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The Residual Lesion Score is a novel tool for assessing the achievement of surgical objectives in congenital heart surgery based on widely available clinical and echocardiographic characteristics. This article describes the methodology used to develop the Residual Lesion Score from the previously developed Technical Performance Score for five common congenital cardiac procedures using the RAND Delphi methodology.
A panel of 11 experts from the field of paediatric and congenital cardiology and cardiac surgery, 2 co-chairs, and a consultant were assembled to review and comment on validity and feasibility of measuring the sub-components of intraoperative and discharge Residual Lesion Score for five congenital cardiac procedures. In the first email round, the panel reviewed and commented on the Residual Lesion Score and provided validity and feasibility scores for sub-components of each of the five procedures. In the second in-person round, email comments and scores were reviewed and the Residual Lesion Score revised. The modified Residual Lesion Score was scored independently by each panellist for validity and feasibility and used to develop the “final” Residual Lesion Score.
The Residual Lesion Score sub-components with a median validity score of ≥7 and median feasibility score of ≥4 that were scored without disagreement and with low absolute deviation from the median were included in the “final” Residual Lesion Score.
Using the RAND Delphi methodology, we were able to develop Residual Lesion Score modules for five important congenital cardiac procedures for the Pediatric Heart Network’s Residual Lesion Score study.
This study examined longitudinal associations between performance on the Rey–Osterrieth Complex Figure–Developmental Scoring System (ROCF-DSS) at 8 years of age and academic outcomes at 16 years of age in 133 children with dextro-transposition of the great arteries (d-TGA).
The ROCF-DSS was administered at the age of 8 and the Wechsler Individual Achievement Test, First and Second Edition (WIAT/WIAT-II) at the ages of 8 and 16, respectively. ROCF-DSS protocols were classified by Organization (Organized/Disorganized) and Style (Part-oriented/Holistic). Two-way univariate (ROCF-DSS Organization × Style) ANCOVAs were computed with 16-year academic outcomes as the dependent variables and socioeconomic status (SES) as the covariate.
The Organization × Style interaction was not statistically significant. However, ROCF-DSS Organization at 8 years was significantly associated with Reading, Math, Associative, and Assembled academic skills at 16 years, with better organization predicting better academic performance.
Performance on the ROCF-DSS, a complex visual-spatial problem-solving task, in children with d-TGA can forecast academic performance in both reading and mathematics nearly a decade later. These findings may have implications for identifying risk in children with other medical and neurodevelopmental disorders affecting brain development.
Over the last two decades, heart centres have developed strategies to meet the neurodevelopmental needs of children with congenital heart disease. Since the publication of guidelines in 2012, cardiac neurodevelopmental follow-up programmes have become more widespread. Local neurodevelopmental programmes, however, have been developed independently in widely varying environments. We sought to characterise variation in structure and personnel in cardiac neurodevelopmental programmes. A 31-item survey was sent to all member institutions of the Cardiac Neurodevelopmental Outcome Collaborative. Multidisciplinary teams at each centre completed the survey. Responses were compiled in a descriptive fashion. Of the 29 invited centres, 23 responded to the survey (79%). Centres reported more anticipated neurodevelopment visits between birth and 5 years of age (median 5, range 2–8) than 5–18 years (median 2, range 0–10) with 53% of centres lacking any standard for routine neurodevelopment evaluations after 5 years of age. Estimated annual neurodevelopment clinic volume ranged from 85 to 428 visits with a median of 16% of visits involving children >5 years of age. Among responding centres, the Bayley Scales of Infant and Toddler Development and Wechsler Preschool and Primary Scale of Intelligence were the most routinely used tests. Neonatal clinical assessment was more common (64%) than routine neonatal brain imaging (23%) during hospitalisation. In response to clinical need and published guidelines, centres have established formal cardiac neurodevelopment follow-up programmes. Centres vary considerably in their approaches to routine screening and objective testing, with many centres currently focussing their resources on evaluating younger patients.
