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Background Coarctation of the aorta (CoA) is one of the most common congenital heart defects. Most patients live into adulthood as a result of improved surgical techniques; however, late complications, including hypertension, recoarctation, and arrhythmias, are common. The autonomic nervous system (ANS) might play a role in the pathology. This study evaluated cardiac ANS activity and cardiac function in children after CoA repair and investigated the relationship between the two. Methods The study participants were 31 children after CoA repair and 62 healthy controls aged between 8 and 18 years. Ambulatory impedance cardiography was used to measure cardiac ANS activity and cardiac output for 24 hours. Transthoracic echocardiography and cardiac magnetic resonance imaging were used to measure cardiac function. Results No group differences were found in ambulatory cardiac ANS activity. However, ambulatory cardiac output and left ventricular function were significantly decreased in patients compared with controls. Conclusions Left ventricular function and ambulatory cardiac output are impaired in patients after CoA repair, despite unchanged cardiac ANS activity in this group. These results underscore the importance of clinical follow-up, even in patients without residual stenosis. [ABSTRACT FROM AUTHOR]

Background: Normal values of the mathematically-synthesized vectorcardiogram (VCG) are lacking for children. Therefore, the objective of this study was to assess normal values of the pediatric synthesized VCG (spatial QRS-T angle [SA] and ventricular gradient [VG]).Methods: Electrocardiograms (ECGs) of 1263 subjects (0-24 years) with a normal heart were retrospectively selected. VCGs were synthesized by the Kors matrix. Normal values (presented as 2nd and 98th percentiles) were assessed by quantile regression with smoothing by splines.Results: Our results show that heart rate decreased over age, QRS duration increased and QTc interval remained constant. The SA initially decreased and increased again from the age of 8 years. The VG magnitude was relatively stable until the age of 2 years, after which it increased.Conclusion: Normal values of the pediatric ECG and VCG (VG and SA) were established. These normal values could be important for future studies using VG and SA for risk stratification in heart disease in children. [ABSTRACT FROM AUTHOR]

Objective: Recent descriptions of decreased exercise capacity 10 to 15 years after arterial switch operation (ASO) suggest subclinical hemodynamic restrictions. Persistent impairment of ventricular performance following ASO may add to this. We aimed to characterize the time course of changes in biventricular performance within the first year following ASO. Methods: We prospectively included 26 patients with transposition of the great arteries undergoing ASO and 20 age-matched controls. Left and right ventricular systolic and diastolic performance was assessed using tissue Doppler imaging-derived peak systolic velocity, peak diastolic velocity, and peak early wave Doppler flow velocity/early diastolic tissue Doppler imaging velocity as well as mitral and tricuspid annular plane systolic excursion. Furthermore, left ventricular longitudinal, radial, and circumferential strain were assessed using speckle tracking strain imaging. Studies were performed preoperatively, 1 day postoperatively, at discharge, and at medium-term follow-up (9 months [interquartile range, 6-23 months] postoperatively). Results: After an initial decrease in biventricular systolic and diastolic performance 1 day postoperatively versus preoperatively, recovery was observed in all parameters during medium-term follow-up. At medium-term follow-up left ventricular systolic and diastolic performance parameters were comparable in patients and controls. In contrast, right ventricular systolic and diastolic performance were still impaired in patients versus controls roughly 1 year postoperatively (tricuspid annular plane systolic excursion, 11.6 ± 2.2 vs 18.6 ± 3.1 mm; right ventricular peak systolic velocity, 8.1 ± 2.3 vs 12.6 ±1.8 cm/second; right ventricular peak diastolic velocity, 12.4 ± 3.0 vs 18.2 ± 4.2 cm/second; and right ventricular peak early wave Doppler flow velocity/early diastolic tissue Doppler imaging velocity, 6.7 ± 2.1 vs 4.3 ± 1.3; all Ps < .001). Conclusions: If early ASO is performed, left ventricular performance recovers to control values within the first postoperative year. In contrast, right ventricular systolic and diastolic performance remained impaired during follow-up, which stresses the importance of postoperative follow-up of right ventricular performance. [ABSTRACT FROM AUTHOR]

