Cardiac catheterization of childhood pulmonary arterial hypertension (PAH) plays a pivotal role in the assessment of severity of the disease, prognosis, selection of the most adequate pulmonary vasodilators, and evaluation of effectiveness. However, sudden deterioration of cardiovascular hemodynamics can be easily induced by pain, patientʼs agitation, catheter manipulation, and by vasodilator provocation tests, which could evoke a pulmonary hypertension crisis, vagotony, respiratory distress, and hemoptysis resulting in critical complications, including death. Those patients with NYHA functional class 4 are especially at high-risk. It is noteworthy that pulmonary arteriography is a contraindication in patients with PAH.In a review of 7,218 adult patients, 76 (1.1%) serious complications, including 4 deaths, were reported; as for pediatric population, 29 cases (10.7%) out of 270 patients, including one with cardiogenic shock requiring cardiopulmonary resuscitation in addition to minor complications, were reported.For prevention of serious complications, basic and routine precautions such as oxygen administration and concomitant monitoring of SpO₂, as well as ECG during transportation to and from the catheter laboratory, are mandatory. Furthermore, the cooperation of experienced physicians and well informed co-medicals in addition to meticulous preparation, e.g. prior doses calculation of catecholamine and confirmation of the presence of emergency equipment, are required.

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Since the heart screening for school children has been established in Japan, majority of the heart diseases in school children is now well controlled and the total number of sudden cardiac death has been decreased. The first step of the screening consists of questionnaire of heart disease, physical examination by school doctors, and electrocardiography. Children with history of heart disease such as Kawasaki disease, rheumatic fever, hypertension, arrhythmia, syncope, or abnormal findings in the first step, are referred to the second step. The second step includes physical examination by pediatric cardiologists, and if necessary, electrocardiography, chest X-p, echocardiography, and exercise stress tests. Children who need further medical management or treatment are referred to the hospitals, i.e., the third step. Their exercise tolerance and school lifestyle are properly controlled with the table of management criteria for children with heart disease.

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Background: Many pediatric patients with ASD have neither clinical symptoms nor specific findings on ECG. We studied to determine the prevalence of the crochetage pattern and clarify the clinical significance of this finding in the pediatric patients with ASD.
Methods and Patients: We analyzed the ECGs obtained from 151 preoperative pediatric patients with ASD. These ECGs were compared with 339 non-ASD control patients. The crochetage pattern was defined as notch on the R wave in inferior limb leads. We determined the sensitivity and specificity of the crochetage pattern and investigated the correlation between the prevalence of the crochetage pattern and the severity of Qp/Qs.
Results: The sensitivity and specificity of the crochetage pattern in all three inferior limb leads were 11.3％ and 100％ with all control groups combined. The prevalence of the crochetage pattern was high, especially in older group (≥ 10 years old). In hemodynamic study, the prevalence of the crochetage pattern in the patients with Qp/Qs ＞ 3.0 was higher than with Qp/Qs ≤ 1.5 (p ＝ 0.003).
Conclusion: The specificity was remarkably high when the crochetage pattern presented in all three inferior limb leads in the patients with ASD. In addition, the prevalence of the crochetage pattern was high when the patients had severe grade of left-toright shunt and reached the old age group. Therefore, we thought the crochetage pattern could be the useful tool for the electrocardiographic diagnosis of ASD in the childhood.

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Background: Sildenafil, a phosphodiesterase-5 inhibitor, has been widely used as an effective selective pulmonary vasodilator in the treatment of severe pulmonary hypertension (PH) after congenital cardiac surgery. We explored a new active administration of SIL and assessed its beneficial effects on clinical course and pharmacoeconomics in this comparative cohort.
Methods: Sildenafil was administered at a starting dose of 0.5 mg /kg in the intensive care unit and the dose was increased stepwise to a maximum of 2 mg/kg/every 4 hours. We made a comparison of the two groups; group C (conventional administration) where sildenafil was started via nasogastric tube in the withdrawal from inhaled nitric oxide (iNO) (N=13), and group A (active administration) where SIL was started immediately after the ICU admission by enema (N=13). There were no significant differences in the preoperative patient background between the two groups.
Results: Pulmonary arterial pressure significantly decreased in both groups (p<0.05) with similar degrees of change. Five patients in group C required iNO to treat severe PH crises while none in group A experienced similar symptoms. The duration of mechanical ventilation and ICU stay was significantly reduced in group A compared with group C (p<0.05). Medical costs relating to acute management in ICU and the whole hospital stay were significantly higher in group C than in group A.
Conclusion: Active use of SIL can be a favorable option not only for treatment but also for substantial cost savings to treat persistent PH early after pediatric congenital cardiac surgery.

