Background: The epidemiological data on the incidence of congenital heart defects derive from retrospective registries based on birth discharge codes with methodological limits and different selection criteria. Our aim was to determine the actual incidence of congenital heart defects in the first year of life in a population of residents in a province of Tuscany, Italy.
Methods: This prospective study was conducted in 31 185 newborn residents in the province, enrolling a consecutive population throughout the first year of life and followed up at least for one year. The population cohort was controlled and merged with a retrospective research of the diagnostic codes derived from hospital discharge records of the region of Tuscany.
Results: A congenital heart disease was suspected in 10 167 newborns, 32.6% of all live births. Overall, 524 defects were diagnosed (5.2% of the exams), with an incidence at birth of 16.8/1000/year (M/F ratio 0.84). Isolated ventricular septal defects were 343 and 198 spontaneously closed within one year, therefore, the total number dropped to 326 with a one-year incidence of 10.35/1000/year. Besides ventricular septal defects, the most common defects were atrial septal defects (7.3%), followed by ductus arteriosus (4.2%), aortic coarctation (4%), pulmonary stenosis (3.3%) and tetralogy of Fallot (3.1%).
Conclusions: The one-year inclusion period and follow-up allowed us to exclude those defects whose hemodynamic significance is not clear at birth, or are spontaneously reversible within the first year of life. Nevertheless, with the inclusion of defects not evident at birth, congenital heart defects are still common.