Prenatal Diagnosis of Single Ventricle Physiology Impacts on Cardiac Morbidity and Mortality.

We sought to evaluate the impact of prenatal diagnosis on morbidity and mortality in single ventricle (SV) lesions. All consecutive patients with pre- or postnatally diagnosed SV physiology admitted to our centre between January 2001 and June 2013 were reviewed. Primary endpoints included survival until 30 days after bidirectional cavopulmonary connection (BCPC) without transplant or BCPC takedown. Prenatal diagnosis was performed in 160 of 259 cases (62%). After excluding all cases with termination of pregnancy, intrauterine demise or treated with comfort care, a total of 180 neonates were admitted to our centre for treatment, including 87 with a prenatal and 93 with a postnatal diagnosis. Both groups showed similar distribution regarding diagnosis, dominant ventricle and risk factors such as restrictive foramen or some form of atrial isomerism. A larger proportion of postnatally diagnosed children presented at admission with elevated lactate > 10 mmol/l (p = 0.02), a higher dose of prostaglandin (p = 0.0013) and need for mechanical ventilation (p < 0.0001). Critical lesions such as hypoplastic left heart syndrome were an important determinant for morbidity and mortality. Thirty-days survival after BCPC was better in patients with prenatal diagnosis (p = 0.025). Prenatal diagnosis is associated with higher survival in neonates with SV physiology.

Reference values for the 6-minute walk test in healthy children and adolescents in Switzerland.

BACKGROUND: The six-minute walk test (6MWT) is a simple, low tech, safe and well established, self-paced assessment tool to quantify functional exercise capacity in adults. The definition of normal 6MWT in children is especially demanding since not only parameters like height, weight and ethnical background influence the measurement, but may be as crucial as age and the developmental stage. The aim of this study is establishing reference values for the 6MWT in healthy children and adolescents in Switzerland and to investigate the influence of age, anthropometrics, heart rate, blood pressure and physical activity on the distance walked. METHODS: Children and adolescents between 5-17 years performed a 6MWT. Short questionnaire assessments about their health state and physical activities. anthropometrics and vitals were measured before and after a 6-minute walk test and were previously defined as secondary outcomes. RESULTS: Age, height, weight and the heart rate after the 6MWT all predicted the distance walked according to different regression models: age was the best single predictor and mostly influenced walk distance in younger age, anthropometrics were more important in adolescents and females. Heart rate after the 6MWT was an important distance predictor in addition to age and outreached anthropometrics in the majority of subgroups assessed. CONCLUSIONS: The 6MWT in children and adolescents is feasible and practical. The 6MWT distance depends mainly on age; however, heart rate after the 6MWT, height and weight significantly add information and should be taken into account mainly in adolescents. Reference equations allow predicting 6-minute walk test distance and may help to better assess and compare outcomes in young patients with cardiovascular and respiratory diseases and are highly warranted for different populations.

Plasma B-type natriuretic peptide levels in children with heart disease.

AIM: To determine plasma B-type natriuretic peptide (BNP) levels in children with heart diseases before medical or surgical treatment for monitoring therapeutic efficacy in an observational prospective clinical trial at tertiary care centre. METHODS: In 522 paediatric patients at an age of 6.4 ± 5.2 years (mean ± SD; range: 14 days-18 years) with congenital heart disease (CHD), cardiomyopathies (CMP) or pulmonary arterial hypertension (PAH), plasma BNP levels were evaluated before and under treatment. RESULTS: Most types of heart disease are associated with increased mean plasma BNP levels before treatment, with highest values in children with CMP (BNP 6165 pg/mL in dilated CMP vs. 817 pg/mL in hypertrophic, vs. 1236 pg/mL in restrictive CMP, each p < 0.05). Children with PAH showed a significant decrease in BNP levels under medical treatment (mean BNP 981 pg/mL before vs. 26 pg/mL under treatment, p < 0.05). Children with univentricular CHD undergoing surgical staged palliation showed a significant decrease in BNP levels after bidirectional cavopulmonary anastomosis (BDCP) (BNP 109 pg/mL before vs. 70 pg/mL after BDCP, p < 0.05). CONCLUSION: Plasma BNP levels are elevated in children with heart disease before treatment and are a useful laboratory parameter under treatment during long-term follow-up.

