Hydrogen Sulfide Regulating Myocardial Structure and Function by Targeting Cardiomyocyte Autophagy / 中华医学杂志(英文版)

<p><b>Objective</b>Hydrogen sulfide (HS), a gaseous signal molecule, plays a crucial role in many pathophysiologic processes in the cardiovascular system. Autophagy has been shown to participate in the occurrence of many cardiac diseases. Increasing evidences indicated that HS regulates myocardial structure and function in association with the altered autophagy and plays a "switcher" role in the autophagy of myocardial diseases. The aim of this review was to summarize these insights and provide the experimental evidence that HS targets cardiomyocyte autophagy to regulate cardiovascular function.</p><p><b>Data Sources</b>This review was based on data in articles published in the PubMed databases up to October 30, 2017, with the following keywords: "hydrogen sulfide," "autophagy," and "cardiovascular diseases."</p><p><b>Study Selection</b>Original articles and critical reviews on HS and autophagy were selected for this review.</p><p><b>Results</b>When autophagy plays an adaptive role in the pathogenesis of diseases, HS restores autophagy; otherwise, when autophagy plays a detrimental role, HS downregulates autophagy to exert a cardioprotective function. For example, HS has beneficial effects by regulating autophagy in myocardial ischemia/reperfusion and plays a protective role by inhibiting autophagy during the operation of cardioplegia and cardiopulmonary bypass. HS postpones cardiac aging associated with the upregulation of autophagy but improves the left ventricular function of smoking rats by lowering autophagy.</p><p><b>Conclusions</b>HS exerts cardiovascular protection by regulating autophagy. Cardiovascular autophagy would likely become a potential target of HS therapy for cardiovascular diseases.</p>

A modified Calgary syncope syndrome score in the differential diagnosis between cardiac syncope and vasovagal syncope / 中华儿科杂志

<p><b>OBJECTIVE</b>This study aimed at analyzing the usefulness of a modified Calgary Syncope Syndrome Score in the differential diagnosis between cardiac syncope (CS) and vasovagal syncope (VVS) in children through a large sample clinical study.</p><p><b>METHOD</b>Totally 189 children [112 males, 77 females, aged 2 - 18 yrs, mean age (12.4 ± 3.1) yrs] with CS and VVS who were at the syncope clinic or admitted to the Department of Pediatrics, Peking University First Hospital from August 2002 to April 2011 were included in the study. The diagnosis was analyzed by a modified Calgary Syncope Syndrome Score and receiver operating characteristic (ROC) curve was used to explore the predictive value of different Calgary Syncope Syndrome Scores in differential diagnosis between CS and VVS.</p><p><b>RESULT</b>There were significant differences in the score between CS [-5.00(-7, 1)] and VVS [1(-4, 6)] (P < 0.01). When the score was ≤ -2.5, the sensitivity and specificity of the differential diagnosis between CS and VVS were 95.4% and 67.7%, respectively. Since the modified Calgary Syncope Syndrome Score was integer number, CS should be considered when the score was less than -3.</p><p><b>CONCLUSION</b>The modified Calgary Syncope Syndrome Score might be used as an initial diagnostic method in differential diagnosis between CS and VVS, based on the history of the patients.</p>

Clinical characteristics and follow-up study of tachycardia-induced cardiomyopathy in 12 children / 中华儿科杂志

