Electrocardiography is an inexpensive and very informative method of diagnosis, which allows to identify a number of heart diseases with causing the patient a minimum of inconveniences. The result of the study is the cardiac ECG - that is, the electrocardiogram in the form of a graph that shows the activity of the organ.
How do ECG hearts?
The principle of the study is to record fluctuations in the potential difference that accompany the contractions of the heart muscle and are transmitted to the cardiograph through the electrodes. Potential differences are called leads, and for their registration, electrodes are placed on:
- the right hand;
- the left hand;
- the left leg.
Moreover, each lead has two poles - plus and minus. In total they are six. On the right leg, the electrode is used as a grounding electrode, and the potential is not recorded from it.
In addition to leads on the limbs, in cardiography, the difference in the potentials of the thoracic leads is estimated - in general there are nine of them, but usually only six, and each has only one pole. These doctors set the electrodes on the chest at certain points.
Preparation for ECG of the heart
No special measures are taken before the study. Doctors advise not to worry during ECG recording, especially since this method of diagnosis is non-invasive, and the patient does not experience any discomfort.
It is not recommended to use oil creams before cardiography. their remnants on the skin can distort the result of the measurements. To prevent such a place of fixing the electrodes, degrease with alcohol. Then a conductive gel is applied (it can be replaced by wet gauze wipes) and the sucker is fixed.
After that, the doctor turns on the device and begins recording the cardiac ECG - as a rule, the doctor diagnosing it can decipher it. However, if there are serious deviations in the chart, further consultations are conducted only by the attending cardiologist.
The whole procedure takes no more than a couple of minutes. Because suckers are attached only to the naked body, it is worth wearing comfortable clothes (tights will have to be removed in any case). If the patient has severe shortness of breath, in order to see cardiac arrhythmias on the ECG accurately, during the measurement, he is recommended to sit and not lie.
What shows the ECG of the heart?
This diagnostic method allows:
- Analyze the frequency of cardiac contraction and their regularity.
- Identify the violation of the exchange of magnesium, calcium, potassium and other electrolytes.
- Recognize damage to the myocardium, concomitant heart attack or ischemia.
- To reveal hypertrophy of the left ventricle.
On the chart of the cardiogram, the teeth P, Q, R, S, T are visible, and a small U tooth can be seen. They all correspond to a certain phase of contraction and relaxation of the heart muscle.
ECG abnormalities
First of all, arrhythmias and cardiac blockages on the ECG are revealed - these are changes in the normal frequency and regularity of the pulse.
It is possible to classify these violations in the following way:
- Tachycardia is an accelerated heartbeat, that is, an increase in heart rate; it is physiological (during exercise) and pathological (worries even at rest).
- Bradycardia - low heart rate (up to 70 beats per minute).
- Extrasystolia - a violation of the heart, in which the muscle makes an extraordinary reduction.
- Atrial fibrillation is a form of tachycardia for which
the chaotic electroactivity of the atria is inherent and the impossibility of their coordinated reduction.
Deviations from the norm on the cardiac ECG are evaluated by a cardiologist, however this method of diagnosis may not be sufficiently informative. And then they assign an ultrasound (Echo-KG), which allows you to follow the work of the heart muscle in real time, see the movement of blood, consider the structure of the valves. Assign an ultrasound of the heart or an electrocardiogram, the doctor decides - with a routine examination for healthy people, usually only an electrocardiogram is sufficient.