Toronto Heart Centre
Services
Location
Patients
Our Doctors
Seminars
Contact Us
Diagnostic Tests in Cardiovascular Diseases

Back to Index

Figure 3Portable Holter recorder with solid-state memory

2. Ambulatory EKG (Holter) Monitoring

What is ambulatory EKG monitoring?

Ambulatory EKG Monitoring is commonly known as Holter monitoring. It is named after Holter, the engineer who developed the recording device that allows continuous monitoring of heart rhythm during normal daily activities in the early 1960s. Doctors often ordered this test to monitor patients who complained of palpitation or syncope (passing out).

How is it done?

The heart rhythm can be monitored for 24 hours to 48 hours at a time. Several small adhesive electrodes are placed on the surface of the chests during the hook up by the technician. The wires are connected to a small recorder device. The hook up takes approximately 20-30 minutes. The heart rhythm is recorded on a tape or the solid-state memory within the device. You will be fitted with a recorder that can be worn with a belt over the shoulder or attached to a waist belt. You will carry on with usual activities. You will have to record any symptom experienced by pressing the event button on the monitor. At the same time you will have to record in a symptom diary the timing and duration of the symptoms as well as the activities you are doing. The rhythm recorded is then correlated with the symptom reported.

How should I prepare for the test? Is there anything I should not do during the monitoring period?

It is useful to have a shower before hooking up the recorder and not to put any lotion or moisturizer onto the body. It is important not to get the electrodes, wires, or recorder wet. Do not swim or take a shower or bath while wearing the recorder. You should also avoid electric blankets as it may interfere with the electrical recording.

What should I do with the monitor at the end of the monitoring period?

At the end of the monitoring period you will return the recorder with the symptom diary to the lab. The information is then downloaded to a computer, analyzed by a trained technician and then interpreted by a physician. The report will be forwarded to your own physician who will review the results with you.

Are there any devices that can be used if the symptoms are infrequent?

There are devices, known as event monitors, which allow prolonged monitoring over period of weeks when symptoms are rare, and the information is stored in a solid state memory. Recording is activated retroactively when patient experienced any symptoms. There are new implantable devices that can be placed under the skin which allows even longer monitoring period for months at a time.