Fig. 1

Schematic representation of ventricular electromechanical modeling. Left side is electrical components and right side is mechanical components. The electrical components consist of cell membrane Cm as a capacitive component connected in parallel with variable resistances and batteries, representing the ionic currents and pumps. \(I_{\rm{Na}}\) is rapid inward Na⁺ current, \(I_{\rm{Na,b}}\) \(I_{\rm{Ca,b}}\) is background Na⁺ and Ca²⁺ current, \(I_{\rm{Ca,L}}\) is L-type Ca²⁺ current, \(I_{\rm{Kr}}\) is rapid delayed rectifier \({\rm{K^+}}\) current, \(I_{\rm{Ks}}\) is slow delayed rectifier \({\rm{K^+}}\) current, \(I_{\rm{K1}}\) is inward rectifier \({\rm{K^+}}\) current, \(I_{\rm{Na,Ca}}\) is Na⁺–Ca²⁺ exchanger current, \(I_{\rm{p,Ca}}\) is Ca²⁺ pump current, \(I_{\rm{Na,K}}\) is Na⁺–\({\rm{K^+}}\) pump current, \(I_{\rm{to}}\) is transient outward \({\rm{K^+}}\) current, \(I_{\rm{p,K}}\) is \({\rm{K^+}}\) pump current, \(I_{leak}\) is Ca²⁺ released current from SR, \(I_{up}\) is SR Ca²⁺ uptake current, \(I_{rel}\) is Ca²⁺ induced-Ca²⁺ released current, \(E_{\rm{Na}}\) is Na⁺ pump, \(E_{\rm{Ca}}\) is Ca²⁺ pump, and \(E_K\) is \({\rm{K^+}}\) pump. The mechanical component represented by the myofilament model. \(N_{xB}\) and \(P_{xB}\) are non-permissive and permissive confirmation of regulatory proteins, \(XB_{PreR}\) and \(XB_{PostR}\) are pre-rotated and post-rotated states of myosin head-binding