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Biomedical subjects

Betau Hwang

Publications and source records attributed to Betau Hwang.

At least 37 records · Page 2Linked to original sources

Initial clinical experience of real-time three-dimensional echocardiography in neonates with isolated congenital ductus arteriosus aneurysm.

BACKGROUND: Congenital ductus arteriosus aneurysm (DAA) was considered rare but potentially fatal abnormality, often followed by surgical intervention after careful evaluation. This prospective study used real-time three-dimensional echocardiography (RT3DE) to assist in evaluation of neonatal DAA. METHODS: A total of 1390 full-term neonates were enrolled in this study between 2002 and 2003. They received two-dimensional echocardiographic (2DE) screening and periodic follow-up. RT3DE was performed selectively for newborns with DAA. RESULTS: DAA were detected in 116 (8.34%) newborns using 2DE. Maximum diameter of the DAAs ranged from 6.8 to 14.0 mm (8.2+/-1.1 mm). None of the cases were symptomatic or had complications related to DAA. There were no significant differences in sex and gestational age between the newborns with and without DAA. Neonates with DAA had a higher birth body weight and a higher incidence of large-for-gestational-age (P<0.05). RT3DE provided instant, consistent and reliable 3D images of DAA and its related structures and allowed for more rapid examination times and reduction of baby wait times. CONCLUSIONS: Congenital DAA is as common as has been previously reported. RT3DE is useful in assisting evaluation of DAA. Preferred images of DAA were typically visualized in the high parasternal short-axis view before the third day of life. Routine use of RT3DE is suggested to enhance assessment of neonates with DAA detected by 2DE.

Ductus Arteriosus↗

A rare vascular ring caused by an aberrant right subclavian artery concomitant with the common carotid trunk: a report of two cases.

In this report, we describe two rare cases with aortic branching anomalies. One was a 7-year-old girl who had an incomplete vascular ring caused by the presence of left aortic arch and aberrant, retroesophageal right subclavian artery associated with the common carotid trunk. The other was a 6-year-old boy who had a right aortic arch and mirror image branches of the former case. Both were asymptomatic and discovered incidentally. Three-dimensional surface rendering magnetic resonance angiography was used to confirm the diagnosis. Surgical intervention was not performed in either case because of lack of vascular ring-related symptoms. The incidence, clinical symptoms, pathogenesis and management of this rare vascular ring are discussed below.

Aortic Arch Syndromes↗

Is urorectal septum malformation sequence a variant of the vertebral defects, anal atresia, tracheo-oesophageal fistula, renal defects and radial dysplasia association? Report of a case and a review of the literature.

UNLABELLED: The urorectal septum malformation sequence (URSMS) consists of multiple systems anomalies including ambiguous genitalia, the absence of a perineal opening, an imperforate anus, and urogenital, colonic and lumbosacral anomalies. We describe a 3-day-old female infant with characteristic URSMS and review its clinical manifestations, outcomes and putative pathogenesis. We also compare its characteristics with those of the vertebral defects, anal atresia, tracheo-oesophageal fistula, renal defects and radial dysplasia (VATER) association. CONCLUSION: Although defects of the urorectal septum malformation sequence and the vertebral defects, anal atresia, tracheo-oesophageal fistula, renal defects and radial dysplasia association overlap, we believe that they are separate entities. Differentiating the urorectal septum malformation sequence from vertebral defects, anal atresia, tracheo-oesophageal fistula, renal defects and radial dysplasia association is helpful to develop appropriate clinical investigations and search for the aetiology and pathogenesis of these diseases.

Abnormalities, Multiple↗

Risk factors of prolonged postoperative pleural effusion after repair of tetralogy of Fallot.

