Unstable right ventricular hypertension in pulmonary atresia and intact ventricular septum: a case report.

Arterial oxygen saturation in single ventricle patients is dependent on systemic cardiac output. Here, we describe a case of a newborn with single ventricle physiology and an unusual mechanism to explain poor cardiac output and cyanosis. This case highlights the importance of identifying and considering ventricular morphology and ventricular-ventricular interactions to understand clinical challenges.

Training on Congenital 3D Cardiac Models - Will Models Improve Surgical Performance?

Technical skill development in congenital heart surgery (CHS) is challenging due to numerous factors which potentially limit the hands-on operative exposure in surgical training. These challenges have stimulated the growth of simulation-based training through the development of 3D-printed models, providing hands-on surgical training (HOST). From its inception in 2015, the models used in the HOST program have constantly improved, and now include valvar/subvalvar apparatus and better materials that mimic real tissue. Evidence shows that deliberate, regular simulation practice can improve a surgeon's technical skills across the spectrum of CHS. Furthermore, surgical trainees who undergo simulation training are able to translate this improved performance into the operative environment with improved patient outcomes. Despite evidence to support the incorporation of simulation methods into congenital training, its widespread adoption into training curricula remains low. This is due to numerous factors including funding, lack of dedicated time or proctorship and access to models-all of which can be overcome with the newer generation of models and committed trainers. Training programs should consider incorporating simulation-methods as a routine component of congenital training programs.

Medium-term Outcome of Prenatally Diagnosed Hypoplastic Left-Heart Syndrome and Impact of a Restrictive Atrial Septum Diagnosed in-utero.

OBJECTIVE: Surgical outcome data differs from overall outcomes of prenatally diagnosed fetuses with hypoplastic left heart syndrome (HLHS). Our aim was to describe outcome of prenatally diagnosed fetuses with this anomaly. METHODS: Retrospective review of prenatally diagnosed classical HLHS at a tertiary hospital over a 13-year period, estimated due dates 01/08/2006 to 31/12/2019. HLHS-variants and ventricular disproportion were excluded. RESULTS: 203 fetuses were identified with outcome information available for 201. There were extra-cardiac abnormalities in 8% (16/203), with genetic variants in 14% of those tested (17/122). There were 55 (27%) terminations of pregnancy, 5 (2%) intrauterine deaths and 10 (5%) babies had prenatally planned compassionate care. There was intention to treat (ITT) in the remaining 131/201(65%). Of these, there were 8 neonatal deaths before intervention, two patients had surgery in other centers. Of the other 121 patients, Norwood procedure performed in 113 (93%), initial hybrid in 7 (6%), and 1 had palliative coarctation stenting. Survival for the ITT group from birth at 6-months, 1-year and 5-years was 70%, 65%, 62% respectively. Altogether of the initial 201 prenatally diagnosed fetuses, 80 patients (40%) are currently alive. A restrictive atrial septum (RAS) is an important sub-category associated with death, HR 2.61, 95%CI 1.34-5.05, p = 0.005, with only 5/29 patients still alive. CONCLUSION: Medium-term outcomes of prenatally diagnosed HLHS have improved however it should be noted that almost 40% do not get to surgical palliation, which is vital to those doing fetal counselling. There remains significant mortality particularly in fetuses with in-utero diagnosed RAS.

Congenital Heart Surgery Skill Training Using Simulation Models: Not an Option but a Necessity.

Congenital heart surgery (CHS) is technically demanding, and its training is extremely complex and challenging. Training of the surgeon's technical skills has relied on a preceptorship format in which the trainees are gradually exposed to patients in the operating room under the close tutelage of senior staff surgeons. Training in the operating room is an inefficient process and the concept of a learning curve is no longer acceptable in terms of patient outcomes. The benefits of surgical simulation in training of congenital heart surgeons are well known and appreciated. However, adequate surgical simulation models and equipment for training have been scarce until the recent development of three-dimensionally (3D) printed models. Using comprehensive 3D printing and silicone-molding techniques, realistic simulation training models for most congenital heart surgical procedures have been produced. Newly developed silicone-molded models allow efficient CHS training in a stress-free environment with instantaneous feedback from the proctors and avoids risk to patients. The time has arrived when all congenital heart surgeons should consider surgical simulation training before progressing to real-life operating in a similar fashion to the aviation industry where all pilots are required to complete simulation training before flying a real aircraft. It is argued here that simulation training is not an option anymore but should be a mandatory component of CHS training.

