Interventional treatments and risk factors in patients born with hypoplastic left heart syndrome in England and Wales from 2000 to 2015

Retrospective Cohort Study of Additional Procedures and Transplant-Free Survival for Patients With Functionally Single Ventricle Disease Undergoing Staged Palliation in England and Wales

BACKGROUND

Reinterventions may influence the outcomes of children with functionally single-ventricle (f-SV) congenital heart disease.

METHODS AND RESULTS

We undertook a retrospective cohort study of children starting treatment for f-SV between 2000 and 2018 in England, using the national procedure registry. Patients were categorized based on whether they survived free of transplant beyond 1 year of age. Among patients who had transplant-free survival beyond 1 year of age, we explored the relationship between reinterventions in infancy and the outcomes of survival and Fontan completion, adjusting for complexity. Of 3307 patients with f-SV, 909 (27.5%), had no follow-up beyond 1 year of age, among whom 323 (35.3%) had ≥1 reinterventions in infancy. A total of 2398 (72.5%) patients with f-SV had transplant-free survival beyond 1 year of age, among whom 756 (31.5%) had ≥1 reinterventions in infancy. The 5-year transplant-free survival and cumulative incidence of Fontan, among those who survived infancy, were 93.4% (95% CI, 92.4%-94.4%) and 79.3% (95% CI, 77.4%-81.2%), respectively. Both survival and Fontan completion were similar for those with a single reintervention and those who had no reinterventions. Patients who had >1 additional surgery (adjusted hazard ratio, 3.93 [95% CI, 1.87-8.27] P<0.001) had higher adjusted risk of mortality. Patients who had >1 additional interventional catheter (adjusted subdistribution hazard ratio, 0.71 [95% CI, 0.52-0.96] P=0.03) had a lower likelihood of achieving Fontan.

CONCLUSIONS

Among children with f-SV, the occurrence of >1 reintervention in the first year of life, especially surgical reinterventions, was associated with poorer prognosis later in childhood.

Fetal single ventricle journey to first postnatal procedure: a multicentre UK cohort study

OBJECTIVES

UK single ventricle (SV) palliation outcomes after first postnatal procedure (FPP) are well documented. However, survival determinants from fetal diagnosis to FPP are lacking. To better inform parental-fetal counselling, we examined factors favouring survival at two large UK centres.

DESIGN

Retrospective multicentre cohort study.

SETTING

Two UK congenital cardiac centres: Leeds and Birmingham.

PATIENTS

SV fetal diagnoses from 2015 to 2021.

MAIN OUTCOME MEASURES

Survival from fetal diagnosis with intention to treat (ITT) to birth and then FPP. Maternal, fetal and neonatal risk factors were assessed.

RESULTS

There were 666 fetal SV diagnoses with 414 (62%) ITT. Of ITT, 381 (92%) were live births and 337 (81%) underwent FPP. Survival (ITT) to FPP was notably reduced for severe Ebstein's 14/22 (63.6%), unbalanced atrioventricular septal defect 32/45 (71%), indeterminate SV 3/4 (75%), mitral atresia 8/10 (80%) and hypoplastic left heart syndrome 127/156 (81.4%). Biventricular pathway was undertaken in five (1%). After multivariable adjustment, prenatal risk factors for mortality were increasing maternal age (OR 1.05, 95% CI 1.0 to 1.1), non-white ethnicity (OR 2.6, 95% CI 1.4 to 4.8), extracardiac anomaly (OR 6.34, 95% CI 1.8 to 22.7) and hydrops (OR 7.39, 95% CI 1.2 to 45.1). Postnatally, prematurity was significantly associated with mortality (OR 6.3, 95% CI 2.3 to 16.8).

CONCLUSIONS

Around 20% of ITT fetuses diagnosed with SV will not reach FPP. Risk varies according to the cardiac lesion and is significantly influenced by the presence of an extracardiac anomaly, fetal hydrops, ethnicity, increasing maternal age and gestation at birth. These data highlight the need for fetal preprocedure data to be used in conjunction with procedural outcomes for fetal counselling.

Trends in survival of children with severe congenital heart defects by gestational age at birth: A population-based study using administrative hospital data for England

BACKGROUND

Children with congenital heart defects (CHD) are twice as likely as their peers to be born preterm (<37 weeks' gestation), yet descriptions of recent trends in long-term survival by gestational age at birth (GA) are lacking.

