Persistent high fever for more than 10 days during acute phase is a risk factor for endothelial dysfunction in children with a history of Kawasaki disease.

BACKGROUND: Endothelial dysfunction has previously been reported in children with a history of Kawasaki disease, but the determinants of endothelial function in Kawasaki disease patients are still unknown. In this study, we investigated endothelial function in Kawasaki disease patients and attempted to identify risk factors for persistent endothelial dysfunction. METHODS: Using high-resolution ultrasound, we measured the percent flow-mediated dilatation, an arterial response to reactive hyperemia, to evaluate endothelial function in 67 patients with a history of Kawasaki disease and 28 age- and sex-matched control subjects. We divided the Kawasaki disease patients into a group with impaired endothelial function (the percent flow-mediated dilatation below -2 standard deviations of the control group) and a group with normal endothelial function (the percent flow-mediated dilatation more than -2 standard deviations of control). Logistic multiple regression analysis was performed to identify independent predictors of impaired endothelial function. RESULTS: In Kawasaki disease patients, the percent flow-mediated dilatation was significantly lower than in the control subjects (9.8±3.6%, compared with 13.1±3.4%, p<0.01). In 13 Kawasaki disease patients (3 patients with coronary artery lesions and 10 patients without coronary artery lesions), the percent flow-mediated dilatation was below -2 standard deviations of control. Logistic multiple regression analysis showed that a febrile period of longer than 10 days during the acute phase was the significant risk factor for endothelial dysfunction (odds ratio: 8.562; 95% confidence interval: 1.366-53.68). Presence of coronary artery lesions was not a determinant of endothelial dysfunction. CONCLUSIONS: Systemic endothelial dysfunction exists in children with a history of Kawasaki disease, and a febrile period of longer than 10 days during the acute phase is an independent predictor of endothelial dysfunction irrespective of coronary artery involvement.

[A case of fulminant myocarditis successfully treated by percutaneous cardiopulmonary support after 50 minuite-cardiopulmonary resuscitation].

We report a case of an 8-year-old girl with fulminant myocarditis successfully treated with percutaneous cardiopulmonary support (PCPS). She was first taken to our hospital for treatment of suspected infective enterocolitis since her main symptoms were fever, vomiting and diarrhea. On day 2 after admission, her ECG showed wide QRS and echocardiography demonstrated severe hypokinesis. She was transferred to the ICU with suspected acute myocarditis. On admission to the ICU, circulatory collapse was not detected. ECG showed severe bradycardia and ventricular fibrillation after intubation. Cardiopulmonary resuscitation was performed immediately for 50 minutes prior to initiation of PCPS. She was treated intensively with catecholamines, plasma exchange, continuous hemodiafiltration, high-dose gamma-globulin, and high dose methylprednisolone. Hypothermia therapy was also performed. She was weaned from PCPS on day 6 after initiation of PCPS. The patient was finally discharged from the hospital without any neurological complications on day 68 after weaning from PCPS. The proportion of patients in whom cardiopulmonary resuscitation was performed or having ventricular tachycardia or fibrillation were higher in non-survivors than in survivors.

Association of uric acid with obesity and endothelial dysfunction in children and early adolescents.

BACKGROUND: Hyperuricemia in adults is known to be associated with hypertension, the metabolic syndrome and cardiovascular disease. The purpose of this study was to elucidate the factors associated with hyperuricemia in obese children and early adolescents and to investigate the threshold serum level of uric acid (UA) for the metabolic syndrome in children. METHODS: We assessed anthropometric measurements, blood pressure, body composition and biochemical data in 1,559 obese children. To assess endothelial dysfunction, flow-mediated dilatation (FMD) was measured in 92 children. The correlations between serum UA levels and various parameters were examined. The threshold serum UA level for the metabolic syndrome was calculated by receiver-operating characteristic (ROC) curve analysis. RESULTS: Serum UA levels were positively correlated with lipids in both boys and girls, and they were inversely correlated with FMD in the boys but not the girls. The threshold serum UA level for the metabolic syndrome was 5.25 mg/dl in boys and 5.05 mg/dl in girls. However, the specificity and sensitivity of ROC curve analysis are not so striking. CONCLUSION: The correlation between UA and FMD showed gender differences and might be affected by the hormonal status. The cutoff level of serum UA as a marker of the metabolic syndrome in obese children was affected by both age and gender.

