EP09.47: Speckle tracking assessment of the fetal cardiac function in early labour: pathophysiology and association with adverse outcome

To investigate the relationship between speckle tracking echocardiography (STE) assessment of the fetal cardiac function, cardiotocography (CTG) and labour outcome in a cohort of singleton term pregnancies with normal CTG in the early stage of labour. Single-centre prospective study including a non-consecutive cohort of apparently low risk singleton pregnancies at 37+0 – 41+3 weeks. Two-dimensional ultrasound clips of the 4-chamber view of the fetal heart were collected in early labour and analysed by a single operator using TomTec GmbH. Offline STE analysis was performed and ventricular deformation rate was evaluated through the global radial strain (GRS) and myocardial and endocardial global longitudinal strain (MyoGLS and EndoGLS). Prerequisite was a normal CTG with baseline fetal heart rate (FHR) appropriate for the gestation. 164 cases were included, 14 (8.5%) were postnatally diagnosed as small for gestational age (SGA) while suspected intrapartum fetal compromise (IFC) leading to operative delivery (OD) was recorded in 13 (7.9%). A negative correlation between the right ventricle (RV) GRS and baseline FHR at recruitment (-0.145, p = 0.04) and birthweight percentile (-0.179, p = 0.02) was observed. Furthermore, higher left ventricle (LV) MyoGLS (-17.0 (-24.0 - -13.9) vs -14 (-26.0 - -5.0), p = 0.02) and higher RV MyoGLS (-16.0 (-22.0 – -12.0) vs -11 (-27.0 – -5.0), p < 0.01), EndoGLS (-18.0 (-24.0 – -10.3) vs -13.0 (-29.0 – -5.0), p < 0.01) and GRS (20.0 (6.0 – 34.0) vs 13.0 (0.0 – 46.0), p = 0.02) were recorded in cases submitted to OD due to suspected IFC. A higher RV MyoGLS and GRS and higher RV MyoGLS and EndoGLS were confirmed for cases of OD respectively within AGA and SGA subgroups. Within a population of singleton term pregnancies in early labour with normal CTG at recruitment an increased RV strain was observed with reducing birthweight and baseline FHR at recruitment. Furthermore, higher cardiac strain was shown in cases undergoing OD due to suspected IFC, irrespective of birthweight.