Overview of rheovasography the essence of the study when and who needs it

Rheovasography is one of the methods of diagnosis in which the blood circulation in the lower and upper limbs of the patient is examined. Blood circulation investigated in this way is called hemodynamics. It reveals a picture of the state at the time of the examination of the cardiovascular system, and also allows you to assess vascular tone.

In human life, the main load falls on the lower extremities, therefore, most often, a study is prescribed for this part, this allows you to assess the blood vessels of the legs and prescribe the correct treatment.

It is possible to undergo reengineering not only in the direction of a doctor, but also independently. This study is carried out in many specialized clinics at an affordable cost. If you need reovasography of the lower extremities in Moscow, you can contact the following addresses:

  • 2nd Tverskaya-Yamskaya Lane, Building 10 – OJSC “Medicine”.
  • Banny Lane, Building 2 – SVSR.
  • MKRN Novogorsk in Khimki – Design Bureau No. 119.
  • St. Novozavodskaya, house 14a – clinic number 2.
  • St. Lyapidevsky, d. 14/1 – “Dobromed”.
  • St. Budayskaya, Building 2 – Russian Railways OJSC, Central Design Bureau No. 2.

Depending on the institution in which the procedure is carried out, its reputation, location, the quality of the equipment on which the lower limbs reovasography is performed, the price may fluctuate. Cost – from 800 to 2500 rubles.

Rheovasography is one of the non-invasive methods of examination, where penetration into the body is not required. For carrying out use high-frequency current. This study is not used for the vessels of the head, in which case the diagnosis is called rheoencephalography.

Rvg (rheovasography) of the lower extremities: features, principle of conduct, decoding and norms

Many severe pathologies originate in seemingly small, insignificant manifestations, which rarely anyone pays attention to. Even mild vascular changes can subsequently lead to stroke, heart attack, amputation of limbs.

Vascular diseases arise for various reasons, it can be psycho-emotional stress, an unbalanced diet, an intense rhythm of life.

The earlier an unstable state, the onset of the disease is detected, the more competent and adequate therapy is selected, and this is an important aspect for maintaining health.

In medicine, preference is given to non-invasive research methods, which are very informative, one of them is lower limb rheovasography (RVH). We’ll take a closer look at this method: for what purpose rheovasography is performed, to whom it is shown and how the examination results are decoded.

RVG is one of the latest modern non-invasive diagnostic methods. It is used to examine the blood vessels of the legs and arms.

The technique helps to identify arterial obstruction sites that lead to inflammation. There is also the opportunity to examine the vessels, identify violations associated with their work.

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Principle of operation

The essence of the method is to detect the resistance of the skin area through which a harmless electric current is passed.

In sensors attached to the body, a certain force and frequency of charge oscillations are set.

If the blood flow is not intense enough, then the resistance of the skin and tissues becomes higher, and vice versa.

The process of performing the survey and the information output of the results is similar to an ECG. Based on these data, the doctor makes a diagnosis regarding the study area.

There are two types of rheovasography:

  1. Identification of blood flow pathologies in the legs.
  2. The study of the vascular channels of the hands.

Based on the statistics of diseases, the diseases of the lower extremities are most common, therefore rheovasography of this species is used more often.

Rheography is a method of studying the blood supply to organs and parts of the human body. It consists in measuring and graphically displaying pulse fluctuations of impedance, depending on the blood supply to the organ. (Impedance is the resistance of tissues to the passage of high-frequency alternating current.)

The idea and the first survey technology were formulated by N. Mann in 1937 and further developed by Austrian and Soviet scientists.

The scope of rheography is practically unlimited: the brain, the ocular membrane, limbs, heart, lungs, liver and other internal organs. For procedures on individual parts of the body, there are names:

  • REG – rheoencephalography (brain);
  • ORG – ophthalmoreography (choroid);
  • RVG – rheovasography (vessels of the upper and lower extremities).

What is this – rheovasography (RVH) of the vessels of the upper and lower extremities? Consider all the nuances in order.

RVG allows you to diagnose tissue blood flow pathologies (ischemia and hyperemia),

(narrowing) vascular lesions, but not able, for example, to reliably determine

(protrusion of the vascular wall).