<p><b>OBJECTIVE</b>Tachycardia induced cardiomyopathy (TIC), secondary to various tachyarrhythmias, is a reversible condition which can lead to cardiac enlargement and heart failure. The impairment of both structure and function of heart can be reverted completely or partially if tachyarrhythmias are ceased without delay. This study aimed to explore the clinical characteristics, therapeutic regimen and outcome of TIC in children.</p><p><b>METHODS</b>Clinical data of 12 children with TIC, who came from Peking University First Hospital from Feb. 2003 to Jun. 2009, were retrospectively analyzed and followed up. The echocardiogram data on admission were compared with those from 12 homochronous cases with idiopathic dilated cardiomyopathy matched with 12 TIC cases in age and gender.</p><p><b>RESULTS</b>Atrial tachycardia is the commonest arrhythmia in 12 TIC cases (75%). Four cases underwent catheterization for radiofrequency ablation and all succeeded. The cardiac rhythm of 6 out of 8 cases treated with drugs became sinus rhythm after 3 days to 2 weeks antiarrhythmic drugs treatment. The remaining 2 cases still retained atrial rhythm, but the ventricular heart rates declined to normal. The left ventricular end-diastolic dimensions of the 12 cases were decreased compared with those of pretherapy [(37.5 ± 5.3) mm vs. (43.0 ± 5.7) mm, P < 0.01], and the left ventricular ejection fractions were increased [(60.5% ± 5.6%) vs. (33.7% ± 10.3%), P < 0.01], after (3.4 ± 2.3) months. In our (4.3 ± 2.4) year-follow-up, all cases were fine, except in one case the tachyarrhythmia relapsed because of discontinuation of the drug treatment by her parents. The left ventricular end-diastolic dimensions in 12 TIC cases were smaller than those of the 12 age- and gender-matched idiopathic dilated cardiomyopathy [(43.0 ± 5.7) mm vs. (54.8 ± 7.5) mm, t = 7.9, P < 0.01], and the ejection fractions were higher [(33.7% ± 10.3%) vs. (21.8% ± 7.5%), t = 3.7, P < 0.01].</p><p><b>CONCLUSION</b>The diagnosis of TIC should be considered for the children with tachycardia, cardiac enlargement and cardiac insufficiency. The degree of cardiac enlargement and cardiac insufficiency might be of value for the differential diagnosis between TIC and idiopathic dilated cardiomyopathy. The rhythm control and ventricular rates control could all result in a favorite therapeutic efficacy.</p>

The value of the New York University Pediatric Heart Failure Index in chronic heart failure in children / 中华儿科杂志

<p><b>OBJECTIVE</b>The study was designed to explore the value of the New York University Pediatric Heart Failure Index (NYU PHFI) for diagnosing and grading chronic heart failure in children.</p><p><b>METHODS</b>Totally 105 children with chronic heart failure or structural heart disease but without signs and symptoms of heart failure were enrolled. They were diagnosed using modified Ross score, NYU PHFI and NT-proBNP, respectively. According to modified Ross score as the referent criteria, the diagnostic value of NYU PHFI in quantifying chronic heart failure severity in children was studied. Furthermore, according to the grading of heart failure using modified Ross score, the area under the ROC curves of NYU PHFI was examined, respectively, in order to find out the optimal cut-off point.</p><p><b>RESULTS</b>NYU PHFI score was positively correlated with the modified Ross score (r = 0.909, P = 0.000). According to modified Ross score, NYU PHFI scores in different severity of heart failure in children differed significantly (F = 80.034, P = 0.000). A significantly positive correlation was found between plasma NT-proBNP and modified Ross score, and between NT-proBNP and NYU PHFI score. Correlation coefficients between plasma NT-proBNP and modified Ross score, and between plasma NT-proBNP and NYU PHFI score were 0.752 and 0.918, respectively. The correlation between NYU PHFI and plasma NT-proBNP was superior to that between modified Ross score and plasma NT-proBNP. According to modified Ross scores of 0 - 2 as being without heart failure, 3 - 6 as mild degree of heart failure, 7 - 9 as moderate degree of heart failure and 10 - 12 as severe degree of heart failure, the areas under the ROC curve of the NYU PHFI diagnosing if heart failure was present, differentiating moderate from mild and severe from moderate heart failure were 0.982, 0.942 and 0.918, respectively, and the sum of sensitivity and specificity was favorite when 6, 10 and 13 scores were set as cut-off value diagnosing the presence of heart failure, differentiating moderate from mild, and severe from moderate heart failure, respectively. According to above classification of heart failure based on NYU PHFI score, plasma NT-proBNP concentration was significantly different in different degree of heart failure (F = 53.31, P < 0.001). Plasma NT-proBNP concentration in those without heart failure was significantly lower than that of mild heart failure, and it was also significantly lower in mild heart failure than that of severe heart failure.</p><p><b>CONCLUSION</b>NYU PHFI was highly valuable for diagnosing chronic heart failure in children and 0 - 6 scores as being without heart failure, 7 - 10 scores as mild degree, 11 - 13 scores as moderate degree and 14 - 30 scores as severe degree of heart failure could be used as the reference criteria of different severities of heart failure.</p>