OBJECTIVES

To quantify changes in survival to age 5 years of children in England with severe CHD by GA.

METHODS

We estimated changes in survival to age five of children with severe CHD and all other children born in England between April 2004 and March 2016, overall and by GA-group using linked hospital and mortality records.

RESULTS

Of 5,953,598 livebirths, 5.7% (339,080 of 5,953,598) were born preterm, 0.35% (20,648 of 5,953,598) died before age five and 3.6 per 1000 (21,291 of 5,953,598) had severe CHD. Adjusting for GA, under-five mortality rates fell at a similar rate between 2004-2008 and 2012-2016 for children with severe CHD (adjusted hazard ratio [HR] 0.79, 95% CI 0.71, 0.88) and all other children (HR 0.78, 95% CI 0.76, 0.81). For children with severe CHD, overall survival to age five increased from 87.5% (95% CI 86.6, 88.4) in 2004-2008 to 89.6% (95% CI 88.9, 90.3) in 2012-2016. There was strong evidence for better survival in the ≥39-week group (90.2%, 95% CI 89.1, 91.2 to 93%, 95% CI 92.4, 93.9), weaker evidence at 24-31 and 37-38 weeks and no evidence at 32-36 weeks. We estimate that 51 deaths (95% CI 24, 77) per year in children with severe CHD were averted in 2012-2016 compared to what would have been the case had 2004-2008 mortality rates persisted.

CONCLUSIONS

Nine out of 10 children with severe CHD in 2012-2016 survived to age five. The small improvement in survival over the study period was driven by increased survival in term children. Most children with severe CHD are reaching school age and may require additional support by schools and healthcare services.

Hospital resource utilization in a national cohort of functionally single ventricle patients undergoing surgical treatment

Objective

The study objective was to provide a detailed overview of health resource use from birth to 18 years old for patients with functionally single ventricles and identify associated risk factors.

Methods

All patients with functionally single ventricles treated between 2000 and 2017 in England and Wales were linked to hospital and outpatient records using data from the Linking AUdit and National datasets in Congenital HEart Services project. Hospital stay was described in yearly age intervals, and associated risk factors were explored using quantile regression.

Results

A total of 3037 patients with functionally single ventricles were included, 1409 (46.3%) undergoing a Fontan procedure. During the first year of life, the median days spent in hospital was 60 (interquartile range, 37-102), mostly inpatient days, mirroring a mortality of 22.8%. This decreases to between 2 and 9 in-hospital days/year afterward. Between 2 and 18 years, most hospital days were outpatient, with a median of 1 to 5 days/year. Lower age at the first procedure, hypoplastic left heart syndrome/mitral atresia, unbalanced atrioventricular septal defect, preterm birth, congenital/acquired comorbidities, additional cardiac risk factors, and severity of illness markers were associated with fewer days at home and more intensive care unit days in the first year of life. Only markers of early severe illness were associated with fewer days at home in the first 6 months after the Fontan procedure.

Conclusions

Hospital resource use in functionally single ventricle cases is not uniform, decreasing 10-fold during adolescence compared with the first year of life. There are subsets of patients with worse outcomes during their first year of life or with persistently high hospital use throughout their childhood, which could be the target of future research.

Long-term survival and center volume for functionally single-ventricle congenital heart disease in England and Wales

OBJECTIVES

Long-term survival is an important metric for health care evaluation, especially in functionally single-ventricle (f-SV) congenital heart disease (CHD). This study's aim was to evaluate the relationship between center volume and long-term survival in f-SV CHD within the centralized health care service of England and Wales.

METHODS

This was a retrospective cohort study of children born with f-SV CHD between 2000 and 2018, using the national CHD procedure registry, with survival ascertained in 2020.

RESULTS

Of 56,039 patients, 3293 (5.9%) had f-SV CHD. Median age at first intervention was 7 days (interquartile range [IQR], 4, 27), and median follow-up time was 7.6 years (IQR, 1.0, 13.3). The largest diagnostic subcategories were hypoplastic left heart syndrome, 1276 (38.8%); tricuspid atresia, 440 (13.4%); and double-inlet left ventricle, 322 (9.8%). The survival rate at 1 year and 5 years was 76.8% (95% confidence interval [CI], 75.3%-78.2%) and 72.1% (95% CI, 70.6%-73.7%), respectively. The unadjusted hazard ratio for each 5 additional patients with f-SV starting treatment per center per year was 1.04 (95% CI, 1.02-1.06), P < .001. However, after adjustment for significant risk factors (diagnostic subcategory; antenatal diagnosis; younger age, low weight, acquired comorbidity, increased severity of illness at first procedure), the hazard ratio for f-SV center volume was 1.01 (95% CI, 0.99-1.04) P = .28. There was strong evidence that patients with more complex f-SV (hypoplastic left heart syndrome, Norwood pathway) were treated at centers with greater f-SV case volume (P < .001).

