The purpose of this study was to assess whether the magnitude of change in aerobic power was different in boys (mean age 10.25 +/- 0.50 y) who followed a high-intensity interval training protocol, compared to those who followed a moderate-intensity continuous training protocol. Boys were assigned to either a control group (n = 15), a continuous training group (n = 10), or an interval training group (n = 10). They completed peak oxygen uptake tests at baseline and following an 8-week training period. The control group continued with normal activity habits, whilst the continuous training group followed a 20-minute steady-state cycle protocol at 80-85% of the maximal heart rate, and the interval training group completed 30-s sprints on a cycle ergometer, interspersed with active rest periods. The two training protocols were designed to incur similar cardiovascular work over the 20 minutes of each training session. Significant increases (p < 0.05) in peak oxygen uptake were noted for both the interval and continuous training groups. The interval training group showed marked pre- to post-increases in both peak oxygen pulse, oxygen pulse at the ventilatory threshold, and ventilatory threshold that were not apparent in the continuous group boys. It would appear that a high-intensity interval protocol confers a different training effect in comparison to continuous steady-state training in boys. Possible mechanisms that underpin these adaptations may include increased blood volume and a concomitant adjustment in stroke volume.

Objectives: To use dobutamine stress echocardiography to determine left ventricular (LV) function and wall motion of children long term after arterial switch operation (ASO) for transposition of the great arteries. Design and patients: 31 patients (24 boys) with ASO performed at a mean (SD) of 15.5 (4.3) days of life were studied at an age of 9.4 (2.0) years. All had normal coronary angiographic findings. LV echocardiographic indexes, including fractional shortening, ejection fraction, rate corrected velocity of circumferential fibre shortening (VCFc), and wall stress, as well as LV wall motion abnormalities were determined at rest and under dobutamine stress. The results were compared with those of 20 healthy age matched control participants. Setting: Tertiary paediatric cardiac centre. Results: Fractional shortening, ejection fraction, and VCFc were significantly lower in patients than in controls at rest (all with p < 0.001). Stress–velocity index detected impaired LV contractility in 19 (61%) patients at rest. An older age at operation (p = 0.01), longer bypass (p = 0.01) and circulatory arrest times (p = 0.045), and an unusual coronary artery pattern (p = 0.059) were associated with impaired resting LV contractility. Dobutamine stress echocardiography unmasked wall motion abnormalities in 23 (74%) patients. Exercise myocardial perfusion scan, performed in 22 patients, showed reversible myocardial perfusion defects in 17. These defects corresponded to segments of hypokinesia as detected by dobutamine stress echocardiography. Conclusion: A significant proportion of children, albeit asymptomatic, had impaired baseline LV contractility and reversible myocardial perfusion defects and mild wall motion abnormalities on stress after ASO.

This cross‐sectional study was designed to provide baseline information on peak oxygen uptake for Southern Chinese children in relation to age and sexual maturation. Sixty‐three boys and 84 girls, classified for stage of sexual maturation using Tanner's stages, successfully completed a peak oxygen uptake test. ANOVA was used to examine differences in absolute and mass‐related peak VO 2 . The least‐squares log‐linear relationship between mass and peak VO 2 was examined using analysis of covariance. We found no difference between boys' and girls' peak VO 2 prior to puberty. Absolute peak VO 2 values for under‐10‐year‐old Chinese girls and boys were 17% and 19%, respectively, lower than Caucasian predicted values. Log‐linear adjusted means for prepubertal boys and girls were 34% and 33% lower than Caucasian boys and girls, respectively. By adolescence, values were comparable to Caucasian values. South Chinese children show a distinct pattern of development relative to Caucasian children, particularly in the younger age groups. Am. J. Hum. Biol. 16:602–605, 2004. © 2004 Wiley‐Liss, Inc.

