THE 30-YEAR OUTCOMES OF TETRALOGY OF FALLOT ACCORDING TO NATIVE ANATOMY AND GENETIC CONDITIONS

ABSTRACT Background The reported survival of tetralogy of Fallot (TOF) is >97%. Patients with pulmonary atresia and/or genetic conditions have worse outcomes, but long-term estimates of survival and morbidity for these TOF subgroup are scarce. The objective of this study was to describe the 30-year outcomes of TOF according to native anatomy and the coexistence of genetic conditions. Methods The TRIVIA study is a retrospective population-based cohort including all TOF subjects born between 1980 and 2015 in Quebec. We evaluated all-cause mortality with Cox proportional hazards regression, and cumulative mean number of cardiovascular interventions and unplanned hospitalizations using marginal means/rates models. We computed 30-year estimates of outcomes according to TOF types: classic TOF (cTOF) and TOF with pulmonary atresia (TOF-PA) and the presence of genetic conditions. Results We included 960 subjects. The median follow-up was 17 years (8–27). Nonsyndromic cTOF subjects had a 30-year survival of 95% and had undergone a mean of 2.8 interventions and 0.5 hospitalizations per subject. In comparison, TOF-PA subjects had a lower 30-year survival of 78% and underwent a mean of 8.1 interventions, with four-times as many hospitalizations. The presence of a genetic condition was associated with lower survival ( Conclusion The anatomical types and the presence of genetic conditions strongly influence the long-term outcomes of TOF. We provided robust 30-year estimates for key markers of prognosis that may be used to improve risk stratification and provide more informed counselling to families.