The Utility of CT Angiography in Neonates with Pulmonary Atresia with Intact Ventricular Septum and Concern for Right Ventricular Dependent Coronary Circulation: Case Series.

Up to one third of patients with pulmonary atresia with intact ventricular septum (PA-IVS) will have inadequate anterograde coronary blood flow and rely on fistulous connections from the right ventricle (RV) for myocardial perfusion, known as RV-dependent coronary circulation (RVDCC). Historically, identification of the extent of ventriculocoronary connections and coronary stenosis has required invasive imaging with cardiac catheterization and angiography. Cardiac computed tomography (CCT) potentially provides a less invasive imaging option for therapeutic planning in this group of patients. We describe six neonates with PA-IVS who underwent both CCT and cardiac catheterization at our institution prior to any surgical or transcatheter intervention between 2009 and 2019. Imaging was concerning for RVDCC in all six patients. The average tricuspid Z-score was - 4.19 (2.1 to - 5.34). Two patients underwent cardiac transplantation and two patients underwent ductal stenting. The overall mortality rate was 50%. CCT findings closely mirrored the findings of invasive cardiac catheterization and identified important morphological variations. The average radiation exposure (DLP) per CCT was (10.5 mGy cm, range 6-20). Technological improvements in CCT have enabled adequate visualization of coronary anomalies in children with comparable accuracy to cardiac catheterization, but considerably less radiation exposure. However, diagnosis of RVDCC requires direct right ventricular angiography. Therefore, the potential benefit of obtaining a CCT prior to catheterization for infants with PA-IVS is the ability to risk stratify, assist with procedural planning, and improve family counseling.

Cardiac Magnetic Resonance Imaging to Determine Single Ventricle Function in a Pediatric Population is Feasible in a Large Trial Setting: Experience from the Single Ventricle Reconstruction Trial Longitudinal Follow up.

The Single Ventricle Reconstruction (SVR) Trial was a randomized prospective trial designed to determine survival advantage of the modified Blalock-Taussig-Thomas shunt (BTTS) vs the right ventricle to pulmonary artery conduit (RVPAS) for patients with hypoplastic left heart syndrome. The primary aim of the long-term follow-up (SVRIII) was to determine the impact of shunt type on RV function. In this work, we describe the use of CMR in a large cohort follow up from the SVR Trial as a focused study of single ventricle function. The SVRIII protocol included short axis steady-state free precession imaging to assess single ventricle systolic function and flow quantification. There were 313 eligible SVRIII participants and 237 enrolled, ages ranging from 10 to 12.5 years. 177/237 (75%) participants underwent CMR. The most common reasons for not undergoing CMR exam were requirement for anesthesia (n = 14) or ICD/pacemaker (n = 11). A total of 168/177 (94%) CMR studies were diagnostic for RVEF. Median exam time was 54 [IQR 40-74] minutes, cine function exam time 20 [IQR 14-27] minutes, and flow quantification time 18 [IQR 12-25] minutes. There were 69/177 (39%) studies noted to have intra-thoracic artifacts, most common being susceptibility artifact from intra-thoracic metal. Not all artifacts resulted in non-diagnostic exams. These data describe the use and limitations of CMR for the assessment of cardiac function in a prospective trial setting in a grade-school-aged pediatric population with congenital heart disease. Many of the limitations are expected to decrease with the continued advancement of CMR technology.

Patent Ductus Arteriosus Response to Treatment by Course and Associations with Perinatal and Clinical Factors.

