Assessment of Diastolic Function During the Transitional Period and Infancy Using Serial Echocardiography

A Longitudinal Observational Assessment of Diastolic Function During the Transitional Period and Infancy Using Serial Echocardiography in Neonates Born at 35 Weeks Gestation or Above

The goal of this single-centre longitudinal observational study is to create reference values for diastolic function parameters in neonates born at 35 weeks' gestation or above, and to assess the influence of pre-defined antenatal, intrapartum, maternal, and neonatal factors on cardiac function.

The main question it aims to answer are:

• What are the normal reference ranges for parameters of diastolic cardiac function in neonates?
• How are these influenced by maternal, intrapartum and neonatal factors?
• Do the diastolic changes noted during the first two days of life persist into infancy?

Participants will have four echocardiographic assessments in total:

• Two during the first 48 hours of life (prior to discharge home)
• Two during infancy (as an outpatient)

Participants will have their first echo to assess diastolic function, using both conventional and novel echocardiographic measure, within the first 6 to 18 hours of life approximately (Day 1 scan) and this will be repeated at 30 to 42 hours of life (Day 2 scan). Both scans will involve a comprehensive structural assessment to confirm normal anatomy.

All participants will be invited to return for follow-up targeted echocardiography assessments to evaluate function at approximately 6 - 9 months (Scan 3) and at approximately 12 - 18 months of life (Scan 4). At each of these visits, their weight, height, any interim hospital admissions, serious illnesses or medical issues and medications will be documented using a structured checklist format.

Inclusion Criteria:

• Birth at 35 weeks gestation or above
• Informed consent obtained

Exclusion Criteria:

• Any apparent congenital anomalies
• Any known chromosomal abnormalities (except Trisomy 21)
• Any known congenital structural heart disease (except patent ductus arteriosus, atrial septal defect, patent foramen ovale or ventricular septal defect)