The right ventricular adaptations early after surgery in infants with tetralogy of Fallot are important to understand the changes that occur later on in life; this physiology has not been fully delineated. We sought to assess early postoperative right ventricular remodelling in patients with tetralogy of Fallot by cardiac MRI.

Subjects with tetralogy of Fallot under 1 year of age were recruited following complete surgical repair for tetralogy of Fallot. Protocol-based cardiac MRI to assess anatomy, function, and flows was performed before hospital discharge using the feed and sleep technique, an unsedated imaging technique.

MRI was completed in 16 subjects at a median age of 77 days (interquartile range 114). There was normal ventricular ejection fraction and indexed right ventricular end-diastolic volume (48±13 cc/m2), but elevated right ventricular mass (z score 6.2±2.4). Subjects requiring a transannular patch or right ventricle to pulmonary artery conduit had moderate pulmonary insufficiency (regurgitant fraction 27±16%).

Early right ventricular remodelling after surgical repair for tetralogy of Fallot is characterised by significant pulmonary regurgitation, right ventricular hypertrophy, and lack of dilation. Performing cardiac MRI using the feed and sleep technique is feasible in infants younger than 5 months. These results might open new avenues to study longitudinal right ventricular changes in tetralogy of Fallot and to further explore the utility of unsedated MRI in patients with other types of CHDs.

The Pediatric Heart Network designed a career development award to train the next generation of clinician scientists in paediatric-cardiology-related research, a historically underfunded area. We sought to identify the strengths/weaknesses of the programme and describe the scholars’ academic achievements and the network’s return on investment.

Survey questions designed to evaluate the programme were sent to applicants – 13 funded and 19 unfunded applicants – and 20 mentors and/or principal investigators. Response distributions were calculated. χ2 tests of association assessed differences in ratings of the application/selection processes among funded scholars, unfunded applicants, and mentors/principal investigators. Scholars reported post-funding academic achievements.

Survey response rates were 88% for applicants and 100% for mentor/principal investigators. Clarity and fairness of the review were rated as “clear/fair” or “very clear/very fair” by 98% of respondents, but the responses varied among funded scholars, unfunded applicants, and mentors/principal investigators (clarity χ2=10.85, p=0.03; fairness χ2=16.97, p=0.002). Nearly half of the unfunded applicants rated feedback as “not useful” (47%). “Expanding their collaborative network” and “increasing publication potential” were the highest-rated benefits for scholars. Mentors/principal investigators found the programme “very” valuable for the scholars (100%) and the network (75%). The 13 scholars were first/senior authors for 97 abstracts and 109 manuscripts, served on 22 Pediatric Heart Network committees, and were awarded $9,673,660 in subsequent extramural funding for a return of ~$10 for every scholar dollar spent.

Overall, patient satisfaction with the Scholar Award was high and scholars met many academic markers of success. Despite this, programme challenges were identified and improvement strategies were developed.

Cyclooxygenase inhibitors are widely applied to facilitate ductal closure in preterm infants. The mechanisms that lead to patent ductus arteriosus closure are incompletely understood. Vascular endothelial growth factor plays pivotal roles during ductal closure and remodelling.

The aim of this study was to investigate the effects of ibuprofen and indomethacin on the expression of vascular endothelial growth factor and its receptors in a primary rat ductus arteriosus endothelial cell culture.

Protein expression of vascular endothelial growth factor and vascular endothelial growth factor receptor 1 and 2 was confirmed in rat ductus arteriosus and aorta by immunofluorescence staining. Fetal rat endothelial cells were isolated from ductus arteriosus and aorta using immunomagnetic cell sorting and treated with ibuprofen or indomethacin. mRNA expression levels were assessed by quantitative polymerase chain reaction analysis.

In ductal endothelial cells, ibuprofen significantly induced vascular endothelial growth factor and its receptor 2, but not receptor 1, whereas indomethacin did not alter the expression levels of the vascular endothelial growth factor system. In contrast, ibuprofen significantly induced vascular endothelial growth factor and its receptors 1 and 2 in aortic endothelial cells, whereas indomethacin only induced vascular endothelial growth factor receptor 2.

Our results indicate differential effects of ibuprofen and indomethacin on the expression levels of the vascular endothelial growth factor system in ductus arteriosus endothelial cells. In addition, vessel-specific differences between ductal and aortic endothelial cells were found. Further in vivo studies are needed to elucidate the biological significance of these findings.