Registry-based trials have emerged as a potentially cost-saving study methodology. Early estimates of cost savings, however, conflated the benefits associated with registry utilisation and those associated with other aspects of pragmatic trial designs, which might not all be as broadly applicable. In this study, we sought to build a practical tool that investigators could use across disciplines to estimate the ranges of potential cost differences associated with implementing registry-based trials versus standard clinical trials.
We built simulation Markov models to compare unique costs associated with data acquisition, cleaning, and linkage under a registry-based trial design versus a standard clinical trial. We conducted one-way, two-way, and probabilistic sensitivity analyses, varying study characteristics over broad ranges, to determine thresholds at which investigators might optimally select each trial design.
Registry-based trials were more cost effective than standard clinical trials 98.6% of the time. Data-related cost savings ranged from $4300 to $600,000 with variation in study characteristics. Cost differences were most reactive to the number of patients in a study, the number of data elements per patient available in a registry, and the speed with which research coordinators could manually abstract data. Registry incorporation resulted in cost savings when as few as 3768 independent data elements were available and when manual data abstraction took as little as 3.4 seconds per data field.
Registries offer important resources for investigators. When available, their broad incorporation may help the scientific community reduce the costs of clinical investigation. We offer here a practical tool for investigators to assess potential costs savings.
The Single Ventricle Reconstruction Trial randomised neonates with hypoplastic left heart syndrome to a shunt strategy but otherwise retained standard of care. We aimed to describe centre-level practice variation at Fontan completion.
Centre-level data are reported as median or median frequency across all centres and range of medians or frequencies across centres. Classification and regression tree analysis assessed the association of centre-level factors with length of stay and percentage of patients with prolonged pleural effusion (>7 days).
The median Fontan age (14 centres, 320 patients) was 3.1 years (range from 1.7 to 3.9), and the weight-for-age z-score was −0.56 (−1.35 + 0.44). Extra-cardiac Fontans were performed in 79% (4–100%) of patients at the 13 centres performing this procedure; lateral tunnels were performed in 32% (3–100%) at the 11 centres performing it. Deep hypothermic circulatory arrest (nine centres) ranged from 6 to 100%. Major complications occurred in 17% (7–33%). The length of stay was 9.5 days (9–12); 15% (6–33%) had prolonged pleural effusion. Centres with fewer patients (<6%) with prolonged pleural effusion and fewer (<41%) complications had a shorter length of stay (<10 days; sensitivity 1.0; specificity 0.71; area under the curve 0.96). Avoiding deep hypothermic circulatory arrest and higher weight-for-age z-score were associated with a lower percentage of patients with prolonged effusions (<9.5%; sensitivity 1.0; specificity = 0.86; area under the curve 0.98).
Fontan perioperative practices varied widely among study centres. Strategies to decrease the duration of pleural effusion and minimise complications may decrease the length of stay. Further research regarding deep hypothermic circulatory arrest is needed to understand its association with prolonged pleural effusion.
Recent years have seen an exponential increase in the variety of healthcare data captured across numerous sources. However, mechanisms to leverage these data sources to support scientific investigation have remained limited. In 2013 the Pediatric Heart Network (PHN), funded by the National Heart, Lung, and Blood Institute, developed the Integrated CARdiac Data and Outcomes (iCARD) Collaborative with the goals of leveraging available data sources to aid in efficiently planning and conducting PHN studies; supporting integration of PHN data with other sources to foster novel research otherwise not possible; and mentoring young investigators in these areas. This review describes lessons learned through the development of iCARD, initial efforts and scientific output, challenges, and future directions. This information can aid in the use and optimisation of data integration methodologies across other research networks and organisations.
The Single Ventricle Reconstruction trial randomised neonates with hypoplastic left heart syndrome to a systemic-to-pulmonary-artery shunt strategy. Patients received care according to usual institutional practice. We analysed practice variation at the Stage II surgery to attempt to identify areas for decreased variation and process control improvement.
