Trisomy 18 (T18) and trisomy 13 (T13) are among the most prevalent autosomal aneuploidies causing severe delay of psychomotor development, congenital heart defects, and other multiple congenital anomalies. Aggressive therapies for patients with either trisomies are not recommended because these diseases are associated with a very high risk of mortality. Recently, some investigators have reported that intensive medical management can extend the life-span of patients with T18 or T13, and some population-based studies have demonstrated a longer survival rate by 5 to 10 years. The characteristics of congenital heart defects in patients with T18 or T13, such as pulmonary vascular obstructive disease, which progresses rapidly in some individuals, are gradually being recognized. However, there are many problems associated with cardiovascular surgery that should first be considered, such as appropriate timing and procedures as well as associated anomalies of other organs. To date, it is not yet clear whether cardiovascular surgery can improve the long-term prognosis of patients with these trisomies. Therefore, cardiovascular surgeries are performed at some institutions but are not even considered at the others. The aim of surgery is not only to prolong the life-span of patients but also to improve the quality of life of the patients and their families. When deciding on medical management strategies, it is essential to provide evidence-based and precise information to families of patients and to consider the best interest of the child and wishes of their families.

Exercise intolerance is one of the major symptoms of chronic heart failure. Cardiopulmonary exercise testing (CPX) allows for the simultaneous study of responses to cardiovascular and ventilator systems to a known exercise stress through the measurement of gas exchange at the airway. During exercise, oxygen consumption and carbon dioxide production at the contracting muscle are coupled with the external respiration at the lung through the cardiovascular system. Therefore, by studying external respiration in response to exercise, it is possible to address the functional competence of the cardiovascular system to meet the increased cellular respiratory demands during exercise. Objective assessment of exercise intolerance by means of CPX is especially important in patients with congenital heart disease (CHD), as they have made lifelong adaptations to their cardiovascular disease and its slow progression. Thus, they are not aware of the true extent of their exercise intolerance. Moreover, recent studies have demonstrated the ability of several CPX parameters to predict the long-term survival of patients with CHD. Because CHD patients often require high-risk surgical or catheter interventions and risk stratification based on individual risks is essential in this population, CPX plays a major role in the management of CHD. On the other hand, there are several pitfalls in interpreting the results of CPX in CHD. This review provides an overview of the interpretation and application of CPX in CHD.

Since percutaneous balloon pulmonary valvuloplasty for pulmonary valve stenosis (PS) was first successfully performed using a ureteral catheter in 1950s, BPV has become standard of care for treatment of isolated PS over surgical valvotomy. Based on the experience, percutaneous pulmonary valve implantation (PPVI) was performed by Bonhoeffer et al. in patient with a dysfunctional of right ventricle-to-pulmonary artery conduit. In 2010, the Melody valve (Medtronic, Minneapolis, MN) became commercially available in the United States (US) under a humanitarian device exemption protocol, and more recently, was awarded post market approval by the US Food and Drug Administration. Since then, PPVI has been performed for over 4,500 patients in more than 30 countries worldwide. Transcatheter aortic valve replacement (TAVR) has recently became the standard therapy in patients with aortic stensis, and based on this technology, transcatheter pulmonary valve replacement (TPVR) and valve-in-valve procedure has also been able to be performed in patients with adult congenital heart disease. In conformity with heart team approach, hybrid procedures with mutual collaboration from cardiac surgery and interventional cardiology will likely shape the future TPVR. In this chapter, we will review BPV and PPVI/TPVR with particular focus on the indication, technical aspect, clinical outcomes, and potential complications.

