Pulmonary arterial hypertension in children after neonatal arterial switch operation.

OBJECTIVES: Paediatric pulmonary arterial hypertension (PAH) after neonatal arterial switch operation (ASO) for transposition of the great arteries (TGA) is a clinically recognised entity with an estimated incidence of 0.6%-1.0%. Nevertheless, a clinical characterisation is lacking. We present an international cohort of children with PAH after neonatal ASO for TGA and describe epidemiology and clinical course. METHODS: Data were collected of children with PAH after neonatal ASO (≤6 weeks after birth) for simple TGA without residual shunt defects, identified in four national paediatric PAH networks in Europe and one US referral centre. RESULTS: Twenty-five children were identified between 1989 and 2014. In 17 children (68%), PAH was detected <1 year after ASO. In the remaining children, PAH was detected after median 64 months (IQR 19.5, 94.5). Nineteen children (96%) received PAH-targeted therapies. During follow-up after ASO (median 5.2 years), eight children died, four underwent lung transplantation and two received a Potts shunt. 1-year and 5-year Potts shunt- and transplantation-free survival after ASO was 100% and 73%. From first PAH detection, this was 100% and 58%, respectively, which did not differ between children with early (<1 year after ASO) or late PAH detection. CONCLUSIONS: The occurrence of PAH after ASO for TGA represents a specific association. PAH onset may be early or late after ASO, with similar fatal course from first PAH detection. Mechanisms leading to PAH in this association are unknown, but may include abnormal prenatal pulmonary haemodynamics and/or genetic susceptibility. Routine, lifelong follow-up for children who undergo ASO for TGA should include screening for PAH.

N-Terminal proBNP Levels and Tissue Doppler Echocardiography in Acute Rheumatic Carditis.

Background. Rheumatic heart disease (RHD) is a leading cause of heart failure in children and young adults worldwide. B-type natriuretic peptide (BNP) is a useful marker of critical pediatric heart disease, and its N-terminal peptide, NT-proBNP, is elevated in congenital and acquired heart disease in children. Aim. To measure NT-proBNP levels as a marker of carditis in children with acute rheumatic carditis, as compared to children with quiescent RHD and healthy controls. Methods. 16 children with acute rheumatic carditis, 33 children with quiescent RHD, and a cohort of 30 healthy children were studied. Transthoracic echocardiography was performed to assess valve and cardiac function. Tissue Doppler echocardiography was performed for E/E' (ratio between mitral inflow E wave and lateral mitral annulus E' wave) and systolic strain. Results. NT-proBNP levels were significantly higher in children with acute rheumatic carditis and dropped with its resolution. Strain and E/E' values were comparable among the three groups. Conclusion. NT-proBNP is significantly elevated in children with acute rheumatic carditis in the acute stage compared to children with quiescent RHD and healthy subjects, in the presence of comparable echocardiographic indices of LV systolic and diastolic function.

Proximal aortic stiffness is increased in systemic lupus erythematosus activity in children and adolescents.

Patients with systemic lupus erythematosus (SLE) are prone to premature atherosclerosis and are at risk for the development of cardiovascular disease. Increased arterial stiffness is emerging as a marker of subclinical atherosclerosis. Purpose. To measure proximal aortic stiffness in children and adolescents with SLE. Methods. We studied 16 patients with SLE in activity (mean age 15 ± 2.42 years; 16 females), 14 patients with SLE not in activity (mean age 15.7 ± 1.89 years; 4 males, 10 females), and 16 age- and sex-comparable healthy children and adolescents (15.5 ± 1.71 years; 4 males, 12 females). Disease activity was determined by the SLE disease activity index (SLEDAI). All subjects underwent echocardiography for assessment of proximal aortic pulse wave velocity (PWV) [Ao distance/Ao wave transit time in the aortic arch]. Venous blood samples were collected for ESR. Results. Patients in activity had significantly higher PWV values than controls (P < 0.05), while no significant difference was found between patients not in activity and controls. Conclusions. SLE patients with disease activity demonstrate increased PWV and arterial stiffness of the proximal aorta, while patients without disease activity do not. This suggests that inflammation secondary to SLE activity, and not subclinical atherosclerosis, is the major underlying cause for increased arterial stiffness in this age group.

Pediatric cardiomyopathies over the last decade: a retrospective observational epidemiology study in a tertiary institute, Egypt.

