Cardiac monitoring

Cardiac monitoring
Holter monitor.

Cardiac monitoring generally refers to continuous or intermittent monitoring of heart activity to assess a patient's condition relative to their cardiac rhythm. Cardiac monitoring is usually carried out using electrocardiography, which is a noninvasive process that records the heart's electrical activity and displays it in an electrocardiogram.^[1] It is different from hemodynamic monitoring, which monitors the pressure and flow of blood within the cardiovascular system. The two may be performed simultaneously on critical heart patients. Cardiac monitoring for ambulatory patients (those well enough to walk around) is known as ambulatory electrocardiography and uses a small, wearable device, such as a Holter monitor, wireless ambulatory ECG, or an implantable loop recorder. Data from a cardiac monitor can be transmitted to a distant monitoring station in a process known as telemetry or biotelemetry.

Cardiac monitoring in an emergency department setting focuses primarily on the monitoring of arrhythmia, myocardial infarction, and QT interval monitoring.^[2] It is categorized into one of three classes using a rating system developed by the American College of Cardiology Emergency Cardiac Care Committee:

Class I: Cardiac monitoring is indicated in all or most patients.

Class II: Cardiac monitoring may be beneficial, but it is not essential.

Class III: Cardiac monitoring is not indicated because the patient's serious event risk is low. Monitoring will not have therapeutic benefit.^[3]