BACKGROUND: Tetralogy of Fallot (TOF) is the most common cyanotic congenital heart disease, and total correction is the definitive treatment. Chest tube drainage of pleural effusion (PE) is essential after surgery. Prolonged PE (> 7 days) is one of the complications; it may increase hospital stay and the risks of morbidity and mortality. The aim of this study was to investigate and analyze the possible risk factors for prolonged PE after total correction of TOF. METHODS: Thirty-seven patients who received total correction of TOF between July 1999 and April 2001 were included in this study. They were divided into 2 groups according to the duration of chest tube drainage for postoperative PE: Group I had postoperative PE < or = 7 days; Group II had postoperative PE > 7 days. Detailed records were taken on patients' demographic characteristics, blood parameters, surgery, electrocardiographic and radiologic data, and angiographic and echocardiographic findings. The data of the 2 groups were compared using the Wilcoxon rank-sum test and Fisher's exact test. Risk factors were analyzed by logistic regression and model selection. RESULTS: Of the 37 patients, 16 were male and 21 were female. There were 32 patients (86.5%) in Group I and 5 (13.5%) in Group II. Mean patient age at repair was 1.82 +/- 1.29 years (range, 0.53-3.11 years). Significant differences (p < 0.05) between the 2 groups were noted for gender, age at repair, body weight, presence of wound infection, duration on heart-lung machine (bypass time), oxygen saturation before surgery, duration of endotracheal intubation, length of hospital stay, and Nakata index. These risk factors were analyzed by logistic regression and model selection. Two models were set up: Model 1--oxygen saturation before surgery, presence of wound infection, age at repair; Model 2--oxygen saturation before surgery, presence of wound infection. CONCLUSION: Prolonged PE is a significant morbidity after TOF repair. The risk factors for prolonged PE are gender, age at repair, body weight, bypass time, low oxygen saturation before surgery, wound infection after surgery, duration of endotracheal intubation, length of hospital stay, and Nakata index. Oxygen saturation before surgery and wound infection were major risk factors while age at repair was a confounder.

Age Factors↗

Cor triatriatum with repeated episodes of syncope in an eighteen month-old girl: a rare cause of cardiogenic syncope.

Syncope can be caused by either cardiogenic or noncardiogenic causes. Structural heart diseases should be considered as a possible cause of recurrent episodes of syncope if no other causes are found. We report an 18 month-old girl who presented with recurrent syncope as well as dyspnea, failure to thrive, and frequent episodes of pulmonary infections, suggesting congestive heart failure. A prominent pulmonic component of the second heart sound and congested lungs noted from chest X-rays indicated pulmonary hypertension. An echocardiogram revealed an abnormal membrane with a small orifice in the left atrium (LA). An intact atrial septum and no evidence of other congenital heart diseases were observed. The result after surgical resection of the membrane was good during follow-up. Cor triatriatum may be one of the structural heart diseases responsible for repeated unexplained syncope. An echocardiogram performed by an experienced cardiologist would facilitate the diagnosis considerably and an excellent prognosis can be achieved via surgical resection of the obstructing membrane.

Cor Triatriatum↗

Intrafamilial phenotype variation in Marfan syndrome ascertained by intragenic linkage analysis.

Marfan syndrome is an autosomal dominant fibrillinopathy caused by mutations of the fibrillin-1 (FBN1) gene. Although linkage analysis is often required to ascertain the disease status in family members, recombination is a problem. We analyzed 6 families including 18 patients using 4 intragenic microsatellite markers, located in intron 1, 5, 28, and 43, respectively, of the FBN1 gene. Haplotypes in all family members could be established, and segregation analysis showed no recombination between the markers and the disease. After confirming the diagnosis, intrafamilial analysis revealed clinical manifestations involving the ocular, cardiac, and skeletal systems. Intragenic linkage analysis in Marfan syndrome is very helpful in its diagnosis and management within affected families.

Adolescent↗

Norepinephrine induces apoptosis in neonatal rat cardiomyocytes through a reactive oxygen species-TNF alpha-caspase signaling pathway.