BACKGROUND: Pediatric cardiomyopathy (CM) is a rare, life-threatening disorder of unknown etiology. Data on CM in Egypt are scarce as there is no national registry. This study was an effort to understand the demographic features, clinical presentation, and frequency of different types of childhood CM in Egypt. MATERIALS AND METHODS: Medical files of all children diagnosed with CM in the last decade (1997-2007) and referred to the Pediatric Cardiology Clinic at Ain Shams University, Children's Hospital (Cairo, Egypt), were reviewed. This study included 124 (6.6%) cardiomyopathic patient files from a total of 1876 cardiac patients that were followed up at the Pediatric Cardiology Clinic during the 10-year study period. RESULTS: In the last decade (1997-2007), children with CM represented 6.6% of all children with cardiovascular diseases followed at the Pediatric Cardiology Clinic; 73 were boys (58.9%) and 51 were girls (41.1%), with a mean age of 3.82±3.99 years. Parental consanguinity was positive in 19.4% of patients and a history of preceding viral infection was present in one patient (0.8%). Eight patients had a similarly affected sibling (6.5%). CONCLUSION AND RECOMMENDATIONS: Data on CM in Egypt are scarce, highlighting the urgent need for a national registry for CM (a) to allow more accurate assessment of the size of this problem, especially in children; (b) to minimize loss of follow-up data when patients move from one region to another; and (c) to allow screening of family members of a proband case.

Radionuclide ventriculography detects early anthracycline cardiotoxicity in children with Hodgkin lymphoma.

Serial echocardiography to detect doxorubicin dose-related cardiotoxicity correlates poorly with endomyocardial biopsy-proven cardiotoxicity. To compare radionuclide ventriculography (RVG) and echocardiography for the assessment of left ventricular (LV) function in children with Hodgkin disease (HD) receiving doxorubicin, we studied 39 children with HD before radiotherapy, both early (≤ 2 adriamycin, bleomycin, vinblastine, and dacarbazine cycles) (group A; n=10) and late (≥ 6 adriamycin, bleomycin, vinblastine, and dacarbazine cycles) (group B; n=36) during treatment. Seven children were assessed twice. The patients underwent full clinical assessment, echocardiography, and RVG. In group A, LV ejection fraction (LVEF) was significantly lower when measured by RVG compared with echocardiography (P<0.05). Group B had lower LVEF compared with group A by echocardiography (P=0.09), and by RVG (P=0.000). Paired analysis of children studied early and late showed a significant drop in LVEF by echocardiography (58.7 ± 7.3 vs. 52 ± 52.44%; P=0.04) and RVG (51.4 ± 2.6% vs. 47.2 ± 3.1%; P=0.004). The cumulative dose of doxorubicin inversely correlated with RVG-measured LVEF (r=-0.531; P=0.001). No correlation was found between LVEF measured by RVG and echocardiography (r=0.217; P=0.25). Cardiotoxicity occurred early and at low cumulative doses of doxorubicin in children with HD. RVG was more sensitive than echocardiography in detecting early impairment of LV function. We recommend baseline and serial assessment of LV function by RVG in children with HD receiving doxorubicin.

Patent arterial duct.

Patent arterial duct (PAD) is a congenital heart abnormality defined as persistent patency in term infants older than three months. Isolated PAD is found in around 1 in 2000 full term infants. A higher prevalence is found in preterm infants, especially those with low birth weight. The female to male ratio is 2:1. Most patients are asymptomatic when the duct is small. With a moderate-to-large duct, a characteristic continuous heart murmur (loudest in the left upper chest or infraclavicular area) is typical. The precordium may be hyperactive and peripheral pulses are bounding with a wide pulse pressure. Tachycardia, exertional dyspnoea, laboured breathing, fatigue or poor growth are common. Large shunts may lead to failure to thrive, recurrent infection of the upper respiratory tract and congestive heart failure. In the majority of cases of PAD there is no identifiable cause. Persistence of the duct is associated with chromosomal aberrations, asphyxia at birth, birth at high altitude and congenital rubella. Occasional cases are associated with specific genetic defects (trisomy 21 and 18, and the Rubinstein-Taybi and CHARGE syndromes). Familial occurrence of PAD is uncommon and the usual mechanism of inheritance is considered to be polygenic with a recurrence risk of 3%. Rare families with isolated PAD have been described in which the mode of inheritance appears to be dominant or recessive. Familial incidence of PAD has also been linked to Char syndrome, familial thoracic aortic aneurysm/dissection associated with patent arterial duct, and familial patent arterial duct and bicuspid aortic valve associated with hand abnormalities. Diagnosis is based on clinical examination and confirmed with transthoracic echocardiography. Assessment of ductal blood flow can be made using colour flow mapping and pulsed wave Doppler. Antenatal diagnosis is not possible, as PAD is a normal structure during antenatal life. Conditions with signs and symptoms of pulmonary overcirculation secondary to a left-to-right shunt must be excluded. Coronary, systemic and pulmonary arteriovenous fistula, peripheral pulmonary stenosis and ventricular septal defect with aortic regurgitation and collateral vessels must be differentiated from PAD on echocardiogram. In preterm infants with symptomatic heart failure secondary to PAD, treatment may be achieved by surgical ligation or with medical therapy blocking prostaglandin synthesis (indomethacin or ibuprofen). Transcatheter closure of the duct is usually indicated in older children. PAD in preterm and low birth weight infants is associated with significant co-morbidity and mortality due to haemodynamic instability. Asymptomatic patients with a small duct have a normal vital prognosis but have a lifetime risk of endocarditis. Patients with moderate-to-large ducts with significant haemodynamic alterations may develop irreversible changes to pulmonary vascularity and pulmonary hypertension.