CONCLUSIONS

After adjustment for case mix, there was no evidence that f-SV center volume was linked to longer-term survival in the centralized health service provided by the 10 children's cardiac centers in England and Wales.

Predictive factors contributing to prolonged recovery in patients after Fontan operation

Background

Prolonged recovery is a severe issue in patients after Fontan operation. However, predictive factors related to this issue are not adequately evaluated. The present study aimed to investigate potential predictive factors which can predict Fontan postoperative recovery.

Methods

We retrospectively reviewed the perioperative medical records of patients with Fontan surgery between January 2015 and December 2018, and divided patients with > 75%ile cardiac intensive care unit stay into prolonged recovery group. The others were assigned to standard recovery group. Patients that died or underwent a Fontan takedown were excluded. Statistical analysis was performed to compare data difference of the two groups.

Results

282/307 cases fulfilled the inclusion criteria. Seventy patients were considered in prolonged recovery and 212 patients were defined as standard recovery. Pre- and intra-operative data showed a higher incidence of heterotaxy syndrome, longer cardiopulmonary bypass and aortic cross-clamp time in the prolonged recovery group. Postoperative information analysis displayed that ventilation time, oxygen index after extubation, hemodynamic data, inotropic score (IS), drainage volume, volume resuscitation, pulmonary hypertension (PH) treatment, and surgical reintervention were significantly different between the two groups. Higher IS postoperatively, and PH treatment and higher fluid resuscitation within two days were independent predictive factors for prolonged recovery in our multivariate model. C-statistic model showed a high predictive ability in prolonged recovery by using the three factors.

Conclusions

Ventilation time, higher IS in postoperative day, and PH treatment and higher fluid resuscitation within two days were independent risk factors and have a high predictability for Fontan prolonged recovery.

Palliative care for children with complex cardiac conditions: survey results

OBJECTIVE

To explore perspectives of paediatric cardiac and palliative care professionals on providing palliative care to children with complex cardiac conditions.

DESIGN

A national survey including closed-ended and open-ended questions as well as clinical scenarios designed to capture referral practices, attitudes towards palliative care, confidence delivering key components of palliative care and perspectives on for whom to provide palliative care. Responses to closed-ended questions and scenarios were analysed using descriptive statistics. Open-ended responses were analysed thematically.

PARTICIPANTS

Paediatric cardiac and palliative care professionals caring for children with complex cardiac conditions in the UK.

RESULTS

177 professionals (91 cardiac care and 86 palliative care) responded. Aspects of advance care planning were the most common reasons for referral to palliative care. Palliative care professionals reported greater confidence than cardiac colleagues with such discussions. Clinicians agreed that children with no further surgical management options, comorbid genetic disorders, antenatal diagnosis of a single ventricle, ventricular device in situ, symptomatic heart failure and those awaiting heart transplantation would benefit from palliative care involvement.

CONCLUSIONS

Components of palliative care, such as advance care planning, can be provided by cardiac care professionals alongside the disease-directed care of children with complex cardiac conditions. Further research and training are needed to address confidence levels in cardiac care professionals in delivering components of palliative care as well as clarification of professional roles and parent preferences in delivery of family-centred care for children with complex cardiac conditions.

Cohort study of intervened functionally univentricular heart in England and Wales (2000-2018)

Objective

Given the paucity of long-term outcome data for complex congenital heart disease (CHD), we aimed to describe the treatment pathways and survival for patients who started interventions for functionally univentricular heart (FUH) conditions, excluding hypoplastic left heart syndrome.

Methods

We performed a retrospective cohort study using all procedure records from the National Congenital Heart Diseases Audit for children born in 2000–2018. The primary outcome was mortality, ascertained from the Office for National Statistics in 2020.