Rules of preparation and procedure

To conduct rheovasography of the vessels of the upper and lower extremities, an electrocardiograph (ECG apparatus), special electrodes and a rheographic prefix are required. The task of a medical professional is greatly facilitated if computerized recording of indicators is used. In the study, a high-frequency current is used, which does not bring any unpleasant sensations.

Blood is able to conduct electric current, for this reason, the resistance changes in different phases of the bloodstream. Dependence here is inversely proportional: with greater blood supply – less tissue resistance. From high to low there is a constant fluctuation. The rheovasogram graphically displays the passage of the pulse wave, the amplitude increases with increasing blood supply and, conversely, decreases with its decrease. The doctor of functional diagnostics sees the disturbance on the graph and can draw conclusions about the nature of blood flow.

Preparation for RVG requires the following simple restrictions from the patient:

  • one day before the procedure, stop taking medications that affect blood flow and vascular patency;
  • at least 8 hours do not smoke, do not chew nicotine gum and do not sniff tobacco;
  • within 2 hours do not eat or undergo intense physical exertion;
  • 15 minutes before the procedure, take a horizontal position, relax and lie down in silence.

The temperature in the office where the examination takes place is set at 20-23 ° C, because the patient will have to remove everything that covers and squeezes his hands or feet, and for a while to lie still.

To register impedance fluctuations, electrodes (aluminum, lead, brass, etc.) are fixed on both limbs of the patient, and they are positioned strictly symmetrically, and the skin at the attachment points is degreased with alcohol.

Depending on whether the entire limb or part of it becomes the subject of research, the doctor determines the location and method of applying electrodes (longitudinal or transverse).

To study the weakened peripheral blood flow, a longitudinal method of attachment is usually chosen (on one surface of the limb), in other cases, transverse (at the same level, but opposite sides).

To study the dependence of hemodynamics on external conditions, the result of RVG at rest is often compared with a rheogram after various tests: pharmacological, compression, or physical exercise tests.

For example, to eliminate deep vein thrombosis, a compression test is used: the limb is cuffed for a short time, and after removal, the RVG is repeated. To distinguish between functional and organic disorders of vascular patency, a test with nitroglycerin is used (0,5 mg under the tongue, after 5 min – repeated RVG).

To compare rheograms with cardiac activity, simultaneously record, if possible, more electro- and phonocardiograms (ECG and FCG).

Main indications

Reovasography of the lower extremities is carried out with the aim of studying the quantitative indicators of the state of the vessels. Synchronous wave readings are equal to the heart rate. According to the waves, one can judge the filling of blood vessels, depending on the phase of the heartbeat in a certain time period. As a result of the study, RI (rheographic index) is derived.

It is calculated by comparing the amplitude of the waves with the height (calibration pulse). The value of RI directly depends on the filling of blood vessels with blood, with its help it is possible to calculate the total intensity with which the organ is filled with arterial blood. The following parameters are also referred to the main indicators: outflow value; elasticity; peripheral resistance.

The result of RVG of the lower or upper extremities (rheogram) is a complex quasiperiodic curve, the interpretation of rheovasography is based on the study of the properties of the averaged rheographic wave:

  • high-quality – the presence of “peaks”, the steepness and slope of the “rises” and “descents”;
  • quantitative – the amplitude value, the length of some time intervals, etc.

Based on the found values ​​and special formulas, control indices are calculated:

  • rheographic (RI, registers the intensity of arterial blood flow);
  • elasticity (IE, reflects the state of the walls of the arteries);
  • peripheral resistance (IPA);
  • values ​​of venous outflow (VO).
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The main indicator is considered to be RI: by its size they judge the patency of the riverbed. IPS and HE, in contrast to IE and RI, are only indirect numerical characteristics.

Reference intervals for indices are not shown here for the following reasons:

  1. In rheography, there was no common terminology and calculation methodology: the coefficients of the same name, calculated under similar conditions for representatives of the same age group in different medical facilities, can differ by a factor of ten.
  2. Norms are determined separately for each segment of the limb: shoulder, forearm, hand, thigh, lower leg, foot.
  3. The values ​​of some indicators depend on age: for example, in elderly people, RI is lower than in healthy youth (especially the vessels of the lower leg).

