Figure 9.

Emergence of H₂O₂-induced EADs is related to a shift in the time of NCX current reversal. The NCX RP for all EADs (asterisks) generated in the presence of ROS (PCL ≥ 2 s), including those with interventions such as RyR inhibition, lies within a narrow voltage range. Squares represent stable APs simulated in the presence of ROS either at a fast pacing rate (e.g., PCL ≤ 1 s) or at a slower pacing rate (e.g., PCL = 2 s). Note that at PCL = 2 s, both stable APs (green squares) and EADs (green asterisks) occur in the model output. For a PCL of 4 s, only four stable APs out of 50 simulated APs are predicted. Stable APs as a result of NCX inhibition at PCL = 2 s and PCL = 6 s are shown by green and blue triangles, respectively. To see this figure in color, go online.