Introduction
Congenital heart disease (CHD) affects approximately 5600 live-born children annually in England and Wales.1 Each year, 7000–8000 paediatric cardiac procedures are undertaken in the UK, 58%–60% of them in children under 1 year old (infants),2 with an average 30-day mortality rate of 2%,2 although the risk is higher for complex CHD.3 The risk of mortality for an individual child is greatest during infancy.1 There is a substantial risk of postdischarge mortality and unexpected critical illness, especially in medically complex infants.4 Studies from the USA indicate that postdischarge mortalities can be mitigated by increased healthcare surveillance.5 In the USA, risk factors for late death in infants with complex CHD include residence in more deprived neighbourhoods,6 Hispanic compared with white ethnicity7 and black compared with white ethnicity.8 Poorer outcomes based on social factors have been attributed to unequal access to healthcare.6 8
Although the UK National Health Service (NHS) provides care that is universal and free at the point of access, services were affected by the COVID-19 pandemic. During pandemic restrictions, some UK-based families and patients affected by CHD reported delays and cancellations in healthcare appointments in an online forum study.9 The number of elective paediatric cardiac surgeries undertaken was reduced, during pandemic restrictions, although urgent surgeries were maintained.10 The parents of young children were in general, much less likely than usual to access emergency care.11 We, therefore, aimed to explore the impact of the COVID-19 pandemic on the timing of the expected operative treatment pathway and to evaluate any increases in mortality or time spent in hospital during infancy for children with complex CHD. In secondary analyses, we aimed to investigate whether social covariates that have been linked vulnerability of infants with CHD (sex,12 ethnicity7 8 and residential area deprivation6) were associated with the study outcomes during the pandemic.