Impact of a Standardised Fetal Cardiac Screening Programme on Antenatal Detection Rates of Transposition of the Great Arteries

Abstract

BACKGROUND: Dextro-transposition of the great arteries (d-TGA) can be difficult to diagnose antenatally. Standardised cardiac screening protocols may improve detection rates. AIMS: The objective of this study was to examine rates of antenatal diagnosis of d-TGA in regional and metropolitan Brisbane over a 10-year period and assess if a targeted antenatal screening education programme had an impact on detection rates. MATERIALS AND METHODS: A retrospective cohort study was conducted. Data were collected for infants diagnosed with d-TGA in Queensland between January 2008 and December 2017. Infants were divided into two cohorts to assess antenatal detection rates in both regional and metropolitan areas Queensland pre- and post implementation of a targeted sonographer education programme between 2008 and 2011. RESULTS: A total of 126 infants were identified with a diagnosis of d-TGA. The overall antenatal detection rate was 63.5% across the 10-year study period. Prior to the educational intervention, the detection rate was 51% (2008-2011 n = 23/45), which increased significantly to 70% post educational intervention (2012-2017, n = 57/81) (p = 0.035). Regional Queensland (n = 60) detection rates increased from 44% to 63% (p = 0.192) and metropolitan (n = 66) detection rates increased from 60% to 76% (p = 0.24) post educational intervention. CONCLUSIONS: Rates of antenatal diagnosis of d-TGA in Queensland compare favourably with internationally published rates, although difficulty in consistently diagnosing this congenital heart defect remains. A targeted educational programme of sonographers performing antenatal screening, particularly in regional areas, appears to increase rates of prenatal diagnosis and improve outcomes.