Molecular storage of ozone in a clathrate hydrate: an attempt at preserving ozone at high concentrations.

This paper reports an experimental study of the formation of a mixed O(3)+ O(2)+ CO(2) hydrate and its frozen storage under atmospheric pressure, which aimed to establish a hydrate-based technology for preserving ozone (O(3)), a chemically unstable substance, for various industrial, medical and consumer uses. By improving the experimental technique that we recently devised for forming an O(3)+ O(2)+ CO(2) hydrate, we succeeded in significantly increasing the fraction of ozone contained in the hydrate. For a hydrate formed at a system pressure of 3.0 MPa, the mass fraction of ozone was initially about 0.9%; and even after a 20-day storage at -25°C and atmospheric pressure, it was still about 0.6%. These results support the prospect of establishing an economical, safe, and easy-to-handle ozone-preservation technology of practical use.

[Arterial switch operation for transposition of the great arteries with situs inversus and mirror image dextrocardia].

We report a successful arterial switch operation for complete transposition of great arteries with atrial and visceral situs inversus totalis and mirror image dextrocardia in a 12-day-old infant girl. The aorta was located left side-by-side to the pulmonary trunk with a single coronary artery (mirror image of 1RLCx). After French maneuver, the posterior circumference of the neo-aorta was reconstructed. Then the coronary button was transplanted into the neo-aorta with a trap door technique carefully avoiding any twist and over-stretch. The neo-pulmonary trunk was reconstructed with an autologous pericardial patch and sutured to the longitudinal incision made into the left central pulmonary artery. The baby was discharged from hospital and has been doing well without any morbidity relating myocardial ischemia.

Repair of persistent truncus arteriosus without a conduit: sleeve resection of the pulmonary trunk from the aorta and direct right ventricle-pulmonary artery anastomosis.

OBJECTIVE: Establishing a new continuity between the right ventricle and the pulmonary artery is the mainstay of repair for persistent truncus arteriosus. We used the Tran Viet-Neveux technique without a Lecomte maneuver to construct the connection without a conduit. Here, we retrospectively review the mid-term surgical results to examine the effectiveness of this approach. METHODS: A cylindrical segment incorporating both pulmonary artery branches was sleeve-resected from the truncal artery. The cylindrical segment was cut in the middle and two truncal arterial flaps were combined to form the posterior floor of the new pulmonary arterial trunk. The edge of the floor was attached directly to the superior margin of an oblique incision made in the left-anterior wall of the right ventricle. A polytetrafluoroethylene monocusp was attached to the lower half margin of the right ventricular incision. A large glutaraldehyde-treated pericardial patch was used to form the anterior hood of the new right ventricular outflow tract. Both great arteries were located in a normal spiral configuration. RESULTS: Ten babies (range: 3 days to 9 months of age) underwent this procedure. The Collett-Edwards classification of persistent truncus arteriosus was type I in five cases and type II in five others. There was one hospital death due to severe respiratory distress. During follow-up (36-60 months, median 54 months), only one re-operation was required to enlarge a left branch pulmonary artery stenosis. Follow-up echocardiography showed pulmonary regurgitation (mild two, moderate seven, and severe one) and mild flow acceleration in the left pulmonary artery branch and right ventricle-pulmonary artery connection in one case. CONCLUSION: This simple modification for surgical correction of persistent truncus arteriosus may be an effective alternative that overcomes conduit-related problems.

Meconium aspiration delays normal decline of pulmonary vascular resistance shortly after birth through lung parenchymal injury.

