Toward Quantification and Visualization of Active Stress Waves for Myocardial Biomechanical Function Assessment

Area of Science:

• Biomedical Engineering
• Computational Mechanics
• Cardiovascular Physiology

Background:

• Understanding myocardial active stress patterns is vital for assessing heart mechanical activity and function.
• Medical imaging techniques provide tissue displacement data, offering potential for non-invasive functional assessment.

Purpose of the Study:

• To develop and validate a 3D finite element (FE) formulation for reconstructing active stress distributions from displacement data.
• To demonstrate the model's capability in identifying simulated malfunctioning myocardial regions.

Main Methods:

• A 3D FE model with anisotropic fiber rotation was created to simulate myocardial tissue.
• A forward model generated deformation data from known active stresses.
• An inverse model reconstructed active stress from simulated displacement data, including noise analysis.

Main Results:

• The inverse model successfully reconstructed active stress distributions from simulated tissue deformation.
• The model demonstrated accuracy in estimating stress, even with added noise, indicating robustness.
• Simulated regions of limited contractility were identifiable through stress reconstruction.

Conclusions:

• The developed 3D FE application accurately estimates myocardial active stress from displacement data.
• This approach holds promise for non-invasive assessment of cardiac mechanical function and disease detection.