Results

Of 53 615 patients, 1557 had FUH: 55.9% were boys and 67.4% were of White ethnic groups. The largest diagnostic categories were tricuspid atresia (28.9%), double inlet left ventricle (21.0%) and unbalanced atrioventricular septal defect (AVSD) (15.2%). The ages at staged surgery were: initial palliation 11.5 (IQR 5.5–43.5) days, cavopulmonary shunt 9.2 (IQR 6.0–17.1) months and Fontan 56.2 (IQR 45.5–70.3) months. The median follow-up time was 10.8 (IQR 7.0–14.9) years and the 1, 5 and 10-year survival rates after initial palliation were 83.6% (95% CI 81.7% to 85.4%), 79.4% (95% CI 77.3% to 81.4%) and 77.2% (95% CI 75.0% to 79.2%), respectively. Higher hazards were present for unbalanced AVSD HR 2.75 (95% CI 1.82 to 4.17), atrial isomerism HR 1.75 (95% CI 1.14 to 2.70) and low weight HR 1.65 (95% CI 1.13 to 2.41), critical illness HR 2.30 (95% CI 1.67 to 3.18) or acquired comorbidities HR 2.71 (95% CI 1.82 to 4.04) at initial palliation.

Conclusion

Although treatment pathways for FUH are complex and variable, nearly 8 out of 10 children survived to 10 years. Longer-term analyses of outcome based on diagnosis (rather than procedure) can inform parents, patients and clinicians, driving practice improvements for complex CHD.

Early morbidities following paediatric cardiac surgery: a mixed-methods study

Background

Over 5000 paediatric cardiac surgeries are performed in the UK each year and early survival has improved to > 98%.

Objectives

We aimed to identify the surgical morbidities that present the greatest burden for patients and health services and to develop and pilot routine monitoring and feedback.

Design and setting

Our multidisciplinary mixed-methods study took place over 52 months across five UK paediatric cardiac surgery centres.

Participants

The participants were children aged < 17 years.

Methods

We reviewed existing literature, ran three focus groups and undertook a family online discussion forum moderated by the Children’s Heart Federation. A multidisciplinary group, with patient and carer involvement, then ranked and selected nine key morbidities informed by clinical views on definitions and feasibility of routine monitoring. We validated a new, nurse-administered early warning tool for assessing preoperative and postoperative child development, called the brief developmental assessment, by testing this among 1200 children. We measured morbidity incidence in 3090 consecutive surgical admissions over 21 months and explored risk factors for morbidity. We measured the impact of morbidities on quality of life, clinical burden and costs to the NHS and families over 6 months in 666 children, 340 (51%) of whom had at least one morbidity. We developed and piloted methods suitable for routine monitoring of morbidity by centres and co-developed new patient information about morbidities with parents and user groups.

Results

Families and clinicians prioritised overlapping but also different morbidities, leading to a final list of acute neurological event, unplanned reoperation, feeding problems, renal replacement therapy, major adverse events, extracorporeal life support, necrotising enterocolitis, surgical infection and prolonged pleural effusion. The brief developmental assessment was valid in children aged between 4 months and 5 years, but not in the youngest babies or 5- to 17-year-olds. A total of 2415 (78.2%) procedures had no measured morbidity. There was a higher risk of morbidity in neonates, complex congenital heart disease, increased preoperative severity of illness and with prolonged bypass. Patients with any morbidity had a 6-month survival of 81.5% compared with 99.1% with no morbidity. Patients with any morbidity scored 5.2 points lower on their total quality of life score at 6 weeks, but this difference had narrowed by 6 months. Morbidity led to fewer days at home by 6 months and higher costs. Extracorporeal life support patients had the lowest days at home (median: 43 days out of 183 days) and highest costs (£71,051 higher than no morbidity).

Limitations

Monitoring of morbidity is more complex than mortality, and hence this requires resources and clinician buy-in.

Conclusions

Evaluation of postoperative morbidity provides important information over and above 30-day survival and should become the focus of audit and quality improvement.

Future work

National audit of morbidities has been initiated. Further research is needed to understand the implications of feeding problems and renal failure and to evaluate the brief developmental assessment.

Funding

This project was funded by the NIHR Health Services and Delivery Research programme and will be published in full in Health Services and Delivery Research; Vol. 8, No. 30. See the NIHR Journals Library website for further project information.