Self-monitoring of oral anticoagulation therapy in children.

This study aimed to investigate the accuracy of home International Normalized Ratio (INR) self-monitoring in pediatric patients on long-term oral anticoagulation therapy. Statistical and clinical agreement of INR values from capillary whole blood samples measured by 2 different portable prothrombin time monitors (CoaguChek S and XS) and venous blood samples measured by a laboratory coagulation analyzer were evaluated using the Bland-Altman analysis. Eighty-three INR comparisons (56 using the CoaguChek S and 27 using the CoaguChek XS) were obtained from 35 children aged 4 months to 18 years. Mean differences between venous and capillary INR values and their limits of agreement were -0.04 (-0.63 to 0.55) overall, 0.006 (-0.63 to 0.65) for the CoaguChek S and -0.13 (-0.57 to 0.31) for the CoaguChek XS. The Pearson correlation coefficients were 0.88 overall, 0.84 for the CoaguChek S and 0.95 for the CoaguChek XS. Expanded and narrow agreements for all patients were 97.6 and 94%, respectively. In conclusion, home INR self-monitoring is accurate for children requiring long-term oral anticoagulation therapy. Our data suggest that INR self-monitoring with the newer CoaguChek XS is more accurate than with the older CoaguChek S monitor.

Risk factors for reoperation after relief of congenital subaortic stenosis.

BACKGROUND: Congenital subaortic stenosis entails a lesion spectrum, ranging from an isolated obstructive membrane, to complex tunnel narrowing of the left outflow associated with other cardiac defects. We review our experience with this anomaly, and analyze risk factors leading to restenosis requiring reoperation. METHODS: From 1994 to 2006, 58 children (median age 4.3 years, range 7 days-13.7 years) underwent primary relief of subaortic stenosis. Patients were divided into simple lesions (n=43) or complex stenosis (n=15) associated with other major cardiac defects. Age, pre- and postoperative gradient over the left outflow, associated aortic or mitral valve insufficiency, chromosomal anomalies, arteria lusoria, and operative technique (membrane resection (22) vs associated myectomy (34) vs Konno (2)) were analyzed as risk factors for reoperation (Kaplan-Meier, Cox regression). RESULTS: There was no operative mortality. Median follow-up spanned 2.7 years (range 0.1-10), with one late death at 4 months. Reoperation was required for recurrent stenosis in 11 patients (19%) at 2.6 years (range 0.3-7.5) after initial surgery. Risk factors for reoperation included complex subaortic stenosis (p=0.003), younger age (p=0.012), postoperative residual gradient (p=0.019), and the presence of an arteria lusoria (p=0.014). For simple lesions, no variable achieved significance for stenosis recurrence. CONCLUSIONS: Surgical relief of congenital subaortic stenosis, even with complex defects, yields excellent results. Reoperation is not infrequent, and should be anticipated with younger age at operation, complex defects, residual postoperative gradient, and an arteria lusoria. Myectomy concomitant to membrane resection, even in simple lesions, does not provide enhanced freedom from reoperation, and should be tailored to anatomic findings.

The Swiss registry for pulmonary arterial hypertension: the paediatric experience.

