The Holter ECG is a device that records a patient’s electrocardiogram for 24 to 72 hours. It continuously records the cardiac electrical signal in order to diagnose a possible rhythmic disorder, a cardiac conduction problem, or to control the evolution of treatment or the proper functioning of a pacemaker.
More complete than a simple electrocardiogram, it takes place in a normal living environment. It is a painless examination that does not interfere with daily activities. Data processing software allows the analysis of the entire record and produces an automatic report. The cardiologist can then read it, view the recording, and write his conclusions.
What is an ECG holter?
The Holter ECG is a 24- to 72-hour electrocardiogram (ECG) recorder, which is the continuous electrical activity of the heart of a person who lives normally.
This recording is carried out with a portable, discreet and silent device, composed of a small box, also called a recording unit, worn slung over the shoulder or on the belt, weighing 150 to 250 grams, and connected by wires to electrodes placed on the skin of the chest. The latter is most often 5 in number and is glued to the skin with an adhesive.
The Holter ECG also consists of a processing terminal, i.e. data processing software, which is installed on the medical practitioner’s computer. It analyzes the entire record and produces an automatic report. The cardiologist can then read it, view the recording, and write his conclusions.
What is a Holter ECG used for?
The Holter ECG makes it possible to explore certain cardiac pathologies in a more complete way than the electrocardiogram. It makes it possible to carry out an examination intended to highlight a heart rhythm disorder.
It can also be used to monitor the effectiveness of treatments such as antiarrhythmic treatments or the proper functioning of a pacemaker, especially at night. It is mainly used for diagnostic purposes.
The analysis of the data makes it possible to know the frequency of heartbeats in real time over 24 hours, but also to visualize the abnormalities of the rhythm that may or may not correspond to a feeling of symptoms such as palpitations or chest pain, or be the cause of the discomfort, syncopation or even neurological symptoms.
The patient can press a button attached to the bracket as soon as he experiences a sensation such as palpitations or contractions in the chest. As a result, a clue will be transcribed on the recording so that the doctor or cardiologist can directly see the graph at that moment and make a solid diagnosis.
In order to capture a spaced occurrence anomaly, it is sometimes necessary to repeat the examination several times.
In more detail, the Holter ECG makes it possible to study:
- extrasystoles (irregular heartbeat), premature heartbeat;
- their type: auricular or ventricular ;
- their circumstances of occurrence: night or day, during exercise or at rest, isolated or grouped in more or less long series;
- heart rate: accelerated or slowed down with breaks;
- abnormal and rapid rhythms: atrial fibrillation, flutter, supraventricular tachycardia (Bouveret type), ventricular tachycardia;
- slowing of the heart rate: bradycardia, pause due to a cessation of the atria (sinus dysfunction), or a blockage of the impulse between the atria and ventricles (atrioventricular block), often causing discomfort or syncope.
How is an ECG Holter used?
More complete than a simple electrocardiogram, the examination performed with a Holter ECG takes place in a normal living environment whether the patient is active or resting. Painless and safe, it does not interfere with daily activities. During the check-in, the patient is asked to live normally during the 24 hours, work, and continue his usual treatment.
The Holter ECG is usually placed by a nurse. Very fast, the installation lasts about 15 minutes:
- after cleansing the skin, five self-adhesive electrodes are positioned on the patient’s chest and then covered with an adhesive strip;
- the device is connected to it and slipped into a pouch placed slung over the shoulder or on the belt;
- The patient receives a logbook to note the significant events of the day and their times of occurrence: getting up, going to bed, eating, taking medication, exertion as well as any symptoms that may be felt: palpitations, chest pain, shortness of breath, malaise, loss of consciousness.
Precautions to be taken
- it is useless to be fasting for the installation of an ECG Holter;
- wear low-cut clothing to avoid leaving the electrodes visible;
- for women: wear a bra without a metal frame or a bra;
- for men: perform a chest shave to optimize the quality of the recording;
- keep all mobile phones, tablets, MP3s, and computers away from the recorder;
- avoid wearing jewelry around your neck;
- avoid wearing wool or synthetic underwear;
- favor cotton clothing;
- if an electrode or cable comes loose, put it back on as soon as possible;
- avoid scratching as much as possible;
- do not take a shower or bath so as not to damage the device;
- to sleep, put the device next to you in bed;
- for recordings longer than 24 hours, change the electrodes every 2 or 3 days;
- If the electrodes cause a skin reaction, change them more often and do not hesitate to move them a few centimeters on an unirrigated area.
At the end of the 24 hours, simply peel off the electrodes and return the device, wires, and electrodes to the cardiology office. It is also possible to go with the device still connected to the cardiology office where the machine will be removed.
How to choose an ECG Holter?
Invented by an American biophysicist named Norman Holter, the recording of the electrical signal by the Holter ECG was formerly done on audio cassettes that had to be changed every hour.
Today, holter ECGs have evolved a lot. Registration is done using removable cards and the devices have been increasingly miniaturized, reducing cable length and improving patient comfort, while remaining very reliable. In addition, extraneous noise has been reduced. Similarly, processing consoles are becoming more and more sophisticated. Some boxes now have their own analysis system.
There are different models of ECG holters such as:
- ambulatory patients capable of memorizing the various electrical signal data without the help of removable support;
- resistant to immersion.
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