Prevalence and characterization of tetralogy of Fallot: a comprehensive study

Introduction: Tetralogy of Fallot (TOF) is a congenital heart defect (CHD) with a global prevalence of 3.56 cases per 10,000 live births (LBs), according to Liu et.al in 2019.Objective: This study aimed to determine the prevalence of and describe TOF cases in Bogot, Colombia from 2015 to 2021.Method: A retrospective cross-sectional study, based on data obtained from the Public Health Surveillance System database.Birth defects were classified according to the International Classification of Diseases (ICD-10), and cases were defined as all LBs with TOF, with a birth weight over 500 grams.Results: The estimated prevalence of TOF was 2.21 cases (confidence interval [CI] 1.85-2.61)per 10,000 LBs, with a total of 137 cases.The maximum prevalence was found in 2017, with 3.15 (CI 2.11-4.53),and the lowest prevalence in 2015, with 1.26 (CI 0.67-2.18)per 10,000 LBs.The mean birth weight was 2,575.9g (standard deviation [SD] 660.5), and the average gestational age at birth was 35.85 weeks (SD 3.95).The average maternal age was 29.1 years (SD 7.05).The mortality rate was estimated at 17.51%.Regarding health insurance, 10.95% of cases did not have insurance.Down syndrome and Edwards syndrome were found in nine and three cases, respectively.Conclusions: The prevalence of TOF in our city was lower than that reported in current global estimates.Nonetheless, there was an increase with regard to previous local data.This change in prevalence trends may be attributed to improvements in surveillance programs.