It should be noted that there are no significant differences in the results of RVG by gender, geography or ethnicity.

It is possible to identify a disease and prescribe a procedure based on a person’s complaints. The patient should list the symptoms manifested over a certain period of time.

The RVG results show a curve. Wave decoding is based on qualitative and quantitative values. These include: the steepness of the descents and ascents, intervals, amplitude, peaks.

Based on the values, control indices are derived, which are:

  • rheographic – it controls the strength of the blood flow in the arteries;
  • arterial wall shows IE;
  • IPS – peripheral resistance index;
  • numerical value of venous outflow.

The most basic of the indicators is RI – the reographic index.

Obtaining the results of the study does not take much time. Within 30 minutes, the specialist can decrypt the resulting line and display the indices. RVG decryption is displayed in Ohms.

As mentioned above, RI shows the total volume of filling of blood vessels. With indicators of 0,05 ohms and above, we can say that their condition is normal.

With deviations of one unit, mild insufficiency is observed. If RI is sharply reduced, the patient is diagnosed with a violation of blood supply.

The standards for vascular tone data without deviations are considered to be from 0,4. Values ​​that do not reach the indicated units already go as violations. The lower the indicator, the lower the tone of the vascular wall.

The outflow index shows the speed of blood flow in the venous channel. RVG should range from 0,2 to 0,5. Everything that exceeds this line speaks of serious illnesses.

IPA responsible for counteracting the vascular canals should be in the range of 0,2-0,45. With obvious pathologies of blood flow, the index can be exceeded or underestimated.

Violations that were recorded during the RVG do not always indicate damage. The resulting index may carry the functional nature of the deviations.

Often such results are obtained when they do not comply with the preliminary training. There are two additional tests. They help determine what is actually happening, a temporary spasm or pathology:

  1. Nitroglycerin. Using the drug, the rheovasography procedure must be completed several times. The first occurs before the use of the drug, and the second after its action. The doctor receives data from two studies and analyzes. If the comparable results do not differ significantly, then we can conclude that there is a pronounced pathology on the face. In the case when the drug has affected and the indicators have improved, one-time violations caused are assumed.
  2. Compression. The essence of the procedure is to use a cuff that squeezes the necessary area of ​​research. As in the case of the drug RVG, the patient passes twice. Before applying the cuff on the limbs and after. This test helps to determine how quickly the blood supply is restored when deep veins overlap.

At the same time, the patient does not receive any radiation or other negative effects on his body. The method is more than safe and informative. Due to this, this diagnosis is relevant in medical practice.

Survey Benefits

Rheovasography of vessels of the lower extremities is used both for the initial study of vascular pathologies and for monitoring the development of the disease. Indications are:

  • Atherosclerosis, which often contributes to the violation of proper nutrition of tissues and narrowing of the gaps in the artery.
  • Diabetes. Reovasography of the upper and lower extremities is performed. This ailment can lead to micro- and macroangeopathies, which subsequently develop a diabetic foot.
  • Raynaud’s disease. Neurocirculatory asthenia is characteristic, periodic spasms of the peripheral arteries are possible.
  • Severe headaches that occur due to violations of the outflow of venous blood, as well as spasms of arterial vessels.
  • Chronic cerebral pathologies, intracranial hypertension.
  • Neurocirculatory asthenia, which depends on the lability of vascular tone.
  • Diseases of the venous bed, which contribute to violations of the outflow of blood, in particular along the veins of the legs.
  • Thrombophlebitis, leading to the formation of blood clots on the walls of blood vessels.
  • Phlebeurysm.
  • Embolism when a blockage occurs in the bloodstream.
  • Obliterating endarteritis, which can lead to lameness.

In the absence of pronounced RVH diseases, it is recommended in cases of numbness of the extremities, with the appearance of bluishness and seizures, with loss of sensitivity, discoloration of the skin, and edema.

