Figure 4.

Novel classification of Na_V1.5 (dys)function. The direct ionic function controls excitability by modification of membrane potential and initiation of AP. The indirect ionic function regulates calcium levels and downstream calcium signalling. The non-ionic function relies on the integrity of region-specific macromolecular complexes to control cell adhesion, cell–cell communication, signalling (other than calcium), myocardium architecture (extracellular matrix), and developmental aspects. AP, action potentials.