Techniques of cardiac re-synchronization therapy (CRT) for pediatric patients differs from those in patients with and without congenital heart defects. However, despite the use of CRT implants for pediatric patients based on the conventional method used in adults with medically refractory heart failure, specific ventricular morphologies need consideration when performing CRT in cases of complex congenital heart defects. Herein we introduce a novel method for managing CRT in infants, who not only have a small body size but also need individualized determination of pacing sites and surgical implantation methods, considering ventricular morphologies and the type of dyssynchrony in patients with complex congenital heart defects. For appropriate CRT in pediatric patients with severe heart failure, integration of further perspectives in this area are desirable.

In July 2010, the Japanese Organ Transplantation Act was revised. The revised act allowed organs from brain-dead donors younger than age 15 to be donated with the family’s consent. Since then, 6 years have passed and only 12 organ donations have been performed using organs from brain-dead donors younger than age 15. Six of the cases involved donors younger than age 6. Why has the rate of organ donation from brain-dead children not increased in Japan? Possible reasons include: presentation of the option of organ donation, exclusion of child abuse, establishment of facilities and an organizational system, premature pediatric terminal care, and burden on attending doctors. The most important step in overcoming these problems is, therefore, for Japanese pediatricians to change their approach. All pediatricians must take an active interest and participate in discussions on pediatric organ donation.

Since the Berlin Heart EXCOR were approved for pediatric patients in Japan, the condition of the patients while waiting for having heart transplant has become increasingly varied. Additionally, post-transplant patients still frequently require　medical follow-up and obey various restrictions in their daily life to prevent rejection. Therefore, medical professionals in the field of pediatric heart transplantation should be aware of the physical, emotional, and psychosocial impact of the experience of heart transplantation the experience of heart transplantation on both the patients and their families. As one of the members of the hospital multidisciplinary team, the Child Life Specialist (CLS) provides various psychosocial support to meet the children’s needs. Some examples of psychosocial support provided by the CLS include: 1) establishing developmentally appropriate and therapeutic play opportunities; 2) providing psychological preparation; 3) delivering distraction and pain management during procedures and examinations; 4) helping the children prepare for discharge and school re-integration; 5) offering sibling support and family care; and 6) contributing grief and loss support. Through these interventions, the CLS provides opportunities for children and their families to learn about heart transplantation and associated treatment, as well as express their feelings in therapeutic ways. This helps the children and their families to reduce their stress and anxiety regarding their medical experiences and enhance their ability to cope with difficulties in a hospital setting. Communication and collaboration with other professionals and families are essential for the CLS to provide such psychosocial support for pediatric patients. The CLS believes that this comprehensive psychosocial support has positive influence on the quality of life of these children.

The goals for the identification of arrhythmias using a 12-lead electrocardiogram (ECG) are as follows. The detection of a P-wave at 2 : 1 A–V conduction with an atrial flutter or atrial tachycardia is important. When confronted with a wide QRS tachycardia, it is necessary to determine if the arrhythmia is ventricular tachycardia or supraventricular tachycardia with ventricular conduction delay. The QRS morphology of a ventricular arrhythmia may allow for the site of origin to be determined, which is important information for catheter ablation. Even if there is no arrhythmia in a 12-lead ECG, the proarrhythmic factor can occasionally be identified. Inherited arrhythmias (e.g., LQTS, short QTS, and Brugada syndrome) can be diagnosed with a resting 12-lead ECG; however, in cases of catecholaminergic polymorphic ventricular tachycardia (CPVT), the resting 12-lead ECG is normal. Therefore, an exercise stress ECG and history of syncope are important for diagnosis. Cardiac diseases (e.g., cardiomyopathy) are also important bases of arrhythmia and we can observe abnormalities with a 12-lead ECG, even without an arrhythmia.

Several types of load tests for the diagnosis of arrhythmia (e.g., the exercise, pharmacological stress, orthostatic, and facial immersion tests) are introduced in this article, which are useful for deciding on the treatment. As these test are invasive, the careful selection of patients and obtaining adequate informed consent are important.