Microvascular dysfunction in hypertrophic cardiomyopathy has been associated with poor clinical outcome. Several studies have demonstrated a reduced perfusion reserve proportional to the magnitude of the hypertrophy. We investigated the utility of stress perfusion cardiac MRI to detect microvascular dysfunction in children with hypertrophic cardiomyopathy.

From January 2016 to January 2017, 13 patients, with a mean age of 15.3 years, with hypertrophic cardiomyopathy underwent regadenoson stress perfusion cardiac MRI (1.5-T Siemens Aera). A single-shot, T1-weighted saturation recovery gradient echo was used for first-pass perfusion in a multiple-slices group, including three short-axis slices and one four-chamber slice. Coronary vasodilatory stress was achieved using bolus injection of regadenoson (lexiscan 0.4 mg/5 ml) and dynamic perfusion during rest and stress performed by administering 0.05 mmol/kg of gadolinium contrast agent (gadoteridol) injected at a rate of 3.5 ml/s, followed by assessment of viability using two-dimensional phase-sensitive inversion recovery of the entire myocardium.

All patients completed protocols with no interruptions. In all, seven patients developed perfusion defects after the administration of regadenoson. Asymmetric septal hypertrophy was the most common pattern of hypertrophic cardiomyopathy (n=4) in those with abnormal perfusion. A total of four patients with perfusion defects had a maximum wall thickness <30 mm. The finding of perfusion defects in areas without late gadolinium enhancement in some of our patients indicates that gadolinium enhancement by itself could underestimate the true extension of microvascular disease. Out of seven patients, five patients with positive stress cardiac MRI have undergone implantable cardioverter defibrillator placement based on current guidelines.

Regadenoson stress cardiac MRI is feasible and clinically valuable in paediatric patients. It is particularly effective in unmasking abnormal myocardial perfusion in the presence of microvascular dysfunction in children with hypertrophic cardiomyopathy.

Children after Fontan palliation have reduced exercise capacity and quality of life. Our aim was to study whether endurance training could improve physical capacity and quality of life in Fontan patients.

Fontan patients (n=30) and healthy age- and gender-matched control subjects (n=25) performed a 6-minute walk test at submaximal capacity and a maximal cycle ergometer test. Quality of life was assessed with Pediatric Quality of Life Inventory Version 4.0 questionnaires for children and parents. All tests were repeated after a 12-week endurance training programme and after 1 year.

Patients had decreased submaximal and maximal exercise capacity (maximal oxygen uptake 35.0±5.1 ml/minute per·kg versus 43.7±8.4 ml/minute·per·kg, p<0.001) and reported a lower quality of life score (70.9±9.9 versus 85.7±8.0, p<0.001) than controls. After training, patients improved their submaximal exercise capacity in a 6-minute walk test (from 590.7±65.5 m to 611.8±70.9 m, p<0.05) and reported a higher quality of life (p<0.01), but did not improve maximal exercise capacity. At follow-up, submaximal exercise capacity had increased further and improved quality of life was sustained. The controls improved their maximal exercise capacity (p<0.05), but not submaximal exercise capacity or quality of life after training. At follow-up, improvement of maximal exercise capacity was sustained.

We believe that an individualised endurance training programme for Fontan patients improves submaximal exercise capacity and quality of life in Fontan patients and the effect on quality of life appears to be long-lasting.

Neurodevelopmental disabilities in children with CHD can result from neurologic injury sustained in the cardiac ICU when children are at high risk of acute neurologic injury. Physicians typically order and specify frequency for serial bedside nursing clinical neurologic assessments to evaluate patients’ neurologic status.

We surveyed cardiac ICU physicians to understand how these assessments are performed, and the attitudes of physicians on the utility of these assessments. The survey contained questions regarding assessment elements, assessment frequency, communication of neurologic status changes, and optimisation of assessments.

Surveys were received from 50 institutions, with a response rate of 86%. Routine clinical neurologic assessments were reported to be performed in 94% of institutions and standardised in 56%. Pupillary reflex was the most commonly reported assessment. In all, 77% of institutions used a coma scale, with Glasgow Coma Scale being most common. For patients with acute brain injury, 82% of institutions reported performing assessments hourly, whereas assessment frequency was more variable for low-risk and high-risk patients without overt brain injury. In all, 84% of respondents thought their current practice for assessing and monitoring neurologic status was suboptimal. Only 41% felt that the Glasgow Coma Scale was a valuable tool for assessing neurologic function in the cardiac ICU, and 91% felt that a standardised approach to assessing pre-illness neurologic function would be valuable.

Routine nursing neurologic assessments are conducted in most surveyed paediatric cardiac ICUs, although assessment characteristics vary greatly between institutions. Most clinicians rated current neurologic assessment practices as suboptimal.