Bis-diamine was administered at a dose of 200 mg to 40 pregnant rats on the 9th and 10th days of gestation. Following cervical dislocation of these rats on the 21st day of gestation, the fetuses were delivered by cesarean section and then frozen immediately in acetone cooled to −76°C with dry ice. The thorax of each frozen fetus was cut transversely, and the section surface was serially photographed using a stereoscopic microscope (Wild M400 Photomacroscope) at every 500 µm. Among 300 fetuses, congenital heart disease (90％), thymic hypoplasia (100％), and diaphragmatic hernia (40％) were identified. In the 120 fetuses with diaphragmatic hernia, pulmonary and cardiac hypoplasias were recorded as follows. The liver and stomach occupied the left thorax; the heart deviated to the right and was hypoplastic. The left lung was hypoplastic as a result of the invasion of the liver and stomach into the left hemithorax. In cases with the most severe hernia, the liver and stomach occupied the total left hemithorax, resulting in minimal residual left lung. The right lung was also hypoplastic due to a rightward shift of the cardiac and mediastinal structures. In mild cases, only a small portion of the liver invaded the left posterior hemithorax, with mild hypoplasia of the left lung, normal right lung, and near-normal heart structures. These pictures clearly show the variability in cardiopulmonary hypoplasia due to the invading abdominal organs into the left hemithorax.

Background: Surgical intervention for asymptomatic aortic regurgitation (aAR) should be performed while the left ventricular (LV) functional reserve is maintained. However, data on the optimal timing for surgery in pediatric patients with aAR are scarce. Therefore, this study aimed to clarify the optimal timing for surgical intervention in patients with aAR in consideration of the LV functional reserve.

Methods: Thirty-three patients with aAR who were ＜18 years old and underwent aortic valve repair at Shizuoka Children’s Hospital were enrolled. We retrospectively examined their medical charts and echocardiography records.

Results: For patients in whom the preoperative echocardiographic assessment of LV geometry showed either an indexed left ventricular end-systolic dimension (ESDI) of ＜31 mm/m² or an indexed end-diastolic dimension (EDDI) of ＜51 mm/m², LV dimension improved to the normal range (ESDI ＜25 mm/m² and EDDI ＜40 mm/m²) at 3 years after surgery while maintaining an LV ejection fraction (EF) of ≥50％ in 80％ and 77％ of the patients, respectively. Hazard ratios for not recovering to the normal LV geometry or EF after the surgery were as follows: preoperative ESDI ≥31 mm/m²: 1.60 (95％ confident interval [CI]: 0.6–4.3, p＝0.3), preoperative EDDI ≥51 mm/m²: 1.96 (95％ CI: 0.6–5.2, p＝0.3), preoperative EF ＜50％: 3.37 (95％ CI: 0.8–14.6, p＝0.1). Death and aortic valve reoperation were not noted during the observation period.

Conclusion: An ESDI of ≥31 mm/m² or EDDI ≥51 mm/m² can be useful indicators for determining the optimal timing for surgical intervention in patients with aAR who are younger than 18 years.

Background: The number of medical consultations for severe heart failure in pediatric patients has been increasing in all regions in Japan. As a result, high-risk interhospital transport is becoming a more challenging task.

Methods: Forty-two pediatric patients with severe heart failure who were transferred to our hospital between July 2010 and December 2018 were reviewed. We investigated patient characteristics, type of transport, and outcomes after transportation, including implantation of a ventricular assist device. We also discuss practical issues of interhospital transportation in Japan.

Results: The underlying cardiac diseases were dilated cardiomyopathy in 25 patients, restrictive cardiomyopathy in 12 patients, and acute myocarditis in 5 patients. Twenty-six patients were transferred by land and 16 patients by air. The continuation of intensive care was mandatory especially in 22 cases (52.3％) with ventilator and 14 (33.3％) with PCPS. More than 80％ of cases required VAD implantation after interhospital transport. In addition, 8 cases who needed treatment intensification after transportation tend to be younger. Ten patients underwent heart transplantation, whereas 11 cases were deceased. It is also important to consider appropriate blood access and to provide sufficient information to family members.

Conclusion: Early interhospital collaboration and transport planning based on a patient’s condition are essential for the treatment of severe heart failure in pediatric patients. Interhospital transportation should be supported by a medical team with special experience. To improve the prognosis of severe heart failure in children, we need to consider further improvement in the management of interhospital medical transport.