Clinical characteristics of cardiac syncope in children / 中华儿科杂志

<p><b>OBJECTIVES</b>To explore the clinical characteristics of cardiac syncope (CS) in children, and understand their significance in predicting the cardiac syncope.</p><p><b>METHODS</b>Twenty-three patients were referred to our department for evaluation of syncope. The diagnosis of the above cases was cardiac syncope. Each patient was interviewed using a standard questionnaire. The clinical histories and standard baseline electrocardiogram were analyzed to identify the variables contributing to the diagnosis of CS in children.</p><p><b>RESULTS</b>A cardiac cause was identified in 23 syncopal patients presenting to the Department of Pediatrics, Peking University First Hospital: sick sinus syndrome in 7, congenital long QT syndrome in 4, third degree atrioventricular block in 2, supraventricular tachycardia in 2, ventricular tachycardia in 1, atrial fibrillation in 1, pacemaker dysfunction in 1, idiopathic pulmonary hypertension in 3, hypertrophic cardiomyopathy in 1, and dilated cardiomyopathy in 1. The average age of CS patients was 9 years. In totally 23 patients, exertion related syncope spells were found in 14 cases (60.9%), syncope spells at various position 7/23 (30.4%), absence of prodromes in 12/23 (52.2%), syncope spells with incontinence in 4/23 (17.4%), history of heart disease in 4/23 (17.4%). Abnormal standard baseline electrocardiogram was found in 21 cases (91.7%).</p><p><b>CONCLUSIONS</b>The children with cardiac syncope have overt clinical features, especially abnormal findings in electrocardiogram and exertion related syncope spells are the most common clinical features.</p>

Effect of selective alpha1 receptor agonist in the treatment of children with postural orthostatic tachycardia syndrome / 中华儿科杂志

<p><b>OBJECTIVE</b>The study was designed to examine the effect of selective alpha1 receptor agonist midodrine hydrochloride in the treatment of children with postural orthostatic tachycardia syndrome.</p><p><b>METHODS</b>Fifty-five children (23 male, 32 female, age 5 - 19 yrs, mean age 12.3 +/- 3.1 yrs) who came from Peking University First Hospital were included in the study and clinical investigations as well as standing test, basic head-up tilt test and sublingual nitroglycerin-provocated head-up tilt test under quiet circumstance were conducted. They were randomly divided into treatment group (with midodrine hydrochloride and oral rehydration salt treatment) and control group (with oral rehydration salt treatment only). At last, the disease-free rate, improvement rate and effective rate of symptoms, and the rate of HUT from positive to negative response were compared between control group and treatment group. SPSS 10.0 software was used for the statistical analysis of these data.</p><p><b>RESULTS</b>The symptom improvement rate in treatment group was significantly higher than that of control group after three and six weeks of treatment (100.0% vs. 42.4%, P < 0.001; 100.0% vs. 42.4%, chi2 = 19.352, P < 0.001). The disease-free rate at follow-up end-point in treatment group was significantly higher than that of control group (77.3% vs. 27.3%, chi2 = 13.239, P < 0.001). The effective rate at follow-up end-point in treatment group was also significantly higher than that of control group (100.0% vs. 36.4%, chi2 = 22.647, P < 0.001). The rate of HUT changing from positive to negative response between two groups after three weeks of treatment was not significantly different (31.8% vs. 12.1%, P > 0.05), but it was significantly different (81.0% vs. 48.5%, P < 0.05) after six weeks of treatment.</p><p><b>CONCLUSION</b>Selective alpha1 receptor agonist midodrine hydrochloride is effective in the treatment of children with postural orthostatic tachycardia syndrome.</p>

A multicenter study on treatment of autonomous nerve-mediated syncope in children with beta-receptor blocker / 中华儿科杂志