OBJECTIVE:Western infants with congenital heart disease have frequently been reported to have a low birthweight for gestational age. Studies in Asian infants seem to be lacking in this area. This is the first extensive study presenting the birthweight distribution of Chinese newborns with symptomatic congenital heart disease. METHODS:The birth data of 454, mainly southern-Chinese infants with symptomatic cardiovascular defects, born between 1990 and 1995 and admitted to Grantham Hospital, Hong Kong in 1994 and 1995, were analysed retrospectively. Infants with (non)-genetic syndromes or other major extracardiac malformations were excluded. RESULTS:Fifteen per cent of all newborns had a birthweight below the reference mean of - 2 Z-score. After correction for length of gestation, no significant difference could be detected in birthweight between the cyanotic and acyanotic groups, nor between the different haemodynamic disturbances. Infants with atrial or ventricular septal defects, tetralogy of Fallot, pulmonary atresia with ventricular septal defect, heart with univentricular atrio-ventricular connection or double outlet right ventricle showed significant birthweight deficits. Transposition of the great arteries was not related to being small for gestational age. CONCLUSIONS:Similar to Western infants, prenatal growth impairment was a common feature in Chinese infants with symptomatic congenital heart disease. The birthweight distribution in Chinese might be comparable to that in Western populations. Exceptions are possibly the high frequency of low birthweight in Chinese newborns with atrial septal defect or a single-ventricle abnormality. Further studies on fetal anthropometry and haemodynamics are necessary to provide insight into the relation between cardiovascular malformations and being small for gestational age.

Myocardial iron deposition, among other factors, contributes to left ventricular (LV) dysfunction in patients with β thalassaemia major.1 Nonetheless, conventional indices have not been particularly useful for its early detection. Importantly, cardiac function deteriorates rapidly once clinical symptoms develop. Dobutamine stress echocardiography (DSE) is well accepted in the evaluation of myocardial dysfunction caused by coronary artery disease in adults.2 In children, DSE has been used for early detection of LV dysfunction in long term childhood cancer survivors.3 In this study, we assessed the usefulness of DSE for early detection of LV dysfunction in thalassaemia patients. Twenty six patients (17 females) with β thalassaemia major with a mean (SD) age of 17.4 (8.3) years (range 4–33 years) were studied. Their body surface area (BSA) was 1.12 (0.20) m2. None had congestive heart failure clinically and all were in New York Heart Association (NYHA) functional class I at initial assessment. Monthly blood transfusion was started at a median of 11 months (range 3–96 months), while desferrioxamine was started at a median age of 30 months (range 25–114 months). Post-transfusion haemoglobin was targeted at 14 g/dl (8.7 mmol/l), and echocardiographic studies were performed within one week of transfusion to minimise confounding influence of anaemia. Only one of the patients had undergone splenectomy. Twenty healthy subjects (13 females) aged 10.4 (4.5) years (range 4–15 …

The presence of ventriculo-coronary arterial communications tended to predict the need for shunting despite successful laser-assisted valvotomy and balloon valvo-plasty for pulmonary atresia with intact ventricular septum. Although growth of the right ventricular inlet and outlet occurs after a successful procedure, tricuspid annulus growth lagged behind the somatic growth.

We assessed the spectrum of airway disorders in children with congenital cardiac anomalies, and reviewed our experience in using flexible bronchoscopy for assessment of airway problems in this patient group. The clinical records, flexible bronchoscopic findings, and cardiac imaging results of pediatric cardiac patients who presented with either clinical or radiological signs of airway obstruction between 1992-1999 were reviewed. Flexible bronchoscopic assessment was performed with the patients under sedation and topical anesthesia, using one of two bronchoscopes, i.e., an Olympus BFN20 or Olympus BF3C20. Of a total of 52 patients, 33 had acyanotic cardiovascular lesions, the commonest being left-to-right shunts (61%), while 19 had cyanotic heart lesions, with right ventricular outflow obstruction being the commonest (63%). Twenty-seven patients had undergone either surgical or transcatheter interventions. The median age at bronchoscopic assessment was 6 months (range, 4 days to 6 years). None of the patients developed significant procedural complications. A definitive diagnosis was made in 48 (92%) patients, 8 of whom had abnormalities involving only the upper airways, 35 only the lower airways, and 5 both. Abnormalities of the upper airway included laryngomalacia (n = 6), subglottic stenosis (n = 3), pharyngeal collapse (n = 2), and 1 each of choanal stenosis and supraglottitis. Extrinsic compression was the commonest lower airway abnormality that was found in 27/40 patients (67%), with a predilection for the left main bronchus (18/27, 67%). The structures that caused extrinsic compression included dilated pulmonary arteries with or without left atrial dilation (n = 20), an anomalous aortic or pulmonary arterial course (n = 3), a dilated aorta (n = 1), and a shunt (n = 1), but were not obvious in 2 patients. Intrinsic lower airway abnormalities included bronchomalacia (n = 4), tracheal stenosis (n = 4), and one each of variant bronchial bifurcation and a pouch arising from the tracheal wall. Intraluminal mucus plugging of the lower airways occurred in the remaining 3 patients. Children with congenital heart disease are at risk of airway obstruction both before and after surgery. Flexible bronchoscopy, being safe and effective in diagnosing airway disorders in this patient group, should be considered as the first line of investigation.