Acute kidney injury is a frequent complication after cardiac surgery with cardiopulmonary bypass in infants. Neutrophil gelatinase-associated lipocalin has been suggested to be a promising early biomarker of impending acute kidney injury. On the other hand, neutrophil gelatinase-associated lipocalin has been shown to be elevated in systemic inflammatory diseases without renal impairment. In this secondary analysis of data from our previous study on acute kidney injury after infant cardiac surgery, our hypothesis was that neutrophil gelatinase-associated lipocalin may be associated with surgery-related inflammation.

We prospectively enrolled 59 neonates and infants undergoing cardiopulmonary bypass surgery for CHD and measured neutrophil gelatinase-associated lipocalin in plasma and urine and interleukin-6 in the plasma. Values were correlated with postoperative acute kidney injury according to the paediatric Renal-Injury-Failure-Loss-Endstage classification.

Overall, 48% (28/59) of patients developed acute kidney injury. Of these, 50% (14/28) were classified as injury and 11% (3/28) received renal replacement therapy. Both plasma and urinary neutrophil gelatinase-associated lipocalin values were not correlated with acute kidney injury occurrence. Plasma neutrophil gelatinase-associated lipocalin showed a strong correlation with interleukin-6. Urinary neutrophil gelatinase-associated lipocalin values correlated with cardiopulmonary bypass time.

Our results suggest that plasma and urinary neutrophil gelatinase-associated lipocalin values are not reliable indicators of impending acute kidney injury in neonates and infants after cardiac surgery with cardiopulmonary bypass. Inflammation may have a major impact on plasma neutrophil gelatinase-associated lipocalin values in infant cardiac surgery. Urinary neutrophil gelatinase-associated lipocalin may add little prognostic value over cardiopulmonary bypass time.

Adults with CHD often exhibit complex cardiac abnormalities, whose management requires specific clinical and surgical expertise. To enable easier access of these patients to highly specialised care, we implemented a collaborative programme that incorporates medical and surgical specialists belonging to both paediatric and adult cardiovascular institutions.

The objective of this study was to review the experience gained and to analyse the surgical outcome of major cardiac surgery.

We retrospectively reviewed all consecutive patients admitted for major cardiac surgery using our network between January, 2010 and December, 2013. Analysis of surgical outcome was performed in patients selected for major cardiac surgery with cardiopulmonary bypass. Early and late outcomes were evaluated.

Out of a total of 433 inward patients, 86 were selected for surgery. The median age was 25.5 years, –64 patients (74.4%) had previously undergone heart surgery, and –55 patients (64%) had been subjected to at least one sternotomy. Abnormalities of the left ventricular and right ventricular outflow tract were the most frequent (37.2% and 30.2%, respectively), and despite high-surgical complexity only one death occurred (in-hospital mortality 1.1%). On a median follow-up time of 4 years no deaths and no heart-failure events have occurred; one patient underwent further cardiac surgery programmed at the time of discharge.

Low mortality and morbidity rates can be obtained in high-surgical complexity adults with CHD populations when paediatric and adult cardiac specialists operate in the same multidisciplinary environment.

Although transthoracic echocardiography is the dominant imaging modality in CHD, optimal utilisation is unclear. We assessed whether adherence to the paediatric Appropriate Use Criteria for outpatient transthoracic echocardiography could reduce inappropriate use without missing significant cardiac disease.

Using the Appropriate Use Criteria, we determined the indication and appropriateness rating for each initial echocardiogram performed at our institution during calendar year 2014 (N=1383). Chart review documented ordering provider training, patient demographics, and study result, classified as normal, abnormal, or abnormal motivating treatment within a 2-year follow-up period. We tested whether provider training level or patient age correlated with echocardiographic findings or appropriateness rating.

We found that 83.9% of echocardiograms were normal and that 66.7% had an appropriate indication. Nearly all abnormal results and all results motivating treatment were in appropriate studies, giving an odds ratio of 2.73 for an abnormal result if an appropriate indication was present (95% confidence interval 1.92–3.89, p<0.001). None of the remaining initial abnormal results with less than appropriate indications became significant, resulting in treatment over 2 years. Results suggest a potential reduction in imaging volume of as much as 33% with application of the criteria. Cardiologists ordered nearly all studies resulting in treatment but also more echocardiograms with less appropriate indications. Most examinations were in older patients; however, most abnormal results were in patients younger than 1 year.

The Appropriate Use Criteria can be used to safely reduce echocardiography volume while still detecting significant heart disease.