Each study has both its advantages and disadvantages. They can be associated with the technical side or with the professionalism of the staff. It is important that all the negative sides can be corrected and debugged for the better in the diagnostic process. The advantages of RVZ are as follows:

  • Non-invasive method. A significant positive point is that the patient is not exposed to unpleasant and painful effects, for example, catheterization of veins. For research, a specially designed equipped office is not required, enough necessary devices.
  • Ease of carrying out. A big plus for the staff. A qualified nurse can take a rheovasogram; its task is to apply electrodes and turn on the resograph. Analysis of the results will be done by the doctor.
  • Inexpensive and affordable equipment for research.
  • Safety procedures. RVG is possible in children and pregnant women.
  • Reliable information. Vascular patency, quality of blood outflow, pathology and their prevalence level are determined with great accuracy.
  • It is possible to conduct differential diagnosis of vascular lesions from functional impairment.

Suspected disease

Some symptoms may indicate obvious diseases that can be clarified during the examination:

  • atherosclerotic lesion due to stenosis or complete closure of the supplying artery;
  • autoimmune pathology with irregular hemodynamics in the hands;
  • diabetes mellitus with complications;
  • inflammation of the walls of the arteries from the inside;
  • varicose veins.

In addition, with the help of RVG, the etiology of the disease can be determined. Understand what influenced the subsequent development of pathology, the structure of the channels or the reasons caused by the lifestyle.

How to prepare for RVG?

What is RVG and how to prepare for it, usually says the doctor conducting the study. A reliable assessment of the characteristics of blood flow through the vessels occurs provided that the patient’s veins and arteries are not affected by additional external or internal factors (pressure clothing, belt, excitement, cold in the office, drugs, nicotine, coffee). To do this, before the rheovasography procedure, you must:

  • stop taking drugs that affect hemodynamics (with the permission of the attending physician);
  • do not smoke before the examination for at least 7 hours;
  • the last meal in 2 hours, do not drink coffee a day;
  • limit exercise;
  • the study is carried out in a warm room, the patient takes off almost all the clothes and lies calmly on the couch for 10 minutes to relax.

Any doctor will say that these factors can change the indications of RVH of the upper and lower extremities, so you need to carefully prepare for the upcoming study.

The procedure itself is quick and does not require special preparation.

The patient should sit on the couch, on the back. The doctor attaches the sensors in the form of suction cups to the examined area. Then for 15 minutes he observes the indicators.

Before RVG recommend:

  • Before the examination, you need to relax the muscles, lie down for 20-30 minutes;
  • stop taking drugs that affect the bloodstream and blood vessels at least a day before the study;
  • do not drink alcohol a few days before the procedure;
  • those who smoke need to abstain for a couple of hours before reovasography;
  • On the day of the examination, do not overwork and try to avoid emotional stress.

This preparation guarantees the most accurate result of the testimony obtained during rheovasography.

In case of violation of the rules must conduct an additional trial. This will allow you to compare the results of the indices and make the correct diagnosis.

Rheovasography of the lower extremities has very small disadvantages, these include the following points:

  • Human factor. If there are too many patients, a nurse’s lack of proper rest can lead to dispersal of attention, and this can affect the quality of registration. If the working conditions, the rest regimen are observed, the qualifications of the medical staff are high, then this minus is absent.
  • The quality of technology. Reographic consoles can interfere, which affects the results. The use of computers eliminates such shortcomings in the study.

How is the study going

Rheovasography is a painless procedure and partly resembles the removal of an electrocardiogram. The patient requires a little preliminary preparation for the study. It includes:

  1. Termination of any physical activity at least 15 minutes before rheovasography.
  2. Quitting smoking at least 2 hours before the procedure. Nicotine contained in tobacco causes vasoconstriction and, therefore, can cause distortion of the results.
  3. Stop taking medications the day before the study. This is due to the fact that some of them are able to affect the state of the vascular wall, blood flow. If drug withdrawal is not possible (for example, with antitumor therapy), the doctor should be warned about this.
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RVG is carried out in a supine position, for this a couch is provided. Investigated limbs (legs and arms) should be exposed. After the patient has taken a comfortable position, his skin in the area of ​​application of the sensors is degreased with alcohol.

Depending on the blood flow of which limbs will be analyzed, the location area of ​​the recording electrodes differs. When evaluating the functional activity of the vessels of the hands, the sensors are superimposed on the fingers, hands, forearms and shoulders. If reovasography of the lower extremities is performed, electrodes are placed on the feet, legs and hips. There are no other differences between the study of limbs.

