Tissue Doppler imaging (TDI) is an echocardiographic technique that uses Doppler principles to measure the velocity of myocardial motion. In adults, TDI is recommended to assess systolic and diastolic longitudinal ventricular function by obtaining spectral traces from the mitral and tricuspid ring in the 4-chamber view. There are many studies of left or right ventricular function assessed by TDI in various heart diseases during the pediatric period. However, age-related changes of normal values of TDI parameters make it difficult to interpret data in an individual child in actual clinical practice. This review provides normal values for various TDI parameters and discusses the clinical usefulness and limitations of TDI in the pediatric age group. Mitral or tricuspid annular plane systolic excursion is another method to assess longitudinal function of both ventricles by M-mode. This review also shows normal values and clinical implications of this simple method. Because of their ready availability using conventional echocardiographic equipment, these methods should become a part of the routine assessment of cardiac function in children.

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Speckle tracking echocardiography tracks the motion of a small area within the cardiac muscle. It is a useful clinical tool to simultaneously assess the local and global functions, as well as the cardiac synchrony or dyssynchrony. It has overcome the issue of angle dependency, a limitation of tissue Doppler imaging. When using a modern echo machine with this function, echocardiographers capable of acquiring clear images of the apical 4-chamber and short axis views can easily begin using speckle tracking echocardiography. The following three steps are required to obtain analysis results : 1) clear recordings of a B-mode motion video with electrocardiography; 2) selection of the type of analysis; and 3) specifying the region of the interest. However, not many pediatric cardiologists perform speckle tracking echocardiography, partly because it is percieved as complicated. This review will summarize the important basic knowledge and limitations needed to start using Speckle tracking echocardiography.

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Recently, revolutionary advancements regarding the ultrasonic apparatus, three-dimensional (3D) echo probe, and PC analysis workstations have been achieved, and these have drastically improved the quality of 3D imaging. Additionally, 3D echocardiography has become one of the most useful diagnostic and therapeutic tools for congenital heart disease. One of the most effective applications is to provide critical information of complicated intracardiac 3D structures of the heart for planning cardiac surgery. This includes the creation of an intracardiac route via the ventricular septal defect in patients with a double outlet right ventricle, valvuloplasty for complicated atrioventricular valve regurgitation, or the repair of intracardiac stenotic lesions (e.g., pulmonary venous obstruction). The digitally acquired 3D volume data is reconstructed by “cropping” and then complex intracardiac structures can be observed from the surgeon’s standing point (i.e., surgeon’s viewpoint). Therefore, this technology can serve as the basis of profound communication between cardiologists and cardiac surgeons. In this chapter, I would like to address how to use 3D echocardiography as a guide for surgical repair in actual clinical practice and explain the process in detail for the pediatric cardiology trainees to understand with ease.

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Congenital coronary anomalies are classified into four categories: ① anomalies of the location of the orifice or abnormal course of the coronary artery; ② coronary ostial stenosis or atresia; ③ anomalies of the coronary vessels; and ④ anomalous termination of the coronary artery. The anomalous location of the orifice includes ectopic ostium within the aortic root and ectopic origin from other vessels, such as a pulmonary artery or brachiocephalic artery. These coronary anomalies present either as an isolated anomaly or in combination with other anomalies. Although congenital coronary anomalies are rare, we should be aware of them as the first 2 types of anomalies have a potential for life-threatening presentations, including myocardial infarction, arrhythmia, or sudden death. However, early detection by mass electrocardiographic screening of school-aged children in Japan is arduous. Congenital coronary anomalies are now recognized as one of the leading causes of sudden death in young athletes second only to cardiomyopathies, making early detection critical. Congenital coronary anomalies often occur alone, however, they may also be accompanied by congenital heart diseases, and some of the coronary anomalies may have a significant impact on the postoperative outcome. Increasing awareness of these pathologies may help earlier diagnosis and treatment of this potentially life-threatening disease.

