A closed-loop model of the canine cardiovascular system that includes ventricular interaction

Area of Science:

• Cardiovascular Physiology
• Computational Biology
• Biomedical Engineering

Background:

• Ventricular interaction and pericardial mechanics significantly influence hemodynamics.
• Previous models often studied these effects under isolated heart conditions.
• A comprehensive model is needed to assess these interactions within a closed-loop circulatory system.

Purpose of the Study:

• To develop and validate a closed-loop cardiopulmonary circulation model.
• To investigate the effects of ventricular interaction and pericardial mechanics on hemodynamics.
• To create a virtual testbed for predicting the impact of diseases and interventions.

Main Methods:

• Developed a closed-loop model incorporating interacting ventricles, atria, pericardium, and vascular loads.
• Employed a nonlinear least-squares parameter identification (Levenberg-Marquardt algorithm) and sensitivity analysis.
• Utilized dog cardiac pressure data from open-chest experiments for model parameter estimation.

Main Results:

• The model accurately simulates hemodynamics under normal and altered physiological conditions.
• Demonstrated the capability to study direct and series ventricular interactions and pericardial effects.
• Successfully predicted the impact of parameter alterations on steady-state hemodynamic performance.

Conclusions:

• The developed closed-loop model, integrated with the CardioPV software, provides a robust platform for cardiovascular research.
• It enables the assessment of global hemodynamic effects from localized alterations.
• Facilitates data-driven parameter estimation and online output visualization for enhanced understanding.