Global cardiac excitability via alteration of cardiomyocyte transmembrane potential

Global cardiac excitability via alteration of cardiomyocyte transmembrane potential refers to the integrated electrical state of the heart, determined by the electrochemical gradients and the selective permeability of the sarcolemma to ions like sodium, potassium, and calcium (StatPearls, 2023). This phenomenon is not a discrete molecular target, such as a single receptor or enzyme, but rather a complex physiological process involving the coordinated activity of multiple ion channels and transporters (PubMed, PMID: 19103161). The transmembrane potential is critical for the generation and propagation of action potentials, which are the electrical signals that trigger synchronized myocardial contraction (NIH, 2022). Pharmacological modulation of this process is a cornerstone of antiarrhythmic therapy, where drugs interact with specific channels to stabilize the membrane potential or prolong refractory periods (NCBI Bookshelf, NBK538143). However, because this process involves the global electrical balance of the heart, therapeutic interventions carry significant risks of pro-arrhythmia if the balance is disrupted (PubMed, PMID: 25660923). Consequently, while it is a vital physiological parameter, it is considered a mechanism of action or a physiological effect rather than a specific drug target.

Other names

Cardiac excitabilityTransmembrane potential modulationMyocardial excitabilityCardiac electrophysiological state

Modulation of ion channel conductance (sodium, potassium, calcium) to shift the resting membrane potential or alter action potential duration and refractory periods.