OBJECTIVE: The objective of this study is to examine patent ductus arteriosus (PDA) response by treatment course and investigate associations with postmenstrual age (PMA), chronological age (CA), gestational age (GA), antenatal steroid exposure (ANS), birthweight (BW), weight at treatment initiation (WT), and PDA/left pulmonary artery (LPA) ratio. STUDY DESIGN: This is a single-center retrospective cohort study of preterm infants less than 37 weeks' GA born January 1, 2016 to December 31, 2018 who received acetaminophen and/or indomethacin for PDA treatment. Cox proportional hazards regression models were used to determine whether factors of interest were associated with PDA response to medical treatment. RESULTS: In total, 289 treatment courses were administered to 132 infants. Thirty-one (23%) infants experienced treatment-associated PDA closure. Ninety-four (71%) infants had evidence of PDA constriction following any treatment course. Ultimately, 84 (64%) infants experienced definitive PDA closure. For each 7-day increase in CA at the time of treatment initiation, the PDA was 59% less likely to close (p = 0.04) and 42% less likely to respond (i.e., constrict or close) to treatment (p < 0.01). PDA/LPA ratio was associated with treatment-associated PDA closure (p = 0.01). For every 0.1 increase in the PDA/LPA ratio, the PDA was 19% less likely to close in response to treatment. CONCLUSION: In this cohort, PDA closure is independent of PMA, GA, ANS, BW, and WT; however, CA at treatment initiation predicted both treatment-associated PDA closure and PDA response (i.e., constriction or closure), and PDA/LPA ratio was associated with treatment-associated closure. Most infants experienced PDA constriction rather than closure, despite receiving up to four treatment courses. KEY POINTS: · Detailed PDA responses for up to four treatment courses provide a novel perspective.. · Chronological age at the start of treatment predicted treatment-associated PDA closure and response.. · For each 7-day increase in chronological age, the PDA was 59% less likely to close..

High Acuity Therapy Variation Across Pediatric Acute Care Cardiology Units: Results from the Pediatric Acute Care Cardiology Collaborative Hospital Surveys.

We utilized the multicenter Pediatric Acute Care Cardiology Collaborative (PAC3) 2017 and 2019 surveys to describe practice variation in therapy availability and changes over a 2-year period. A high acuity therapies (ATs) score was derived (1 point per positive response) from 44 survey questions and scores were compared to center surgical volume. Of 31 centers that completed the 2017 survey, 26 also completed the 2019 survey. Scores ranged from 11 to 34 in 2017 and 11 to 35 in 2019. AT scores in 2019 were not statistically different from 2017 scores (29/44, IQR 27-32.5 vs. 29.5/44, IQR 27-31, p = 0.9). In 2019, more centers reported initiation of continuous positive airway pressure (CPAP) and Bi-level positive airway pressure (BiPAP) in Acute Care Cardiology Unit (ACCU) (19/26 vs. 4/26, p < 0.001) and permitting continuous CPAP/BiPAP (22/26 vs. 14/26, p = 0.034) compared to 2017. Scores in both survey years were significantly higher in the highest surgical volume group compared to the lowest, 33 ± 1.5 versus 25 ± 8.5, p = 0.046 and 32 ± 1.7 versus 23 ± 5.5, p = 0.009, respectively. Variation in therapy within the ACCUs participating in PAC3 presents an opportunity for shared learning across the collaborative. Experience with PAC3 was associated with increasing available respiratory therapies from 2017 to 2019. Whether AT scores impact the quality and outcomes of pediatric acute cardiac care will be the subject of further investigation using a comprehensive registry launched in early 2019.

Improved outcomes after implementation of a specialized pediatric cardiac rapid response team.

INTRODUCTION: The efficacy of a specialized pediatric cardiac rapid response team is unknown. We hypothesized that a specialized cardiac rapid response team would facilitate team-wide communication between the cardiac stepdown unit and cardiac intensive care unit (ICU) teams and improve patient care. MATERIALS AND METHODS: A specialized pediatric cardiac rapid response team was implemented in June 2015. All pediatric cardiac rapid response team activations and outcomes from implementation through December 2018 were reviewed. Cardiac arrests and unplanned transfers to the cardiac ICU were indexed to 1000 patient-days to account for inpatient volume trends and evaluated over time. RESULTS: There were 202 cardiac rapid response team activations in 108 unique patients during the study period. After implementation of the pediatric cardiac rapid response team, unplanned transfers from the cardiac stepdown unit to the cardiac ICU decreased from 16.8 to 7.1 transfers per 1000 patient days (p = 0.012). The stepdown unit cardiac arrest rate decreased from 1.2 to 0.0 arrests per 1000 patient-days (p = 0.015). There was one death on the cardiac stepdown unit in the 5 years since the implementation of the cardiac rapid response team, compared to four deaths in the previous 5 years. CONCLUSIONS: A reduction in unplanned cardiac ICU transfers, cardiac arrests, and mortality on the cardiac stepdown unit has been observed since the implementation of a specialized pediatric cardiac rapid response team. A specialized cardiac rapid response team may improve communication and empower the interdisciplinary care team to escalate care for patients experiencing clinical decline.

Coronary artery assessment using self-navigated free-breathing radial whole-heart magnetic resonance angiography in patients with congenital heart disease.

