Introduction
Prenatal screening for congenital heart defects (CHD) reduces the mortality and morbidity of newborns (1)(2), but also helps to improve their neuro-developmental outcome (3)(4). However, there is room for improvement in this screening which varies considerably, not only between countries, but also between regions within countries (5)(6)(7).
According to Sklansky et al. , the main reason for this shortcoming is that effective foetal echocardiography requires not only different images specific to the individual, as recommended by the national (CNEOF) and international (ISUOG, AUIM) learned societies, but also, and above all, good quality, informative images (8). The quality of cardiac screening examinations is the cornerstone to improve the detection rate of CHD in a low-risk population (9).
For more than 20 years, it has been recognized that screening for CHD can be improved by adding outflow tracts to the images of the four chamber view, with reported screening rates of 80% compared to 50% previously (10). After the CNEOF updated factors to be included in ultrasound screening in France in 2016, examination of the left ventricular outflow tract (LVOT) was added to ultrasound examination conducted in the second and third trimester of pregnancy.
The use of quality criteria for outflow tract scans addresses the need to minimize the source of misevaluation and/or misinterpretation of images of foetal heart anatomy, for this area of interest (8).
The objective of this study was, on the one hand, to carry out an audit of past and current practices and, on the other, to study possible modifications following the introduction of quality criteria for LVOT examination in the field of foetal echocardiography screening. It is crucial to rely on precise anatomical features which should be investigated and identified on such images.