Damage to the SA node If the SA node does not function, or the impulse generated in the SA node is blocked before it travels down the electrical conduction system, a group of cells further down the heart will become its pacemaker. This center is typically represented by cells inside the atrioventricular node (AV node), which is an area between the atria and ventricles, within the atrial septum. If the AV node also fails, Purkinje fibers are occasionally capable of acting as the default or "escape" pacemaker. The reason Purkinje cells do not normally control the heart rate is that they generate action potentials at a lower frequency than the AV or SA nodes. Artificial pacemakers
Cardiac pacemaker
Artificial cardiac pacemaker
Biological pacemaker
Artificial heart valve
Ventricular assist device
Antiarrhythmic agent
Transvenous pacing
Artificial heart