How and When Should Tetralogy of Fallot be Palliated Prior to Complete Repair?

The controversy regarding the best or ideal surgical management of Tetralogy of Fallot (ToF) stems from the recognition of there being a spectrum of morphology and associated lesions, each of which require a different approach to achieve the three goals of minimizing mortality preserving right ventricular function long-term and minimizing reinterventions. A one-size-fits-all approach to ToF needs to be replaced by a considered and personalized approach in order to yield the best outcomes possible for individual patients. The great majority of patients with ToF undergo primary complete repair between age 3-9 months with excellent outcomes. However, the greatest challenge is the severely cyanotic neonates where primary repair is still associated with high mortality and reintervention rates. Risk factors are low weight and small/poorly developed pulmonary vasculature. High-risk neonates have better outcomes with palliation-but mortality is still high. Palliative interventions in the catherization lab are showing better outcomes than traditional BT shunt and the RVOT stent is emerging as potential game-changer. Primary neonatal repair is still recommended if weight >3 kg and Nakata >100 mm2/m2. However, neonates with low weight, small pulmonary arteries or multiple comorbidities (including ToF/AVSD and anomalous LAD) may do better with a staged approach, There is good argument for RVOT stenting as a bridge to complete repair due to its stable circulation without diastolic run off and volume loading of the circulation, and its potential to allow branch PA growth.

Predicting the Future: Tetralogy of Fallot Will Be Primarily Treated with Catheter Based Intervention Within Two Decades. Surgeon's Perspective.

Interventional cardiology has made extraordinary advances over recent years, but most are still limited to addressing single intracardiac or valvular lesions. This debate considers whether complete interventional repair of more complex congenital defects might become achievable. Tetralogy of Fallot (ToF) is probably the first candidate where complete interventional repair might be achieved-given that various components of the defect have already been successfully addressed-albeit as either a palliative intervention (RVOT stenting) or to address the sequelae of standard surgery (percutaneous PVR). This article considers the challenges that would need to be overcome in terms of the morphology of the condition, the age limitations, and the necessary technological advancements that would be required-while setting these against the benchmark of current surgical outcomes and the parallel progress that is being developed in surgical correction. While complete interventional repair of ToF may still be beyond current techniques, a hybrid approach between surgeons and intentional cardiologists can strive to create a life-long paradigm of care that minimizes the need for surgery and focuses on the maintenance of a healthy right ventricle, such that patients born with ToF can achieve normal life expectancy.

A tool for routine monitoring and feedback of morbidities following paediatric cardiac surgery.

Short-term survival after paediatric cardiac surgery has improved significantly over the past 20 years and increasing attention is being given to measuring and reducing incidence of morbidities following surgery. How to best use routinely collected data to share morbidity information constitutes a challenge for clinical teams interested in analysing their outcomes for quality improvement. We aimed to develop a tool facilitating this process in the context of monitoring morbidities following paediatric cardiac surgery, as part of a prospective multi-centre research study in the United Kingdom.We developed a prototype software tool to analyse and present data about morbidities associated with cardiac surgery in children. We used an iterative process, involving engagement with potential users, tool design and implementation, and feedback collection. Graphical data displays were based on the use of icons and graphs designed in collaboration with clinicians.Our tool enables automatic creation of graphical summaries, displayed as a Microsoft PowerPoint presentation, from a spreadsheet containing patient-level data about specified cardiac surgery morbidities. Data summaries include numbers/percentages of cases with morbidities reported, co-occurrences of different morbidities, and time series of each complication over a time window.Our work was characterised by a very high level of interaction with potential users of the tool, enabling us to promptly account for feedback and suggestions from clinicians and data managers. The United Kingdom centres involved in the project received the tool positively, and several expressed their interest in using it as part of their routine practice.

Match performance in a reference futsal team during an international tournament - implications for talent development in soccer.

