Low birth weight is a risk factor for poor outcome after surgery for congenital heart diseases.The estimated prevalence of low birth weight in Japanese neonates with congenital heart diseases ranges between 34% and 36%,indicating that the outcome of heart surgery in low-birth-weight infants significantly affects the overall outcome of congenital heart surgery in Japan.Although intentional delay of heart surgery because of low birth weight is reported to be unwarranted in the literature,approximately half of the infants with congenital heart diseases undergo delayed heart surgery with outcomes similar to that after early surgery.In the literature,corrective surgery,rather than palliative surgery,is recommended for low-birth-weight infants.On the other hand,hybrid procedures and percutaneous interventions are increasingly performed as valid options in infants with extreme low birth weight or co-morbidities.The timing and type of cardiac intervention in low-birth-weight infants should be individualized according to body weight,type of heart disease,and associated extracardiac diseases.

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The current status of pediatric drug approval and the problems of off-label drug use in Japan are described. Investigation reports published by the Pharmaceuticals and Medical Devices Agency(PMDA)showed that of the 740 drugs that had been approved from April 2001 to March 2012,154(20.8%)had pediatric indications. As short of medicines for children,we are obliged to prescribe off-label drugs in our daily practice. The most important problem of the off-label drug use is that we have to use drugs that have no description of adequate effect-efficacy for children. In addition,there are no clinical data concerning PK/PD and safety in children and the adequate dosage can not be determined. Furthermore,if a serious adverse event occurs in a patient treated with an off-label drug,the patient could not receive official relief aid by the PMDA. Another problem of off-label drug use is that no repayment could be applied to the medical institution in the health insurance system.
Clinical trials are indispensible to address these issues. However,clinical trials appear hard to perform in children. Another option to obtaining approval is filing an application based on the official notification describing procedures for approval of off-label drugs. This notification,published by the Ministry of Health,Labor,and Welfare in 1992 in order to approve offlabel drugs without a clinical trial,appears helpful in promoting pediatric indications for off-label drugs.

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Background: Outcomes of surgical repair of pulmonary atresia with intact ventricular septum(PAIVS)have improved with the adoption of appropriate approaches based on right ventricula(r RV)and coronary artery anatomy.Patients with a RV of adequate size and an RV independent coronary circulation have good surgical results after biventricular repai(r BVR).However,the long-term outcomes after BVR with regard to RV and left ventricula(r LV)function have not been clarified.
Objectives: To assess biventricular systolic function of PAIVS patients after BVR using cardiac MR(I cMR).
Methods: Four patients with PAIVS(P group)who were followed-up for more than 10 years after BVR in our institution were reviewed,and biventricular systolic function assessed by cMR was compared to that of the normal group(N group)who had no cardiac disease.
Results: Tricuspid valve diameter and right ventricular end-diastolic volume(RVEDV)at cardiac catheterization at birth and post-BVR increased from 73% ± 3.9%(mean ± SD)of the normal value to 88% ± 9.9% and from 45% ± 27% to 102% ± 49%,respectively.There were no significant differences in the RVEDV and LVEDV indices measured by cMR between the P and N groups,but the biventricular values of contractility were lower in the P group than in the N group(RV,P:N = 7.8 ± 3.7:16 ± 8.0,P = 0.06;LV,P:N = 36 ± 3.0:82 ± 49,P < 0.05).
Conclusions: PAIVS patients must be closely followed after BVR,because biventricular systolic function might be impaired even though biventricular volume may be comparable to normal.

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Background: Beta-blockers have recently become more commonly used for children with heart failure or arrhythmia.Alongside hypotension and bradycardia,hypoglycemia is a side effect of beta-blockers.Despite the potentially critical consequences of hypoglycemia,the risk factors for it resulting from beta-blzocker administration in children remain unclear.
Purpose: This study aimed to identify the risk factors for hypoglycemia as a result of the use of beta-blockers in children with Tetralogy of Fallo(t TOF).
Method: We reviewed the cases of 422 patients with TOF from 1983 through 2011 treated at our hospital.Patients were classified into 3 groups;received beta-blocker(s n = 214),received no beta-blocker(s n = 92),and with pulmonary atresia (n=116).Hypoglycemia was defined as a plasma glucose concentration of ≦40 mg/dL,or <50 mg/dl with Whipple?s triad.We analyzed the prevalence of hypoglycemia in each group and assessed factors contributing to hypoglycemia.
Results: Sixteen cases presented with hypoglycemia,all of whom received beta-blocke(r carteolol). Their mean plasma glucose was 26.4±14.1 mg/dL,mean age was 2.3±1.2 years,and mean Kaup index was 15.2±1.5.Most of the patients with hypoglycemia were on a restricted diet for cardiac catheterization or had inadequate feeding secondary to infectious disease.Hypoglycemia resulted in neurological sequelae in three cases,one of which resulted in death due to severe encephalopathy.
Conclusions: The findings indicated a relatively high incidence of hypoglycemia in infants with TOF treated with betablocker(s 7.5%),and the risk factors were inadequate feeding or starvation.Careful observation is essential for infants on beta-blockers under starving conditions.

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A pediatric cardiologist must be able to provide primary care for a patient with serious heart problems on the basis of quick diagnosis and then decide an appropriate therapeutic strategy in collaboration with cardiovascular surgeons.To provide young trainees with a good education and training,we divide our training program into 6 major categories:outpatient care,ECG,echocardiography,cardiac catheterization and intervention,intensive care,and adult congenital heart disease.For each topic of study and training,a stepwise goal must be set to acquire basic knowledge and technical skills in a fixed period of time.However,since department of pediatric cardiology in general hospitals are usually smaller than those of children's hospitals or university hospitals,we often challenged by an inadequate number of trained personnel.When adequate numbers of personnel cannot be obtained,the workload for individual trainee physicians tends to be excessive for adequate training.To overcome staff shortages and enlist new personnel,a deliberate and informative training program which makes trainees realize that they are making good progress is essential.It is also important to constantly attract future pediatric cardiologists to the department by maintaining reasonable patient volume,making presentations at annual conferences and so on.

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Neonatal myocarditis is a life-threatening condition with a poor prognosis,and may require extracorporeal membrane oxygenation( ECMO) for “rescue" therapy.We report successful balloon atrial septostomy( BAS),as an alternative therapy to ECMO,in a neonate with severe left ventricular dysfunction due to coxsackie B4 viral myocarditis.In this neonate,progressive deterioration of left heart failure with pulmonary edema and severe mitral regurgitation could not be controlled with medical therapy alone.The patient was judged to require ECMO support and transferred to our hospital.However,the parents disagreed the ECMO support.Because an echocardiogram showed that his ductus arteriosus was sufficiently patent to supply systemic blood flow,we performed BAS for “rescue" therapy on day 16 of life.Immediately after BAS,an echocardiogram showed that the left atrium was decompressed safely and systemic blood flow via ductus arteriosus increased adequately.Sequential echocardiograms showed gradual improvement of left ventricular function and mitral regurgitation following preload reduction of the left ventricle.His respiratory performance and hemodynamics improved dramatically.He was discharged without any significant sequelae at two months of age.Successful therapy with a combination of ECMO and BAS has been previously reported in a patient with severe left heart failure due to acute myocarditis.However,there have been no reports of successful therapy using BAS alone in patients with acute myocarditis.BAS may be a reasonable alternative therapy to ECMO for severe heart failure due to myocarditis under conditions of sufficient patent ductus arteriosus.

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