Advances in surgical techniques and post-operative management of children with CHD have significantly lowered mortality rates. Unplanned cardiac interventions are a significant complication with implications on morbidity and mortality.

We conducted a single-centre retrospective case–control study for patients (<18 years) undergoing cardiac surgery for repair of Tetralogy of Fallot between January 2009 and December 2019. Data included patient characteristics, operative variables and outcomes. This study aimed to assess the incidence and risk factors for reintervention of Tetralogy of Fallot after cardiac surgery. The secondary outcome was to examine the incidence of long-term morbidity and mortality in those who underwent unplanned reinterventions.

During the study period 29 patients (6.8%) underwent unplanned reintervention, and were matched to 58 patients by age, weight and sex. Median age was 146 days, and median weight was 5.8 kg. Operative mortality was 7%, and 1-year survival was 86% for the entire cohort (cases and controls). Hispanic patients were more likely to have reinterventions (p = 0.04) in the unadjusted analysis, while Asian, Pacific Islander and Native American (p = 0.01) in the multi-variate analysis. Patients that underwent reintervention were more likely to have post-op arrhythmia, genetic syndromes and higher operative and 1-year mortality (p < 0.05).

Unplanned cardiac interventions following Tetralogy of Fallot repair are common, and associated with increased operative, and 1-year mortality. Race, genetic syndromes and post-operative arrhythmia are associated with increased odds of unplanned reinterventions. Future studies are needed to identify modifiable risk factors to minimise unplanned reinterventions.