Anecdotal evidence suggests that futsal can aid talent development for 11 a-side soccer through the potential for transfer of the game's skills and constraints. However, additional scientific research is necessary to enhance understanding of the technical and physical demands of futsal and the potential returns for soccer player development. Accordingly, this study examined selected characteristics of physical (internal and external loads) and technical performance in international futsal match-play in order to study the potential of these for skill transfer and aiding soccer player development. Performance was investigated in futsal players (n = 16, 25.74±4.71 years) belonging to a national team during an international tournament. Pre-tournament fitness testing determined maximum heart rate (MHR) via the Yo-Yo IR1 test (194.6±11.1 beats min-1) to aid interpretation of internal load via heart rate measures during match-play. External load (accelerations and deceleration events) was measured using an inertial movement unit. Finally, post-tournament analysis of selected technical events was performed. Results reported a mean heart rate value during 'court time' of 164.7±22.3 beats min-1, which as a percentage of participants' MHR was 87.7%±4.4%, and a mean peak MHR of 98.3±2.5%. Results showed 2.16±0.25 accelerating (>1.5 m·s-2) and 2.78±0.13 decelerating (>1.5 m·s-2) events per player per minute. Team statistics included 647 passing, ~51 dribbling and 78 set play events per team per game. Match analyses showed that 77.3% of ball receptions were completed with the sole of the foot. Assessment of two-footedness showed 80.1±16.7% of individual possessions used the dominant foot to receive and 84.1±10.7% to pass the ball thereby displaying strong foot dominance. These results have quantified characteristics of elite futsal match-play that are no doubt intrinsically related to the environmental and task constraints of the sport. In addition to enhancing understanding of futsal, there are potential learning returns and implications for skills transfer and the development of soccer players.

Left Ventricular Re-training: Feasibility and Effectiveness-What Are the Limits?

The concept of 're-training' the morphologic left ventricle (mLV) is based on the crude principle of applying a fixed afterload by means of pulmonary artery banding. The complex physiological, molecular and structural responses to banding are poorly understood, and complicated by the fact that re-training is undertaken in a variety of different morphological settings and age-groups. This article reviews the evidence for re-training in different situations with particular focus on the age at banding and on the best ways to assess suitability for subsequent repair. Particular importance is placed on the role of re-training in congenitally corrected transposition as this is the commonest current indication - looking at better ways to train the mLV, the role of combined pressure and volume loading, and more sophisticated ways of assessing the adequacy of training. Current evidence suggests that age at banding has a fundamental impact on ability to re-train and long-term mLV function with the best results being achieved in infancy and concerns at any attempt beyond 2 years of age.

Approaches to Pulmonary Atresia With Major Aortopulmonary Collateral Arteries.

Pulmonary atresia with major aortopulmonary collateral arteries (MAPCAs) is one of the most challenging surgical conditions to manage-not only because of the technical complexity of the surgery but also in terms of defining the anatomy of the pulmonary vasculature, the timing of surgery, and decision making on staged vs complete repair. The importance of early definition of pulmonary blood supply is paramount, establishing which areas of the lung are supplied by MAPCAs alone and which have dual supply with the native system (noting that 20% of patients have absent intrapericardial native vessels). Early unifocalization (3-6 months) is ideal, with closure of the ventricular septal defect (VSD) performed if 15 or more out of 20 lung segments can be recruited. Leaving the ventricular septal defect open with a limiting right ventricle-pulmonary artery conduit can be a useful interim or even definitive circulation in patients with borderline vasculature. Rehabilitation of small native vessels with central shunts can be very effective, but best outcomes are achieved by a combination of unifocalization of MAPCAs together with the native vessels (if present). A variety of reconstructive techniques are necessary to be able to effect these complex repairs with careful choice of materials. Ideally, surgery can be completed through sternotomy alone, but separate thoracotomies may be necessary to control and access some MAPCAs.

Parents' preparedness for their infants' discharge following first-stage cardiac surgery: development of a parental early warning tool.

