Polycardiography

The term “polycardiography” comes from three words of Greek origin: “poly” – many, “kardio” – heart and “grapho” – depict. Polycardiography is a combined method for studying the functions of the heart, which combines the simultaneous conduct of electrocardiography (ECG), phonocardiography (PCG) and carotid sphygmogram (CAS). The method was first introduced into medical practice in 1942 by K. Blumberg, although there were attempts to study the systole of the heart earlier (in the 20s of the 20th century). Currently, polycardiography is the main method for a detailed study of the activity of the heart.

With the help of this study, the phase structure of the systole of the cardiac cycle is studied, which is very important in assessing the functional state and compensatory abilities of the cardiovascular system.

The essence of the method

Polycardiography includes three simultaneous functional studies: ECG registration in the second standard lead, mid-frequency phonocardiography from the apex of the heart, and sphygmogram of the carotid arteries.

The cardiac cycle consists of systolic and diastolic phases. The phases differ from each other in the volume of the cavities of the heart and the pressure in them.

The first phase, during which the heart muscle tenses around the volume of blood in the ventricle, is called the tension phase or general electromechanical systole. In this phase, the heart changes its configuration, intracardiac pressure increases to numbers exceeding the pressure in the aorta and pulmonary arteries. This phase consists of a period of asynchronous contraction (myocardial tension does not occur simultaneously in all parts of the heart, but spreads in waves through the muscle) and an isometric increase in pressure (the period between the closing of the atrioventricular and opening of the aortic semilunar valves).

In the second phase of systole (expulsion or isotonic contraction), portions of blood are ejected from the ventricles into the aorta and pulmonary arteries. which normally ends with the closure of the semilunar aortic valves.

After systole comes diastole (relaxation) of the heart muscle. In diastole, a distinction is made between protodiastole, the isometric contraction phase, and the ventricular filling phase.

The deviation of the electrical, mechanical and acoustic characteristics of these phases from the normative indicators allows us to establish the cause and severity of cardiac arrhythmias.

The task of polycardiography is the synchronous registration of the systolic phases of several consecutive cardiac cycles. The beginning of the first tone coincides with a rapid rise in intraventricular pressure, which corresponds to the mechanical systole of the left ventricle. The interval between the second tone determined by FCG and the notch (incisura) on the wave of the carotid sphygmogram makes it possible to detect the delay of the pulse curve in relation to the pressure curve in the aorta. At the same time, the ECG supplements the standard recording of the phases of heart contractions with data on the electrical and mechanical systoles of the left ventricle.

Advantages and disadvantages

The advantages of polycardiography are:

• non-invasive and painless procedure;
• short procedure time (to analyze the curves, it is enough to register several phases of the cardiac cycle);
• the possibility of carrying out even in patients with decompensated cardiovascular insufficiency and in an unconscious state or coma.

Polycardiography can be performed both in stationary conditions, for example, in the cardiology department, and on an outpatient basis – in a polyclinic.

Indications and contraindications

This multifunctional study is prescribed by a cardiologist. Indications for its implementation are:

• heart defects;
• rheumatic affections of valves;
• previous streptococcal infection;
• infective endocarditis;
• prognostically unfavorable arrhythmias;
• myocardial infarction;
• pulmonary hypertension;
• stenosis of the aorta or pulmonary arteries;
• malignant arterial hypertension;
• preparation for cardiac surgery.

Polycardiography is recommended to be carried out in dynamics, that is, with a certain frequency, which makes it possible to evaluate the effectiveness of the therapy.

There are no contraindications to this research method.

Preparation and methodology

Special preparation for the examination is not required. The only limitation is the refusal of physical activity before conducting polycardiography, as this may distort the results of the study.

The patient removes clothing from the torso and lies down on the couch. Electrodes for ECG recording are applied to the area of ​​the wrists and chest, sensors for recording FCG, and to the carotid arteries (for SCA) are applied to the area of ​​the apex of the heart. For the study, multichannel sensors are used. The curves are recorded at a high speed of the tape drive (not less than 100 mm/s), which makes it possible to obtain a clear record for decoding. The procedure for taking indicators lasts no more than 15 minutes.

Reading polycardiograms

Several indicators are subject to analysis:

• the duration of the entire cardiac cycle, electrical, mechanical and acoustic systoles, Blumberg systole, diastole;
• the number of heartbeats in 1 minute;
• protodiastolic time;
• phases of asynchronous and isovolumic contractions;
• periods of tension, exile;
• time of expulsion of minute volume;
• mechanical Muller-Blumberg coefficient;
• intrasystolic indicator;
• cardiac muscle tension index.

The duration of the individual phases of the cardiac cycle is measured with a transparent ruler or a special meter. A cardiologist is engaged in deciphering polycardiograms.

To analyze the obtained curves, natural and calculated indicators are determined that characterize the rhythm of the heart as a whole and its left ventricle.

Depending on the nature of the deviations of the indicators of the phases of the cardiac cycle, several phase syndromes are distinguished, which are characteristic both for pathologies of the structures of the heart and for healthy individuals under conditions of severe physical exertion. There are 5 main phase syndromes:

1. The hypodynamia syndrome develops with deep myocardial damage and disorders of the contractile function of the heart muscle (diffuse cardiosclerosis, myocarditis, toxic damage to the heart muscle, cardiac aneurysm, extrasystole, after myocardial infarction), as well as in well-trained athletes in the norm.
2. Syndrome of hyperdynamia. Hyperdynamic syndrome occurs in patients with heart defects, with sinus tachycardia, tachycardia with fever, tachycardia against the background of thyrotoxicosis, and normally in people engaged in heavy physical work.
3. The syndrome of stenosis of the ventricular outflow tract (hydraulic resistance) indicates a high load on the myocardium. Determined with stenosis of the aorta and / or pulmonary artery.
4. Volume overload syndrome. It is fixed with hyperextension of the heart cavities (with aortic insufficiency, valvular disorders, atrial or interventricular septal defects, transverse heart block, patent ductus arteriosus, bradycardia).
5. The syndrome of high systolic pressure (elastic resistance) is a companion of arterial hypertension of varying severity.

When interpreting the results obtained, it is necessary to understand that these syndromes are not a diagnosis, but a symptom complex that accompanies certain diseases of the cardiovascular system.

Polycardiography is a multifunctional dynamic examination of the state of the heart and blood vessels, which is used as an additional diagnostic method in making a diagnosis.

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