Heart rhythm

Heart rhythm refers to the coordinated sequence of electrical impulses and subsequent mechanical contractions of the heart muscle required to pump blood effectively throughout the body (StatPearls, NBK534864) [1]. It is a complex physiological process rather than a single molecular target, such as a receptor or enzyme. The rhythm is initiated by specialized pacemaker cells in the sinoatrial node and travels through a dedicated conduction system involving the atrioventricular node and Purkinje fibers (NIH, Heart Contraction and Blood Flow) [2]. Dysregulation of this process leads to cardiac arrhythmias, which are a major cause of morbidity and mortality worldwide. While heart rhythm itself is not a target, it is modulated by drugs that target specific ion channels (e.g., SCN5A, KCNH2) and G protein-coupled receptors (e.g., ADRB1) to restore normal sinus rhythm or control heart rate (PubMed, PMC4212347) [3].

Other names

Cardiac rhythmSinus rhythmHeart rateCardiac cycle

Pharmacological agents modulate heart rhythm by acting on specific molecular targets such as voltage-gated sodium (Nav1.5), potassium (hERG), and calcium channels (L-type), or by modulating autonomic input via beta-adrenergic and muscarinic receptors.