Cardiac muscle cell excitability

Cardiac muscle cell excitability refers to the ability of cardiac myocytes to respond to electrical stimuli by generating and propagating action potentials. This is a fundamental physiological property rather than a single molecular entity. Excitability depends on the coordinated activity of multiple transmembrane ion channels—including voltage-gated sodium, potassium, and calcium channels—which together shape the cardiac action potential. The process enables rapid depolarization and repolarization cycles necessary for synchronized contraction and relaxation of heart muscle[1][3][6]. Alterations in cellular excitability can lead to serious conditions such as arrhythmias or sudden cardiac death[2][7]. However, "cardiac muscle cell excitability" is not itself a therapeutic target but rather an emergent property resulting from the function—and dysfunction—of many individual molecular targets. Note: There is something incorrect about using "cardiac muscle cell excitability" as a drug target name. It describes an emergent electrophysiological characteristic rather than any single protein or receptor that could be directly targeted by drugs. For structured data purposes it should be replaced with one or more specific molecules—such as “Voltage-gated sodium channel subunit alpha Nav1.5” (*SCN5A*), “L-type calcium channel”, etc.—that underlie this physiological phenomenon[6].

Other names

Excitability of cardiac myocyteCardiac myocyte excitabilityMyocardial cell excitability