Proposed impact of SPOCs in health and disease. Potentially adaptive responses of SPOC include faster, more efficient contractile kinetics, enhanced mechanoelectrical feedback, and more coordinated contraction and relaxation across multiple cells or cardiac regions. Potential for SPOC dysregulation may occur under conditions that chronically affect cMyBP-C phosphorylation or that reduce cMyBP-C expression such as haploinsufficiency in HCM patients or proteolytic degradation of cMyBP-C during cardiac stress. Dysregulation may include negative impacts on contractile properties and efficiency; deranged mechanoelectrical feedback that disrupts Ca²⁺ signaling, or action potential characteristics (e.g., delayed afterdepolarizations, early afterdepolarizations, or slowed repolarization); and regional foci of hyper- or hypoexcitability. HF, heart failure. Figure created with BioRender.com.