Fig 11. Coupling between re-entry and SCRE.

A–SR-Ca²⁺ concentration (i) and V_m (ii) associated with sustained re-entry followed by self-termination (at around 13 s), simulations without SCRE (purple) and with the General Dynamic SRF model with two different thresholds (orange, 1.125 mM; blue, 1.0 mM). B–Temporal snapshots of voltage in the 2D sheet associated with the traces shown in A, showing self-termination (i) and the emergence of delayed (ii, corresponding to the orange traces in A) and rapid (iii, corresponding to the blue trace in A) focal excitations. C–Examples of non-localised focal excitations emerging in the 2D sheet (i) and 3D whole atria models (ii). Baseline General Dynamic SRF parameters, corresponding to panel A(orange)/Bii: CaSR_threshold = 1.25 mM; CaSR_max = 1.525 mM; CaSR_{P_range} = 0.05 mM; t_i,Sep^min = 300 ms; t_i,Sep^max = 870 ms; t_i,width^min = 200 ms; t_i,width^max = 1000 ms; MD^min = 150ms; MD^max = 600 ms; λ_width^min = 70 ms; λ_width^max = 300 ms; H_width = 2.5. Parameter differences for panel A(blue)/Biii: CaSR_threshold = 1.00 mM; CaSR_max = 1.2 mM; t_i,Sep^min = 30 ms; MD^min = 50ms; λ_width^min = 20 ms. For panel Ci: MD^min = 160ms; λ_width^min = 75 ms; λ_width^max = 300 ms. For panel Cii: CaSR_threshold = 0.9 mM; CaSR_max = 1.3 mM; t_i,Sep^min = 30 ms; t_i,width^min = 20 ms; MD^min = 80ms; MD^max = 800 ms; λ_width^min = 20 ms.