Multi-day telemonitoring of ECG in 12 leads

In the routine clinical practice of cardiologists, the method of Holter ECG monitoring (syn. 24-hour ECG monitoring) is widely used, which at the time of its appearance became a breakthrough in the diagnosis of cardiac arrhythmias and

What is the advantage of multi-day ECG monitoring over Holter monitoring, and for what diagnostic purposes is it intended? Let’s find out!

The need for long-term ECG monitoring is primarily due to the presence of rare (1-2 times a week or less) arrhythmic events or clinically significant symptoms (fainting or palpitations) in a number of patients. Whereas the Holter monitoring method will not allow recording these events.

The longer the observation time, the more data is recorded and the more complete the picture is formed in the conclusion. In addition, long-term ECG monitoring allows you to safely select the optimal antiarrhythmic and anti-ischemic therapy for patients.

What is the difference

Now let’s talk about the fundamental differences between these two diagnostic methods.

1. Registrar

This is a device that the patient always carries with him during the examination. The size of the recorder for multi-day ECG monitoring is close to a box of matches, and its weight is less than 30 grams. This allows you to wear it for a long time without problems.

Unlike the Holter recorder with its large number of wires, the recorder for long-term ECG monitoring has only one cable and is attached to the front surface of the chest with Velcro. Thus, the device is practically invisible and does not create any discomfort to the patient.

2. Data transfer method

In the case of Holter monitoring, data are transmitted only after the end of the study and the removal of the recorder from the patient. With multi-day ECG telemonitoring, data transmission goes in parallel with the examination. So the doctor can monitor the patient’s condition almost online and give recommendations.

3. Efficiency of data decryption

Another important advantage of the method of multi-day ECG monitoring. The result is ready almost immediately after the end of the study (sent to the patient by e-mail). There are also no restrictions on the territory of the survey, since the data is transmitted via the Internet.

Number of leads

Some attentive readers will ask: “What is the significance of the number of leads in the registrar?”.

Simply put, leads are the number of Velcro wires connected to the recorder. The smaller they are, the easier it is to carry the device.

However, it is the presence of 12 leads (as with a standard ECG) that makes it possible to compare these studies and, most importantly, to more accurately detect ischemia and determine the localization of ventricular arrhythmias. This feature gives the method an advantage over loop ECG recorders (a device implanted under the skin for long-term ECG recording).

Options for carrying out and indications

There are several options for long-term ECG monitoring:

The study is carried out during the time planned in advance (2, 3, 5 days, etc.).
Study “before the event”, that is, before the appearance of clinically significant symptoms (fainting, palpitations, etc.).
For patients with suspected or existing coronary heart disease (CHD), the multi-day ECG telemonitoring method will be useful in the following cases:

Suspicion of vasospastic angina

Presence of rest angina and absence of ischemic changes on rest ECG and Holter ECG monitoring
To detect episodes of painless ischemia in patients with coronary artery disease (this affects the prognosis of the disease)
To assess the effectiveness of ongoing anti-ischemic therapy for the most accurate selection of the dose of the drug
Among other indications, we would like to pay special attention to the diagnosis of congenital long QT syndrome (QTQT).

The QT interval on the electrocardiogram is the same vital indicator of the human body as the pulse rate or respiratory rate. But we ourselves, unfortunately, cannot measure it, even using smart watches. Its duration is inversely related to the pulse rate, therefore, for convenience and comparison, the so-called “corrected QT” is calculated.

Both lengthening and shortening of this interval is dangerous, since all this can become a prerequisite for the development of dangerous arrhythmias.

SUIQT is a relatively common congenital disease (1:2000-1:2500), which is characterized by the development of life-threatening ventricular arrhythmias. And paradoxically, SQT does not always manifest as QT prolongation on the resting ECG.

It is the method of long-term ECG monitoring that makes it possible to obtain not only a detailed assessment of the duration of the interval for the entire observation time, but also additional calculated indicators (“QT-dynamics”) that facilitate the diagnosis of this disease, as well as predicting the risk of developing ventricular arrhythmias based on an assessment of the heterogeneity of electrical processes in the ventricular myocardium in patients without SUIQT.

This method will also be useful for patients with dilated and hypertrophic cardiomyopathies, sinus node dysfunction, Brugada syndrome, primary pulmonary hypertension, etc.

In conclusion, we can say that the method of multi-day ECG telemonitoring is the next evolutionary stage in the development of the method of long-term ECG recording after Holter monitoring. Its use makes it possible both to facilitate the data collection procedure itself and to obtain more valuable information about the operation of the electrical system of the heart.