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Background: Patients with asplenia are at an increased risk for bacterial infections and are especially susceptible to Streptococcus pneumoniae infections, which sometimes lead to fatal consequences. In 2010, 7-valent pneumococcal conjugate vaccine was introduced in Japan, and it was expected to have protective effects against S. pneumoniae infections.
Method: We retrospectively investigated the clinical course of 7 patients with asplenia syndrome who had a serious bacterial infection (meningitis/sepsis) in the era before 7-valent pneumococcal conjugate vaccine was available.
Results: Serious bacterial infections were identified in 7 out of 44 (16%) patients with asplenia syndrome. The age range at the bacterial infection onset varied between 3 months to 4 years, and 5 out of 7 patients were at <2 years of age. Initial symptoms were non-specific in all patients that included fever, ill humor, and poor appetite. However, the patientʼs health deteriorated rapidly, and symptoms at admission entailed cardiopulmonary arrest, shock, and unconsciousness. The mortality rate was 57%.Streptococcus pneumoniae was the pathogen responsible for the infection in 5 out of 7 (71%) patients. Some of these patients could have been protected against the infection if they had been inoculated with 7-valent pneumococcal conjugate vaccine.
Conclusion: Serious bacterial infection (meningitis/sepsis) in patients with asplenia syndrome is associated with rapid health deterioration and a high mortality rate. Early diagnosis is difficult in these cases, and the education of all medical staff andpatient families is essential. Patients with asplenia syndrome should receive the 7-valent pneumococcal conjugate vaccine as soon as possible.

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Background: The Ghent nosology for Marfan syndrome was revised in 2010. It puts more weight on aortic root aneurysm, ectopia lentis and fibrillin-1 (FBN1) mutation. Skeletal findings on the old Ghent nosology are given less weight and the findings are defined as the systemic score.
Methods: We compared the old and revised Ghent nosology in Japanese pediatric patients with suspected Marfan syndrome. We enrolled 38 pediatric patients with diagnosed or suspected Marfan syndrome based on the old Ghent criteria, and the patients were followed at the University of Tokyo Hospital from April 2008 to December 2009.
Results: Thirteen patients fulfilled the criteria of the old Ghent nosology and twenty-two fulfilled the criteria of the revised nosology (p=0.0039). Of 22 patients fulfilled the revised nosology, seventeen patients had family histories (77%), ten had aortic root aneurysms (45%), ten had ectopia lentis (45%), and FBN1 mutation were detected in 2 out of 3 analyzed samples (67%). On the other hand, only 4 patients (18%) had enough systemic score points to fulfill the new criteria.
Conclusion: This revised nosology is easier to apply to children. Moreover, with the spread of FBN1 mutation analyses, improvement in diagnostic accuracy and an increase in the diagnosis of Marfan syndrome will be expected.

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Background: Double aortic arch (DAA), a typical vascular ring, causes dyspnea and dysphasia, regardless of whether DAA is complete or incomplete (atretic arch of one side remaining as a ligament). We report clinical findings on diagnostic imaging and the perioperative course in our cases of DAA.
Method and Results: We retrospectively studied 11 patients with DAA (6 males and 5 females) between July 1975 and September 2012. Their ages ranged from 3 months to 9 years, excluding 2 fetuses.
Results：Complete DAA was diagnosed in 4 patients, and incomplete DAA was diagnosed in 7. Respiratory symptoms were present in all patients, excluding the 2 fetuses, and dysphasia was present in only 1 patient. Contrast-enhanced computed tomography and three-dimensional reconstruction imaging showed posterior and inferior distortion of the subclavian artery due to traction by an atretic arch and Kommerell diverticulum in all patients with incomplete DAA. Percent diameter tracheal stenosis (the tracheal diameter of the narrowest part divided with the one of the widest part) was measured by computed tomography images in 4 patients of the 10 operative patients. The average of percent diameter tracheal stenosis in the operation group was 48％ and a result of 59％ was recorded in one observation patient. In all of 3 patients with lower than 50％ , the symptoms worsened while waiting for operation； on the other hand, their symptoms did not worsen in 2 with the percentage higher than 50％ , and one of them has been followed up without operation. Ten patients received operation at a median age of 2 years 3 months. Respiratory symptoms improved in all patients, but mild symptoms persisted in 3 who were observed after operation for one year or shorter and 2 of 7 observed longer than one year.
Conclusion: The contrast-enhanced computed tomography and three-dimensional reconstruction imaging are useful for diagnosis of iDAA. Early surgery is desirable for patients with severe stenosis of trachea, because symptoms may worsen while waiting for operation. All patients improved after operation, but some had persistent mild symptoms, and thus long-term observation is necessary.