BACKGROUND: Pulmonary arterial hypertension is a rare disease with a poor prognosis. Epidemiological data are scarce, particularly in the paediatric population. A registry was recently developed in order to collect epidemiological data on patients with pulmonary arterial hypertension (PAH) in Switzerland. This is the first description of the paediatric data. METHODS: Paediatric patients aged 0-18 years with the diagnosis of PAH were enrolled in the registry from 1999 to 2005 with informed consent from their parents. Patient characteristics, PAH aetiology, functional capacity, exercise capacity, treatments and outcome were among the most important data collected. RESULTS: A total of 23 patients (12 male, 11 female) have been thus far included in the registry. Median age at time of diagnosis was 3 years (range 1 month-18 years) and median follow-up was 3.47 years (range 1 day-12.6 years). PAH aetiologies are diagnosed as idiopathic in 8/23 patients (34.8%) and associated with congenital heart diseases in 12/23 (52.2%) or with pulmonary diseases in 3/23 patients (13.0%). Death occurred in 1 patient before treatment was initiated. Single treatments include medications with a calcium channel blocker in 2/23 patients, with bosentan in 10/23, and with inhaled iloprost in 1/23. Combined therapies include bosentan and inhaled iloprost in 7/23 patients, bosentan and sildenafil in 2/23 patients, and bosentan, sildenafil and inhaled iloprost in 2/23 patients. Additional oral anticoagulation is given to 14/23 patients and 8/23 patients are on oxygen therapy. NYHA class at baseline visit was obtained in 22/23 patients (4 NYHA 2, 17 NYHA 3 and 1 NYHA 4). Changes in NYHA class were observed over a 2-year period in 3/22 patients who improved from NYHA 3 to NYHA 2. Initial improvement of 6-minute walk distance was observed in 6/13 patients with a sustained improvement in 4. CONCLUSION: These preliminary results provide information on the epidemiology of PAH in children in Switzerland and demonstrate that most paediatric patients show stabilisation of the disease under new treatments. This underscores the utility of registries for rare diseases in providing crucial information in the era of new therapies. It may also help to improve the future medical approach.

Siblings with infantile cerebral stroke and delayed multivessel involvement--a new hereditary vasculopathy?

We describe an unusual vasculopathy in two sisters of non-consanguineous parents. The first child developed an acute hemiparesis and focal seizures at the age of 6 months during a febrile illness. Magnetic resonance imaging (MRI) of the brain showed bilateral cortical-subcortical infarction not confined to a vascular territory. Subsequently, the child had a persistent stable neurological deficit. Her younger sister had a similar encephalitis-like episode at the age of 4 months, with left-sided cortical-subcortical ischaemic lesions. Two months later she had left-sided focal seizures. MRI showed a right-sided cortical enhancement, magnetic resonance angiography (MRA) was normal. The neurological deficit was stable and she was seizure free. These episodes were initially interpreted as metabolic strokes, but work-up was normal and mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes (MELAS) was excluded. In their teens both sisters were diagnosed with pulmonary and systemic hypertension and, due to the arterial hypertension, myocardial hypertrophy. Renal artery stenosis, pathological pulmonary arteries, and stenosis and rarefication of coronary arteries were found; the aorta and retinal vessels were normal. Repeat cranial MRI and MRA showed multiple collaterals, while the carotid and basilar arteries were extremely narrowed (moyamoya appearance). We suggest the diagnosis is a hereditary systemic vasculopathy of unknown origin.

Traumatic free wall and ventricular septal rupture - 'hybrid' management in a child.

A 8-year-old boy showed a traumatic ventricular septal rupture following a blunt chest trauma, and was scheduled for elective catheter closure. Two weeks later, a follow-up echocardiogram revealed a pseudoaneurysm of the anterior wall of the left ventricle. Because of the apical location of the VSD, it was decided to proceed with transcatheter occlusion. After successful VSD closure, the patient was taken to the operation room for surgical repair of the left ventricular pseudoaneurysm. Symptoms and signs seen in patients with ventricular pseudoaneurysms appear to be discrete and variable, and a high clinical index of suspicion with a very close echocardiographic follow-up is strongly recommended after occurrence of a blunt cardiac trauma. The combined 'hybrid' approach of transcatheter closure of the intraventricular rupture followed by surgical closure of the pseudoaneurysm allows for a less invasive and efficient management of this rare combination of post-traumatic ventricular free wall and septal rupture in a child.

Impact of right ventricular size on ECG after percutaneous closure of atrial septal defect with Amplatzer Septal Occluder.