Prospectively collected data were available in the Single Ventricle Reconstruction public-use database. Practice variation across 14 centres was described for 397 patients who underwent Stage II surgery. Data are centre-level specific and reported as interquartile ranges across all centres, unless otherwise specified.
Preoperative Stage II median age and weight across centres were 5.4 months (interquartile range 4.9–5.7) and 5.7 kg (5.5–6.1), with 70% performed electively. Most patients had pre-Stage-II cardiac catheterisation (98.5–100%). Digoxin was used by 11/14 centres in 25% of patients (23–31%), and 81% had some oral feeds (68–84%). The majority of the centres (86%) performed a bidirectional Glenn versus hemi-Fontan. Median cardiopulmonary bypass time was 96 minutes (75–113). In aggregate, 26% of patients had deep hypothermic circulatory arrest >10 minutes. In 13/14 centres using deep hypothermic circulatory arrest, 12.5% of patients exceeded 10 minutes (8–32%). Seven centres extubated 5% of patients (2–40) in the operating room. Postoperatively, ICU length of stay was 4.8 days (4.0–5.3) and total length of stay was 7.5 days (6–10).
In the Single Ventricle Reconstruction Trial, practice varied widely among centres for nearly all perioperative factors surrounding Stage II. Further analysis may facilitate establishing best practices by identifying the impact of practice variation.
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.
Objectives: Although evidence exists of broadly defined memory impairment among adolescents with critical congenital heart disease (CHD), nuanced investigations of declarative memory in this at-risk population have not been conducted. This study had two primary aims: (1) to conduct a fine-grained analysis of a range of relevant learning and memory processes in adolescents with critical biventricular CHD, and (2) to identify risk, odds, and predictors of memory impairment. Methods: Data were combined from two single-center studies of neurodevelopmental outcomes in critical CHD. Two-hundred seven adolescents (Mage=15.61±1.0 years) with critical CHD (139 with dextro-transposition of the great arteries and 68 with tetralogy of Fallot without an identified genetic condition), as well as 61 healthy referents (Mage=15.27±1.1 years) completed a neuropsychological evaluation which included the Children’s Memory Scale. Results: Whereas visual-spatial memory deficits were found in both CHD subgroups, verbal memory abilities were relatively preserved. Adolescents with CHD demonstrated stronger memory for Stories than Word Pairs, t (203)=2.63, p=.009, and for Dot Locations than Faces, t(204)=−2.57, p=.01. CHD subgroup, socioeconomic status, sex, and seizure history were among the most frequent significant predictors of memory impairment. Seizure history, in particular, was associated with a 2 to 3 times greater odds of impaired performance on learning and memory tasks. Conclusions: Adolescents with critical biventricular CHD are at risk for deficits in aspects of declarative memory. Independent risk factors for worse outcome include history of seizures. (JINS, 2017, 23, 627–639)
New paediatric cardiology trainees are required to rapidly assimilate knowledge and gain clinical skills to which they have limited or no exposure during residency. The Pediatric Cardiology Fellowship Boot Camp (PCBC) at Boston Children’s Hospital was designed to provide incoming fellows with an intensive exposure to congenital cardiac pathology and a broad overview of major areas of paediatric cardiology practice.
The PCBC curriculum was designed by core faculty in cardiac pathology, echocardiography, electrophysiology, interventional cardiology, exercise physiology, and cardiac intensive care. Individual faculty contributed learning objectives, which were refined by fellowship directors and used to build a programme of didactics, hands-on/simulation-based activities, and self-guided learning opportunities.
A total of 16 incoming fellows participated in the 4-week boot camp, with no concurrent clinical responsibilities, over 2 years. On the basis of pre- and post-PCBC surveys, 80% of trainees strongly agreed that they felt more prepared for clinical responsibilities, and a similar percentage felt that PCBC should be offered to future incoming fellows. Fellows showed significant increase in their confidence in all specific knowledge and skills related to the learning objectives. Fellows rated hands-on learning experiences and simulation-based exercises most highly.