Objective: We report our experience in combining tracheobronchography and angiocardiography in the assessment of a selected cohort of paediatric cardiac patients with problematic airway disorders.Methodology: The clinical records of 11 patients who underwent 17 studies at a median age of 5.5 months (range 3 months to 10.8 years) were reviewed. Tracheobronchography and angiocardiography were performed under general anaesthesia using a non-ionic contrast agent. The findings were compared with those of flexible bronchoscopy and magnetic resonance imaging (MRI).Results: Seven patients had cardiac lesions associated with vascular anomalies potentially compressing the airway, while four had no identifiable aberrant or enlarged vessels. All examinations but one were performed without complications. Tracheobronchography demonstrated extrinsic vascular compression with secondary airway malacia in three (27%), intrinsic tracheobronchial stenosis in five (45%), and airway malacia in three patients (27%). Precise measurement of the airway calibre and real-time fluoroscopic monitoring facilitated transcatheter tracheobronchial interventions (six balloon dilations, three stent implantations) in four patients. In conjunction with angiocardiography, cine-tracheobronchography provided detailed information on the spatial relationship between vascular and airway structures in all patients; allowed dynamic assessment of airway malacia; and facilitated preoperative planning in six patients. In contrast, bronchoscopy failed to differentiate malacia from extrinsic compression in four patients (36%), while MRI, performed in six patients, was unsatisfactory in one due to a motion artefact and failed to diagnose airway malacia and extrinsic compression in three patients.Conclusions: Tracheobronchography is relatively safe in paediatric cardiac patients. Combined tracheobronchography and angiocardiography, a less operator-dependent imaging modality compared to bronchoscopy and MRI, delineated the airway and vascular anatomy in detail; facilitated preoperative planning; and permitted transcatheter tracheo-bronchial interventions. The dynamic capability of tracheobronchography supplements that of flexible bronchoscopy and MRI in the diagnosis of airway malacia.

Objective: To compare the outcome of infants and children who have right atrial isomerism and normal pulmonary venous drainage with those who have anomalous drainage, and to determine factors associated with poor outcome. Design and patients: Retrospective review of management and outcome of 116 infants and children determined to have right atrial isomerism between January 1980 and December 2000. Setting: Tertiary paediatric cardiac centre. Results: The 116 patients presented at a median of one day (range 1 day to 3.7 years) with cyanosis in the majority (96%). No interventions were planned in 31 (27%) patients, all of whom died. The early surgical mortality for pulmonary venous repair was 25% (2 of 8), Fontan procedure 26% (5 of 19), cavopulmonary shunting 7.7% (1 of 13), and systemic pulmonary arterial shunt insertion 1.9% (1 of 53). Late mortality was related to infection (n = 10), sudden death of unknown aetiology (n = 7, 5 with history of arrhythmia), and documented arrhythmia (n = 1). Patients with obstructed anomalous pulmonary venous drainage had the worst survival (p < 0.001). The mean (SEM) survival estimates for those with normal pulmonary venous drainage at 1, 5, 10, and 15 years was 81 (5.3)%, 67 (6.6)%, 60 (7.8)%, and 43 (12)%, respectively, similar to those for patients with non-obstructed anomalous drainage (p = 0.06). Independent risk factors for mortality included pulmonary venous obstruction (relative risk 3.8, p = 0.001) and a single ventricle (relative risk 2.9, p = 0.016). An analysis of only patients with normal pulmonary venous drainage identified no risk factors for mortality. Conclusions: The long term outcome of infants and children with right atrial isomerism in association with a normal pulmonary venous drainage remains unfavourable. Sepsis and sudden death that may potentially be related to cardiac arrhythmia are major causes of late mortality.