OBJECTIVES: To assess ECG changes after percutaneous atrial septal defect (ASD) closure in children with significant left-to-right shunt. METHODS: Analysis of data of 36 consecutive children with an ASD who had successful percutaneous ASD closure with an Amplatzer Septal Occluder. Assessment comprised echocardiography and ECG the day before and after the procedure and at 1, 6 and 12 months follow-up. RESULTS: The median age (interquartile range) of children was 7.3 (5.3) years. On the day after the procedure the end diastolic diameter of the right ventricle showed already a diminution (34 (12) mm/m2 before intervention vs. 32 (12) mm/m2). ECG changes were first observed at 1 month follow-up (PR interval before intervention 139 (20) ms vs. 132 (20) ms; QRS duration 88 (18) ms vs. 82 (19) ms) and at 6 months follow-up (QRS axis 77 degrees (33) before intervention vs. 72 degrees (53)). With the exception of the QRS duration, ECG intervals and axis were in a normal range in all patients before the procedure. Median QRS duration normalised at 1 year follow-up (83 (8) ms). CONCLUSION: After transcatheter ASD closure, decrease in right ventricular size began rapidly and was followed by reduction of the QRS duration and PR interval within weeks. Shifting to the left of the QRS axis was observed within 6 months follow-up. This study showed that ECG changes due to right ventricular volume overload can regress and normalise after percutaneous ASD closure in children.

Early clinical results of the telemetric adjustable pulmonary artery banding FloWatch-PAB.

BACKGROUND: Adjustment of pulmonary artery banding (PAB) may be a challenging procedure in complex congenital heart defects. Whatever the technique used, subsequent re-operations are frequently needed to control the pulmonary blood flow or pressures. OBJECTIVE: To report the efficacy of a new telemetric adjustable PAB (FloWatch-PAB) operated with the help of an external control unit that transmits to the implant energy and commands to further narrow or release the pulmonary artery using radiofrequency waves. METHODS AND RESULTS: In a multicenter, prospective, nonrandomized, single-arm clinical investigation, 13 children (median age, 4.5 months; range, 6 days to 11 years; median weight, 4.2 kg; range, 3.1 to 27 kg) underwent implantation of the FloWatch-PAB through median sternotomy in 8 and left thoracotomy in 5. The diagnosis was multiple ventricular septal (VSD) defects with complex anatomy in 3, single ventricle without pulmonary stenosis in 2, VSD with elevated pulmonary vascular resistance (PVR) in 2, atrio-ventricular canal (AVC) with elevated pulmonary vascular resistance in 1, AVC with diminutive right ventricle in 1, complex transposition of the great arteries in 3, and pulmonary atresia with complex pulmonary arteries anatomy in 1. All patients had normosystemic systolic pulmonary artery pressure. Additional procedures were performed in 7: atrial septectomy in 2, double aortic arch division in 1, patent ductus arteriosus ligation in 2, and coarctation repair in 2. There were no early or late deaths or device-related complications in a mean follow-up of 24 weeks (range, 18 to 42 weeks). A mean of 5.8 telemetric regulations per patient using the FloWatch-PAB were required to adjust the tightening of the PAB to the clinical needs (narrowing 74%, releasing 26%). At last follow-up, systolic pulmonary artery pressure was within normal range in all patients but 1. Systemic oxygen saturation demonstrated optimal regulation of the pulmonary blood flow in all according to each specific defect. Four patients were successfully corrected (VSD closure, AVSD repair, and 2 arterial switches with VSD closure). The device was easily removed and the pulmonary artery re-expanded spontaneously. CONCLUSIONS: This new device is safe and allows optimal adjustment of PAB in complex heart defects. In children requiring PAB, the use of this technology can obviate the need for early re-operations and appears to be a valuable option in the panel of surgical alternatives for selected infants.

Evaluation of a new combined SpO2/PtcCO2 sensor in anaesthetized paediatric patients.

