Diagnostic and interventional trends in tetralogy of fallot and transposition of the great arteries in a population-based study

The goal of this study was to analyze diagnostic and interventional trends in tetralogy of Fallot and transposition of the great arteries in Malta for individuals born during 1920-1994 and calculate birth prevalences. The design was population based, in the setting of a regional hospital providing exclusive diagnostic and follow-up services for the entire population of Malta. Data collection and analysis was retrospective and included comparison with earlier epidemiological studies. Patients included were all Maltese live births diagnosed as having tetralogy of Fallot (TF) and transposition of the great arteries (TGA) born by the end of 1994. There were 109 cases of TF and 30 cases of TGA (n = 30). A significant decline in age at diagnosis and age at surgery was found for both lesions (p < 0.0001), which was associated with a significant decline in perioperative mortality (p = 0.005). Underascertainment was present prior to 1980, however, more cases were diagnosed due to improvement of postmortem services in the early 1980s followed by improvement of clinical services with eventually exclusive premortem diagnosis. The birth prevalence of TGA was 0.31/1000 live births, well within the range described in previous studies, unlike tetralogy of Fallot, which has been found in excess in this population in an earlier study. TF and TGA, the two lesions which comprise the majority of cyanotic congenital heart disease presenting in infancy, have been diagnosed and have undergone intervention at progressively earlier ages over the period under study. This decline was associated with a declining perioperative mortality.