Understanding Fetal Hemodynamics Using Cardiovascular Magnetic Resonance Imaging

Area of Science:

• Fetal Physiology
• Cardiovascular Imaging
• Medical Diagnostics

Background:

• Ultrasound is standard for fetal cardiac anatomy and function but limited in measuring blood flow and oxygenation.
• Invasive animal studies historically informed fetal circulation research but lack human specificity.
• Current ultrasound methods indirectly assess fetal cardiovascular health, necessitating advanced techniques.

Purpose of the Study:

• To investigate human fetal circulatory physiology using advanced cardiovascular magnetic resonance (CMR).
• To measure fetal blood flow, oxygen saturation, and hematocrit non-invasively.
• To correlate fetal cardiovascular function with development in conditions like congenital heart disease and placental insufficiency.

Main Methods:

• Utilized cardiovascular magnetic resonance (CMR) for non-invasive fetal circulatory assessment.
• Employed cine phase contrast MRI for blood flow quantification.
• Applied T1 and T2 mapping for blood oxygen saturation and hematocrit measurements.

Main Results:

• Successfully emulated classic fetal sheep experiments in humans using CMR.
• Enabled direct measurement of blood flow distribution and oxygen transport in the human fetus.
• Provided insights into abnormal fetal cardiovascular physiology and its impact on development.

Conclusions:

• CMR is a powerful tool for understanding normal and abnormal fetal circulatory physiology.
• This technique enhances the assessment of fetal well-being, particularly in congenital heart disease and placental insufficiency.
• CMR offers a non-invasive alternative to animal models for studying human fetal circulation.