OBJECTIVES: To evaluate a self-navigated free-breathing three-dimensional (SNFB3D) radial whole-heart MRA technique for assessment of main coronary arteries (CAs) and side branches in patients with congenital heart disease (CHD). METHODS: SNFB3D-MRA datasets of 109 patients (20.1±11.8 years) were included. Three readers assessed the depiction of CA segments, diagnostic confidence in determining CA dominance, overall image quality and the ability to freeze cardiac and respiratory motion. Vessel sharpness was quantitatively measured. RESULTS: The percentages of cases with excellent CA depiction were as follows (mean score): left main, 92.6 % (1.92); left anterior descending (LAD), 88.3 % (1.88); right (RCA), 87.8 % (1.85); left circumflex, 82.8 % (1.82); posterior descending, 50.2 % (1.50) and first diagonal, 39.8 % (1.39). High diagnostic confidence for the assessment of CA dominance was achieved in 56.2 % of MRA examinations (mean score, 1.56). Cardiac motion freezing (mean score, 2.18; Pearson's r=0.73, P<0.029) affected image quality more than respiratory motion freezing (mean score, 2.20; r=0.58, P<0.029). Mean quantitative vessel sharpness of the internal thoracic artery, RCA and LAD were 53.1, 52.5 and 48.7 %, respectively. CONCLUSIONS: Most SNFB3D-MRA examinations allow for excellent depiction of the main CAs in young CHD patients; visualisation of side branches remains limited. KEY POINTS: • Self-navigated free-breathing three-dimensional magnetic resonance angiography (SNFB3D-MRA) sufficiently visualises coronary arteries (CAs). • Depiction of main CAs in patients with congenital heart disease is excellent. • Visualisation of CA side branches using SNFB3D-MRA is limited. • SNFB3D-MRA image quality is especially correlated to cardiac motion freezing ability.

How should we diagnose and differentiate hearts with double-outlet right ventricle?

Many, if not most, of the controversies regarding the description of the congenitally malformed heart have been resolved over the turn of the 20th century. A group of lesions that remains contentious is the situation in which both arterial trunks, in their greater part, are supported by the morphologically right ventricle. It was considered, for many years, that presence of bilateral infundibulums, or conuses, was a necessity for such a diagnosis. It has now been appreciated that this suggestion founders on many counts. In the first instance, such bilateral infundibulums are to be found in patients with other ventriculo-arterial connections, including the otherwise normal heart. In the second instance, it is clear that such an approach abrogates the important principle now known as the morphological method. This states that entities should be defined in terms of their intrinsic morphology and not on the basis of other variable features. It is now also clear that, when assessed simply on the basis of the ventricular origin of the arterial trunks, a significant number of patients fulfil the criteria for so-called "200%" origin of the trunks from the right ventricle when there is fibrous continuity between the leaflets of the atrioventricular and arterial valves. In this review, we show how attention to the morphology of the channel between the ventricles now provides the key to accurately diagnose the ventriculo-arterial connection in patients with suspected double-outlet right ventricle. This is because, when both arterial trunks arise exclusively or predominantly from the morphologically right ventricle, the outlet septum, of necessity, is itself a right ventricular structure. The channel between the ventricles, therefore, is roofed by the inner heart curvature, whether that structure is fibrous or muscular. Our observations then confirm that it is the attachment of the outlet septum, which itself can be muscular or fibrous, which determines the commitment of the interventricular communication to the subarterial outlets. The interventricular communication itself, when directly committed to the ventricular outlets, opens between the limbs of the septomarginal trabeculation or septal band. The defect is subaortic when the outlet septum is attached to the cranial limb of the trabeculation, subpulmonary when attached to the caudal limb, and doubly committed when attached to the inner heart curvature in the roof of the defect. Non-committed defects are no longer positioned within the limbs of the septomarginal trabeculation. Although readily demonstrable by a skilled echocardiographer, we show how these anatomical features are more easily demonstrated with added accuracy when using CT data sets.

Fetal and Neonatal Effects of N-Acetylcysteine When Used for Neuroprotection in Maternal Chorioamnionitis.