After installation of the electrodes, a record is made of the indicators. Curve results are displayed on the screen.

In the office where the procedure itself takes place, it should be warm enough, as the patient is forced to take off his clothes, freeing his limbs for examination.

In order for the fixed electrodes to show accurate data, a person must lie still. For convenience, a soft couch is available.

Before fixing the sensors, the surface oily layer is removed from the skin. Install them clearly according to the principle of longitudinal or transverse placement. It depends on the investigated limbs.

Preparation and conduct

Preparation for rheovasography of the lower extremities is not at all complicated, however, all the requirements that are presented before the study must be observed.

  • 15 minutes before the study, the patient should completely relax, get a preliminary rest.
  • Those who smoke in two hours should completely eliminate the flow of nicotine into the blood.
  • If you are undergoing treatment with any medications, you must abandon the drugs one day before the REV.
  • When undergoing rheovasography, the limbs should be freed from clothing.

Rheovasography is a simple and not lengthy procedure. The person during her conduct is located on his back, on the couch. A functional diagnostic physician attaches (usually with the help of suction cups) sensors to the skin of the examined area of ​​the hands or feet. The procedure itself lasts about 10-15 minutes. Before it is carried out, it is necessary to carry out several simple preparatory recommendations:

  • Preliminary rest for complete muscle relaxation and normalization of blood flow in them (15-20 minutes before the start of the examination).
  • For several days (at least 24 hours), it is necessary to stop taking medications that affect the level of blood pressure and the state of the vessels.
  • It is necessary to exclude alcohol intake a few days before the examination.
  • For smokers, for several hours you must refrain from smoking.
  • On the day of rheovasography, it is advisable to try to avoid severe physical or emotional stress.

Implementation of simple preparatory recommendations before rheovasography will allow you to get the most high-quality and objective research result.

Rheovasography of the upper and lower extremities: what is it and how is it performed

To study the circulatory system, X-ray contrast (RK) or magnetic resonance (MR) angiography, ultrasound dopplerography (UZDG) and color duplex angioscanning (DS) are also used. These methods, unlike RVG, allow not only to evaluate the tone and patency of the vessels, but also to consider them in cross section or in three-dimensional form against the background of other anatomical structures.

RK angiography is a radiological method, which means it is not applicable when examining pregnant women and young children.

Due to the severity of the procedure (anesthesia, antihistamine injection, catheterization of the vessel, the introduction of iodine contrast and x-rays), the study has additional contraindications:

  • thrombophlebitis;
  • iodine allergy;
  • heart or kidney failure.

MR-angiography does not carry a radiation load on the patient’s body, but MR-tomograph is a complex and expensive equipment, therefore it can only be examined on it at regional hospitals. The price, accordingly, will also be “regional”: an order of magnitude higher than the cost of RVG.

Ultrasound studies of blood vessels based on the Doppler effect are informative, harmless and more accessible than MRI. Nevertheless, the probability of finding the right device in the nearest clinic is still far from unity.

Duplex angioscanning is a comprehensive option because the study takes place in parallel in two modes: conventional ultrasound (gives local two-dimensional black and white projections) and ultrasound. By the way, there is no “triplex” scan: it’s just a marketing ploy using the third color “window” on the UZista’s monitor.

The examinations listed in this section are not “first-choice” diagnostics (except, possibly, ultrasound scan), but are prescribed after the RVG detects deviations from the norm.

So, the basic principles of rheovasography and its differences from other methods for diagnosing limb vessels are now known to you.

And although this is one of those examinations that everyone can “prescribe” for himself without harm to health and wallet, still remember that only the doctor who performed the diagnosis can decipher the results correctly: the values ​​of the main coefficients significantly depend on the type of device .