UNLABELLED: Aim The aim of this study was to explore parental preparedness for discharge and their experiences of going home with their infant after the first-stage surgery for a functionally univentricular heart. BACKGROUND: Technological advances worldwide have improved outcomes for infants with a functionally univentricular heart over the last 3 decades; however, concern remains regarding mortality in the period between the first and second stages of surgery. The implementation of home monitoring programmes for this group of infants has improved this initial inter-stage survival; however, little is known about parents' experiences of going home, their preparedness for discharge, and parents' recognition of deterioration in their fragile infant. METHOD: This study was conducted in 2011-2013; eight sets of parents were consulted in the research planning stage in September, 2011, and 22 parents with children aged 0-2 years responded to an online survey during November, 2012-March, 2013. Description of categorical data and deductive thematic analysis of the open-ended questions were undertaken. RESULTS: Not all parents were taught signs of deterioration or given written information specific to their baby. The following three themes emerged from the qualitative data: mixed emotions about going home, knowledge and preparedness, and support systems. CONCLUSIONS: Parents are not adequately prepared for discharge and are not well equipped to recognise deterioration in their child. There is a role for greater parental education through development of an early warning tool to address the gap in parents' understanding of signs of deterioration, enabling appropriate contact and earlier management by clinicians.

Unexpected deaths and unplanned re-admissions in infants discharged home after cardiac surgery: a systematic review of potential risk factors.

BACKGROUND: Babies with CHDs are a particularly vulnerable population with significant mortality in their 1st year. Although most deaths occur in the hospital within the early postoperative period, around one-fifth of postoperative deaths in the 1st year of life may occur after hospital discharge in infants who have undergone apparently successful cardiac surgery. Aim To systematically review the published literature and identify risk factors for adverse outcomes, specifically deaths and unplanned re-admissions, following hospital discharge after infant surgery for life-threatening CHDs. METHODS: A systematic search was conducted in MEDLINE, EMBASE, CINAHL, Cochrane Library, Web of Knowledge, and PsycINFO electronic databases, supplemented by manual searching of conference abstracts. RESULTS: A total of 15 studies were eligible for inclusion. Almost exclusively, studies were conducted in single US centres and focussed on children with complex single ventricle diagnoses. A wide range of risk factors were evaluated, and those more frequently identified as having a significant association with higher mortality or unplanned re-admission risk were non-Caucasian ethnicity, lower socio-economic status, co-morbid conditions, age at surgery, operative complexity and procedure type, and post-operative feeding difficulties. CONCLUSIONS: Studies investigating risk factors for adverse outcomes post-discharge following diverse congenital heart operations in infants are lacking. Further research is needed to systematically identify higher risk groups, and to develop interventions targeted at supporting the most vulnerable infants within an integrated primary and secondary care pathway.

Mortality as a measure of quality of care in infants with congenital cardiovascular malformations following surgery.

INTRODUCTION: Mortality has traditionally been perceived as a straightforward measure of outcome and has been used to evaluate surgical performance. In the rapidly developing arena of paediatric cardiac surgery, the insightful analysis of mortality figures is challenging. SOURCES OF DATA: This report discusses the issues involved when mortality is used as a marker for surgical outcome, referring to national and international audit and research data. AREAS OF AGREEMENT: Mortality is an important variable and should be transparently defined, reported and monitored. AREAS OF CONTROVERSY: Definitions of mortality, assessments of risk and interpretations of reported statistics all have limitations that must be recognized. GROWING POINTS: Traditional use of raw early mortality as a simplistic indicator of outcome and performance is evolving to include risk-adjusted mortality, longer-term survival, reinterventions and complications. AREAS TIMELY FOR DEVELOPING RESEARCH: As the vast majority of children undergoing cardiac surgery now survive beyond 30 days, the focus for measures of quality is shifting towards morbidity.

Association of left ventricular outflow tract size with arch morphology in interrupted aortic arch.

