Certified EKG Technician (CET) Practice Exam 2025 – Comprehensive Test Prep

The function of the ectopic pacemaker is primarily to initiate impulses outside of the sinoatrial (SA) node. The SA node is the heart's natural pacemaker, responsible for setting the rhythm of the heart's contractions. However, there are times when this normal conduction pathway is disrupted due to various conditions. In such cases, ectopic pacemakers can emerge, which are abnormal pacemaker sites in the heart that take over and generate electrical impulses, contributing to heartbeats.

This phenomenon occurs when the SA node is either not functioning properly or is overridden, allowing these ectopic areas—often located in the atria, ventricles, or the junction of the atria and ventricles—to generate impulses. This can lead to arrhythmias or irregular heart rhythms, as the impulses may not be well-coordinated, often leading to rapid heart rates or ineffective contractions.

In contrast, functions like synchronizing heart contractions or regulating blood flow through the heart relate to the coordinated activity of the heart's conduction system, which includes the proper functioning of the SA node and the atrioventricular (AV) node, rather than ectopic pacemaker activity. Additionally, while the heart rate may vary due to exercise, the ectopic pacemaker's role