<p><b>OBJECTIVE</b>Syncope is a common pediatric emergency. Based on an epidemiologic survey in the USA, around 15% of children experienced syncopal attack, which strongly influenced the life, study and hurt the children mentally and physiologically. Therefore, exploring the therapeutic regimen has become a hot topic in the field of pediatric cardiology. The aim of this study was to examine the effect of beta receptor blocker in the treatment of children with autonomous nerve mediated syncope.</p><p><b>METHODS</b>Totally 103 children (43 males, 60 females, age 5 - 19 yrs, median 12.0 +/- 2.6 yrs) with autonomous nerve mediated syncope from Beijing, Hunan, Hubei and Shanghai, were included in this study. Forty-nine of them suffered from vasovagal syncope (VVS) and 54 suffered from postural tachycardia syndrome (POTS). They were randomly divided into treatment group accepting oral metoprolol treatment and control group accepting oral rehydration salt treatment. The frequency of syncopal episodes and the outcome of head-up tilt (HUT) test were observed. SPSS 10.0 software was used for the statistical analysis of these data.</p><p><b>RESULTS</b>The cure rate of children who suffered from VVS and POTS and took oral metoprolol was 60.61% and 68.75%, respectively, but in the control group, the cure rate was only 18.75% and 0.00%, respectively. The rate of improvement of children who suffered from VVS and POTS and were treated with oral metoprolol was 15.15% and 15.63%, respectively, and in the control group, it was 6.25% and 40.91%, respectively. The effective rates for cases of VVS and POTS treated with oral metoprolol were higher than those of cases received oral rehydration salt treatment (P < 0.01). The percentage of the change from positive HUT to negative for children with VVS and POTS who took oral metoprolol therapy was 60.61% and 68.75%, respectively, but in control group, it was only 18.75% and 9.09%, respectively (P < 0.01). There was a significant difference in the percentage of the change from positive HUT to negative between children with VVS treated with oral metoprolol and with oral rehydration salt (P < 0.01). Also, a significant difference was found in the percentage of the change from positive HUT to negative between children with POTS treated with oral metoprolol and with oral rehydration salt (P < 0.01).</p><p><b>CONCLUSION</b>beta receptor blocker is effective in the treatment of children with VVS or POTS.</p>

Etiologic and clinical characteristics of syncope in children / 中华儿科杂志

<p><b>OBJECTIVE</b>Syncope is a common problem in children and adolescents. Such an event may have multiple possible causes, ranging from benign conditions to life-threatening diseases. Syncope is a major challenge for the practicing physicians. It is very important to know the etiologic and clinical characteristics of syncope in children. This study aimed to improve diagnostic efficacy of syncope in children by analyzing the etiology and clinical characteristics of syncope.</p><p><b>METHODS</b>The investigators retrospectively analyzed the causes of syncope and diagnostic workup of 154 consecutive children seen in Department of Pediatrics, Peking University First Hospital because of a syncopal event.</p><p><b>RESULTS</b>Autonomic-mediated reflex syncope (AMS) was the most common cause of syncope (65.6%), whereas cardiac disorders were found in 10 cases (6.5%) comprising the second cause of syncope in children. Other causes included psychologic problems and neurological and metabolic disorders. Although many causes were studied, 25 cases (16.2%) were found to have uncertain etiologies yet. The children with AMS were commonly seen in pubertal girls, and they had clear inducement of syncope and prodromes. The children with cardiac syncope often had history of cardiac diseases, and they were often younger than those with AMS. Lack of prodromes of syncope, exercise-related syncope, syncope spells seen in any body position, frequent syncope spells and sudden death in family were clues of cardiac syncope. Neurological disorders should be considered if there are any of the followings: syncope with seizure activity, syncope spells seen in any position, and a postictal phase of disorientation or neurologic abnormal signs. A metabolic cause was entertained when the child had a history of metabolic diseases, prolonged anger, or violent vomiting and diarrhea. Children with psychiatric disorders were adolescent girls with prolonged syncope spells, and had more frequent syncopal episodes. Most children with syncope were evaluated by many of diagnostic tests, but most of those tests were not goal-directed approach. Since persons with cardiac syncope were at increased risk for death from any cause, electrocardiography was recommended in almost all children with syncope. Neurologic testing including electroencephalography, computed tomography, etc. were rarely helpful unless neurologic signs and symptoms are present. Holter electrocardiography and echocardiography were most useful in children with suspected cardiac syncope. There was little benefit of screening cardiac enzyme in children with syncope. Routine blood tests (blood electrolytes and blood glucose, etc) rarely yield diagnostically useful information unless the children had the history of metabolic diseases. Head-up tilt testing was most useful in children with recurrent syncope in whom heart disease was not suspected. The children with frequent syncope, long lasting syncopal episode and clear psychiatric inducement of syncope should be evaluated by psychiatric testing.</p><p><b>CONCLUSION</b>Syncope in children may result from a wide variety of causes, and clinicians often use a wide range of investigation to try to achieve a diagnosis. But most of investigations have low diagnostic yield. Thorough history taking, physical examination and electrocardiography are the core of the syncope workup.</p>