Arrhythmias extracted from school-based cardiovascular screening accounts for a large number of asymptomatic diseases, and there are many cases where it is difficult to manage them. In this article, we outline the premature ventricular contractions (PVCs), long QT syndrome (LQT), and WPW syndrome extracted from school-based cardiovascular screening. PVCs are a form of benign arrhythmia, many of which do not require drug treatment or intervention. Although a differential diagnosis of catecholamine-induced polymorphic ventricular tachycardia (CPVT) is problematic, CPVT does not often exhibit PVCs at rest, and it is rarely is CPVT detected by PVCs extracted by screening. LQT is examined by treadmill tests and Holter recordings. The Fridericia correction is recommended for the correction formula. If LQT is suspected, exercise limitations, preventive medication, and genetic testing should be considered. Although WPW is a disease caused by an accessory pathway connecting the atrium and ventricle diagnosed by a Δ wave, the distinction between a fasciculoventricular pathway (FVP) and WPW syndrome becomes problematic. FVPs are a disease free from the risk of tachycardias and sudden death and it is important to understand the concept of the disease.

Anatomical knowledge of atrioventricular valves is essential to enhance the quality of diagnosis and treatment of pediatric cardiac diseases. Basic structure and function of the mitral valve, which consists of two leaflets, annulus, chordae, and papillary muscles as well as their variations, should be properly recognized. In particular, dysplasia of the leaflets and abnormalities of subvalvar apparatus are frequently seen in congenital valvular diseases. Left circumflex coronary artery, coronary sinus, central fibrous body, and the aortic valve are located around the perimeter of the mitral valve. Basic structure of three leaflets, chordae, and papillary muscles of the tricuspid valve and its variations, which are occasionally seen in septal and anterior leaflets, should be recognized. Relationship to the aortic valve and the conduction system, including Koch’s triangle and membranous septum, are also important anatomical points. Atrioventricular septal defect and Ebstein’s anomaly are closely related to abnormalities of atrioventricular valves. Variations in common atrioventricular valve and anomalous location of the conduction system are particularly important for understanding atrioventricular septal defect. However, deformity and apical deviation of the septal and the posterior leaflets of the tricuspid valve, which may cause severe regurgitation, are pathognomonic in Ebstein’s anomaly. Accordingly, the right ventricle varies in size and shape. In single ventricle with univentricular physiology, durability of the tricuspid valve in systemic circulation and regurgitation of the common atrioventricular valve are important issues that may influence prognosis.

The function of the atrioventricular valve (AVV) has a great impact on the outcome of patients with congenital heart disease, especially those with single ventricular physiology. AVV regurgitation induces an elevation in atrial pressure, leading to an increase of both systemic and pulmonary venous pressure, and results in systemic and pulmonary congestion. There are three types of AVV: 1) mitral valve; 2) tricuspid valve; and 3) common AVV, all of which are morphologically very different. The AVV morphologies in patients with heterotaxy syndrome are extremely diversified, and thus are different from patient to patient. The function of the AVV is regulated not only by the valvar apparatus, but also by the subvalvar anatomy, ventricular, and atrial function. Although the precise preoperative anatomical assessment of the AVV still remains elusive, there are no other imaging modalities superior to echocardiography, including intraoperative transesophageal echocardiography or three-dimensional echocardiography. The tricuspid valve in patients with hypoplastic left heart syndrome or the common AVV with heterotaxy syndrome, are the most difficult AVVs to repair in single ventricles due to its complex anatomy. Thus, establishing the methodology for how to repair the AVV in this patient group would be a great contribution to prognostic improvement. Here an overview is presented on the usage of two-dimensional, three-dimensional, and transesophageal echocardiography to assess the anatomy of the AVV in pediatric patients.

Surgery for atrioventricular valve disease in infants and children has been a major therapeutic challenge for many years.

[Congenital mitral valve disease] It poses special clinical and technical difficulties that include a wide spectrum of morphologic abnormalities, high prevalence of associated cardiac anomalies, and small experience at each institute. Although conservative procedures may obviously be preferred procedures of choice, mitral valve replacement should be considered the procedure of choice in patients with severe deformities wherein conservative surgical treatment is unfeasible. Mitral valve replacement carries the disadvantage of requiring repeat valve replacement for relative prosthetic valve obstruction because of somatic growth.

[Atrioventricular septal defect] It is important to maintain or create two-competent, nonstenotic atrioventricular valves. Effective atrioventricular valve repair depends on adequate septation.

