A characteristic of fetal circulation is that the relationship between the right and left ventricles is parallel, with one intracardiac shunt (foramen ovale) and two unexpected shunts (ductus venosus and ductus arteriosus) in which lung circulation is not established and fetal oxygen is supplied from the placenta. The main blood flow streams from the right ventricle toward the descending aorta through the main pulmonary artery and ductus arteriosus, with little blood circulating in the lungs. Therefore, an evaluation of the right heart system, including the placenta and three shunts, is important for determining the cardiac function of the fetus. Until the third trimester of pregnancy, the pulmonary blood flow increases to four times that in the first trimester, and left ventricle blood flow that normally bears 45% of the total cardiac output in fetal circulation increases 2–3 times after birth. It is important to understand the characteristics of fetal circulation and its dramatic transition to the postnatal circulation to delineate the pathophysiology of congenital heart diseases.

With the advent of three-dimensional (3D) echocardiography, we are now able to assess the 3D geometry and coordinated function of a complex structure, the atrioventricular valve (AV). Many studies have analyzed the effects of annulus or leaflet morphology or the position of the papillary muscles on AV function. As early as the 1980s, published papers have analyzed AV valve annulus motion using 3D information acquired by rotating an echo-probe around the axis of the heart and saving the two-dimensional echocardiographic images of each cardiac cycle. In the 2000s, real-time 3D transthoracic and transesophageal echocardiography subsequently became commercially available and proved their usefulness in actual clinical practice. The two methods for visualizing 3D echocardiographic data are volume rendering and multiplanar reconstruction. Volume rendering enables understanding of the entire AV valve, whereas multiplanar reconstruction contributes to a more precise analysis or quantitative evaluation. Here studies related to AV valve function mainly analyzed using 3D echocardiography are discussed and future directions are described.

Two-dimensional (2D) speckle tracking imaging is a relatively new method to evaluate cardiac function by echocardiography. Myocardial deformation was calculated by frame-by-frame tracking of the change in the location of the speckle in the region of interest on the ultrasound image. A quantitative assessment for wall motion abnormalities was made possible by strain value measurements. In recent years, the impact of left ventricular strain assessments, particularly “global longitudinal strains,” using speckle tracking echocardiography has been demonstrated, particularly in the prediction of prognosis and cardiac events in heart failure and early detection of subclinical myocardial damage in several myocardial diseases. Moreover, few investigations have analyzed ventricular strain in pediatric patients with congenital heart disease. The latest ultrasonic diagnostic apparatus allows more easy and accurate strain measurement using the speckle tracking method. Future clinical application is expected in the field of pediatric cardiology. This study reports the basic concepts, methodology, and latest investigations, including pediatric cardiovascular issues, related to speckle tracking echocardiography.

The number of sudden deaths of school students has been decreasing year by year in Japan. The incidence of sudden death in Japanese schools after 2010 decreased to lower than 0.1 per 100,000 students per year from 0.5 in the 1980’s. The use of an automated external defibrillator (AED) by caregivers in schools may have contributed to this result. Some cases of sudden death occur because of previously diagnosed cardiovascular disease identified by the screening system for students in Japanese schools. However, more than half of cases of sudden cardiac arrest in schools are not previously diagnosed with cardiac disease and are partly identified on autopsy. A large part of these are probably caused by genetic life-threatening arrhythmias; therefore, it is necessary to perform as many genetic examinations as possible. Autopsies occasionally reveal structural heart disease as the cause of sudden unexpected cardiac arrest. However, the Japanese forensic system is limited to several big cities. It may be necessary to reconsider the screening system for discovering causative cardiac disease that is often discovered on autopsy. Besides sudden death due to cardiovascular disease, some cases are secondary to central nervous system issues. Sudden unexpected deaths in preschool children, including sudden infant death syndrome, are also reported every year. These also need to be analyzed and discussed for prevention. Cooperation of the screening system and the chain of survival will be expected to contribute to a more marked advance for preventing sudden death.

Background: Lesions of congenital heart disease require stereoscopic understanding, which can be enhanced by three dimensional imaging. In Shizuoka Children’s Hospital, three-dimensional rotational angiography (3DRA) is in use since 2013.

Purpose: To report the efficacy of 3DRA in congenital heart disease.

Objective and Methods: We evaluated the advantage of 3DRA in 24 patients. Secondly, we reviewed 15 patients who had a single target lesion in the pulmonary artery after Rastelli procedure, visualized on 3DRA (n=5) or CT (n=10) at the time of intervention, between 2010 and 2016. Procedural parameters were compared between the two groups.

