Modelling of cardiac biventricular electromechanics with coronary blood flow to investigate the influence of coronary arterial motion on coronary haemodynamic.

BACKGROUND AND OBJECTIVE

Coronary flow is strongly influenced by the geometry and motion of coronary arteries, which change periodically in response to myocardial contraction throughout the cardiac cycle. However, a computational framework integrating cardiac biventricular electromechanics with dynamic coronary artery flow using a simplified, yet comprehensive mathematical approach remains underexplored. This study aims to develop a coupled 3D model of cardiac biventricular electromechanics and coronary circulation, enabling simulation of the interplay between cardiac electrical activity, mechanical function and coronary flow.

METHODS

A patient-specific biventricular electromechanical model encompasses the fibre orientation, electrophysiology, mechanical properties and an open-loop heart circulation is developed. The electromechanical model is simulated independently from the coronary circulation model. The model provides an input for the Navier-Stokes-based coronary flow model. A one-way coupling approach maps the biventricular motion to the coronary arteries, linking both components. To evaluate the influence of coronary arterial motion on coronary haemodynamic, simulations are performed for two scenarios: a moving and a non-moving (static) coronary artery model.

RESULTS

Cardiac-induced coronary motion alters the pressure, velocity and flow profiles. Non-moving coronary arteries produce stable counter-rotating Dean-like vortices due to steady flow dominated by centrifugal forces, while the moving arteries disrupt these vortices as arterial curvature changes disturb the flow. Coronary motion significantly affects the wall shear stress, highlighting the necessity of incorporating arterial dynamics to investigate atherosclerosis.

CONCLUSION

The integrated biventricular-coronary model emphasizes the significance of background cardiac motion in coronary haemodynamic. The model offers a foundation for exploring myocardial perfusion mechanisms in realistic physiological settings.