Hypertrophic cardiomyopathy(HCM)is an inherited cardiomyopathy characterized by left ventricular hypertrophy without ventricular enlargement,which is one of the main causes of athletic sudden death in adolescents. Early detection of symptoms and timely diagnosis and treatment are of great value in preventing athletic sudden death and improving the prognosis. The diagnosis of HCM is based on medical history,physical examination and echocardiography,as well as family history and genetic testing in recent years. In recent years,cardiac magnetic resonance(CMR)and CT examination have become more and more important in the diagnosis of HCM. The aim of the article is to explore the characteristics of CMR and CT in the diagnosis of HCM.

Hypertrophic cardiomyopathy(HCM)is one of the leading causes of sudden cardiac death(SCD)in children and young adults. The incidence of HCM in adults is 1/500,which is mainly coding sarcomere-associated protein gene mutations. The most common are MYH7 and MYBPC3. The incidence of HCM in children is unclear,and the etiology is more complicated. The clinical manifestations are highly heterogeneous. There are many kinds of non-sarcomere mutations,including metabolic storage diseases,RASopathies,neurodegenerative diseases and mitochondrial diseases. Up to now,more than 40 genes are associated with pediatric HCM. Multiple modes of inheritance account for HCM,among which autosomal dominant inheritance is the most common mode. Others include autosomal recessive,X-linked,and mitochondrial inheritance.

Hypertrophic cardiomyopathy(HCM)is mainly hereditary heart disease caused by gene mutation encoding cardiac sarcomere protein. HCM is the main cause of sudden cardiac death in athletes and adolescents. The clinical manifestations of HCM in children are complex and varied,including being asymptomatic,exercise intolerance,syncope,and sudden death,etc. Labor dyspnea and chest pain are the most common symptoms in older children. The diagnosis of HCM in children is mainly based on imaging examination,which can be divided clinically into three types:obstructive,non-obstructive and occult obstructive. Risk factors were assessed according to the patient's age,clinical symptoms,imaging findings and family history to guide further treatment,management and prognosis.Drug therapy mainly includes beta blockers,non-dihydropyridine calcium antagonists and other anti-arrhythmic drugs,as well as anticoagulants,diuretics and other applications. For those who are not satisfied with the effect of drug treatment,implantable cardioverter defibrillator(ICD)or surgical treatment can be used. In recent years,with the development of gene detection,the diagnosis of HCM in children is more refined and the treatment is accurate.

Hypertrophic cardiomyopathy(HCM)is the second commonest form of heart muscle disease affecting children and adolescents and is a leading cause of sudden death in young athletes. The aetiology of HCM is heterogeneous in the paediatric population,and includes inborn errors of metabolism,neuromuscular disorders and malformation syndromes.However,most cases of apparently idiopathic HCM in childhood are caused by mutations in cardiac sarcomere protein genes. Hypertrophic obstructive cardiomyopathy(HOCM) is not uncommon in children who don't respond to drug treatment;for such children,surgical treatment is the only solution.Previous routine surgical methods include modified Konno operation,modified extended Morrow operation and interventional alcohol ablation or radiofrequency ablation for pediatric patients. At present,the reports and large-scale clinical experience are rare.

Hypertrophic cardiomyopathy(HCM)is a common cause of sudden deaths in children and adolescents,mostly due to ventricular arrhythmia. The abnormal ECG activity of HCM is related to the histological characteristics of myocardial hypertrophy. Although ECG lacks specificity,some changes still have certain sensitivity in HCM,or give hints to potential causes. These can provide valuable basis for the early diagnosis,as well as the monitoring and management of high-risk patients,and help estimate the time of ICD treatment.

Hypertrophic cardiomyopathy(HCM) is defined by the presence of increased left ventricular(LV)wall thickness that is not solely explained by abnormal loading conditions. It includes familial HCM caused by mutations in the genes encoding the cardiac muscle branch contraction-associated protein,as well as hereditary HCM caused by mutations in genes encoding non-muscle-contracting system-associated proteins. Malformation syndromes are symptom complex characterized by multi-system and multi-organ abnormality. HCM can be the only or major manifestation of its cardiovascular system lesions. The article will briefly introduce HCM associated with malformation syndrome in children.

Inborn errors of metabolism in children is an important cause of hypertrophic cardiomyopathy. Characteristic manifestations of the diseases are helpful for rapid diagnosis. Most of the diseases are autosomal recessive inheritance,a few of them are autosomal dominant inheritance,X-linked inheritance,while some mitochondrial diseases are maternal inheritance. Conventional cardiac examinations such as electrocardiogram and echocardiography can provide diagnostic clues for the underlying causes of some diseases. With the rapid progress of new treatment methods such as enzyme replacement therapy,strengthening cardiac assessment,appropriate treatment for underlying diseases and multi-disciplinaries collaboration will provide more opportunities of survival for the patients.

