Simulating Stenotic Conditions of the Coronary Artery in a Lumped Parameter Model of the Cardiovascular System

Area of Science:

• Cardiovascular Physiology
• Biomedical Engineering
• Computational Modeling

Background:

• Coronary blood flow (CBF) is crucial for heart function, normally maintained at 4% of cardiac output (CO).
• Coronary artery disease (CAD) can significantly alter CBF regulation.
• Accurate estimation of coronary microvascular resistance is vital for diagnosing and managing CAD.

Purpose of the Study:

• To develop and validate a pulsatile lumped parameter (LP) model of the cardiovascular system (CVS).
• To estimate coronary microvascular resistance using non-linear least square optimization.
• To simulate the effects of varying coronary epicardial resistance on microvascular resistance.

Main Methods:

• A sixth-order pulsatile LP model of the CVS was developed.
• The model incorporates a third-order representation of the coronary vascular bed.
• Non-linear least square optimization was used with average CBF and arterial blood pressure (ABP) waveforms.

Main Results:

• The model successfully achieved phasic coronary flow simulation.
• Realistic coronary microvascular resistance behavior was emulated under varying degrees of stenosis.
• The model provides a method for estimating coronary microvascular resistance from non-invasive data.

Conclusions:

• The developed LP model offers a valuable tool for assessing coronary microvascular function.
• This approach can aid in the early detection and understanding of coronary artery disease.
• The model's ability to emulate stenosis effects enhances its clinical relevance.