A multi-center study of hemodynamic characteristics exhibited by children with unexplained syncope / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Syncope is common in children and adolescents, with 15% estimated to have had at least one syncopal episode by age 18. In recent years, an increasing number of children, especially girls at their school age, have developed unexplained syncope. The mechanism of an unexplained syncope exhibited by children is incompletely studied; the association between different hemodynamic patterns and clinical features is also not clear. The aim of the study was to investigate the hemodynamic patterns of children with unexplained syncope and to examine the clinical relevance.</p><p><b>METHODS</b>Two hundred and eight children [87 boys, 121 girls, aged 3 - 19 years, mean (11.66 +/- 2.72) years] were selectively recruited from May 2000 to April 2006 when they presented syncope as their main complaint at the Multi-center Network for Childhood Syncope in Beijing, Hunan Province, Hubei Province, and Shanghai of China. All of the patients underwent head-up tilt tests; data were analyzed using SPSS version 10.0 for Windows. Continuous variables were expressed as the mean +/- standard deviation. Dichotomous variables were compared through a chi(2) test. A value of P < 0.05 (two sided) was regarded as statistically significant.</p><p><b>RESULTS</b>The age distribution of children with syncope was approximately normal. Head-up tilt tests was positive in 155 children, and the incidence of positive response of the baseline head-up tilt test for diagnosing unexplained syncope was 50.48%. The sensitivity value and diagnostic value of sublingual nitroglycerin head-up tilt test were both 74.52%. The hemodynamic pattern was normal in 53 children. The 155 children, who were positive in head-up tilt tests, showed signs of postural orthostatic tachycardia syndrome (60, 28.8%), the vasoinhibitory pattern (72, 34.6%), the cardioinhibitory pattern (5, 2.4%), and the mixed pattern (18, 8.7%). The gender distribution between the two age groups (age < 12 years vs age > or = 12 years) was not different (P > 0.05). The distribution of hemodynamic patterns between the children of the two age groups (age < 12 years vs age > or = 12 years), and the children with different complaints (dizziness vs syncope) was significantly different (P < 0.05), while the distribution between the children of different sexes and different lasting time of syncope (< or = 5 minutes vs > 5 minutes) was not significantly different (P > 0.05). Different hemodynamic patterns were differentiated by differing syncope inducements, presymptoms, and complicated symptoms during and after syncope.</p><p><b>CONCLUSION</b>The tested girls were more prone when compared with the boys to have unexplained syncope, and the peak age was around twelve years old. The incidence of positive response of head-up tilt tests was also relatively higher for the girls. The distribution of hemodynamic patterns for different ages was different. For children with unexplained syncope, we should use head-up tilttests to distinguish the hemodynamic patterns in order to adopt rational therapeutic measures.</p>

Change in plasma N-terminal pro-brain natriuretic peptide in children with Kawasaki disease and its value in clinical practice / 中华儿科杂志