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The cause of perioperative coronary-related complications in congenital heart surgery is either procedure-related or an attribute of the disease itself. The representative example of the former is an arterial switch operation for the transposition of the great arteries or double outlet right ventricle. In performing safe and adequate coronary transplantation, careful observation of not only the coronary patterns but also coronary transplantation method, spatial relationship of the great arteries, and the method of pulmonary artery reconstruction are comprehensively considered. In contrast, an example of the latter is pulmonary atresia with an intact ventricular septum associated with the right ventricle-coronary sinusoidal communication. To avoid perioperative coronary ischemia, special attention must be paid to intraoperative management, including the perfusion and operative methods. In addition to obtain a precise preoperative diagnosis and careful intraoperative observation, the awareness about the fact that many congenital heart diseases could have a coronary anomaly may help to avoid coronary-related complications in congenital heart surgery.

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Coronary artery anomalies are not uncommon, occurring in 1.3％ of the overall population. Most patients are asymptomatic, and the condition is found incidentally. However, these patients are potentially at a high risk for life-threatening complications. The left coronary artery originating from the right Valsalva sinus with an interarterial course is known to be a cause of sudden death in young athletes and should be surgically repaired even if the patient is asymptomatic. Exercise electrocardiography in this anomaly is not reliable, and a coronary imaging test, such as echocardiography, computed tomography angiography, or coronary arteriography, is needed when this anomaly is suspected. The anomalous origin of the left coronary artery may cause severe myocardial ischemia, left ventricular dysfunction, and mitral regurgitation in early infancy. Early surgery is indicated to establish a two-artery coronary system. Coronary arteriovenous fistula may cause myocardial ischemia and heart failure, and the indication for surgery is based on clinical symptoms. Preoperative coronary imaging is important in both catheter occlusion and surgical occlusion. Coronary artery anomalies should be included in the differential diagnosis of cardiac symptoms, such as angina, myocardial ischemia, arrhythmia, and heart failure.

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The aim of this article is to describe the physical examination and physical findings for pediatric cardiologists. The most important point is to build a diagnostic hypothesis from four diagnostic methods (medical examination by interview, physical examination, laboratory examination, and diagnostic imaging). Subsequently, the findings should be explained by the diagnostic hypothesis. We can more easily conduct a physical examination when we understand the basic concepts, i.e., the cardiac cycle, the three major mechanisms of cardiomegaly (shunt lesions, valvular regurgitation, and myocardial damage), and the anatomical position of the great vessels and cardiac chambers. We estimate the size and pressure of vessels and cardiac chambers while conducting a physical examination. The physical findings should also be explained by the diagnostic hypothesis that is built each time. If the findings cannot be explained by the hypothesis, we should build the hypothesis again.

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The Fontan operation has certainly changed the quality of life in patients with congenital heart disease with functionally single ventricle, and the perioperative survival has dramatically improved owing to recent medical advances and modifications of the surgical technique. The postoperative course of these patients varies widely with relatively high morbidity and mortality compared with the course of patients in whom congenital heart disease has been treated with other types of definitive repairs. However, long-term management strategies of these patients have not yet been established because of a lack of information on the entire postoperative course of the unique hemodynamics and insufficient understanding of the pathophysiology of this type of heart failure. Our institute has developed a unique approach to overcome these clinical problems and has tried to provide these patients with better medical care using precise serial comprehensive assessments of the pathophysiology, including hemodynamics, cardiopulmonary exercise testing, hepatorenal conditions, and even metabolic abnormalities. Thanks to these daily practices, we have clarified some of the complicated heart failure pathophysiology to some extent, and some patients have benefited from these results. However, additional complications have emerged as these patients aged and raise many questions.

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The Blalock–Taussig shunt (BTS) operation has been a cornerstone procedure as the first palliative operation for congenital heart disease with severely reduced pulmonary blood flow (PBF). Although the ideal PBF provided by BTS is crucial for an uneventful postoperative course, particularly in neonates and infants with single ventricular physiology, there are no standardized criteria for selection of the shunt graft size and anastomosis site. Excess PBF results in acute distress of the systemic circulation, and insufficient PBF requires another BTS surgery. Adjustment of PBF is a definitive solution for these problems that occur with BTS use. Therefore, we developed a simple device to percutaneously control the shunt graft flow with a constrictor balloon connected to a subcutaneous port. The device provided good flow control by inflating and deflating the balloon ex vivo and in vivo for up to 3 months (in a canine model of replacement of the right carotid artery with a small graft wrapped with the device). This simple device could enable the regulation of the PBF through a small vascular graft and help prevent severe morbidity and mortality even in the clinical setting of BTS.

