Phase resetting in human stem cell derived cardiomyocytes explains complex cardiac arrhythmias
Fig 3
Dynamical regimes observed in experimental and clinical data, explained by bifurcation analysis of mathematical models.
(A) Bifurcation diagram of the periodically-forced oscillator model (Eq. 1) using the experimentally fitted PRC from Fig 1B. Blue dots mark experimental data. The shaded region indicates the range of values observed in the patient data. (B) Cobweb plots for Eq. 1 at selected values of
studied in experiments. The return map is shown in red; model iterations after transients are shown in black; experimental data are overlaid in blue. The identity line, along which
, is shown as a dashed line. (C) Bifurcation diagram of the modulated parasystole model (Eq. 2), using the same experimentally fitted PRC, plotted over the range of
values observed in the patient record. Vertical blue lines indicate specific
values corresponding to the clinical segments shown in Fig 2C. (D) Corresponding cobweb plots for Eq. 2 for each
value. The three regions above the graph indicate different contexts for the sinus beat depending on its phase. V(N), blocked sinus beat preceded by an ectopic beat; (V)N, sinus beat preceded by a blocked ectopic beat; N, single sinus beat. S8 Fig provides an explanation how the cobweb plots in panels B and D relate to the entrainment patterns seen in Figs 1 and 2.