Figure 6.

Parameter sensitivity analysis of APD₆₀, Δ[Ca]_i, Δ[Ca]_SL, and Δ[Ca]_jct sensitivities toward 10% increases in Ca²⁺ and Na⁺ diffusion coefficients between subcellular compartments. Positive value indicates direct relationship between diffusion coefficient and output (e.g., increased diffusion coefficient between junctional cleft and sarcolemma prolongs APD₆₀) and negative sensitivity value indicates indirect relationship between parameter and output. Nimrod/E-Lenth plots (left column), PLS-bar plots (right column). Nimrod/E analysis produced similar qualitative results as PLS analysis.