Computational Modelling of the Effect of Infarct Stiffness on Regional Myocardial Mechanics

Ventricular remodeling after myocardial infarction increases the rate of mortality and is highly associated with the extent of infarct transmurality. It is hypothesized that infarct stiffness alters regional mechanics and affects the likelihood of human ventricular remodeling. However, this is yet to be studied in detail. In this paper, we present simulations from an actively-contracting left ventricular model to investigate the effects of transmural infarct stiffness on myofiber regional mechanics. Results show that higher infarct stiffness reduces systolic stress at the infarct and border zones, minimizing infarct bulging but increasing the diastolic stress at the endocardial border zone. Determining a proper amount of infarct stiffness is required to achieve a balanced regional mechanics across the cardiac cycle that may be useful in therapy, such as myocardial hydrogel injection to adjust its stiffness and reduce stress to prevent ventricular remodeling.

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