Fetal heart modelling based on a pressure-volume relationship

Area of Science:

• Biomedical Engineering
• Cardiovascular Physiology
• Fetal Medicine

Background:

• Current fetal cardiovascular assessment relies on non-invasive methods like Doppler echography.
• Resistance indices from Doppler echography offer limited physiological insight into fetal circulation, particularly in distal territories such as the placenta and brain.

Purpose of the Study:

• To develop an enhanced numerical model of the human fetal heart.
• To improve the understanding of human fetal hemodynamics beyond current limitations.

Main Methods:

• A numerical model of the fetal heart was created using a hydraulic-electric analogy.
• The model hypothesizes parallel functioning of right and left ventricles with analogous elastance properties, equivalent to a single ventricle ejecting 7 ml.
• Model characterization involved determining four key parameters: maximum contractility (Emax), reference volume (Vo), and volume (kv) and pressure (Po) constants.

Main Results:

• The model's validation involved analyzing preload and afterload variations on fetal heart work.
• Numerical results were compared against existing literature and measured data, demonstrating model accuracy.
• The model successfully simulates fetal heart behavior under varying physiological conditions.

Conclusions:

• The developed numerical model represents a significant advancement in understanding fetal hemodynamics.
• This model serves as the foundational step towards a comprehensive model of the entire human fetal cardiovascular system.
• It offers a more detailed physiological representation compared to traditional resistance indices.