OBJECTIVE: To evaluate the clinical safety of antenatal and postnatal N-acetylcysteine (NAC) as a neuroprotective agent in maternal chorioamnionitis in a randomized, controlled, double-blinded trial. STUDY DESIGN: Twenty-two mothers >24 weeks gestation presenting within 4 hours of diagnosis of clinical chorioamnionitis were randomized with their 24 infants to NAC or saline treatment. Antenatal NAC (100 mg/kg/dose) or saline was given intravenously every 6 hours until delivery. Postnatally, NAC (12.5-25 mg/kg/dose, n = 12) or saline (n = 12) was given every 12 hours for 5 doses. Doppler studies of fetal umbilical and fetal and infant cerebral blood flow, cranial ultrasounds, echocardiograms, cerebral oxygenation, electroencephalograms, and serum cytokines were evaluated before and after treatment, and 12, 24, and 48 hours after birth. Magnetic resonance spectroscopy and diffusion imaging were performed at term age equivalent. Development was followed for cerebral palsy or autism to 4 years of age. RESULTS: Cardiovascular measures, cerebral blood flow velocity and vascular resistance, and cerebral oxygenation did not differ between treatment groups. Cerebrovascular coupling was disrupted in infants with chorioamnionitis treated with saline but preserved in infants treated with NAC, suggesting improved vascular regulation in the presence of neuroinflammation. Infants treated with NAC had higher serum anti-inflammatory interleukin-1 receptor antagonist and lower proinflammatory vascular endothelial growth factor over time vs controls. No adverse events related to NAC administration were noted. CONCLUSIONS: In this cohort of newborns exposed to chorioamnionitis, antenatal and postnatal NAC was safe, preserved cerebrovascular regulation, and increased an anti-inflammatory neuroprotective protein. TRIAL REGISTRATION: ClinicalTrials.gov: NCT00724594.

ECG-synchronized CT angiography in 324 consecutive pediatric patients: spectrum of indications and trends in radiation dose.

The aim of the study is to describe the spectrum of indications for pediatric ECG-synchronized CT angiography (CTA), the main determinants of radiation exposure, and trends in radiation dose over time at a single, tertiary referral center. The study was IRB approved and HIPAA compliant with informed consent waived. Between 2005 and 2013, 324 pediatric patients underwent ECG-synchronized CTA to evaluate known or suspected cardiovascular abnormalities (109 female, median age 8.1 years). The effective dose (ED) was calculated using age-specific correction factors. Univariate and multivariate regression analyses were performed to identify predictors of radiation dose. The most common primary indications for the CTA examinations included known or suspected coronary pathologies (n = 166), complex congenital heart disease (n = 73), and aortic pathologies (n = 41). Median radiation exposure decreased from 12 mSv for patients examined in the years 2005-2007 to 1.2 mSv for patients examined in the years 2011-2013 (p < 0.001). Patients scanned using a tube potential of 80 kV (n = 259) had a significantly lower median radiation dose (1.4 mSv) compared to patients who were scanned at 100 kV (n = 46, median 6.3 mSv) or 120 kV (n = 19, median 19 mSv, p < 0.001). Tube voltage, followed by tube current and the method of ECG-synchronization were the strongest independent predictors of radiation dose. Growing experience with dose-saving techniques and CTA protocols tailored to the pediatric population have led to a tenfold reduction in radiation dose over recent years and now allow routinely performing ECG-synchronized CTA in children with a radiation dose on the order of 1 mSv.

Isomerism or heterotaxy: which term leads to better understanding?

Use of correct nomenclature is important in all aspects of medicine. Many of the controversies that have bedeviled paediatric cardiology have devolved from the inappropriate use of words to describe the lesions to be found when the heart is congenitally abnormal. A continuing area of disagreement is the situation currently described by many as representing "heterotaxy". When used literally, this word means any departure from the normal. Thus, all congenitally malformed hearts represent examples of heterotaxy. By convention, nonetheless, the term is used to describe the arrangement in which the bodily organs, including parts of the heart, are not in their usual or in their mirror-imaged patterns. The arrangements, therefore, represent the presence of the organs on the right and left sides of the body being mirror imaged, in other words isomeric; however, not all the organs are uniformly isomeric. In this review, we show that, when assessed on the basis of the morphology of the atrial appendages, specifically the extent of the pectinate muscles relative to the atrioventricular junctions, isomerism is an unequivocal finding within the heart. Only the atrial appendages, however, are truly isomeric. The potential problem of disharmony between the various systems of organs is resolved simply by accounting specifically for each of the systems. On these bases, we suggest that the isomeric arrangements can now readily be diagnosed in the clinical setting, and differentiated into their right and left isomeric variants. We propose that such distinctions will provide the key for establishing the genetic cues responsible for the formation of the isomeric as opposed to the lateralised arrangements.

