Figure 1.

The dyadic model predicted reduced I_LCC magnitude/kinetics during the CHF AP, and SR content-dependent effects on Ca²⁺ release synchrony. (A) Representative SHAM and CHF APs (inset of left panel) were incorporated in the computation model of both a large (left panels) and small dyad (right panels). A greater number of open LCCs was predicted during the CHF AP. At normal SR content, decreased driving force for Ca²⁺ entry during the CHF AP reduced I_LCC magnitude and kinetics (B), and resulted in more variable timing (dyssynchrony) of RyR openings (C). Increasing RyR Ca²⁺ sensitivity (orange lines) to model the effects of increased SR Ca²⁺ content during the CHF AP (observed experimentally) predicted decreased variability in the timing of RyR openings.