We describe a novel 4-week-long boot camp designed to expose incoming paediatric cardiology fellows to the broad spectrum of knowledge and skills required for the practice of paediatric cardiology. The experience increased trainee confidence and sense of preparedness to begin fellowship-related responsibilities. Given that highly interactive activities were rated most highly, boot camps in paediatric cardiology should strongly emphasise these elements.
The Fellowship Program of the Department of Cardiology at Boston Children’s Hospital seeks to train academically oriented leaders in clinical care and laboratory and clinical investigation of cardiovascular disease in the young. The core clinical fellowship involves 3 years in training, comprising 24 months of clinical rotations and 12 months of elective and research experience. Trainees have access to a vast array of research opportunities – clinical, basic, and translational. Clinical fellows interested in basic science may reverse the usual sequence and start their training in the laboratory, deferring clinical training for 1 or more years. An increasing number of clinical trainees apply to spend a fourth year as a senior fellow in one of the subspecialty areas of paediatric cardiology. From the founding of the Department to the present, we have maintained a fundamental and unwavering commitment to training and education in clinical care and research in basic science and clinical investigation, as well as to the training of outstanding young clinicians and investigators.
Children and adolescents with critical cyanotic congenital heart disease (CHD) are at risk for deficits in aspects of executive function (EF). The primary aim of this investigation was to compare EF outcomes in three groups of children/adolescents with severe CHD and controls (ages 10–19 years). Participants included 463 children/adolescents with CHD [dextro-transposition of the great arteries (TGA), n=139; tetralogy of Fallot (TOF), n=68; and, single-ventricle anatomy requiring Fontan procedure (SVF), n=145] and 111 controls, who underwent laboratory and informant-based evaluation of EF skills. Rates of EF impairment on D-KEFS measures were nearly twice as high for CHD groups (75–81%) than controls (43%). Distinct EF profiles were documented between CHD groups on D-KEFS tasks. Deficits in flexibility/problem-solving and verbally mediated EF skills were documented in all three CHD groups; visuo-spatially mediated EF abilities were impaired in TOF and SVF groups, but preserved in TGA. Parent, teacher, and self-report ratings on the BRIEF highlighted unique patterns of metacognitive and self-regulatory concerns across informants. CHD poses a serious threat to EF development. Greater severity of CHD is associated with worse EF outcomes. With increased understanding of the cognitive and self-regulatory vulnerabilities experienced by children and adolescents with CHD, it may be possible to identify risks early and provide individualized supports to promote optimal neurodevelopment. (JINS, 2014, 20, 34–49)
Background: Few data are available on the neuropsychological, behavioural, or structural brain imaging outcomes in adolescents who underwent corrective surgery in infancy for tetralogy of Fallot. Methods: In this single-centre cross-sectional study, we enrolled 91 adolescents (13–16 years old) with tetralogy of Fallot and 87 referent subjects. Assessments included tests of academic achievement, memory, executive functions, visual-spatial skills, attention, and social cognition, as well as brain magnetic resonance imaging. Results: Genetic abnormalities or syndromes were present in 25% of tetralogy of Fallot patients, who had markedly greater neuropsychological morbidities than did patients without a syndrome. However, even patients without a syndrome performed significantly worse than the referent group or population norms in all of the neuropsychological domains assessed. In multivariable regression in those without a genetic/phenotypic syndrome, the strongest predictors of adverse late neurodevelopmental outcomes included a greater number of complications at the first operation, more total surgical complications across all operations, and occurrence of post-operative seizures. The presence of at least one abnormality on structural magnetic resonance imaging was more frequent in tetralogy of Fallot patients than the referent group (42% versus 8%). Conclusions: Adolescents with tetralogy of Fallot are at increased neurodevelopmental risk and would benefit from ongoing surveillance and educational supports even after childhood.