What is aortic overriding?

BACKGROUND: Disagreement currently exists regarding the definition of aortic dextroposition. It is suggested that the term be used interchangeably with aortic overriding, along with suggestions that the aortic valve overrides in the normal heart. The dextroposed aorta, however, does not always override the crest of the muscular ventricular septum. It is incorrect to argue that the normal aortic valve overrides. It is the cavity of the right aortic valvar sinus, rather than the valvar orifice, that sits above the muscular septum when the septum itself is intact. Therefore, to circumvent these difficulties, those using the term "dextroposition" find it necessary to distinguish "true" as opposed to "false" categories. The problems arise because "dextroposition" is remarkably ill-suited as an alternative term for aortic valvar overriding. METHODS AND RESULTS: In this review, combining developmental, morphologic, and clinical data, we show how aortic overriding is best considered on the basis of biventricular connection of the aortic root in the setting of deficient ventricular septation. When analysed in this manner, it becomes an easy matter to distinguish between one-to-one and double outlet ventriculo-arterial connections. Appreciation of these features emphasises the different spatial alignments of interventricular communications as opposed to the plane of deficient ventricular septation. The concept of overriding is applicable not only to biventricular connection of the aortic root, but also the pulmonary and common arterial roots. CONCLUSIONS: The diagnostic techniques now available to the paediatric cardiologist illustrate the features of arterial valvar overriding with exquisite accuracy, informing the discussions now required for optimal decision making.

Imaging in congenital pulmonary vein anomalies: the role of computed tomography.

Pulmonary venous anomalies comprise a wide spectrum of anatomical variations and their clinical presentations may vary from the relatively benign single partial anomalous pulmonary venous connection (PAPVC) to the critical obstructed total anomalous pulmonary venous connection (TAPVC). We briefly review the common anomalies encountered, while highlighting the utility that computed tomographic angiography (CTA) provides for this spectrum of extracardiac vascular malformations and connections. CTA has established itself as an invaluable imaging modality in these patients. A detailed knowledge of the CTA imaging findings in pulmonary venous anomalies is crucial to guide clinical decision-making in these patients.

Left ventricular pseudoaneurysm after perventricular ventricular septal defect device closure.

Perventricular ventricular septal defect (VSD) closure has been adopted as a therapeutic option for selected patients with muscular VSDs. This technique may combine some of the advantages of surgical and interventional techniques. Complication rates have been low: only one case of procedure-related left ventricular (LV) pseudoaneurysm has been documented. We report the surgical repair for a LV pseudoaneurysm after perventricular VSD device closure.

Comparison of pressure-volume loop and echocardiographic measures of diastolic function in patients with a single-ventricle physiology.

Echocardiographic measurements of diastolic function have not been validated against invasive pressure-volume loop (PVL) analysis in the single-ventricle population. The authors hypothesized that echocardiographic measures of diastolic function would correlate with PVL indices of diastolic function in patients with a single-ventricle physiology. The conductance-derived PVL measures of diastolic function included the isovolumic relaxation time constant (τ), the maximum rate of ventricular pressure decline (peak -dP/dt), and a measure of passive diastolic stiffness (µ). The echocardiographic measures included Doppler inflow patterns of the dominant atrioventricular valve (DAVV), tissue Doppler velocities (TDI) at the lateral (ventricular free wall) component of the DAVV annulus, and the TDI-derived isovolumic relaxation time (IVRT'). The correlation between PVL and echocardiographic measures was examined. The study enrolled 13 patients at various stages of surgical palliation. The median age of the patients was 3 years (range 3 months to 19 years). τ correlated well with Doppler E:A (r = 0.832; p = 0.005), lateral E:E' (r = 0.747; p = 0.033), and IVRT' (r = 0.831; p = 0.001). Peak -dP/dt also was correlated with IVRT' (r = 0.609; p = 0.036), and µ also was correlated with IVRT' (r = 0.884; p = 0.001). This study represents the first-ever comparison of diastolic echocardiographic and PVL indices in a single-ventricle population. The findings show that Doppler E:A, lateral E:E', and IVRT' correlate well with PVL measures of diastolic function. This study supports further validation of echocardiographic measures of diastolic function versus PVL measures of diastolic function in the single-ventricle population.