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Objectives: Few studies have examined congenital heart disease (CHD) in very low-birth-weight (VLBW) infants. This study was conducted to characterize the incidence, distribution, and midterm outcomes of CHD in VLBW infants at our hospital.
Methods: We reviewed case data obtained from 456 VLBW infants at our neonatal intensive care unit (NICU) between January 2000 and December 2006. Cardiac diagnoses were confirmed using echocardiography, surgery, and autopsy. Cases of arrhythmia with a normally structured heart, isolated patent duct arteriosus, and interatrial defect ＜5.5 mm were excluded.
Results: CHD was detected In 26 infants (5.7％). The VLBW infants with CHD showed a significantly higher rate of genetic syndromes and extracardiac malformations compared with non-CHD infants (CHD group, 38.5％ and 34.6％; non-CHD group, 1.9％ and 7.2％, respectively). The most common lesions were ventricular septal defect [n＝10, (38.5％)], coarctation of the aorta [n＝3, (11.5％)], atrioventricular septal defect [n＝2, (7.7％)], pulmonary stenosis [n＝2, (7.7％)], and aortic valve stenosis [n＝2, (7.7％)]. Ten infants with CHD required surgical treatment, and 15 infants (57.7％) needed medical treatment, including inotropic agents. The relative incidence of necrotizing enterocolitis, chronic lung disease, and intracranial hemorrhage was similar in CHD and non-CHD infants. The mortality rate of CHD infants in our NICU was significantly higher than that of non-CHD infants (26.9％ vs. 11.9％). Moreover, 5-year survival was significantly lower for CHD infants (65.4％) than for non-CHD infants (86.2％).
Conclusions: CHD occurs more frequently in VLBW infants than in the general Japanese live-born population. VLBW infants with CHD have a higher incidence of severe CHD and genetic and extracardiac malformations and higher mortality than non-CHD infants.

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Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a rare cause of heart failure in the young. We report a pediatric case of ARVC with severe heart failure. The patient was a 9-year-old boy who was noted to have paroxysmal ventricular contractions at his regular school electrocardiogram check-up. Cardiac magnetic resonance imaging showed severe biventricular enlargement and dysfunction. He underwent orthotopic heart transplantation at 10 years of age. Genetic testing revealed two mutations related to ARVC. He had a nonsynonymous single-nucleotide polymorphism in desmoglein 2 (DSG2; c.1481 A＞C: p.Asp494Ala) and transmembrane 43 (TMEM43; c.601G＞A: p.Asp201Asn). Coexistence of these mutations may lead to severe ARVC in the young patient.

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Nemaline myopathy, a common type of congenital myopathy, rarely presents with cardiac involvement. We report a female patient with atypical hypertrophic cardiomyopathy and nemaline myopathy associated with ACTA1 mutation. She presented with an abnormal gait at the age of 18 months. Slowly progressive muscle hypotonia and weakness were recognized at the age of 2 years. A cardiovascular assessment performed at the age of 7 years showed atypical hypertrophic cardiomyopathy. The diagnosis of nemaline myopathy was confirmed by a skeletal muscle biopsy, and an ACTA1 mutation was identified at the age of 8 years. Echocardiography and cardiac catheterization revealed severe diastolic dysfunction and atypical concentric left ventricular hypertrophy between the base and the apex of the heart. A β-blocker was administered without effect, and the patient died of ventricular fibrillation accompanied by heart failure at the age of 9 years. Some of the clinical features of this case resembled the recently reported hypertrophic cardiomyopathy associated with thin-filament gene mutations. Nemaline myopathy may result in fatal cardiomyopathy; therefore, careful assessment and appropriate management for cardiovascular involvement are essential.

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