After receiving the reovasogram, the decryption time comes, which is carried out by a qualified specialist. This is the main point of the study, all pathologies are discovered here and the question of further treatment is being resolved. The interpretation of rheovasography of the lower extremities includes the following important points:

  • The main emphasis is the study of RI. A value of 0,04 indicates a sharp decrease in the norm, an index of 0,04-0,05 indicates a moderate decrease. RI above 0,05 is considered normal.
  • The elasticity index (IE). A sharply reduced indicator is less than 0,2. Moderately reduced – 0,2-0,4. Normal is 0,4.
  • To determine the outflow of blood in the vessels, calculate the corresponding index, the norm of which is 0,2-0,5. If the value is less, the outflow is facilitated; an indicator above 0,5 indicates difficulties in outflow.
  • Indicators of peripheral resistance: more than 0,55 – overstated; less than 0,15 – underestimated. The norm is 0,2-0,45.

Do you remember how you spent your family time before the first series appeared on the central channels? Can you imagine a ride to work on a bicycle? and the nearest grocery at a distance of 5 km?

Technical progress raises the standard of living, but, oddly enough, not its quality: most of us spend a working day in front of the monitor, rest in the same place, and even with popcorn and french fries.

Many people prefer to forget that a diet rich in fats, but poor in fiber, contributes to the deposition of atherosclerotic plaques.

It can be said mildly: “malnutrition and lack of exercise increase the risk of developing cardiovascular diseases”, but in fact, an unhealthy lifestyle sooner or later leads to vascular pathologies. Early diagnosis in this situation will help to identify functional disorders before they become irreversible. Rheovasography, along with ultrasound, can become a method of mass diagnosis of the population.

After decoding the received rheovasogram, the doctor calculates several indicators, which include:

  • Elasticity index – shows the state of the walls of the arteries (their elasticity). Normally, it should be higher 0,4. A decrease below normal indicates poor elasticity of the walls of the arteries with a corresponding deterioration in blood flow in them. A decrease in this index below 0,2 is a prognostically unfavorable sign.
  • Rheographic index or outflow index – shows the possibilities of the venous bed, normally this indicator is 0,5. An increase indicates a worsening of venous outflow of blood.
  • Index of peripheral resistance – normally varies from 0,2 to 0,45, it characterizes the intensity of blood flow in small vessels (microvasculature).

Modern devices for rheovasography calculate the main indicators of the result using the built-in processor, which greatly simplifies the routine of the doctor.

Also during this study, additional drug tests may be performed. Usually, during the procedure, the test person is given nitroglycerin, which affects the functional state of the arteries. By changing it, the doctor can judge the structural state of its walls. Compression tests are also carried out, which consist of a temporary constriction of the main vessels of the limb, followed by their release and the study of the rate of renewal of blood flow.

Due to the absence of any negative effects on the body, there are practically no contraindications for rheovasography. It is a safe and informative method of functional diagnostics, which has not lost its relevance today.

Additional samples

To identify hidden pathologies, functional pharmacological tests can be used:

  • Nitroglycerin. After resorption of nitroglycerin, RVG is performed, after which the result is compared with the usual one. This is necessary in order to distinguish between organic contractions and functional spasms.
  • Compression. Used in the study of deep vein thrombosis. For comparison with the usual indicators of RVG, a cuff is placed on the thigh and indicators are fixed after it is removed.
  • Cold. It is carried out to diagnose various pathologies in the hands. Cold water is applied. The rheogram is removed three times after a certain time, the results of the restoration of blood flow are compared, conclusions are drawn. Negative test – on the restoration of RI in the 7th minute. Positive test – slow recovery up to 30 minutes.

Altered parameters recorded using rheovasography do not necessarily indicate damage to the walls of the vessels. Signs of a blood flow disturbance can be caused by a spasm that is episodic (functional) in nature: this result can be obtained if the rules of preliminary preparation are not observed.

Svetlana Borszavich

General practitioner, cardiologist, with active work in therapy, gastroenterology, cardiology, rheumatology, immunology with allergology.
Fluent in general clinical methods for the diagnosis and treatment of heart disease, as well as electrocardiography, echocardiography, monitoring of cholera on an ECG and daily monitoring of blood pressure.
The treatment complex developed by the author significantly helps with cerebrovascular injuries and metabolic disorders in the brain and vascular diseases: hypertension and complications caused by diabetes.
The author is a member of the European Society of Therapists, a regular participant in scientific conferences and congresses in the field of cardiology and general medicine. She has repeatedly participated in a research program at a private university in Japan in the field of reconstructive medicine.

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