Evolution of care pathways for babies with hypoplastic left heart syndrome: integrating mechanistic and clinical process investigation, standardization, and collaborative study

Since initial descriptions of staged palliation for hypoplastic left heart syndrome (HLHS) in the 1980’s, much has been learned about the pathophysiology of the single ventricle circulation. New therapies that leverage systems biology and clinical derivatives have been developed. While in-hospital mortality and morbidity for babies with HLHS have continued to improve, there remains a long (and daresay winding) road ahead to achieve ideal outcomes. Important variation in even these abbreviated in-hospital metrics persists among institutions and currently utilized prediction models explain only a small amount of this variation. Moreover, long-term survival and neurodevelopmental health for patients with HLHS are infrequently reported and remain suboptimal despite improved in-hospital outcomes. This focused review will describe the evolution of national outcomes for HLHS over time and the potential factors motivating improved time-related mortality. Emerging modifiable risk-factors that hold promise in terms of moving the needle for long-term success, including social determinants of health and the delineation of genetic profiles, will be discussed. Specifically, this review will integrate contemporary data based on the first murine HLHS models that suggest a genetically elicited modular phenotype with environmental factors known to impact the initial durability of surgical therapies. A comprehensive approach to the management of HLHS, which leverages both proactive transplantation and hybrid palliation, in addition to traditional Norwood palliation, will be emphasized to extend and match management to the complete spectrum of patient risk-profiles. Finally, we will explore the critical role that national collaboratives and quality reporting initiatives have played in improving outcomes and shifting the focus to more meaningful long-term survival and neurodevelopment.

Transplantation-free survival after Norwood surgery for hypoplastic left heart syndrome with aortic atresia: A Swedish national cohort study

BACKGROUND

Norwood surgery has been available in Sweden since 1993. In this national cohort study, we analysed transplantation-free survival after Norwood surgery for hypoplastic left heart syndrome with aortic atresia.

METHODS

Patients were identified from the complete national cohort of live-born with hypoplastic left heart syndrome/aortic atresia 1993-2010. Analysis of survival after surgery was performed using Cox proportional hazards models for the total cohort and for birth period and gender separately. Thirty-day mortality and inter-stage mortality were analysed. Patients were followed until September 2016.

RESULTS

The 1993-2010 cohort consisted of 208 live-born infants. Norwood surgery was performed in 121/208 (58%). The overall transplantation-free survival was 61/121 (50%). The survival was higher in the late period (10-year survival 63%) than in the early period (10-year survival 40%) (p = 0.010) and lower for female (10-year survival 34%) than for male patients (10-year survival 59%) (p = 0.002). Inter-stage mortality between stages I and II decreased from 23 to 8% (p = 0.008). For male patients, low birthweight in relation to gestational age was a factor associated with poor outcome.

CONCLUSION

The survival after Norwood surgery for hypoplastic left heart syndrome/aortic atresia improved by era of surgery, mainly explained by improved survival between stages I and II. Female gender was a significant risk factor for death or transplantation. For male patients, there was an increased risk of death when birthweight was lower than expected in relation to gestational age.

An Overview of Contemporary Outcomes in Fetal Cardiac Intervention: A Case for High-Volume Superspecialization?

Fetal cardiac interventions (FCI) offer the opportunity to rescue a fetus at risk of intrauterine death, or more ambitiously to alter disease progression. Most of these fetuses require multiple additional postnatal procedures, and it is difficult to disentangle the effect of the fetal procedure from that of the postnatal management sequence. The true clinical impact of FCI may only be discernible in large-volume institutions that can commit to a standardized postnatal approach and have sufficient case volume to overcome their FCI learning curve.

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.

The Evolution of Therapeutic Strategies: Niche Apportionment for Hybrid Palliation

Hybrid palliation, the concept to stabilize univentricular circulation with bilateral pulmonary artery banding and maintenance of ductal patency, has significantly widened the therapeutic spectrum for patients with single-ventricle malformations or borderline hypoplasia. The concept has already been a part of early attempts to improve outcome in hypoplastic left heart syndrome but has not attracted much attention initially. Technical refinement and expertise have led to results that ultimately allowed the palliative strategy to gain traction and to be selectively adopted. By now, we have gained almost 2 decades of experience, and as much as hybrid palliation has changed our approach to single-ventricle management, new strategies and indications have been formed by this experience. We therefore review concepts and patterns of use of hybrid palliation as well as benefits and challenges of the respective pathways to highlight the current status of the hybrid procedure.