Non-invasive fetal electrocardiography, electrohysterography and speckle-tracking echocardiography in the second trimester: study protocol of a longitudinal prospective cohort study (BEATS-study)

Abstract

Background Worldwide, hypertensive disorders of pregnancy (HDP), fetal growth restriction (FGR) and preterm birth remain the leading causes of maternal and fetal pregnancy-related mortality and (long-term) morbidity. Fetal cardiac deformation changes can be the first sign of placental dysfunction, which is associated with HDP, FGR and preterm birth. In addition, preterm birth is likely associated with changes in electrical activity across the uterine muscle. Therefore, fetal cardiac function and uterine activity can be used for the early detection of these complications in pregnancy. Fetal cardiac function and uterine activity can be assessed by two-dimensional speckle-tracking echocardiography (2D-STE), non-invasive fetal electrocardiography (NI-fECG), and electrohysterography (EHG). This study aims to generate reference values for 2D-STE, NI-fECG and EHG parameters during the second trimester of pregnancy and to investigate the diagnostic potential of these parameters in the early detection of HDP, FGR and preterm birth. Methods In this longitudinal prospective cohort study, eligible women will be recruited from a tertiary care hospital and a primary midwifery practice. In total, 594 initially healthy pregnant women with an uncomplicated singleton pregnancy will be included. Recordings of NI-fECG and EHG will be made weekly from 22 until 28 weeks of gestation and 2D-STE measurements will be performed 4-weekly at 16, 20, 24 and 28 weeks gestational age. Retrospectively, pregnancies complicated with pregnancy-related diseases will be excluded from the cohort. Reference values for 2D-STE, NI-fECG and EHG parameters will be assessed in uncomplicated pregnancies. After, 2D-STE, NI-fCG and EHG parameters measured during gestation in complicated pregnancies will be compared with these reference values. Discussion This will be the a large prospective study investigating new technologies that could potentially have a high impact on antepartum fetal monitoring. Trial registration Registered on 26 March 2020 in the Dutch Trial Register (NL8769) via https://www.trialregister.nl/trials and registered on 21 October 2020 to the Central Committee on Research Involving Human Subjects (NL73607.015.20) via https://www.toetsingonline.nl/to/ccmo_search.nsf/Searchform?OpenForm.

Early Assessment of Cardiac Function by Echocardiography in Patients with Gestational Diabetes Mellitus

“…Short-term hyperglycemia during pregnancy has the same effect on heart function as non-pregnant people with a long history of diabetes. Researchers discovered that the GLS of radial strain differed in a retrospective analysis of 18 pregnant women with gestational diabetes in the second trimester of pregnancy [ 19 ]. Although the data in this section of the research are comparable to the findings in this study, it cannot be ruled out that these cardiovascular abnormalities are due to the small sample size, early gestational weeks at the time of examination, and brief exposure to hyperglycemia [ 20 ].…”

Feasibility and reliability of fetal two dimensional speckle tracking echocardiography at 16 weeks gestational age: A pilot study

“…This pilot study was conducted as part of a larger longitudinal prospective cohort study, the BEATS study. The study protocol for the BEATS study has been previously published [ 18 ]. The research was approved by the medical ethics committee of the Máxima Medical Center in Veldhoven, the Netherlands (NL73607.015.20).…”

“…The ultrasound system used for this study was the Philips Epiq W7 (Royal Philips N.V., Amsterdam, The Netherlands), which was equipped with a 9-MHz linear transducer. To minimize artifacts caused by maternal movements, pregnant women were instructed to hold their breath during the acquisition of the 4CV ultrasound clips [ 18 ]. Each 4CV ultrasound clip had a duration of 3 seconds and captured multiple cardiac cycles.…”

“…Additionally, it is suggested that the minimum sample size for a pilot study should be 9% of the intended sample size for the main trial [ 23 ]. Hence, a total of 50 participants, approximately 9% of the intended subjects in the main trial analysis, were included in this pilot study [ 18 ].…”