OBJECTIVE: Norepinephrine (NE)-induced apoptosis in cardiomyocytes is an important cause of heart failure. Previous studies revealed that reactive oxygen species (ROS) are involved in apoptosis. Tumor necrosis factor-alpha (TNF), a well-known mediator that stimulates apoptosis, is not only produced by macrophages but also by cardiomyocytes. Until now, the role of TNF and its relationship to ROS in NE-induced apoptosis of cardiomyocytes have never been investigated. METHODS: Neonatal rat cardiomyocytes were treated with various concentrations of NE. Apoptosis of cardiomyocytes was determined using the TUNEL assay. The level of secreted TNF was measured by ELISA and TNF mRNA expression was determined by semiquantitative reverse transcriptional polymerase chain reaction. Caspase activity was measured by a fluorogenic protease assay kit. Anti-TNF antibodies, caspase inhibitors and antioxidants (N-acetyl-L-cysteine or vitamin C) were added to determine if they could inhibit the apoptotic effect of NE. RESULTS: NE induced apoptosis of cardiomyocytes in a dose- and time-dependent manner. NE up-regulated TNF mRNA expression and increased TNF secretion and caspase-2,-3,-6, and -9 activities. A neutralizing anti-TNF antibody and caspase-2 and -3 inhibitors significantly attenuated NE-induced apoptosis. Antioxidants completely abrogated NE-induced TNF secretion, caspase activation, and apoptotic death. CONCLUSION: NE induced apoptosis in neonatal rat cardiomyocytes through a ROS-TNF-caspase signaling pathway.

Animals↗

Norepinephrine induces apoptosis in neonatal rat endothelial cells via down-regulation of Bcl-2 and activation of beta-adrenergic and caspase-2 pathways.

OBJECTIVES: Heart failure is associated with increased plasma norepinephrine (NE) and endothelial apoptosis. Recent reports have suggested that endothelial dysfunction is an important target for future therapies of heart failure. However, whether NE can induce endothelial apoptosis and its mechanism remains unknown. METHODS: Endothelial cells from neonatal rat heart were treated with various concentrations of NE for different durations. Apoptosis was assessed by terminal deoxynucleotidyl transferase-mediated nick end-labeling (TUNEL) and DNA fragmentation assays. Caspase activity was measured using specific fluorogenic substrates. Proteins of Bcl-2 family and cytochrome c were assayed by Western blotting. RESULTS: NE induced endothelial apoptosis in a dose- and time-dependent manner. After treatment for 48 h, increasing NE concentration from 5, 10, 50, 100 to 200 microM resulted in 6+/-3%, 14+/-5%, 43+/-4%, 66+/-5%, and 89+/-6% apoptotic cells, respectively. The apoptosis was accompanied by down-regulation of Bcl-2 protein synthesis but not by cytosolic cytochrome c translocation. Caspase-2, -3, -6 and -9 were activated during apoptosis and caspase-2 inhibitor (Z-VDVAD-FMK) and caspase-3 inhibitor (Z-DEVD-FMK) significantly attenuated the apoptosis. Overexpression of Bcl-2 inhibited caspase activity and decreased the apoptosis. Moreover, the NE-mediated apoptotic effect was attenuated by beta- (beta2>beta>beta1) adrenergic antagonists (ICI-118,551>propranolol>atenolol) but was not affected by alpha1- or alpha2-adrenergic antagonists (prazosin or yohimbine). CONCLUSION: Our study is the first report documenting that NE induces apoptosis in neonatal rat endothelial cells mainly through down-regulation of Bcl-2 protein and activation of the beta-adrenergic (beta2>beta1) and caspase-2 pathways. beta-Adrenergic antagonists and caspases inhibitors may be useful in the prevention and management of NE-mediated endothelial apoptosis during heart failure.

Adrenergic beta-Antagonists↗

Prediction of ductus arteriosus closure by neonatal screening echocardiography.