Mitochondrial disease is a heterogeneous group of hereditary diseases caused by the defects in the mitochondrial respiratory chain and abnormal cellular energy metabolism.Heart is one of the most common organs involved,and hypertrophic cardiomyopathy is the most common and important type of cardiac involvement in mitochondrial disease. Hypertrophic cardiomyopathy in the patients with mitochondrial disease with childhood onset is more common than those with adulthood onset. Mortality in children with cardiac involvement caused by mitochondrial disease is significantly higher than that in children without cardiac involvement,so the early diagnosis and treatment is very important. But the early diagnosis is still difficult due to the complexity of clinical manifestations of mitochondrial disease. There is no specific treatment for mitochondrial disease and its associated hypertrophic cardiomyopathy,so supportive therapy is still the main treatment.

OBJECTIVE: To investigate the efficacy and safety of propofol used as anesthesia and deep sedation during flexible bronchoscopy in children. METHODS: The clinical data of 206 children with atelectasis who underwent flexible bronchoscopic alveolar lavage in the Endoscopy Room of the Respiratory Department of Hebei Children's Hospital from January 2016 to January 2017 were retrospectively analyzed. Children for ASAⅠ/Ⅱ level were divided into two groups according to the sedation method :there were 106 cases in the propofol group(2 mg/kg)and 100 cases in the midazolam group(0.1 mg/kg).To compare the onset time of anesthetict,heart rate(HR),respiratory rate(RR),mean arterial pressure(MAP),percutaneous oxygen saturation(SPO2)before and after anesthesia induction(T0,T1),during endoscopy placement(T2)and after awakening(T3)at 4 time points,operative duration,the waked duration of postoperation,the rate of adverse reactions(hiccups,respiratory depression)in the operation and Ramsay score between two groups. All data were analyzed by SPSS 20.0 statistical software.RESULTS:(1)There were statistically significant differences at the onset time of anestheticts,operative duration and the rate of side-effects between the two groups(P<0.05). There was no statistical differences in awake time(P>0.05).(2)There was no significant difference in MAP or SPO2 at time points of T0,T1,T2,T3(P>0.05),whereas the difference in HR and RR at time points of T1,T2,T3 between the two groups was statistically significant(P<0.05).(3)The sedative effect of propofol group was significantly better than that of midazolam group in Ramsay sedative scoring. CONCLUSION: Propofol used for anesthesia and deep sedation works fast,safely and effectively in flexible bronchoscopy for children;the time to gain consciousness is short,the operation time is short and there is fewer side effects,which is worth promoting.

OBJECTIVE: To explore the effects and results of temporary cardiac pacing in children with bradyarrhythmia.METHODS: The clinical data of 55 children with bradyarrhythmia who received temporary cardiac pacing between June2007 and May 2018 in Children's Hospital of Chongqing Medical University were analyzed retrospectively. The clinical characteristics and curative effects were summarized and statistically analyzed. RESULTS: A total of 55 cases of bradyarrhythmia included 29 cases of severe atrioventricular block(AVB),sinus bradycardia or cardiac arrest caused by myocarditis,5 cases of Ⅲ°AVB or sick sinus syndrome caused by cardiomyopathy,6 cases of Ⅲ°AVB caused by congenital heart disease after surgery,5 cases of congenital Ⅲ°AVB,and 10 cases of perioperative temporary pacing Ⅲ°AVB.Among them,39 cases were compared in Adams-Stokes syndrome(P=0.003),34 cases were compared in ejection fraction and fractional shortening(P=0.000,P=0.001),and 26 patients were compared in left ventricular end diastolic diameter(P=0.001)before and after temporary pacing,and there were statistically differences. After treatment,18 cases were clinically cured,36 cases were improved,and 1 case died,among which 45% arrhythmia were improved or recovered,and 10 cases of perioperative children all passed through the anesthesia period. Kruskal-Wallis H(K)test showed that the clinical and arrhythmia prognosis of different basic cardiovascular diseases were not completely the same(P=0.001,P=0.000);Mann-Whitney U test indicated a better prognosis in the myocarditis group(P=0.001,P=0.000).CONCLUSION: Temporary cardiac pacing can effectively relieve the clinical symptoms of severe bradyarrhythmia caused by various etiologies,promote the recovery of acute conduction system injury,and reduce Ⅲ°AVB perioperative risk.Temporary cardiac pacing is a safe and effective prevention and first-aid technique.