BACKGROUND: The recently introduced TOSCA monitor (Linde Medical Sensors AG, Basel, Switzerland) combines pulse oximetry (SpO2) and transcutaneous PCO2 (PtcCO2) monitoring in a single ear sensor. The aim of the present study was to evaluate accuracy of the TOSCA monitor to estimate SaO2 and PaCO2 in anaesthetized children. METHODS: With approval of the hospital ethical committee and after obtaining informed parental consent, the TOSCA sensor was attached to one ear lobe of anaesthetized children in whom arterial access was established for cardiac catheterization or invasive blood pressure monitoring. SpO and PtcCO2 as well as SpO and PECO2 values from the anaesthesia monitoring (AS5; Datex-Ohmeda, Helsinki, Finland) were compared with SaO2 and PaCO2 values from arterial blood gas analysis. Corresponding data were compared using Bland Altman bias analysis. RESULTS: A total of 111 blood samples were taken from 60 children (median age: 4.41 years; 0.35-16.13 years). SaO2 values ranged from 63 to 100% (median: 98.7%), PaCO2 ranged from 3.8 to 7.3 kPa (median: 4.6 kPa). Mean difference (+/-2 sd) between PaCO2 and PtcCO2 was -0.035 kPa (+/-0.74 kPa), between PaCO2 and PECO2 0.002 kPa (0.73 kPa), respectively (1 kPa = 7.3 mmHg). Bias and precision between SaO2 and SpO was -0.63% (+/-2.77%) and 0.13% (+/-4.52%) between SaO2 and SpO. CONCLUSIONS: In anaesthetized children, the TOSCA ear sensor allows estimation of SaO2 and PaCO2, comparable in accuracy to endtidal capnometry and finger pulse oximetry. This makes the TOSCA monitor a helpful add-on to respiratory monitoring in anaesthetized children, in situations, in which endtidal capnometry is unreliable or difficult to establish.

Transcatheter closure of a coronary sinus defect with an Amplatzer septal occluder.

We report a successful transcatheter closure of a coronary sinus defect using an Amplatzer septal occluder in a 9.5-year-old boy suffering from a significant volume overload due to left-to-right shunt.

Transcutaneously measured near-infrared spectroscopic liver tissue oxygenation does not correlate with hepatic venous oxygenation in children.

PURPOSE: To compare transcutaneous near-infrared spectroscopic (NIRS) measured liver tissue oxygenation with hepatic vein oxygen saturation (SvhO2) in children undergoing cardiac catheterization. METHODS: A NIRS optode (containing an emitter and a receiver of near-infrared light) was placed directly below the right costal arch above the palpable liver in 40 children aged 0.02 to 7.28 yr (median: 1.8 yr). Spatially resolved spectroscopic measured tissue oxygenation index (TOI) was recorded using the NIRO-300. Paired blood samples from the hepatic vein were taken under radiological control for determination of SvhO2 in a co-oxymeter. TOI values were compared with hepatic vein oxygenation, with simultaneously obtained arterial oxygen saturation (SaO2), inferior vena cava SO2 and hemoglobin concentration using simple linear and multi-regression analysis. RESULTS: TOI values ranged from 35% to 73% (58.6 +/- 8.4%); SvhO2 from 32% to 80% (58.4 +/- 14.4%), and arterial SO2 from 54% to 100% (90.0 +/- 11.4%). TOI and hepatic vein oxygen saturation failed to correlate (r = 0.052/P = 0.752). A regression model containing arterial saturation (Delta R2 = 0.177) and the ratio of pulmonary to systemic resistance (Delta R2 = 0.095) explained 27.3% of the observed variance in TOI. In this model, hepatic vein oxygen saturation was no longer significant; explaining only 3.4% of the variance. No other variable retained a significant association. CONCLUSION: Transcutaneously measured NIRS tissue oxygenation with an optode placed over the palpable liver does not correlate with SvhO2. The value is dominated by non-hepatic variables such as arterial saturation and vascular resistances.