<p><b>OBJECTIVE</b>Brain natriuretic peptide (BNP) is a cardiac hormone and its plasma level increases in congestive heart failure and myocarditis. An increased level of serum BNP has been reported in children in the acute stage of Kawasaki disease (KD). But the mechanism of increased level of BNP in children with KD has not been elucidated and the change in BNP in children with KD in China has not been reported. The aim of this study was to investigate the change in plasma N-terminal pro-brain natriuretic peptide (NT-pro BNP) in children with KD, examine the value of NT-pro BNP in the diagnosis of KD and explore the mechanism of the change in plasma NT-pro BNP in children with KD.</p><p><b>METHODS</b>Thirteen patients, aged from 4 months to 56 months, with KD were enrolled and nine patients with acute upper respiratory infection were used as controls. Blood sample was obtained to measure plasma NT-pro BNP concentrations in the acute (n = 13) and convalescent (n = 8) phases of KD and in the acute phase of the control patients. Plasma NT-pro BNP was measured using enzyme immunoassay. Other laboratory data including complete blood cell count, C-reactive protein, etc, were also measured in acute phase in both groups. The serum cardiac troponin I was also detected in acute phase of children with KD. All patients with KD had complete echocardiographic study, including measurement of left ventricular end diastolic diameter (LVDd), left ventricular ejection fraction (LVEF) and left ventricular inflow velocity through the mitral annulus (including E-velocity and A-velocity). Two dimensional echocardiography was performed to check for coronary lesions of patients with KD. The correlation between plasma NT-pro BNP and the above parameters was analyzed.</p><p><b>RESULTS</b>The mean plasma NT-pro BNP concentration in patients with KD in the acute phase was (691 +/- 86) ng/L, and it was (47 +/- 10) ng/L in patients of control group. The plasma NT-pro BNP in patients with KD in the acute phase was significantly higher than that of the control group (P < 0.001). In 8 cases of KD, the plasma NT-pro BNP concentrations were measured both in the acute and convalescent phase. The mean plasma NT-pro BNP concentration in the acute phase of KD was (636 +/- 89) ng/L and it was (164 +/- 35) ng/L in the convalescent phase. The level of plasma NT-pro BNP decreased significantly in the convalescent phase (P < 0.01). Through linear regression analysis, there was no significant correlation between the plasma concentrations of NT-pro BNP in acute phase of KD and LVEF, LVDd and E/A ratio, respectively. But the NT-pro BNP level correlated positively with C-reactive protein and white blood cells counts (r = 0.615, P < 0.05 and r = 0.547, P < 0.05), respectively. NT-pro BNP level correlated positively with serum cTnI, a sensitive biologic marker of cardiac injury (r = 0.611, P < 0.05).</p><p><b>CONCLUSION</b>The plasma NT-pro BNP concentration increased in the acute phase and decreased significantly in the convalescent phase of KD. The plasma NT-pro BNP might be one of the useful biological markers of KD, and the mechanism of change in plasma NT-pro BNP in KD might be associated with cardiac injury and inflammatory factors.</p>

Clinical analysis and follow-up study of postural orthostatic tachycardia syndrome in 28 pediatric cases / 中华儿科杂志

