Active force generation in cardiac muscle cells: mathematical modeling and numerical simulation of the actin-myosin interaction

45/2019

Active force generation in cardiac muscle cells: mathematical modeling and numerical simulation of the actin-myosin interaction

Wednesday 20th November 2019

Regazzoni, F.; Dedè, L.; Quarteroni, A.

Cardiac in silico numerical simulations are based on mathematical models describing the physical processes involved in the heart function. In this review paper, we critically survey biophysical detailed mathematical models describing the subcellular mechanisms behind mechanical activation, that is the process by which the chemical energy of ATP (adenosine triphosphate) is transformed into mechanical work, thus making the muscle tissue contract. While presenting these models, that feature different levels of biophysical detail, we analyze the trade-off between the accuracy in the description of the subcellular mechanisms and the number of parameters that need to be estimated from experiments. Then, we focus on a generalized version of the classic Huxley model, that is able of reproducing the main experimental characterizations associated to the time scales typical of an heartbeat - such as the force-velocity relationship and the tissue stiffness in response to small steps - featuring only four independent parameters. Finally, we show how those parameters can be calibrated starting from macroscopic measurements available from experiments.