVE: To perform a detailed analysis of the P-wave polarity in focal atrial tachycardia (FAT) on the basis of surface electrocardiograms (ECGs) and construct an algorithm for identification of the anatomic site of origin in children. METHOD: P-wave polarities for 40 consecutive children(14 boys and 26 girls, mean age of(8±3)years) with FAT undergoing successful radiofrequency ablation of a single atrial focus at First Hospital of Tsinghua University (2009-2014) were analyzed retrospectively from 12-lead ECGs during tachycardia.P waves were classified as positive, negative, isoelectric, or biphasic.The relations between P-wave and anatomic site of origin were analyzed using a chi-square test. RESULT: The P-wave polarities in leads V1(χ(2)=23.509, P=0.000) andⅠ(χ(2)=14.315, P=0.001) were significantly helpful in distinguishing left from right atrial origin of the tachycardia focus.The P-wave in lead V1 of a left atrial tachycardia was always positive or isoelectric in tachycardia.The P-wave in leadⅠof a right atrial tachycardia was always positive or isoelectric during tachycardia.The P-wave polarities in leads Ⅱ, Ⅲ, aVR and aVF(χ(2)=26.447, 23.974, 19.613, 17.415, all P=0.000)distinguished superior from inferior atrial foci significantly.Tachycardia arising from the superior foci (n=22) had positive P waves in leads Ⅱ, Ⅲ and aVF ( 95% (n=21), 86% (n=19), 95% (n=21), respectively) and negative P wave in lead aVR (73%, n=16). The P-wave was frequently negative in leads Ⅱ, Ⅲ and aVF(n=12) and positive in lead aVR (n=11) for a tachycardia arising from the inferior foci (n=18). The anatomic sites of FAT in children located mainly at right atrial appendage (23%, n=9), coronary sinus (18%, n=7), left atrial appendage (15%, n=6) and right superior pulmonary vein (10%, n=4). CONCLUSION: The anatomic sites of FAT in children are located mainly at right and left atrial appendage, coronary sinus and right superior pulmonary vein.P-waves in leads V1 andⅠprove to be significantly useful in differentiating left from right atrial tachycardia foci.P-waves in leads Ⅱ, Ⅲ, aVR and aVF are helpful in distinguishing superior from inferior atrial foci.

[Efficacy of radiofrequency catheter ablation of outflow tract ventricular arrhythmias in children].

OBJECTIVE: To explore the features of outflow tract ventricular arrhythmias (OTVA) in children and evaluate the efficacy and experiences of radiofrequency catheter ablation (RFCA). METHOD: Data were collected and analyzed on 53 consecutive pediatric patients who underwent RFCA for OTVA from January 2012 to July 2015 in the First Hospital of Tsinghua University. These children included 34 male and 19 female, whose average age was (8±3) years and body weight was (33±13) kg. All the children met the indication criteria for RFCA of OTVA in children. Data were analyzed about the onset age, the forms and ablation efficacy and strategies of OTVA. RESULT: The average age of onset was (8±4) years. Of these children, 68% (36/53) had frequent premature ventricular complex which was the main arrhythmia pattern.The proportion of 66%(35/53) were of right ventricular outflow tract (RVOT). The vast majority of RVOT ventricular arrhythmias originates from myocardium with in the first 1 cm beneath the pulmonary valve(89%, 31/35) or the septal region(77%, 27/35). The total acute success rate was 98%(52/53), the recurrence rate on follow-up was 10% (5/52) and the complications of the procedure was 2%(1/53). The X-ray exposure dose was(743±323) mGay·cm(2). However, for 6 of the children RFCA on both sides of outflow tract was necessary for success. CONCLUSION: OTVA in children originates mostly from RVOT. RFCA can be used for ablation of pediatric OTVA effectively and safely. In some cases, successful RFCA should be performed on both sides of outflow tract.

Identification and expression analysis of YABBY family genes associated with fruit shape in tomato (Solanum lycopersicum L.).

YABBY family genes play important roles in the development of leaf, flower, and fruit. The purpose of this research was to integrate all the YABBY genes and analyze the correlation between gene expression and fruit shape in tomato. Scanning of 24 genomes of sequenced species demonstrated that YABBY genes were very normal and stable in flowering plants except the seedless plants. Nine YABBY genes in tomato were computationally and experimentally characterized. The phylogeny was constructed based on whole proteins or the YABBY domain, and five distinct clades were observed as described in other angiosperms. A comparison of the expression patterns in tomatoes with large differences in fruit shape and/or size suggested that during the fruit development, YABBY genes had both negative and positive functions. The obtained information could provide a deeper understanding of the evolution of YABBY genes and can also be useful for tomato yield and shape breeding.

Differentiation of pleomorphic adenoma and Warthin's tumour of the salivary gland: is long-to-short diameter ratio a useful parameter?

AIM: To determine the utility of the long-to-short diameter ratio (L/S ratio) and other sonographic features in the differentiation of pleomorphic adenoma (PA) and Warthin's tumour (WT) of the salivary gland. MATERIAL AND METHODS: From 2003 to 2013, 100 patients with 100 PAs and WTs were included in this ethics committee-approved retrospective study. For each lesion, B-mode sonographic and colour Doppler images were obtained and the L/S ratios were calculated. Surgical excision and histopathological examination were accomplished in all cases. Differences between the L/S ratio and other sonographic features for PA and WT were evaluated. RESULTS: Of the 100 salivary tumours, 80 were located in the parotid (37 PAs and 43 WTs), and 20 were in the submandibular gland (19 PAs and one WT). In the parotid, the L/S ratio was 1.38±0.21 for PA and 1.73±0.46 for WT. The L/S ratio of the WTs was higher than that of the PAs (p<0.001). Applying a cut-off of 1.519, the sensitivity, specificity, and accuracy for differentiation of PA and WT in the parotid were 69.8%, 81.1%, and 75%, respectively; however, the accuracy dropped to 42.9% in diagnosing masses with ≥50% macroscopic cystic structures. When those masses were excluded, the accuracy rose to 78.1%. CONCLUSIONS: The L/S ratio when used with other ultrasound features aids differentiation between PA and WT in the parotid gland; however, masses with macroscopic cystic structures ≥50% should not be judged by this parameter.