<p><b>OBJECTIVE</b>Lightheadedness, dizziness, chest discomfort, headache, pallor, palpitation, blurred vision, fatigue, and syncope are main symptoms of postural orthostatic tachycardia syndrome (POTS), but they are also common problems in clinical pediatrics. Besides, most of POTS cases have normal findings in routine examinations on cardiac and central nervous system. Therefore, they are often unable to be correctly diagnosed and treated in time. Since head-up tilt test (HUT) was introduced to diagnose unexplained syncope in children, it was discovered that the most common pattern of unexplained syncope in children was vasovagal syncope. But in the course of the investigation, we and other groups identified a large subgroup of patients who had a less severe form of orthostatic intolerance characterized by postural tachycardia, lightheadedness, dizziness, and chest discomfort, etc. This disorder has become generally known as the POTS, which in children is not rare, but its report was not seen in China so far. The aim of this article is to recognise the clinical pictures of POTS in children and to explore its diagnostic criteria and therapeutic protocol.</p><p><b>METHODS</b>All 28 pediatric patients of POTS who met the diagnostic criteria were selected to be the observation group. Age and sex distribution were observed, and the duration of symptoms, baseline heart rate and blood pressure were also recorded. The frequency of symptoms, the rate of misdiagnosis and the efficiency of therapeutic protocol were also analysed.</p><p><b>RESULTS</b>Twenty-eight patients were diagnosed as POTS, occupying 31.8% of all unexplained syncope or lightheadedness in children. Eleven were males and 17 females. The ratio of male to female was 1:1.5. All the 28 cases were from 6 to 16 years old, 5 of which were < 10 years and 23 were from 10 to 16 years old, including 10. The duration of symptoms of POTS in children was from 1 month to 6 years. The average was about 13 months, and more than one half were in 6 months. The most common orthostatic symptoms were lightheadedness or dizziness, syncope, chest discomfort, pallor and blurred vision associated with nausea and/or vomiting. During HUT or standing, an increase in heart rate > 35 beats per minute within 10 minutes was the most common finding, and some were associated with > 120 beats per minute within 10 minutes after HUT or standing up. The average time of the occurrence of abnormal responses was about 5 minutes. Especially, we found only 36% of patients were diagnosed with standing up test. Most of them were diagnosed with HUT. POTS in children was misdiagnosed as epilepsy or myocarditis in 43% patients. Multiple treatment protocol including health education and supportive, physical and medical therapy were most helpful in children with POTS.</p><p><b>CONCLUSION</b>POTS is commonly seen in school-aged girls. The common symptoms include dizziness, syncope and chest distress. HUT is an important tool in its diagnosis. A comprehensive therapeutic regimen is recommended in the treatment.</p>

Changes Hydrogen Sulfide in Plasma of Children with Congenital Heart Disease / 实用儿科临床杂志

Objective To investigate the changes of hydrogen sulfide (H_2S) level in plasma in order to explore the role of H_2S in the development of pulmonary hypertension (PH) secondary to congenital heart disease (CHD).Methods There were 9 CHD patients and 9 normal children in this study. The plasma concentration of H_2S and pulmonary artery pressure (PAP) of each child were measured. Meanwhile, the relationship between H_2S level and PAP was analyzed.Results The plasma level of H_2S in the group of CHD significantly decreased compared with control group (32.13?2.25) ?mol/L vs [(43.69?2.05)?mol/L, P

Head-up tilt testing potentiated with sublingual nitroglycerin for the diagnosis of unexplained syncope in children / 中华儿科杂志

<p><b>OBJECTIVE</b>Syncope is one of the common problems in clinical pediatrics. In recent years, vasovagal reflex was identified as the most common reason for unexplained syncope. Head-up tilt test (HUT) was regarded as one of the important diagnostic criteria. But the sensitivity of baseline head-up tilt test (BHUT) is low. To improve the sensitivity of HUT, we evaluated the diagnostic value of head-up tilt testing potentiated with sublingual nitroglycerin (SNHUT) in children with unexplained syncope.</p><p><b>METHODS</b>Twenty-five patients (11 male and 14 female, mean age 11.8 +/- 2.1 years, ranged from 8 to 15) with unexplained syncope and 10 healthy children in control group (5 male and 5 female, mean age 11.4 +/- 2.1 years, ranged from 9 to 15) were studied. The patients and healthy children were tilted upright to 60 degrees for 45 minutes at BHUT. If syncope did not occur, sublingual nitroglycerin (4 - 6 microg/kg, maximum dose 300 microg) was administered, and continued at same degree for 20 minutes.</p><p><b>RESULTS</b>Compared with controls, there was no significant difference in sex, age, supine blood pressure and supine heart rate of syncopal group (P > 0.05). During BHUT, 12 patients (48%) and none of the controls had positive response, whereas another 8 patients and 2 controls had positive response during SNHUT. In syncopal group, total positive rate was 80%. The sensitivity, specificity, and diagnostic value of SNHUT were all 80%. During SNHUT, the mean time to positive response was 5.9 +/- 2.9 minutes (from 4 to 11 minutes), and only 1 patient had mild headache.</p><p><b>CONCLUSION</b>Head - up tilt testing potentiated with sublingual nitroglycerin (4 - 6 microg/kg, maximum dose 300 microg) as pharmacological provocation test was a useful and an objective diagnostic tool for evaluating vasovagal syncope in children.</p>