AIMS: We reported the incidence, clinical manifestations and outcome of patent ductus arteriosus (PDA) in full-term infants by screening echocardiography. METHODS AND RESULTS: Total 1230 infants received echocardiographic screening and periodic follow-up. On the third day of life, there were 109 infants with isolated ductus arteriosus aneurysm (DAA), those with persistent patency of the ductus arteriosus (DA) in 26. The DA closed within 48 h in 828 infants, and persisted beyond 48 h in 180. The incidence of PDA in full-term infants was 0.91, 0.83 and 0.66% at 1, 4 and 6 months follow-up, and 0.82, 0.73 and 0.64% if infants with DAA were excluded. Infants with PDA had lower birth body weight (BBW) than those with closed DA (p = 0.02). The DA width on the third day of life ranged from 0.23 to 0.43 cm (0.32+/-0.08 cm) and 0.08 to 0.44 cm (0.16+/-0.06 cm) in infants with or without PDA, respectively, which was significantly different (p < 0.05). The sensitivity, specificity, predictive positive and negative values were 87.5, 92.5, 36.8 and 99% respectively for the cuff-off point at 0.25 cm of DA width. CONCLUSIONS: Risk factors in infants with PDA included lower BBW and larger measured DA width at the third day of life. We predicted the arterial duct would close if DA width <0.25 cm, and suggested follow up earlier if >0.25 cm on the third day of life.

Cardiac Surgical Procedures↗

The different electrophysiological characteristics in children with Wolff-Parkinson-White syndrome between those with and without atrial fibrillation.

Atrioventricular reciprocating tachycardia (AVRT) is known to be the most common supraventricular tachycardias in childhood. Because AF with rapid ventricular response may degenerate to ventricular fibrillation through conduction of accessory pathways (APs), it can be potentially life-threatening in some pediatric patients with WPW syndrome. However, information about WPW syndrome children associated with AF is limited. The purpose of this study was to investigate the specific electrophysiological characteristics in pediatric patients with WPW syndrome and AF. From July 1992 to February 2002, 51 pediatric patients with manifest WPW syndrome and documented AVRT underwent electrophysiological study and radiofrequency catheter ablation. In these patients, two (4%) were found to have several spontaneous episodes of AF recognized on 12-lead standard ECG or 24-hour Holter monitoring. Eleven (22%) patients had AF induced by rapid atrial pacing during the baseline procedure of electrophysiological study. The children with manifest WPW syndrome were divided into two groups: those with AF (group 1; n = 11) consisted of seven male and four female children (mean age 15 +/- 3 years, range 10-18), and those without AF (group 2; n = 40) consisted of 22 boys and 18 girls (mean age 16 +/- 3 years, range 7-18). The study excluded a patient who had Ebstein's anomaly associated with moderate tricuspid regurgitation and right atrial enlargement. The onset and duration of symptoms were not significantly different between the two groups. Comparing the electrophysiological characteristics, the atrial effective refractory period (ERP) was shorter in WPW syndrome children with AF (170 +/- 36 vs 190 +/- 38 ms, P = 0.041). This study demonstrated that the pediatric WPW syndrome patients with AF had different electrophysiological characteristics from those without AF.

Adolescent↗

Prediction of ductus arteriosus closure by neonatal screening echocardiography.

AIMS: We reported the incidence, clinical manifestations and outcome of patent ductus arteriosus (PDA) in full-term infants by screening echocardiography. METHODS AND RESULTS: Total 1230 infants received echocardiographic screening and periodic follow-up. On the third day of life, there were 109 infants with isolated ductus arteriosus aneurysm (DAA), those with persistent patency of the ductus arteriosus (DA) in 26. The DA closed within 48 h in 828 infants, and persisted beyond 48 h in 180. The incidence of PDA in full-term infants was 0.91, 0.83 and 0.66% at 1, 4 and 6 months follow-up, and 0.82, 0.73 and 0.64% if infants with DAA were excluded. Infants with PDA had lower birth body weight (BBW) than those with closed DA (p = 0.02). The DA width on the third day of life ranged from 0.23 to 0.43 cm (0.32 +/- 0.08 cm) and 0.08 to 0.44 cm (0.16 +/- 0.06 cm) in infants with or without PDA, respectively, which was significantly different (p < 0.05). The sensitivity, specificity, predictive positive and negative values were 87.5, 92.5, 36.8 and 99% respectively for the cuff-off point at 0.25 cm of DA width. CONCLUSIONS: Risk factors in infants with PDA included lower BBW and larger measured DA width at the third day of life. We predicted the arterial duct would close if DA width <0.25 cm, and suggested follow up earlier if >0.25 cm on the third day of life.