Cardiovascular CT angiography in neonates and children: image quality and potential for radiation dose reduction with iterative image reconstruction techniques.

OBJECTIVES: To evaluate image quality (IQ) of low-radiation-dose paediatric cardiovascular CT angiography (CTA), comparing iterative reconstruction in image space (IRIS) and sinogram-affirmed iterative reconstruction (SAFIRE) with filtered back-projection (FBP) and estimate the potential for further dose reductions. METHODS: Forty neonates and children underwent low radiation CTA with or without ECG synchronisation. Data were reconstructed with FBP, IRIS and SAFIRE. For ECG-synchronised studies, half-dose image acquisitions were simulated. Signal noise was measured and IQ graded. Effective dose (ED) was estimated. RESULTS: Mean absolute and relative image noise with IRIS and full-dose SAFIRE was lower than with FBP (P < 0.001), while SNR and CNR were higher (P < 0.001). Image noise was also lower and SNR and CNR higher in half-dose SAFIRE studies compared with full-and half-dose FBP studies (P < 0.001). IQ scores were higher for IRIS, full-dose SAFIRE and half-dose SAFIRE than for full-dose FBP and higher for half-dose SAFIRE than for half-dose FBP (P < 0.05). Median weight-specific ED was 0.3 mSv without and 1.36 mSv with ECG synchronisation. The estimated ED of half-dose SAFIRE studies was 0.68 mSv. CONCLUSIONS: IR improves image noise, SNR, CNR and subjective IQ compared with FBP in low-radiation-dose paediatric CTA and allows further dose reductions without compromising diagnostic IQ. KEY POINTS: • Iterative reconstruction techniques significantly improve non-invasive cardiovascular CT in children. • Using half traditional radiation dose image quality is higher with iterative reconstruction. • Iterative reconstruction techniques may allow further radiation reductions in paediatric cardiovascular CT.

Effective radiation dose in computed tomographic angiography of the chest and diagnostic cardiac catheterization in pediatric patients.

Computed tomographic angiography (CTA) and cardiac catheterization are useful adjuncts to echocardiography for delineating cardiovascular anatomy in pediatric patients. These studies require ionizing radiation, and it is paramount to understand the amount of radiation pediatric patients receive when these tests are performed. Modern dosimetry methods facilitate the conversion of radiation doses of varying units into an effective radiation dose. To compare the effective radiation dose between nongated CTA of the chest and diagnostic cardiac catheterization in pediatric patients. This is a retrospective cohort study of patients of patients who underwent either nongated CTA of the chest or diagnostic cardiac catheterization between July 2009 and April 2010. Fifty patients were included in each group as consecutive samples at a single tertiary care center. An effective radiation dose (mSv) was formulated using conversion factors for each group. The median effective dose (ED) for the CTA group was 0.74 mSv compared with 10.8 mSv for the catheterization group (p < 0.0001). The median ED for children <1 year of age in the CTA group was 0.76 mSv compared with 13.4 mSv for the catheterization group (p < 0.0001). Nongated CTA of the chest exposes children to 15 times less radiation than diagnostic cardiac catheterization. Unless hemodynamic data are necessary, CTA of the chest should be considered in lieu of diagnostic cardiac catheterization in patients with known or presumed cardiac disease who need additional imaging beyond echocardiography.

Preoperative Computed Tomographic Angiography Can Predict Need for Branch Pulmonary Artery Intervention in Patients With Ductal-Dependent Pulmonary Blood Flow.

BACKGROUND: Neonates with ductal-dependent pulmonary blood flow (DD-PBF) are at risk for pulmonary artery (PA) stenosis. The objective of this study was to identify preoperative cardiovascular computed tomography angiography (CTA) measures that are associated with the need for branch PA intervention. METHODS: We identified neonates with DD-PBF who underwent preoperative CTA at our center and were followed for 24 months. The primary outcome was requiring intervention for branch PA stenosis at the initial or subsequent procedure. Patients were divided into three groups: 1) No PA intervention, 2) Initial PA intervention, and 3) Remote PA intervention. Measurements of the branch PAs and patent ductus arteriosus (PDA) were made prospectively. RESULTS: Forty patients were included, 7 (18%) did not receive a PA intervention, 23 (58%) were in the initial PA intervention group, and 10 (25%) were in the remote PA intervention group. The distance from PA bifurcation to the largest diameter of the PA that receives the PDA showed a difference between the no-intervention group versus the initial and remote intervention groups (0.8 mm [IQR 0.7, 2.0], 8.2 mm [IQR 1.9, 13.7], 8.5 mm [IQR 6.5, 11.1], respectively, P = .02). The receiver operating characteristic curve showed a distance >2.2 mm had a sensitivity = 91% and specificity = 86% in predicting the need for PA intervention. CONCLUSION: The distance from the PA bifurcation to the largest diameter of the branch PA that accepts the PDA on preoperative CTA is highly predictive of the need for initial or remote PA intervention in this group. Preoperative CTA should be considered for risk stratification in neonates undergoing intervention for DD-PBF.