Purpose: The aim of this study was to compare associations between generic versus disease-specific functional health status assessments and patient and clinical characteristics for patients with severe congenital heart disease. Methods: This was a cross-sectional observational study involving 325 single ventricle patients, aged 10–18 years, after Fontan procedure. Enrolled patients underwent a medical history review, laboratory testing, and assessment of the functional health status by completion of the generic Child Report Child Health Questionnaire and the disease-specific Congenital Heart Adolescent and Teenage questionnaire. Correlated conceptually equivalent domains from both questionnaires were identified and their associations with patient and clinical variables were compared. Results: From the generic assessment, patients perceived marginally lower physical functioning (p = 0.05) but greater freedom from bodily pain compared with a normal population (p < 0.001). The equivalent physical functioning/limitations domain of the generic instrument, compared with the disease-specific instrument, had similar associations (higher multi-variable model R2) with medical history variables (R2 = 0.14 versus R2 = 0.12, respectively) and stronger associations with exercise testing variables (R2 = 0.22 versus R2 = 0.06). Similarly, the corresponding freedom from bodily pain/symptoms domains from both questionnaires showed a greater association for the generic instrument with medical history variables (R2 = 0.15 versus R2 = 0.09, respectively) and non-cardiac conditions (R2 = 0.13 versus R2 = 0.06). The associations of each questionnaire with echocardiographic results, cardiac magnetic resonance imaging results, and serum brain natriuretic peptide levels were uniformly weak (R2 range <0.01 to 0.04). Conclusions: Assessment of the physical functional health status using generic and disease-specific instruments yields few differences with regard to associations between conceptually similar domains and patient and clinical characteristics for adolescents after Fontan procedure.
We are honoured to provide a tribute to Dr Donald Fyler in Cardiology in the Young on the occasion of his induction into the Paediatric Cardiology Hall of Fame. Among his extraordinary contributions to paediatric cardiovascular disease, he described the epidemiology of congenital heart disease; created the framework for regionalised data collection, collaboration, and care in New England; and designed a standardised system of codes for congenital heart disease in wide use today.
Despite improvements in outcomes after completion of the Fontan circulation, long-term functional state varies. We sought to identify pre- and postoperative characteristics associated with overall function.
Methods and Results
We analyzed data from 476 survivors with the Fontan circulation enrolled in the Pediatric Heart Network Fontan Cross-sectional Study. Mean age at creation of the Fontan circulation was 3.4 plus or minus 2.1 years, with a range from 0.7 to 17.5 years, and time since completion was 8.7 plus or minus 3.4 years, the range being from 1.1 to 17.3 years. We calculated a functional score for the survivors by averaging the percentile ranks of ventricular ejection fraction, maximal consumption of oxygen, the physical summary score for the Child Health Questionnaire, and a function of brain natriuretic peptide. The mean calculated score was 49.5 plus or minus 17.3, with a range from 3 to 87. After adjustment for time since completion of the circulation, we found that a lower score, and hence worse functional state, was associated with: right ventricular morphology (p less than 0.001), higher ventricular end-diastolic pressure (p equals 0.003) and lower saturations of oxygen (p equals 0.047) prior to completion of the Fontan circulation, lower income for the caregiver (p equals 0.003), and, in subjects without a prior superior cavopulmonary anastomosis, arrhythmias after completion of the circulation (p equals 0.003). The model explained almost one-fifth (18%) of the variation in the calculated scores. The score was not associated with surgical centre, sex, age, weight, fenestration, or the period of stay in hospital after completion of the Fontan circuit. A validation model, using 71 subjects randomly excluded from initial analysis, weakly correlated (R equals 0.17, p equals 0.16) with the score calculated from the dataset.
Right ventricular morphology, higher ventricular end-diastolic pressure and lower saturations of oxygen prior to completion of the Fontan circuit, lower income for the provider of care, and arrhythmias after creation of the circuit, are all associated with a worse functional state. Unmeasured factors also influence outcomes.
