Introduction: In Okayama and Hyogo, Yersinia pseudotuberculosis (YPT) infection is present in about 10% of patients with Kawasaki disease (KD). These patients are older and have a higher incidence of re-administration of immunoglobulin (re-IVIG) and higher prevalence of coronary artery aneurysm (CAA) compared to KD patients without YPT infection.

Materials and Methods: The subjects, 208,757 cases reported in the Japanese KD National Survey (1999–2016), were divided into 8 regional groups: region-1; Hokkaido/Tohoku, region-2; Kanto, region-3; Tokyo/Kanagawa, region-4; Chubu, region-5; Kansai, region-6; Hyogo/Okayama, region-7; Chugoku/Shikoku, and region-8; Kyushu/Okinawa. These groups were compared for the age of onset of KD, rate of re-IVIG, and prevalence of CAA with the Kruskal–Wallis and chi-square tests. In addition, the onset age was categorized into 19 groups, and the proportions of patients in each age group were compared among the 8 regions.

Results: In pairwise comparisons with region-6, the age of onset was higher in region-2 (p<0.05) and lower in region-8 (p<0.001), the re-IVIG rate was lower in region-1, 2, and 3 (each p<0.001), and the prevalence of CAA was higher in region-1 (p<0.01). The proportions of patients in each age group differed among regions.

Discussion: There were regional variations in onset age of KD, re-IVIG rate, and CAA prevalence, although they were all averages in region-6. The nationwide incidence of KD associated with YPT infection is desirable to be investigated.

The coronary blood flow in cases of atresia of the left coronary artery ostium is supplied through collateral vessels from the right coronary artery. Therefore, the severity of symptoms depends on the condition of this vessel. We experienced a seven-year-old girl who complained of chest pain during exercise. We performed myocardial scintigraphy using techenetium-99m-tetrofosmin and observed the rare reverse redistribution phenomenon. We suspected myocardial ischemia. We performed coronary angiography and diagnosed her with atresia of the left coronary artery ostium. As there was no stenosis in the coronary artery in this case, the coronary artery was successfully dilated by adenosine loading, thereby increasing the coronary blood flow and thus the blood flow in the myocardium. Our findings may help prevent cardiac accident.

A 1-year-old Japanese girl with an eight-hour history of diaphoresis and emesis, died on arrival at our hospital. Investigations could not determine the cause of death. Imaging findings were consistent with postmortem changes. There were no pathological findings of virus-induced changes, fulminant myocarditis, myocyte disarray, or myocardial hypertrophy. The activity of the cardiac mitochondrial respiratory transport chain complex (MRTCC) I was reduced. Analysis of target resequencing by use of a genetic testing panel for mitochondrial diseases showed the patient had a Phe110Ile missense mutation (c.358T>A; p.F110I) in the cardiac Troponin T2 gene (TNNT2 mutation). TNNT2 mutation is one of the causes of familial hypertrophic cardiomyopathy. Our case is the first report of a patient with the TNNT2 mutation and low activity of cardiac MRTCC I.

Patients with atrial septal defects may have to undergo surgery if catheter device closure is deemed impossible. This crossover is a decisive moment as the sternotomy skin incision scar could be a significant psychological burden for patients. Herein, we present the case of a seven-year-old female patient who was diagnosed with an atrial septal defect with a deficient inferior rim. The repair was performed through a vertical sub-axillary mini-skin incision, with the aid of an endoscope, without making an extra skin incision apart from that for femoral cannulation. The length of the main skin incision was 1.5 cm. The present case proved that an excellent cosmetic result is achievable for patients undergoing surgery for atrial septal defects.

It remains unclear how to treat patients with Kawasaki disease (KD) refractory to conventional intravenous gammaglobulin (IVIg) therapy. We report successful early aggressive combination treatment with ciclosporin and infliximab in an IVIg-resistant case. A 2-year 6-month-old boy with 5 principle symptoms was transferred to our hospital on day 3 of illness. Body temperature was 40.8°C, and appeared ill. Laboratory testing on admission showed: aspartate aminotransferase (AST), 2,439 IU/L; alanine aminotransferase (ALT), 1,142 IU/L; total bilirubin, 2.1 mg/dL; and C-reactive protein, 11.8 mg/dL. White blood cell count was 8.8×10⁹/L (85% neutrophils). Kobayashi, Egami, and Sano scores, each of which predict resistance to IVIg therapy, were 8, 5, and 3, respectively. Aspirin was not used as an anti-inflammatory agent, because of the elevated AST and ALT levels. IVIg and oral ciclosporin were administered on days 3 and 6, respectively, but fever persisted. After infliximab was administered on day 9, fever was immediately alleviated. He had no coronary aneurysms. This case suggested that third-line therapy should be performed by day 10 of illness to prevent coronary aneurysms. As additional treatment for IVIg-resistant KD, ciclosporin, infliximab and plasmapheresis should be considered, in that order. Further, aspirin may not be needed with aggressive therapies such as ciclosporin.

Double outlet left ventricle is defined as a conotruncal anomaly, where the great arteries arise entirely or predominantly from the left ventricle. Diagnosis was based on commitment of more than 50% of aortic and pulmonary annulus to the left ventricle. Absence of bilateral coni, though common, is not mandatory for diagnosis. Two young infants presented with severe cyanosis due to streaming of deoxygenated blood leading to a transposition physiology. Associated pulmonary stenosis in one worsened the hypoxia. A proposed management algorithm was based on multiple anatomical and physiological features of the disease as well as the patient size. Surgical treatment plan in these patients depend on adequacy of both ventricles, routability of the ventricular septal defect, association with pulmonary stenosis and relationship of the great arteries.

Noonan syndrome with multiple lentigines (NSML) is frequently associated with hypertrophic cardiomyopathy (HCM) with severe left ventricular tract outflow obstruction (LVOTO); however, standard HCM treatments are often ineffective. Recently, HCM attenuation was observed in the NSML mouse model treated with a mammalian target of rapamycin (mTOR) inhibitor, rapamycin; however, there have been few reports on its clinical experience. Herein, we describe our experience with the treatment using a rapamycin analog, sirolimus, in a 19-year-old adolescent boy with NSML and HCM accompanied by severe LVOTO. The patient was already diagnosed with NSML by genetic examination (heterozygous Q510E mutation in PTPN11). HCM was complicated by severe LVOTO and was refractory to conventional treatment. We initiated sirolimus treatment (1 mg/day) for 16 weeks. Echocardiographic measurement and tissue Doppler evaluation of the left ventricular diastolic function did not significantly change before and after the treatment. Although the brain natriuretic peptide levels temporarily decreased, the values at 16 weeks after sirolimus administration were almost equal to levels before administration. Cardiac magnetic resonance imaging (cMRI) at 8 weeks after sirolimus treatment revealed elevation of native T1 value in the entire left ventricular wall, suggesting fibrosis of the entire left ventricle, which seemed to be irreversible. In our case, the effect of the rapamycin analog sirolimus could not be confirmed. Given the results of cMRI, treatment may have been started too late. It remains possible that the results would have been different if treatment had been started before extensive fibrosis occurred in the myocardium.