Proposed competencies for the performance of cardiovascular computed tomography in pediatric and adult congenital heart disease.

Cardiovascular computed tomography (CCT) is rated appropriate by published guidelines for the initial evaluation and follow up of congenital heart disease (CHD) and is an essential modality in cardiac imaging programs for patients of all ages. However, no recommended core competencies exist to guide CCT in CHD imaging training pathways, curricula development, or establishment of a more formal educational platform. To fill this gap, a group of experienced congenital cardiac imagers, intentionally inclusive of adult and pediatric cardiologists and radiologists, was formed to propose core competencies fundamental to the expert-level performance of CCT in pediatric acquired and congenital heart disease and adult CHD. The 2020 SCCT Guideline for Training Cardiology and Radiology Trainees as Independent Practitioners (Level II) and Advanced Practitioners (Level III) in Cardiovascular Computed Tomography (1) for adult imaging were used as a framework to define pediatric and CHD-specific competencies. Established competencies will be immediately relevant for advanced cardiac imaging fellowships in both cardiology and radiology training pathways. Proposed future steps include radiology and cardiology society collaboration to establish provider certification levels, training case-volume recommendations, and continuing medical education (CME) requirements for expert-level performance of CCT in pediatric and adult CHD.

Developmental aortic arch anomalies in infants and children assessed with CT angiography.

OBJECTIVE: The purpose of this article is to review the normal anatomy of the aortic arch and the most common variations of congenital aortic arch anomalies using low-radiation-dose, defined as a dose-length product of 7-15 mGy × cm, MDCT angiography. CONCLUSION: Radiologists should be prepared to fully describe congenital aortic arch anomalies; recognize them on CT angiography, especially the presence or absence of vascular rings or aberrant arteries; and explain their association with the trachea and esophagus.

Challenges in echocardiographic assessment of mitral regurgitation in children after repair of atrioventricular septal defect.

The validity and reproducibility of echocardiographic methods used to quantify mitral regurgitation (MR) in children with congenital heart disease are unknown. We evaluated the usefulness of methods used to quantify MR in children enrolled in a multicenter trial of enalapril 6 months after surgical repair of an atrioventricular septal defect (AVSD). MR severity in this trial was assessed using body surface area (BSA)-adjusted vena contracta lateral (i-VCW(lat)) and anterior-posterior (i-VCW(ap)) dimensions and cross-sectional area (i-VCA), regurgitant volume/BSA, regurgitant fraction, and qualitative MR grade. For each method, association with left ventricular end-diastolic volume (LVEDVz) and end-diastolic dimension (LVEDDz) z-scores and interobserver agreement were assessed. In 149 children (median age 1 year), i-VCW(lat), i-VCW(ap), and i-VCA were best associated with LVEDVz (r (2) = 0.54, r (2) = 0.24, and r (2) = 0.46, respectively; p < 0.001 for all) and showed the highest interobserver agreement (intraclass correlation coefficient = 0.62, 0.73, and 0.68, respectively). Qualitative MR grade was also associated with LVEDVz (r (2) = 0.31, p < 0.001) and showed modest interobserver agreement (kappa 0.56). Regurgitant volume/BSA and regurgitant fraction were associated with LVEDVz (r (2) = 0.45 and r (2) = 0.45, p < 0.001 for both) but showed poor interobserver agreement [ICC = 0.28 (n = 91) and ICC = 0.17 (n = 76), respectively], and their values were negative in 75% of subjects. In conclusion, echocardiographic assessment of MR severity after AVSD remains challenging. Among the quantitative methods used in this trial, i-VCW and i-VCA performed the best but offered little advantage compared with qualitative MR grade. The utility of regurgitant volume and fraction was severely limited by poor interobserver agreement and frequently negative values.