Aneurysm↗

Pulmonary edema of enterovirus 71 encephalomyelitis is associated with left ventricular failure: implications for treatment.

Epidemics of enterovirus 71 infections caused the rapid death of many children in Malaysia in 1997 and in Taiwan in 1998. Pulmonary edema occurred in most of the fatal cases and was considered to be neurogenic. The role of the heart was rarely investigated before. Between January 1998-January 2001, 34 consecutive patients who were admitted to the intensive care unit due to enterovirus infection were studied prospectively. Patients were divided into two groups: group I with pulmonary edema, and group II without pulmonary edema. Comparisons were made between the two groups based upon demographic, neurological, and cardiovascular manifestations. Group I consisted of 11 patients (5 boys, 6 girls; mean age, 22.8 months), and group II of 23 patients (12 boys, 11 girls; mean age, 28.8 months). There were no significant differences between the two groups in comparing sex, age, body weight, neurological severity, intracranial pressure, cell count, protein and glucose levels in cerebral spinal fluid, and blood pressure. All group I patients had left ventricular dysfunction, and their ejection fractions were significantly lower than those of patients in group II (37 +/- 11% vs. 75 +/- 6%, P < 0.001). Group I heart rates were higher than those of group II (175 +/- 24 vs. 137 +/- 25, P < 0.001). In group I, 9 patients who received conventional treatment died, and the only two survivors received left ventricular assist devices. In conclusion, the pulmonary edema of fulminant enterovirus 71 infection is associated with left ventricular failure. Left ventricular function is the major determinant of outcome. Early recognition of heart failure and aggressive cardiac intervention are life-saving. Pediatr Pulmonol. 2003; 35:263-268.

Child, Preschool↗

Usefulness of Tc-99m HMPAO-labeled WBC heart scan to predict impaired ventricular function and coronary artery dilation in children with Kawasaki disease.

Forty-nine children with Kawasaki disease were included in this study. Based on the severity of carditis as determined by Tc-99m HMPAO-labeled WBC heart scan, the children were separated into two groups. Group A (n=24) had significant carditis and group B (n=25) did not have significant carditis. The left and right ventricular ejection fractions (LVEF and RVEF) were evaluated by equilibrium multigated blood pooling ventriculography. Diameters of the left and right coronary arteries (LCA and RCA) were measured by two-dimensional echocardiography. The results showed that group A had lower LVEF and RVEF, but larger diameters of the LCA and RCA than those of group B patients. The sensitivity of significant carditis to predict left ventricular dysfunction, right ventricular dysfunction, LCA dilation and RCA dilation was 88.9, 70.6, 75, and 71.4%, respectively; the specificities were 100, 100, 100, and 67.9%, respectively. Our findings suggest that significant carditis determined by Tc-99m HMPAO-labeled WBC heart scan can accurately predict impaired ventricular function and coronary artery dilation.

Child, Preschool↗

Flexible endoscopy of aerodigestive tract in small infants.

BACKGROUND: Flexible endoscopy (FE) is a useful method for diagnosing airway problems. Congenital or acquired airway lesions in infants may lead to respiratory distress that requires comprehensive investigation and management. This study was designed to evaluate the use of FE in small infants. METHODS: Infants who had symptoms of respiratory distress and received FE when they were less than 1-year-old were studied and their medical history, diagnoses, interventions, and complications from FE were investigated. RESULTS: The study population consisted of 568 small infants (334 boys and 234 girls) who weighed 5.1 +/- 2.4 kg, and received FE when they were 4.5 +/- 3.6 months of age. Most patients (91.2%) received diagnostic FE and the remainder (8.8%) received therapeutic procedures. Stridor (38.0%) was the most common indication for FE and laryngomalacia (33.3%) was the most frequent finding. Synchronous FE diagnosis was found in 351 (61.8%) cases. No major complications associated with FE were found. CONCLUSION: Flexible endoscopy allows direct visualization of dynamic motion of the small aerodigestive tract. Laryngomalacia was the most common FE finding of respiratory distress in small infants. Synchronous FE lesions were frequently found in this young age group and it necessitated a thorough investigation of the entire aerodigestive tract.