Background: Within the group of patients undergoing coarctectomy today, two subgroups can be identified: neonates with a critical coarctation and nonneonatal patients. We hypothesize that patients who have to undergo repair in the neonatal period will have more persistent impairment of ventricular performance postoperatively. Accordingly, we aimed to characterize biventricular performance after coarctectomy in neonatal and nonneonatal patients. Methods: Children (aged 0 to 17 years) undergoing a coarctectomy were prospectively included and classified as neonatal (<1 month old) or nonneonatal patients. Age-matched controls were included for each measurement occasion. To evaluate left (LV) and right ventricular (RV) performance, fractional shortening, peak systolic (S') and early diastolic (E') tissue Doppler imaging velocities, and E/E' were assessed preoperatively, at discharge, and 1 year postoperatively (11.4 ± 8.3 months). Results: In neonatal (n = 18) and nonneonatal (n = 19) patients LV performance significantly improved within the first postoperative year. Yet 1 year postoperatively, LV S' was still lower in neonatal patients vs controls (4.8 ± 1.1 vs 6.1 ± 1.6 cm/s; p = 0.036), whereas comparable results were observed in nonneonatal patients and controls. One year postoperatively, LV diastolic performance was impaired in neonatal (LV E' 8.7 ± 3.1 vs 13.2 ± 3.9 cm/s, p = 0.005) and nonneonatal patients (LV E' 12.1 ± 3.5 vs 15.1 ± 2.4 cm/s, p = 0.008) vs controls. In RV performance variables, no differences were observed 1 year postoperatively between neonatal and nonneonatal patients and controls. Conclusions: In both subgroups, LV diastolic performance does not recover to normal values within the first postoperative year. However, LV systolic performance remains more persistently impaired in patients who have to undergo repair in the neonatal period vs nonneonatal repair. [Copyright &y& Elsevier]

Background: The Brugada sign has been associated with mutations in SCN5A and with right ventricular structural abnormalities. Their role in the Brugada sign and the associated ventricular arrhythmias is unknown. Objective: The purpose of this study was to delineate the role of structural abnormalities and sodium channel dysfunction in the Brugada sign. Methods: Activation and repolarization characteristics of the explanted heart of a patient with a loss-of-function mutation in SCN5A (G752R) and dilated cardiomyopathy were determined after induction of right-sided ST-segment elevation by ajmaline. In addition, right ventricular structural discontinuities and sodium channel dysfunction were simulated in a computer model encompassing the heart and thorax. Results: In the explanted heart, disappearance of local activation in unipolar electrograms at the basal right ventricular epicardium was followed by monophasic ST-segment elevation. The local origin of this phenomenon was confirmed by coaxial electrograms. Neither early repolarization nor late activation correlated with ST-segment elevation. At sites of local ST-segment elevation, the subepicardium was interspersed with adipose tissue and contained more fibrous tissue than either the left ventricle or control hearts. In computer simulations entailing right ventricular structural discontinuities, reduction of sodium channel conductance or size of the gaps between introduced barriers resulted in subepicardial excitation failure or delayed activation by current-to-load mismatch and in the Brugada sign on the ECG. Conclusion: Right ventricular excitation failure and activation delay by current-to-load mismatch in the subepicardium can cause the Brugada sign. Therefore, current-to-load mismatch may underlie the ventricular arrhythmias in patients with the Brugada sign. [Copyright &y& Elsevier]

Fetuses with congenital heart defects (CHD) show delayed neurodevelopment, fetal growth restriction (FGR) and placenta related complications. The neurodevelopmental delay may be, partly, attributed to placental factors. As both placental development and fetal aortic flow/oxygenation influence neurodevelopment, placentas were compared within fetal CHD groups based on aortic oxygenation and flow, aiming to unravel the true effects in the developmental processes. Placental tissues of pregnancies with fetal CHD and healthy controls were selected from biobanks of two Dutch academic hospitals (LUMC, UMCU). Additionally, biometry and Dopplers were assessed. CHD cases with reduced oxygenation (RO) towards the fetal brain were compared to cases with reduced flow (RF) in the aortic arch and healthy controls. Genetic abnormalities, termination of pregnancy, fetal demise and/or multiple pregnancies were excluded. Histological outcomes were related to fetal Dopplers and biometry. A placenta severity score was used to assess the severity of placental abnormalities per case. In CHD, significantly more delayed maturation, maternal vascular malperfusion, fetal hypoxia and higher placenta severity scores (median 14 in RO, 14 in RF, 5 in controls, p < 0.001) were observed. Doppler abnormalities (PI UA > p90, PI MCA < p10, CPR < p10) and FGR were more often found in CHD. There were no differences in placental abnormalities, fetal growth and fetal Dopplers between cases with RO and RF. Fetal hemodynamics in the ascending aorta could not be related to placenta characteristics. We hypothesize that placental development influences neurodevelopment in excess of hemodynamics in CHD cases. • Placental features in fetal CHD could not be related to aortic flow and oxygenation. • Next to hemodynamic alterations, alternative contributing factors might play a role. • Abnormal placental development might influence neurodevelopment in these cases. [ABSTRACT FROM AUTHOR]