OBJECTIVES: Left ventricular outflow tract obstruction (LVOTO) is a major cause of morbidity and mortality in infants with interrupted aortic arch (IAA). Left Ventricular Outflow Tract (LVOT) development may be flow-mediated, thus IAA morphology may influence LVOT diameter and subsequent reintervention. We investigated the association of IAA morphology [type and presence of aortic arch aberrancy (AAb)] with LVOT diameter and reintervention. METHODS: All surgical patients with IAA (2001-2022) were reviewed at a single institution. We compared IAA-A versus IAA-B; IAA with aortic AAb versus none; IAA-B with aberrant subclavian (AAbS) artery versus others. Primary outcomes included LVOT diameter (mm), LVOTO at discharge (≥50 mmHg), and LVOT reintervention. RESULTS: Seventy-seven infants (mean age 10 ± 19 days) were followed for 7.6 (5.5-9.7) years. Perioperative mortality was 3.9% (3/77) and long-term mortality was 5.2% (4/77). Out of 51 IAA-B (66%) and 22 IAA-A (31%) patients, 30% (n = 22) had AAb. Smaller LVOT diameter was associated with IAA-B [IAA-A: 5.40 (4.68-5.80), IAA-B: 4.60 (3.92-5.50), P = 0.007], AAb [AAb: 4.00 (3.70-5.04) versus none: 5.15 (4.30-5.68), P = 0.006], and combined IAA-B + AAbS [IAA-B + AAbS: 4.00 (3.70-5.02) versus other: 5.00 (4.30-5.68), P = 0.002]. The likelihood of LVOTO was higher among AAb [N = 6 (25%) vs N = 1 (2%), P = 0.004] and IAA-B + AAbS [N = 1 (2%) vs N = 6 (30%), P = 0.002]. Time-to-event analysis showed a signal towards increased LVOT reintervention in IAA-B + AAbS (P = 0.11). CONCLUSIONS: IAA-B and AAb are associated with small LVOT diameter and early LVOTO, especially in combination. This may reflect lower flow in the proximal arch during development. Most reinterventions occur in IAA-B + AAbS, hence these patients should be carefully considered for LVOT intervention at the time of initial repair.

Longitudinal Evaluation of Congenital Cardiovascular Surgical Performance and Skills Retention Using Silicone-Molded Heart Models.

Objective: Hands-on surgical training (HOST) for congenital heart surgery (CHS), utilizing silicone-molded models created from 3D-printing of patients' imaging data, was shown to improve surgical skills. However, the impact of repetition and frequency of repetition in retaining skills has not been previously investigated. We aimed to longitudinally evaluate the outcome for HOST on two example procedures of different technical difficulties with repeated attempts over a 15-week period. Methods: Five CHS trainees were prospectively recruited. Repair of coarctation of the aorta (CoA) and arterial switch operation (ASO) were selected as example procedures of relatively low and high technical difficulty. Procedural time and technical performance (using procedure-specific assessment tools by the participant, a peer-reviewer, and the proctor) were measured. Results: Coarctation repair performance scores improved after the first repetition but remained unchanged at the follow-up session. Likewise, CoA procedural time showed an early reduction but then remained stable (mean [standard deviation]: 29[14] vs 25[15] vs 23[9] min at 0, 1, and 4 weeks). Conversely, ASO performance scores improved during the first repetitions, but decreased after a longer time delay (>9 weeks). Arterial switch operation procedural time showed modest improvements across simulations but significantly reduced from the first to the last attempt: 119[20] versus 106[28] min at 0 and 15 weeks, P = .049. Conclusions: Complex procedures require multiple HOST repetitions, without excessive time delay to maintain long-term skills improvement. Conversely, a single session may be planned for simple procedures to achieve satisfactory medium-term results. Importantly, a consistent reduction in procedural times was recorded, supporting increased surgical efficiency.

Comparing apples to apples: Exploring public reporting of congenital cardiac surgery outcomes based on common congenital heart operations.

OBJECTIVE: We sought to simplify reporting of outcomes in congenital heart surgery that compares well-defined patient groups and accommodates multiple stakeholder needs while being easily understandable. METHODS: We selected 19 commonly performed congenital heart surgeries ranging in complexity from repair of atrial septal defects to the Norwood procedure. Strict inclusion/exclusion criteria ensured the creation of 19 well-defined diagnosis/procedure cohorts. Preoperative, procedural, and postoperative data were collected for consecutive eligible patients from 9 centers between January 1, 2016, and December 31, 2021. Unadjusted operative mortality rates and hospital length of stay for each of the 19 diagnosis/procedure cohorts were summarized in aggregate and stratified by each center. RESULTS: Of 8572 eligible cases included, numbers in the 19 diagnosis/procedure cohorts ranged from 73 for tetralogy of Fallot repair after previous palliation to 1224 for ventricular septal defect (VSD) repair for isolated VSD. In aggregate, the unadjusted mortality ranged from 0% for atrial septal defect repair to 28.4% for hybrid stage I. There was significant heterogeneity in case mix and mortality for different diagnosis/procedure cohorts across centers (eg, arterial switch operation/VSD, n = 7-42, mortality 0%-7.4%; Norwood procedure, n = 16-122, mortality 5.3%-25%). CONCLUSIONS: Reporting of institutional case volumes and outcomes within well-defined diagnosis/procedure cohorts can enable centers to benchmark outcomes, understand trends in mortality, and direct quality improvement. When made public, this type of report could provide parents with information on institutional volumes and outcomes and allow them to better understand the experience of each program with operations for specific congenital heart defects.