Endoscopy↗

Effects of exogenous surfactant supplementation and partial liquid ventilation on acute lung injury induced by wood smoke inhalation in newborn piglets.

OBJECTIVE: To investigate the beneficial effects of exogenous surfactant supplementation (ESS) and partial liquid ventilation (PLV) in treating acute lung injury induced by wood smoke inhalation. DESIGN: A prospective, randomized, controlled, multigroup study. SETTING: An animal research laboratory at a medical center. SUBJECTS: Newborn piglets (n = 29; 1.80 +/- 0.06 kg) of either sex. INTERVENTIONS: Animals were ventilated with a tidal volume of 15 mL/kg, a rate of 30 breaths/min, a positive end-expiratory pressure of 5 cm H(2)O, and an Fio(2) of 1.0. After the induction of acute lung injury by wood smoke inhalation, animals were randomly assigned to receive either conventional mechanical ventilation (CMV) or PLV with or without ESS pretreatment. Animals were grouped as CMV, ESS-CMV, PLV, and ESS-PLV. MEASUREMENTS AND MAIN RESULTS: Arterial blood gases, cardiovascular hemodynamics, dynamic lung compliance, and total lung injury scores were measured. After smoke inhalation, all four groups displayed similar high arterial carboxyhemoglobin levels, low Pao(2) (<150 mm Hg), and low dynamic lung compliance (<66% of its baseline). In the CMV group, these deleterious conditions remained during the 4-hr observation period, and severe lung injury was noted histologically. All treatment groups demonstrated a significant increase in Pao(2) compared with the CMV group. In addition, both the PLV and ESS-PLV groups displayed significant improvements in dynamic lung compliance and in their histologic outcomes. Nevertheless, none of the variables measured in the PLV group differed from those measured in the ESS-PLV group. CONCLUSIONS: In a newborn piglet model of smoke inhalation injury, PLV or ESS improved oxygenation. PLV compared favorably with ESS in its greater improvements in lung compliance and lung pathology. However, the combined therapy of ESS and PLV was not clearly superior to PLV alone during the observation period.

Acute Disease↗

Influence of ductal size on the results of transcatheter closure of patent ductus arteriosus with coils.

To assess the influence of ductal size on the results of transcatheter closure of patent ductus arteriosus (PDA) with coils, 154 consecutive patients were studied prospectively. Ductal size was defined as the narrowest diameter of ductus measured on aortography. All patients were divided into 5 groups according to ductal size: < 1 mm, 1-1.9 mm, 2-2.9 mm, 3-3.9 mm, and > or = 4 mm. The occlusion of PDA with coils was performed through a transarterial approach. The results were evaluated by angiography at 10 minutes and by color Doppler echocardiography at 1 day, 2 days, 1 week, 1 month, 3 months, 6 months, and 12 months after the procedure. The immediate occlusion rates for ductal sizes < 1 mm, 1-1.9 mm, 2-2.9 mm, 3-3.9 mm, and > or = 4 mm were 89.7%. 75.4%, 51.4%, 30.8%, and 40%, respectively; whereas the occlusion rates at 12-months follow-up were 100%, 98.5%, 97.3%, 69.2%, and 80%, respectively. There were no significant differences in occlusion rate at 12-months follow-up among the groups with ductal sizes < 3 mm or among the groups with ductal sizes > or = 3 mm. The occlusion rate for ductal size < 3 mm at each follow-up time was significantly higher than that for ductal size > or = 3 mm (10 minutes: 71.8% vs 34.8%. P = 0.001; 12-months: 98.5% vs 73.9%, P < 0.001). The occlusion rate of residual shuntings at 12-months follow-up for ductal size < 3 mm was also significantly higher than that for ductal size > or = 3 mm (94.6% vs 60%, P = 0.007). The results of the present study demonstrate that ductal size < 3 mm had a higher occlusion rate than that for a size > or = 3 mm. PDA with a size > or = 3 mm may need other treatment strategies or other devices to achieve better results.

Cardiac Catheterization↗