Results: All reconstructed 3DRA images provided adequate diagnostic quality and by Likert scale, classified as either “essential” or “very useful” for pre-operative or interventional planning in 75% of patients, especially in complex vascular lesions. No complications occurred. There was no significant difference with respect to procedure time, fluoroscopy time, radiation dose of angiography between 3DRA and CT. Total contrast media used in 3DRA group (3.9mL/kg) was significantly lower than that in the CT group (5.9mL/kg; p=0.003).

Conclusions: 3DRA is a safe and effective modality in pediatric cardiovascular area. Wide-angled, stereoscopic image reconstruction allows for a more objective evaluation. Use of 3DRA was comparable to that of CT with respect to procedure time, fluoroscopy time, and radiation dose. Total contrast media used was significantly less in the former.

Persistent fifth aortic arch (PFAA) is a rare congenital anomaly and may cause the same clinical symptom as coarctation of the aorta. We experienced two neonatal cases with PFAA and interrupted fourth aortic arch. A 15-day-old boy was referred to our hospital because of ductal shock. He underwent the emergent aortic arch repair. A 7-day-old boy was admitted to our institute for suspected coarctation of the aorta. There was reverse blood flow from the left subclavian artery to the descending aorta. He underwent the elective aortic arch repair at 14 days of age. The ductal tissue was resected, and a proximal part of PFAA was used for aortic arch reconstruction in both patients. Although one patient required balloon dilatation 2 months after the surgery, neither patient had a pressure gradient between the upper and lower extremities 11 and 10 months after surgery, respectively. Histological findings of PFAA wall showed three normal layers as observed in a normal aortic wall. This suggested that PFAA wall could be used for aortic auch reconstruction.

A 12-month-old boy who was diagnosed with a large patent ductus arteriosus (PDA) and pulmonary hypertension (PH) in another hospital was admitted to Chukyo Children Heart Center for catheter intervention. After transcatheter PDA closure, he developed myocardial dysfunction accompanied by elevated cardiac enzyme levels and an abnormal Q-wave on electrocardiography. Anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA) was detected on follow-up transthoracic echocardiography, and open chest surgery was performed. ALCAPA typically manifests in infancy with signs and symptoms of heart failure that are secondary to ischemic cardiomyopathy. However, it is very difficult to diagnose when additional congenital heart disease, for example, PDA, is present, because left coronary perfusion is maintained by PH. If PDA is treated without the diagnosis of ALCAPA, sudden deterioration may occur. We concluded that we should confirm the origin of the coronary artery using left ventriculography or aortography before transcatheter PDA closure if we cannot rule out the possibility of coronary artery anomalies by careful transthoracic echocardiography.

A 32-year-old American man visited our outpatient clinic for a chief complaint of exertional dyspnea. His medical history was remarkable for the diagnosis of d-TGA, Rastelli operation, right ventricular outflow tract (RVOT) reimplantation of the conduit twice, and plastic surgery for a thoracic deformity. Because of the progression of RVOT stenosis, a Melody valve was implanted when he was 24 years old and living in New York. On physical examination, harsh systolic ejection murmur of Levine 3/VI at his third left sternal border was audible. Chest X-ray demonstrated three metal plates bridging his bilateral thorax. Echocardiography revealed paradoxical movement of the interventricular septum, flattened left ventricular cavity, and 55–60 mmHg pressure gradient due by tricuspid regurgitation. The stenotic site of his RVOT was not apparent because of the artifact. The plasma hANP and BNP levels were 54.1 and 54.7 pg/ml, respectively. Because of his past medical history of multiple cardiovascular and thoracic surgeries, surgical reconstruction of his stenotic RVOT was assessed to be too risky. A Melody valve-in-valve implantation was performed in Los Angeles, California, and he returned to our hospital 1 month later. His quality of life has significantly improved, and his heart murmur changed to a soft murmur. During the procedure, the stent fracture was confirmed to be responsible for RVOT restenosis, although the frontal view chest X-ray failed to reveal it. Approval is awaited for clinical use of the Melody valve in Japan.

Some patients with single ventricular physiology reach adulthood without Fontan completion because of risk factors for the procedure. A 40-year-old woman diagnosed with mitral atresia, transposition of the great arteries, ventricular septal defect, and subvalvular pulmonary stenosis had not been considered as a candidate for the Fontan procedure because of pulmonary hypertension. Lung biopsy revealed only mild medial wall thickness in the preacinar small pulmonary artery. Fontan completion following bidirectional Glenn (cavopulmonary anastomosis) procedure, atrioventricular (AV) valve repair, and pulmonary artery banding was successfully performed. Postoperatively, cardiac dysfunction with AV valve regurgitation and cardiac dyssynchrony developed. AV valve replacement and cardiac resynchronization therapy improved her ventricular function. She is doing well 5 years and 3 months postoperatively.