Incremental value of machine learning for risk prediction in tetralogy of Fallot.

OBJECTIVE: Machine learning (ML) can facilitate prediction of major adverse cardiovascular events (MACEs) in repaired tetralogy of Fallot (rTOF). We sought to determine the incremental value of ML above expert clinical judgement for risk prediction in rTOF. METHODS: Adult congenital heart disease (ACHD) clinicians (≥10 years of experience) participated (one cardiac surgeon and four cardiologists (two paediatric and two adult cardiology trained) with expertise in heart failure (HF), electrophysiology, imaging and intervention). Clinicians identified 10 high-yield variables for 5-year MACE prediction (defined as a composite of mortality, resuscitated sudden death, sustained ventricular tachycardia and HF). Risk for MACE (low, moderate or high) was assigned by clinicians blinded to outcome for adults with rTOF identified from an institutional database (n=25 patient reviews conducted by five independent observers). A validated ML model identified 10 variables for risk prediction in the same population. RESULTS: Prediction by ML was similar to the aggregate score of all experts (area under the curve (AUC) 0.85 (95% CI 0.58 to 0.96) vs 0.92 (0.72 to 0.98), p=0.315). Experts with ≥20 years of experience had superior discriminative capacity compared with <20 years (AUC 0.98 (95% CI 0.86 to 0.99) vs 0.80 (0.56 to 0.93), p=0.027). In those with <20 years of experience, ML provided incremental value such that the combined (clinical+ML) AUC approached ≥20 years (AUC 0.85 (95% CI 0.61 to 0.95), p=0.055). CONCLUSIONS: Robust prediction of 5-year MACE in rTOF was achieved using either ML or a multidisciplinary team of ACHD experts. Risk prediction of some clinicians was enhanced by incorporation of ML suggesting that there may be incremental value for ML in select circumstances.

Long-Term Enlargement of the Neo-Aortic Root and Aortic Arch Following Arch Reconstruction in Hypoplastic Left Heart Syndrome.

BACKGROUND: Long-term enlargement of the aortic arch after aortic arch reconstruction (AAR) in hypoplastic left heart syndrome (HLHS) is not well described. METHODS: Aortic arch measurements for 50 patients with HLHS who achieved Fontan completion were converted to Pediatric Heart Network z-scores. Dimensions were assessed using linear mixed models and differences among time points were evaluated with F-tests. Sub-analysis was conducted comparing Norwood (n=36) vs hybrid (n=14) strategies. RESULTS: Median time to last imaging was 6.4 (IQR, 3.5-11.3) years. Prior to intervention, the main pulmonary artery was dilated whereas the ascending aorta (AA), transverse arch (TA), and isthmus (ISTH) were hypoplastic. With AAR, there were expected increases in all arch z-scores. The aortic arch continued to dilate after AAR reaching peak values at 7 months [Neo-Aortic Complex (NAC): z= 6.9 (5.6-8.0)] or 12 months following stage I [AAo: z=6.1 (2.9-8.3); TA: z=4.7 (3.0-5.9)]. Following peak values, there was a gradual decline in z-scores with most components still at least mildly dilated at 16 years [NAC: z=3.2 (3.1-3.9), AAo: z=3.9 (3.3-4.2); TA: z=3.1 (2.5-3.7)] with abrupt calibre change at ISTH: z= -0.8 (-1.1- -0.3)]. Norwood and hybrid strategies showed similar enlargement profiles after 7 months of age. CONCLUSIONS: Neo-aortic root and aortic arch in HLHS are enlarged early after AAR and continue to enlarge out of proportion to normal controls until 12 months of age, with gradual decline in enlargement up to adolescence. Further work should focus on modifiable surgical factors which may prove important to optimize arch growth and geometry.