Uncertainty exists regarding the degree to which infants with congenitally malformed hearts are at risk of behavioural disorders in childhood. Data was collected as part of a randomized clinical trial involving 155 children with surgically corrected transposition (concordant atrioventricular and ventriculo-arterial connections or alignments). As infants, they underwent the arterial switch operation, involving deep hypothermia with predominantly total circulatory arrest or predominantly low-flow continuous cardiopulmonary bypass as the method of providing support to the vital organs. Parents completed the Child Behavior Checklist when the patients were aged 4 and 8 years, and the Connors’ Parent Rating Scale at the age of 8 years. When the children were aged 8, teachers completed the Teacher’s Report Form and the Connors’ Teacher Rating Scale. In the cohort as a whole, the frequencies of behavioural problems identified by both parents and teachers were elevated, particularly on the scales for competence of the Child Behavior Checklist, and the Adaptive scales of the Teacher’s Report Form. Approximately 1 in 5 patients had scores for Total Problem Behavior in the range of clinical concern on both the Child Behavior Checklist and the Teacher’s Report Form. Few differences were found, however, according to the method of operative treatment. Postoperative seizures were associated with social and attention problems. Children experiencing academic problems at the age of 8 showed a larger increase in behavioural problems between the ages of 4 and 8 than did children making adequate academic progress. Children with congenitally malformed hearts who underwent reparative surgery in infancy using a strategy of severe haemodilution and alpha stat are at increased risk of behavioural problems in middle childhood.
Kawasaki disease is an acute vasculitis of unknown etiology that occurs predominantly in infancy and early childhood. It is characterize by fever, bilateral nonexudative conjunctivitis, erythema of the lips and oral mucosa, changes in the extremities, rash, and cervical lymphadenopathy.1,2 Coronary arterial aneurysms, or ectasia, develop in approximately 15 to 25% of children with the disease, and may lead to myocardial infarction, sudden death, or chronic coronary arterial insufficiency.2–4
The dramatic reduction in surgical mortality associated with repair of congenital heart anomalies in recent decades has been accompanied by a growing recognition of adverse neurologic sequels in some of the survivors. Abnormalities of the central nervous system may be a function of coexisting cerebral abnormalities or acquired events unrelated to surgical management (such as paradoxical embolus, cerebral infection, or effects of chronic cyanosis), but insults to the central nervous system appear to occur most frequently during or immediately after surgery. In particular, techniques of support used during neonatal and infant cardiac surgery—cardiopulmonary bypass, profound hypothermia and circulatory arrest—have been implicated as important causes of cerebral injury. This paper will review the effects of bypass and deep hypothermic circulatory arrest on neurodevelopmental outcome.
Background: Surgical intervention for children with congenital cardiac disease in the developing world often occurs late. Our objective was to identify factors that placed Guatemalan children at risk for delayed care. Methods: We investigated the medical and socioeconomic background of 178 children under the age of 18 years who received their first corrective surgery for congenital cardiac disease at the Unidad de Cirugía Cardiovascular de Guatemala in 2002. A retrospective review of medical records was performed. Each case was stratified into one of three surgical classes based upon customary practice in the United States of America. The outcome we measured was age at surgery, adjusting for the surgical class. Logistic regression was performed and odds ratios calculated. Results: In univariate analyses, patients presented later for surgery if they were from rural areas (p equals 0.001), did not have social security membership (p equals 0.004), or paid any amount towards the cost of their surgery (p less than 0.001). Age at surgery was also positively correlated with the distance of the home of the patient from the surgical centre (p equals 0.002). For the subset of patients who applied for financial assistance, we found that children presented later for surgery if they required institutional support (p equals 0.001), or came from households of larger size (p less than 0.001). Conclusions: Guatemalan children with congenital cardiac disease may be at risk for delayed surgical care if they come from rural areas, areas distant from the surgical centre, or from families without membership of social security.