Long-term outcomes in Tetralogy of Fallot: from the australian national congenital heart disease registry
J Chami, C Nicholson, G Strange, D Baker, R Cordina, D S CelermajerAbstract
Background
Survival in Tetralogy of Fallot (TOF) has improved markedly over recent decades, resulting in an ever-growing population of children and adults requiring lifelong specialist care. Nevertheless, national, whole-population descriptions of contemporary TOF outcomes, including continuity of specialist follow-up, remain limited.
Purpose
To describe long-term mortality, hospitalisations, cardiac interventions and follow-up for Australians born with TOF from 1985 to 2023.
Methods
We undertook a retrospective national linkage study using the Australian National Congenital Heart Disease Registry, identifying all patients born with TOF between 1 January 1985 and 31 December 2023 (n = 3713). Linkage with the National Death Index ensured complete ascertainment of mortality and causes of death. Administrative linkages for hospital admissions and Medicare Benefits Schedule outpatient specialist attendance claims were available from 1 January 2010 to 31 December 2020. Primary outcomes were mortality, analysed using Kaplan–Meier methods and multivariable Cox proportional hazards models, and hospitalisation rates for cardiac interventions/reinterventions and common complications (arrhythmia, heart failure, infective endocarditis and stroke), reported per 100 person-years. Continuity of care was assessed using the weighted mean percentage of follow-up time spent more than 24 months since the most recent outpatient cardiology visit.
Results
Of 3713 TOF patients (57% male), there were 241 deaths over 72169 person-years (0.33 per 100 person-years), the majority due to cardiovascular causes. Estimated survival at ages 5, 16, 30 and 38 years was 95.5%, 94.6%, 92.0%, and 88.6% respectively. The presence of chromosomal abnormalities was independently associated with higher mortality after adjustment for covariates, whereas rurality, sex and birth year were not. Between 2010 and 2020, 75% of surviving TOF patients had at least one hospital admission. In total, there were 16392 admissions (52 per 100 person-years) with 83641 total bed-days including 10730 days in intensive care. Admission rates for cardiac intervention and reintervention were 8.03 and 4.56 per 100 person-years respectively, with higher rates in younger age groups. Admission rates per 100 person-years were 2.1 for arrhythmia, 0.64 for heart failure, 0.37 for infective endocarditis and 0.096 for stroke. Adults spent more follow-up time outside care than children (51% vs 38%, p < 0.001), with no difference by rurality.
Conclusions
This study represents the largest lifespan-wide TOF cohort reported to date. Morbidity and health-service use were substantial, and continuity of care was suboptimal, especially in adulthood.Figure 1.Overall Kaplan–Meier Survival CurveFigure 2.Primary Causes of Death in TOF