A 20-year-old young man suffered from severe protein-losing enteropathy 4 years after Fontan operation. His postoperative haemodynamics were unfavourable in terms of poor myocardial contractility and moderate atrioventricular prosthetic paravalvar leakage. A 2-week trial of steroid therapy for protein-losing enteropathy was given without success. The clinical course was complicated by Legionella pneumophila pneumonia and bacteraemia, which respond to the combination therapy with intravenous erythromycin and ciprofloxacin. The vulnerability of the patient to infection was related to an immuno-deficiency state secondary to protein-losing enteropathy and steroid therapy. Steroids should be used with caution in the management of protein-losing enteropathy after Fontan operation.

BACKGROUND Different types of coils have been designed for transcatheter closure of persistent arterial ducts. We compared the efficacy and safety of three types of coils: Gianturco coils (Cook), Cook detachable coils (Cook), and Duct Occlud devices (pfm). METHODS Sixty-three patients underwent coil occlusion of arterial ducts between April 1995 and July 2000. The mean age and weight were 4.8+/-3.4 years and 16.5+/-7.6 kg, respectively. The results and complications of ductal occlusion among the three types of coils were compared. Kaplan-Meier analysis was used to assess reduction in the prevalence of residual shunt with time, and multiple regression analysis was performed to identify predictors of complete occlusion. RESULTS Coil occlusion of persistent arterial ducts that measured 2. 2 +/- 0.8 mm was feasible in 90% (57/63) of patients. Gianturco coils were used in 29, Duct Occlud devices in 16, and Cook detachable coils in 12 patients. The prevalence of residual shunt at 24 hours, 6 months, 12 months, and 24 months was 42%, 20%, 18%, and 14%, respectively. The reduction in prevalence of residual shunt with time tended to be greater when Gianturco coils were used (P =. 067). Logistic regression identified the use of Gianturco coils to be a significant predictor of complete ductal occlusion on follow-up (P =.04). Pull-through of coils occurred in 4.8% (3/63) and coil embolization in 6.3% (4/63). There was no association between the type of coil and the risk of embolization (P = 1.00). CONCLUSIONS Transcatheter occlusion of small persistent arterial ducts with coils is safe and effective. There is no advantage of detachable coils (Cook detachable coils and Duct Occlud devices) over nondetachable Gianturco coils in reducing the risk of embolization. Our findings are in favor of the inexpensive, but more effective, Gianturco coils for occluding small arterial ducts of 3 mm or less.

Objective-To study and compare the eVects of mental and physical stress on long QT syndrome (LQTS) patients.Design-Case-control study.Main outcome measures-QT intervals were measured from lead V3.Serum potassium and plasma catecholamine concentrations were also monitored.Patients-16 patients with type 1 LQTS (LQT1), 14 with type 2 LQTS (LQT2), both groups asymptomatic, and 14 healthy control subjects.Interventions-Three types of mental stress tests and a submaximal exercise stress test.Results-Heart rate responses to mental stress and exercise were similar in all groups.During mental stress, the mean QT interval shortened to a similar extent in controls (-29 ms), LQT1 patients (-34 ms), and LQT2 patients (-30 ms).During exercise, the corresponding QT adaptation to exercise stress was more pronounced (p < 0.01) in healthy controls (-47 ms) than in LQT1 (-38 ms) or LQT2 patients (-38 ms).During exercise changes in serum potassium concentrations were correlated to changes in QT intervals in controls, but not in LQTS patients.LQT1 and LQT2 patients did not diVer in serum potassium, catecholamine or heart rate responses to mental or physical stress.Conclusions-QT adaptation to mental and exercise stress in healthy people and in patients with LQTS is diVerent.In healthy people QT adaptation is more sensitive to physical than to mental stress while no such diverging pattern was seen in asymptomatic LQTS patients.

Two infants who developed chylothorax after surgery for congenital heart disease were treated successfully with subcutaneous octreotide. Apart from reducing chyle output, octreotide decreased the triglyceride content of the pleural fluid.