[Atrioventricular valve disease in patients with functional single ventricle] Surgery for patients with a functional single ventricle who have atrioventricular valve regurgitation remains a clinical challenge. Neonates or early infants who require surgical treatment of atrioventricular regurgitation still have poor outcomes. Although valve repair is preferable, prosthetic valve replacement should be considered when valve repair is questionable.

[Ebstein’s anomaly] Cone reconstruction of the tricuspid valve results in central blood flow through the tricuspid orifice and full coaptation of the leaflets. This technique can be performed with low mortality and morbidity. Early and long-term outcomes are favorable.

Background: We use autologous tissue (AT) for the posterior wall during repair of the right ventricular outflow tract (RVOTR) whenever possible during biventricular repair (BVR) in infants with pulmonary atresia with ventricular septal defect (PAVSD).

Methods: This study included 18 patients who underwent BVR for PAVSD by age 3 at our institute between 1996 and 2015. Patients were divided into groups of 12 and 6 who underwent RVOTR using AT as the posterior wall of the RVOT (Group A) and an expanded polytetrafluoroethylene conduit (Group C), respectively.

Results: Rates of freedom from reoperation and re-intervention tended to be higher in Group A than C (reoperation at 5 and 10 years, 72.7％ vs 62.5％ and 72.7％ vs 0％, respectively; re-intervention at 1 and 3 years, 63.6％ vs 50.0％ and 36.4％ vs 16.7％, respectively; p＝0.35 and p＝0.16, respectively; hazard ratio [HR], both 0.47). Postoperative pulmonary artery stenosis was treated by balloon dilation in Group A (10 times for 12 lesions) and Group C (10 times for 14 lesions). The ratio of right ventricular/left ventricular peak systolic pressure (RVP/LVP) did not significantly differ before and after treatment in both groups. The RVP/LVP significantly decreased among patients who did not undergo reoperation in Group A (6 times for 8 lesions; p＝0.001).

Conclusions: Applying RVOTR with AT as the posterior wall of the RVOT for BVR in infants with PAVSD may postpone the need for reoperation.

Background: Management strategies for congenital heart disease (CHD) associated with significant airway compression have not been standardized among institutions. The objective of our study was to determine the appropriate strategy and timing of treatment.

Methods: A retrospective review was conducted of 15 patients with tracheobronchomalacia caused by CHD who were treated from 2005 to 2015. Patients were classified into 3 groups according CHD type: I) absent pulmonary valve, II) left-to-right shunt anomaly, and III) vascular ring.

Result: Intracardiac repair (ICR) and division of the vascular ring improved respiratory symptoms in 9 (82％) of 11 patients. All 4 patients who did not undergo ICR died. Age at the time of surgery was I) 2.8±3.0, II) 6.0±3.4, and III) 7.8±3.9 months (mean±SD), respectively. The longest waiting period for surgery was reported for Group III (mean±SD 4.0±1.6 months). All patients in groups I and II required preoperative ventilation. Four (50％) of 8 patients with chromosomal abnormalities had poor symptom improvement.

Conclusions: ICR and division of the vascular ring were superior to palliative surgery for the relief of airway lesions. Surgical treatment might be required earlier in patients with CHD other than a vascular ring due to acute respiratory exacerbation. Early ICR should be considered in such patients.

There is a lack of information on the frequency, mechanism, and pathology of Fontan-associated liver disease (FALD). Liver congestion and ischemia associated with high central venous pressure are considered to be major causes of hepatopathy. We describe a male patient with shock liver in Fontan circulation, protein-losing gastroenteropathy (PLE), and a portosystemic shunt (PSS), all accompanied by conjugated hyperbilirubinemia after hospitalization for PLE. Despite intensive care, the patient died of liver failure. Autopsy findings revealed cholestasis in bile capillaries, dilated central veins and sinusoids, and necrotic centrilobular hepatocytes. These histological features suggested that shock liver caused hepatic failure. We speculated that PSS decreased blood flow in the portal vein, inadequate hepatic circulation became progressively pronounced in a low-output state associated with heart failure, and this was followed by shock liver. The primary etiology of FALD is described as hepatic fibrosis, but shock liver should also be considered in the potential etiology of FALD. More information from similar patients needs to be accumulated for developing effective treatment strategies.