Abstract
Background
Tetralogy of Fallot (TF) is a rare disease characterized by the presence of 4 congenital heart defects (CHD). Objective: to describe the temporal trend and distribution of the TF in the Valencia Region (VR), in less than one year old, during the period 2007-2016.
Methods
Live births, stillbirths and termination of pregnancy due to fetal anomaly (TOPFA) between 2007-2016 with TF (code Q21.3 of the ICD10-BPA) were selected from the Congenital Anomalies (CA) population-based Registry of VR. The cases were confirmed through the review of clinical documentation. The prevalence of 10000 births with 95% confidence intervals (95%CI) was calculated for the period and for each year, and a descriptive analysis of sociodemographic and clinical variables was made.
Results
146 cases were identified (45.2% male, 31.5% female and 23.3% unknown), 89.0% were simple pregnancies and 54.8% were diagnosed prenatally. The overall prevalence of TF was 3.0/10000 births (95%CI: 2.5-3.5), being 2015 the year with the highest prevalence (4.3/10000 births) and 2011 with the lowest (1.8/10000 births). These changes were mainly due to the increase and decrease in the number of TOPFA respectively. 74.7% were live births, 22.6% TOPFA and 2.7% stillbirths. The prevalence in live births was 2.2/10000 births (95%CI: 1.8-2.6) and in TOPFA it was 0.7/10000 births (95%CI: 0.4-0.9), identifying an increasing trend during the period in the last one. 11.0% of live births died during the first year of life. 45.9% of the cases had another CA associated with the TF, being CHD in 52.7% of cases. 66.4% of the mothers were over 30 years of age, being the most frequent those between 30-34 years (30.1%).
Conclusions
The prevalence obtained in the VR was lower than that of EUROCAT 3.5/10000 births (95%CI: 3.3-3.6) during the same period. EUROCAT has also identified the difference between the prevalence in live births (2.9 (95%CI: 2.8-3.0)) and TOPFA (0.5 (95%CI: 0.5-0.6)), and the increasing trend in the last one.
Key messages
The prevalence of Tetralogy of Fallot obtained in the VR was lower than that of EUROCAT (European network of population-based registries for the epidemiologic surveillance of congenital anomalies). EUROCAT has also identified the difference between the prevalence of Tetralogy of Fallot in live births and termination of pregnancy due to fetal anomaly, and the increasing trend in the last one.
Tetralogy of Fallot in infants less than one year old in the Valencia Region (Spain)