Subarterial ventricular septal defect (VSD) is relatively common in Orientals. We reviewed the outcome of 214 patients (137 males) who were followed for 8.6 ± 5.2 years (range 0.1 to 24.3) and addressed the issue regarding the necessity and optimum timing of closing subarterial defects before development of aortic valve deformities. Demographic data, transthoracic and transesophageal echocardiographic findings, cardiac catheterization results, and operative findings were reviewed. Kaplan-Meier actuarial analysis was performed to assess the development of aortic valve complications over time. Seventy-five patients with heart failure and pulmonary hypertension underwent surgical closure of VSD at the age of 2.4 ± 2.9 years. No patient had aortic cusp prolapse before operation and none developed aortic cusp prolapse or aortic regurgitation (AR) on follow-up. In contrast, of the 139 asymptomatic patients managed conservatively, 102 (73%) developed aortic cusp prolapse, 78% of whom (80 of 102) developed AR. The prevalence of aortic cusp prolapse and AR at 1, 5, 10, and 15 years old was 8%, 30%, 64%, and 83%, and 3%, 24%, 45%, and 64%, respectively. Significant prolapse or AR prompted surgical closure of VSD with (n = 22) or without (n = 26) valvoplasty in 48 of 102 patients (47%). The size of the VSD was significantly larger in patients with heart failure (9.6 ± 3.3 mm) or aortic cusp prolapse (11.7 ± 4.1 mm) compared with those without heart failure (4.5 ± 1.4 mm, p <0.001). All patients with aortic cusp prolapse and all but 1 with heart failure had a defect size of ≥5 mm. In conclusion, subarterial VSD of ≥5 mm should be closed as early as possible to prevent development of aortic cusp prolapse and AR. Asymptomatic patients with small defects <5 mm could be managed conservatively.

A 15-year-old girl with Noonan syndrome, intestinal lymphangiectasia and severe valvar pulmonary stenosis had an abnormal lymphangioscintigram that showed intense activity in the inguinal regions bilaterally. Cutaneous oozing of lymphatic fluid from the groin wound complicated percutaneous balloon pulmonary valvoplasty. This previously unreported complication highlights the risk of damage to abnormal lymphatic channels in patients with Noonan syndrome who undergo interventional catheterization.

Double-outlet right ventricle with intact ventricular septum is exceedingly rare [ 1 Accorsi F. Thiene G. Double-outlet right ventricle with intact ventricular septum. Case report, review of the literature and proposed pathogenetic interpretation. G Ital Cardiol. 1985; 15: 232-237 Google Scholar , 2 Ikemoto Y. Nogi S. Teraguchi M. Imamura H. Kobayashi Y. Double-outlet right ventricle with intact ventricular septum. Acta Paediatr Jpn. 1997; 39: 223-226 Google Scholar ]. We report on an association of this rare congenital heart malformation with left ventriculo-coronary communications that has not been described previously.

Racial group studies have identified differences in the occurrence of congenital heart disease (CHD) among ethnic populations. The aim of this study was to characterize the proportionate frequency and clinical profile of children with symptomatic cardiac abnormalities in Hong Kong. The hospital records of 666, mainly Southern Chinese children with symptomatic CHD, who were 4 years of age or younger and who were admitted to Grantham Hospital, Hong Kong, in 1994 and 1995 were analyzed retrospectively. Left-to-right shunting (45.0%) and pulmonary outflow obstruction (34.4%) were the most frequently diagnosed categories, followed by left ventricular outflow obstruction (8.3%), transposition of the great arteries (4.2%), conditions with intracardiac mixing (3.9%), and other cardiac lesions (4.2%). Compared with Western studies, pulmonary outflow obstruction (p < 0.0001), particularly tetralogy of Fallot and critical pulmonary stenosis, were more frequent in Chinese children. In contrast with previous reports, coarctation of the aorta (5%) does not seem to be uncommon in Chinese patients. Conversely, aortic stenosis and hypoplastic left ventricle may be rare in these children (1% vs 3% and 3–7%). Other cardiac lesions showed no consistent racial difference in the frequency of occurrence. Chinese patients with Down's syndrome had ventricular septal defect (38%) as the predominant lesion followed by atrioventricular septal defect (25%). Western studies usually report a reverse pattern for these two lesions. The mortality rate for the total cohort was 7.5%. However, of those with conditions with intracardiac mixing and left ventricular outflow tract obstruction many did not survive childhood (20% and 21%, respectively).