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Background: Non-high-density lipoprotein cholesterol (non-HDL-C) is now recognized as strongly predictive of cardiovascular disease in adults, and was recommended as the secondary lipid management goal in Japanese atherosclerosis society guidelines for the diagnosis and prevention of atherosclerotic cardiovascular disease. However, there have only been a few reports about that in children.
Methods: 5,853 fourth and seventh grade schoolchildren were included in the screening for lifestyle-related disease from 2010 to 2011 in Takaoka City, and received anthropometric measurements and blood tests for total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), triglycerides (TG), and low-density lipoprotein cholesterol (LDL-C) levels. The relationship between the percentage overweight (POW) values and the levels of each lipid was analyzed, and children above the 97th percentile of levels of TC (220mg/dl) and non-HDL-C (152mg/dl) were closely compared and assessed. Among the reexamined 150 obese children, the relationship between the prevalence of metabolic syndrome and non-HDL-C levels was analyzed.
Results: Non-HDL-C was positively correlated with POW and TG more so than TC (r = 0.273, 0.360 vs. 0.118, 0.179, all P < 0.001). In the screening for TC, several subjects with high HDL-C subjects were incorrectly categorized. Consequently, the sensitivity of identifying high LDL-C subjects was lower using TC levels than non-HDL-C levels for screening (80.8% vs.98.3%). The prevalence of metabolic syndrome increased significantly when non-HDL-C levels were elevated in re-examined obese children (P = 0.009).
Conclusion: Non-HDL-C levels rather than TC levels will serve as a better screening tool for lifestyle-related disease in schoolchildren.

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Congenital long QT syndrome (LQTS) after birth was diagnosed in a boy noted to have a 2:1 atrioventricular block during the fetal period. Medication with mexiletine hydrochloride was started, but loss of consciousness and rigidity of limbs occurred during napping. At the first clinical ventricular fibrillation (VF), cardiopulmonary resuscitation (CPR) was immediately initiated, and his heart rhythm was restored by electrical defibrillation by emergency services. Although he recovered without severe neurological sequelae, Torsade de pointes subsequently occurred and an implantable cardiac defibrillator (ICD) was implanted. LQT3 by genetic analysis was diagnosed at a later date. A strategy for ICD implantation in infants has not been established because few progress reports have been published. In infants, implantation of the epicardial leads through a lateral thoracotomy is common because indwelling of the transvenous endocardial leads is not possible. However, heart failure due to diastolic dysfunction and difficulty in lead removal resulting from adhesion are concerns. Therefore, we considered application of cardiac defibrillation between the ICD generator under the rectus abdominis muscle and the transvenous endocardial lead as a shock cord placed in the subcutaneous tissue of the back. Cardiac defibrillation for sustained VF was applied appropriately five times during five years after implantation without any complications, although the ICD generator required one exchange due to battery loss. We conclude that ICD implantation is safe and very useful, and strongly recommend ICD implantation for high risk LQTS patients with histories of VF and CPR, even at infancy.

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A boy with asplenia syndrome and functional single ventricle experienced complications of right hemidiaphragmatic paralysis when undergoing the bidirectional Glenn procedure at 10 months of age. Cardiac catheterization revealed steal phenomenon of the upper systemic blood flow through the hemiazygos vein to the lower. After diaphragm plication at 1 year and 11 months of age, pulmonary hemodynamics was reassessed under balloon occlusion of the hemiazygos vein. Right, left, and total pulmonary vascular resistance was 7.84, 3.89, and 2.60 Wood units・m², respectively. Though imbalanced in the laterality of pulmonary circulation, the Fontan procedure was considered as applicable to the patient. Total cavopulmonary connection (TCPC) and replication of the diaphragm were performed at 2 years and 10 months of age. Cardiac catheterization 7 months after the operation showed low mean pulmonary pressure (11 mmHg), low total pulmonary vascular resistance (2.04 Wood units・m²), and high enough cardiac index (3.64 L/min/m²), and the patient seemed to have a good Fontan physiology from the uneventful postoperative clinical course. The laterality of pulmonary circulation, however, remained imbalanced (right and left pulmonary resistance was 5.69 and 3.20 Wood units・m², respectively). Diaphragmatic paralysis is a risk factor to deteriorate Fontan circulation because diaphragmatic function is very important in Fontan physiology, which lacks the ventricular driving force for pulmonary blood flow. This case presented an imbalance in the laterality of pulmonary circulation that existed even after diaphragm plication, which suggested the need for further careful follow-up for the so-called failing Fontan physiology.

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