Characteristics and Clinical Features of Positive Response for Head - Up Tilt Test in Children / 实用儿科临床杂志

Objective To study the characteristics and clinical features of positive response during head - up tilt test (HUT) in children. Methods Forty- nine cases of syncope and aura of syncope were included in the study. All of them underwent HUT (tilt angle 60 degree,lasting 45 minutes). During the test,children' blood pressure,heart rate.electrocardiography and clinical symptoms and signs were dynamically observed. Results The common syncope aura symptoms were headache, dizziness, chest distress, difficulties in breathing, pale, perspiration, blurred vision, auditus depression and symptoms related to digestive symptoms. Among the 28 positive cases, 7 cases were of vaso - inhibitory pattern (25%), with a decrease in blood pressure and an increase in heart rate, 3 cases inhibitory pattern (11%), with a decrease in heart rate but withoilt'blood pressure changes, 4 cases mixed pattern (14 %), with decreases in heart rate and blood pressure obviously, 10 eases POTS (36%), with an increase in heart rate by 30 bpm or up to 120 bpm within 10 minutes while testing, and 4 cases orthostatic hypotension (14%), with a decrease in blood pressure within 3 minutes. Conclusion HUT can be regarded as the main tool in differential diagnosis of unexplained syncope in children.

Effect of Metoprolol Treatment in Vasovagal Syncope in Children / 实用儿科临床杂志

Objective To explore the effect of the ?-blocker —metoprolol on the treatment of vasovagal syncope(VVS) in children.Methods Twenty-nine children with unexplained syncope and positive responses to head-up tilt test(HUT) were included in the study.Sixteen of them took metoprolol(treatment group) and 13 of them took vitamin B or oryzanol (control group) at least 2 weeks and HUT were repeated and syncope episodes were observed.Results In treatment group,9 of 16 patients had no syncope episode while 5 of 16 patients had fewer syncope episodes,1 case had more syncope episodes,and 1 case remained the same.HUT were repeated and 6 of 9 cases had negative outcome.In control group,1 of 13 patients had no syncope episode while 5 of 13 patients had fewer syncope episode,3 cases had more syncope episodes and 4 cases remained the same.HUT were repeated and 3 of 7 cases had ne-(gative) outcome.Conclusion These results indicate that adminstering metoprolol orally may be effective for VVS in children.

Diagnosis of Postural Orthostatic Tachycardia Syndrome in Children / 实用儿科临床杂志

Objective To discuss the clinical diagnostic method of postural orthostatic tachycarda syndrome(POTS) in children.Methods Thirty-six children with POTS were selected for the research.Among them 15 were boys,21 cases were girls.The age ranged from 5.9 to 16 years,average age 12.3 years.Among them 28 patients(78%) were in between 11-16 years.The age distribution,clinical courses and hemodynamic indexes were analyzed and also the incidence of clinical manifestations and investigation reports were observed.Results Among 81 patients of orthostatic regulation disturbance,36 patients were diagnosed POTS,which was 47% of total.The clinical courses ranged from 1 day to 5 years,average clinical course 10.2 months.The clinical courses of more than half of the total patients were within 6 months(56%).The common clinical features of POTS were chest tightness on standing,vertigo,fatigue,palpitation,syncope,orthostatic regulation disturbance.Ten patients were also associated with gastrointestinal symptoms like nausea,vomiting.The most common feature of POTS patients was tachycardia(HR increased by ≥30 times/min) within 10 min after head-up tilt test(HUT).Average HR increased by 38 times/min.In some patients HR increased up to ≥120 times/min.There were no significant changes in blood.In 23 cases(64%),the T waves were descended by ≥0.2 mV in 2 or more than 2 leads in ECG reading.Investigations reports showed that there were 12 cases whose urine specific gravity was increased.In 11 cases HCO_3~-decreased.Conclusions POTS is commonly seen in schooling female children.The common symptoms are vertigo,chest tightness,fatigue,palpitation.HUT is an important method for the diagnosis of POTS.