Volume 10 | Issue 10
ISSN (Print): 1759-1376
ISSN (Online): 2041-9457
The heartbeat is initiated by an intrinsic electrical system composed of modified myocytes. These myocytes are organised into a group of spontaneously discharging pacemaker cells, situated in the sinoatrial (SA) node, and a series of elongated conduction fibre cells, responsible for propagating electrical impulses throughout the heart (Levick, 2010). The SA node is situated close to the superior vena cava on the posterior wall of the right atrium.