BACKGROUND: Persistent pulmonary hypertension of the newborn is often associated with meconium aspiration syndrome (MAS) or perinatal asphyxia. OBJECTIVE: To determine the effect of meconium or asphyxia on pulmonary arterial pressure and circulating levels of vasoactive substances, we conducted a prospective study of 54 term infants, including infants with meconium-stained amniotic fluid with normal (MSAF) or abnormal (MAS) chest X-ray findings, infants with perinatal asphyxia, and controls. The purpose of this study was to determine the group most likely to have elevated pulmonary arterial pressure and a disturbed balance between vasoactive substances. METHODS: To estimate the pulmonary arterial pressure by echocardiography, we used the ratio of the right to left systolic ventricular pressure (RVP/LVP ratio). We measured the plasma concentrations of endothelin-1 (ET-1), cyclic guanosine monophosphate (cGMP) as an indicator of nitric oxide (NO) production, and 6-keto-prostaglandin F(1)α (6-keto-PGF(1)α) for the estimation of prostacyclin concentration. We also measured KL-6 as a marker of lung injury. RESULTS: The RVP/LVP ratio was significantly higher in the MAS group than the other groups on day 0. Although ET-1 and 6-keto-PGF(1)α levels were comparable among all groups, the cGMP level on days 3-5 and the KL-6 level throughout the first postnatal week were significantly higher in the MAS group. CONCLUSIONS: It is possible that meconium aspiration delays normal decline of pulmonary vascular resistance shortly after birth through lung parenchymal injury. The subsequent increase of cGMP in MAS may be an adaptive response to prevent further elevation of pulmonary arterial pressure by inducing NO.

Clathrate hydrates for ozone preservation.

We report the experimental evidence for the preservation of ozone (O(3)) encaged in a clathrate hydrate. Although ozone is an unstable substance and is apt to decay to oxygen (O(2)), it may be preserved for a prolonged time if it is encaged in hydrate cavities in the form of isolated molecules. This possibility was assessed using a hydrate formed from an ozone + oxygen gas mixture coexisting with carbon tetrachloride or xenon. Each hydrate sample was stored in an air-filled container at atmospheric pressure and a constant temperature in the range between -20 and 2 degrees C and was continually subjected to iodometric measurements of its fractional ozone content. Such chronological measurements and structure analysis using powder X-ray diffraction have revealed that ozone can be preserved in a hydrate-lattice structure for more than 20 days at a concentration on the order of 0.1% (hydrate-mass basis).

Oral sildenafil for persistent pulmonary hypertension early after congenital cardiac surgery in children.

OBJECTIVE: Sildenafil is a strong pulmonary vasodilator that increases the intracellular cyclic guanosine monophosphate concentration through inhibition of phosphodiesterase-5. We assessed the benefit of oral sildenafil for persistent pulmonary hypertension early after congenital cardiac surgery in paediatric patients. METHODS: Sildenafil was administered at a starting dose of 0.5 mg kg(-1) following admission to the intensive care unit. With careful monitoring of haemodynamics, the dose was increased stepwise by 0.5 mg kg(-1) every 4-6 h up to a maximum of 2 mg kg(-1). After successful weaning from a ventilator and from other vasodilators, sildenafil was gradually discontinued over the next 5-7 days. RESULTS: A retrospective review of medical records showed an age distribution of <1 month (n=26), > or = 1-<6 months (n=36), > or = 6-<12 months (n=19), 1-3 years (n=8), 4-9 years (n=9) and >10 years (n=2) at the time of surgery. The surgeries were performed for ventricular septal defect closure (n=17), arterial switch (n=30), truncus arteriosus repair (n=10), complete atrioventricular septal defect repair (n=12), total anomalous venous drainage repair (n=9), and other open-heart surgery (n=22). The aforementioned concomitant inhaled nitrous oxide treatment was performed in 66 patients. Pulmonary arterial pressure decreased in 28, was unchanged in five and elevated in one patient out of the total of 34 cases for which data from continuous pressure monitoring were available. Bosentan was added in three cases with persistent symptoms due to pulmonary hypertension despite sildenafil treatment. After sildenafil administration, modest oxygen desaturation occurred in seven cases, but no 'rebound' pulmonary hypertension occurred. There were no significant adverse events during sildenafil treatment. CONCLUSIONS: Our results suggest that oral sildenafil is a safe and effective alternate for persistent pulmonary hypertension following congenital heart surgery in children.