Background The policy for listing and transplant for children with dilated cardiomyopathy (DCM) in The Netherlands has been conservative because of low donor availability. The effects of this policy on outcome are reported. Methods This was a multicenter, nationwide study performed in 148 children with DCM. The primary outcome was death or heart transplant. Results Overall, 43 patients (29%) died or were transplanted. Within 1 year of diagnosis, 21 patients died, and only 4 underwent transplantation (3 on mechanical circulatory support). The 1-year survival was 85% (95% confidence interval [CI] = 79–91), and 5-year survival was 84% (95% CI = 78–90). Transplantation-free survival at 1 year was 82% (95% CI = 75–88) and at 5 years was 72% (95% CI = 64–80). Within 1 year of diagnosis, with death as the main end-point (21 of 25, 84%), intensive care unit admission (hazard ratio = 2.6, p = 0.05) and mechanical circulatory support (hazard ratio = 3.2, p = 0.03) were risk factors (multivariable Cox analysis); inotropic support was longer in patients reaching an end-point. At >1 year after diagnosis, with transplantation as the main end-point (15 of 18, 83%), age >6 years (hazard ratio = 6.1, p = 0.02) was a risk factor. There were 56 (38%) children who recovered, 50% within 1 year of diagnosis. Recovery was associated with younger age; was similar in patients with myocarditis (43%) and idiopathic disease (41%); and was similar in patients initially admitted to the intensive care unit, admitted to the ward, or treated as outpatients. Conclusions The transplantation rate in our cohort in the first year was low, with 1-year and 5-year survival rates similar to other cohorts. Our results suggest that a conservative approach to list children for transplantation early after presentation may be justifiable except for patients with prolonged intensive care unit or mechanical circulatory support. [ABSTRACT FROM AUTHOR]

Background: Specific follow-up of newly introduced echocardiographic parameters in healthy neonates and infants is limited. Aim: To prospectively describe follow-up of left ventricular (LV) tissue Doppler imaging (TDI) and speckle tracking strain parameters in healthy subjects up to two months after birth. Design: This is a longitudinal follow-up study. Subjects: Twenty-eight (10 male) healthy newborns were included and underwent transthoracic echocardiography 1–3days, 3weeks and 6–7weeks after birth. Outcome measures: In each echocardiogram, parameters describing cardiac growth, including LV mass (LVM), were assessed. Additionally, TDI derived peak systolic velocity (S′) and peak early (E′) and late (A′) diastolic velocities were assessed in the basal LV free wall and interventricular septum (IVS). Finally LV longitudinal, radial and circumferential global peak strain parameters were assessed using speckle tracking strain imaging. Results: LVM significantly increased during follow-up (7.6±2.4 versus 12.4±3.2g, p=0.002). Similarly at 1–3days versus 6–7weeks after birth, an increase in LV and IVS systolic (LV S′ 4.1±1.5 versus 6.3±1.5cm/s, p=0.001; IVS S′ 3.6±0.9 versus 6.4±1.3cm/s, p<0.001) and diastolic (LV E′ 6.1±2.2 versus 9.7±2.9cm/s, p=0.002; IVS E′ 5.1±1.4 versus 10.7±3.3cm/s, p<0.001) TDI parameters was observed. In contrast, global peak longitudinal, radial and circumferential strain parameters did not significantly change during follow-up. Conclusions: A significant increase in LV systolic and diastolic TDI parameters was observed up to two months after birth. Yet this increase may be (cardiac) growth-dependent. No significant changes were observed in speckle tracking strain derived global peak strain parameters; this may render the technique particularly valuable in evaluation of LV systolic performance during periods of significant growth, such as the neonatal period. [ABSTRACT FROM AUTHOR]

Little is known about the effects of “second-generation drugs” (prostanoids, endothelin receptor antagonists, 5-phosphodiesterase inhibitors) in children with pulmonary arterial hypertension (PAH). This study describes the outcome of a national cohort of children with PAH in an era when these drugs became available. From 1993 to 2008, 52 consecutive children with idiopathic PAH (n = 29) or systemic-to-pulmonary shunt-associated PAH (n = 23) underwent baseline and follow-up assessments. Treatment was initiated depending on functional class, acute pulmonary vasoreactivity response, and drug availability. Observed survival was evaluated depending on time of diagnosis in relation to second-generation drug availability and subsequently compared to calculated predicted survival. Children for whom second-generation drugs were available had improved survival compared to their predicted survival (1-, 3-, and 5-year survival rates 93%, 83%, and 66% vs 79%, 61%, and 50%, respectively). However, this improved survival was observed only in patients for whom second-generation drugs became available during their disease course. No improved survival was observed in patients for whom drugs were available already at diagnosis. Baseline variables associated with decreased survival included higher functional class, higher pulmonary-to-systemic arterial pressure ratio, lower cardiac index, and higher serum levels of N-terminal pro–brain natriuretic peptide and uric acid. After start of second-generation drugs, functional class, 6-minute walking distance, and N-terminal pro–brain natriuretic peptide improved but gradually decreased after longer follow-up. In conclusion, survival of pediatric PAH seemed improved since the introduction of second-generation drugs only in selected patients for whom these drugs became available during their disease course. Start of second-generation drugs initially induced clinical improvements, but these effects decreased after longer follow-up. [Copyright &y& Elsevier]