Figure 2.

Calcium cycling in the failing heart. The figure summarizes calcium cycling in the normal heart and how it changes in the failing heart. Proteins responsible for these alterations are highlighted in red (e.g., SERCA2a expression and molecular regulation; RyR2 aberrant gating), and the pathways to which they refer are described in the text. The importance of ATP in muscle contraction and relaxion is also depicted. On the right, a graphical abstract highlighting biogenesis and fusion-fission machinery in HF.