cardiac atrium

cardiac conduction system The electrical conduction system that stimulates the heart to contract and pump blood. This system generates electrical impulses and conducts them throughout the muscle of the heart. Among the major elements in the cardiac conduction system are the sinoatrial node, the atrioventricular (AV) node, and the autonomic nervous system. See also atrioventricular node; autonomic nervous system; sinoatrial node.