Holter and Event Monitoring | Tampa General Hospital

Holter and Event Monitoring 

Holter and event monitoring are similar to a standard electrocardiogram (EKG), a relatively simple diagnostic test used to monitor the heart’s electrical activity. However, unlike a large EKG machine, which records the heartbeat for only a few seconds during an in-office test, Holter and event monitors are small, portable devices that can be worn by a patient during normal activities to record his or her heartbeat over an extended period of time. 

Conditions Diagnosed 

A physician may suggest Holter or event monitoring to: 

  • Diagnose a heart rhythm problem (arrhythmia) in which the heart beats too fast, too slow or irregularly 
  • Detect silent (asymptomatic) myocardial ischemia, which occurs when the heart muscle does not receive a sufficient amount of oxygen-rich blood 
  • Evaluate the effectiveness of a treatment plan for arrhythmia or silent myocardial ischemia 

Procedure Details 

Most Holter and event monitors have electrodes, which are adhesive patches placed on the patient’s chest and connected to the recording device via wires. 

Holter Monitoring 

A Holter monitor records the heart’s electrical activity during the entire time the patient is wearing it, which is usually 24-48 hours. This may be a good option for a patient who recently began experiencing symptoms of cardiac irregularity. 

Cardiac Event Monitoring 

Typically worn for 30 days, a cardiac event monitor may be considered for a patient whose symptoms occur infrequently. When a patient experiences a cardiac abnormality, he or she will press a button to activate the device so that it will begin recording. Some devices have an auto-capture feature that automatically begins recording when a cardiac abnormality is detected. 

What to Expect 

There are no significant risks associated with Holter and event monitoring. Some patients experience minor skin irritation where the sticky electrodes are placed. Because the recording device can be damaged by water, a patient cannot shower, bathe or swim while wearing a Holter or event monitor. 


Holter and event monitors can record how fast the heart is beating, determine if the heartbeat is steady or irregular and even detect the strength and timing of electrical impulses as they pass through the heart. Some arrhythmias occur only during certain activities, such as exercise or sleep; as compared to a standard EKG, Holter and event monitoring are more likely to detect these problems. 

Tampa General Hospital’s Heart & Vascular Institute is proud to offer a comprehensive range of diagnostic cardiology services, including Holter and event monitoring.