Pulmonary veno-occlusive disease (PVOD) is a rare condition that results in pulmonary hypertension caused by the occlusion of the peripheral pulmonary veins. A 1-month old infant with patent ductus arteriosus presented in critical condition with pulmonary hypertensive crisis. Cardiac catheterization revealed severe pulmonary hypertension (pulmonary to systemic arterial pressure ratio, 1.3; mean pulmonary arterial pressure, 43 mmHg; pulmonary wedge pressure, 6 mmHg; pulmonary vascular resistance, 10.3 units·m²). The patient was started on combination therapy, including continuous intravenous epoprostenol. Although drugs targeting pulmonary arterial hypertension (PAH) were initially able to improve his hemodynamic status, he gradually developed pulmonary edema. Histopathological finding of lung biopsy specimen showed PAH, so he was diagnosed with idiopathic PAH. However, he experienced recurrent pulmonary edema and progressive right heart failure. One year after admission, the patient died from severe heart failure. Histopathological autopsy findings of the lung showed pulmonary venous changes and intimal thickening of the pulmonary veins, and a diagnosis of PVOD was made. Pulmonary arterial changes included cellular and fibrous thickening of the intima, severe medial hypertrophy, and adventitial thickening with plexiform lesions (Heath–Edwards grade 4). A correct diagnosis in this case could not be made by single lung biopsy. Our experience suggests that we should suspect PVOD when patients receiving PAH therapy develop recurrent pulmonary edema, as the only available method of PVOD treatment is early lung transplantation.

We describe a male infant who was diagnosed in utero with pulmonary atresia and an intact ventricular septum (PA-IVS) and diagnosed with aortocoronary atresia (ACA) by cardiac catheterization after birth. He was delivered at full term and appeared normal for gestational age. Electrocardiography findings on day 3 of life showed ST depression while crying, and right ventricle-dependent coronary circulation (RVDCC) was suspected. Cardiac catheterization findings confirmed PA-IVS and ACA. We evaluated the blood flow of sinusoidal communication (SC) during the clinical course using pulsed-wave Doppler echocardiography. He underwent a Blalock–Taussig shunt and an ascending aorta-to-right ventricle shunt (Ao-RV shunt) on day 41 of life. At the time of delivery, SC flow was antegrade from the right ventricle (RV) to the intramyocardium at systole and retrograde from the intramyocardium to the RV at diastole. Antegrade SC flow became biphasic after the Ao-RV shunt and increased at end-diastole. Furthermore, the increased oxygenation of SC blood due to the Ao-RV shunt helped to improve the coronary circulation. This novel Ao-RV shunt approach is suitable for treating PA-IVS and ACA.

Surgical intervention after the Fontan procedure includes Fontan conversion, arrhythmia surgery, and atrioventricular valve repair/replacement. One possible complication is conduit stenosis, but few reports discuss this procedure. In this study, we discuss two patients who underwent conduit replacement after extracardiac total cavopulmonary connection to treat conduit stenosis. Patient 1 was a 20-year-old man diagnosed with tricuspid atresia who underwent the Fontan procedure at 3 years of age. As an adult, he developed complete atrioventricular block, and pacemaker implantation was planned. Further examination showed moderate neoaortic valve regurgitation and extracardiac conduit stenosis. He successfully underwent conduit replacement, neoaortic valve replacement, and pacemaker implantation. Patient 2 was a 20-year-old man with pulmonary atresia. At 5 years of age, he underwent the Fontan procedure, and at 19 years of age, he presented with malaise, melena, and hemoptysis. Cardiac catheterization demonstrated severe conduit stenosis with a 14-mm Hg pressure gradient. Conduit replacement was performed successfully. Conduit stenosis after Fontan completion is a rare but serious complication, and awareness of this complication is important during long-term follow-up, especially when cardiac imaging shows a curved conduit.