RU2320270C1 - Method for diagnosing endothelial dysfunction in adolescents suffering from arterial hypertension - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: method involves determining systolic blood circulation speed and pulsation index. Sphygmomanometer cuff is applied and pressure is increased in it 50 mm of mercury column above systolic blood pressure. Radial artery is located 3-5 cm distal relative to wrist joint, pressure is held in the cuff for 30 s and the first compensatory wave blood circulation speed characteristics are determined. Systolic blood circulation speed increase being found in combination with pulsation index increase when compared to control group, endothelial dysfunction is to be diagnosed. Experts propose the shown reasons and adjusted formula version to be analyzed in compliance with the written data.

EFFECT: wide range of applications.

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Description

The invention relates to medicine, namely to methods for diagnosing endothelial dysfunction by mechanical stimulation of the endothelium of the radial artery with increased post-compression blood flow in adolescents with arterial hypertension.

It is known to use the method of mechanical stimulation of the brachial artery endothelium with increased blood flow to diagnose its dysfunction.

This method includes evaluating the function of the endothelium of peripheral arteries, based on the measurement of peripheral vascular resistance. In diagnostics, linear sensors of 7-8 MHz equipped with a Doppler function are used. The sensor is placed in the longitudinal direction on a fixed area of the upper limb (most often 2-15 cm above the ulnar fossa). Blood flow velocity is measured by the Doppler method using a combination of two sensors located at an angle of 120 ° with respect to each other and 45-60 ° with respect to the vessel, or one linear sensor. Measurements are taken at rest and after the action of an endothelium-dependent stimulus. The study is recommended to begin after a 10-15 minute stay of the patient in a horizontal position. The stimulus causing endothelial-dependent dilatation of peripheral arteries is usually reactive hyperemia. In the cuff located distal to the study site, a pressure of 200-300 mm Hg is created for 4-10 minutes, then the pressure is eliminated, in the proximal segment of the artery blood flow and blood flow velocity increase, i.e. reactive hyperemia is created. Measurements are taken every 15 seconds (Zateishchikova A.A., Zateishchikov D.A. “Endothelial regulation of vascular tone: research methods and clinical significance.” “Cardiology”, 1998, N9, p. 71).

The disadvantage of this method is the duration of the study is 20-30 minutes, the excessive complexity of the study is to keep the sensors in a certain position for a period of 20-30 minutes, which requires additional devices (for example, for mounting sensors, measuring angles, etc.) and attracting another researcher. The choice of location zone (brachial artery) seems to be insufficiently rational, because it is also the zone of application of the cuff of the sphygmometer, which can affect the final result. In addition, when performing research using this technique, subjective unpleasant sensations occur in patients when air is injected into the cuff and high pressure is kept in it for 4-10 minutes, which makes the use of this diagnostic method practically impossible in the following categories of patients: pregnant, children and adolescents, the elderly and senile.

The closest technical solution, selected as a prototype, is a method for determining the sensitivity of the brachial artery to shear stress on the endothelium as a method for assessing the state of endothelium-dependent vasodilation using high-resolution ultrasound in patients with arterial hypertension, including mechanical stimulation of the peripheral artery endothelium with increased blood flow after arterial occlusion and giving an idea of the state of endothelium-dependent vasodilation. The study was carried out using a 7 MHz linear sensor with a phased array of the Acuson 128 × P10 ultrasound system. The brachial artery was located in a longitudinal section 2-15 cm above the elbow. In the initial state, the maximum rate of arterial blood flow was measured. Then, to obtain increased blood flow around the shoulder, a cuff of the sphygmomanometer was placed (above the location of the brachial artery) and pumped to a pressure of 50 mmHg. exceeding systolic blood pressure for 5 minutes. Immediately after releasing air from the cuff, blood flow in the artery was measured for the first 15 seconds. Changes in blood flow during reactive hyperemia were determined as a percentage of the initial value (Ivanova O.V. et al. "Determining the sensitivity of the brachial artery to shear stress on endothelium as a method for assessing the state of endothelium-dependent vasodilation using high-resolution ultrasound in patients with arterial hypertension." “Cardiology”, 1998, No. 3, pp. 37-41).

The disadvantage of this method is the obligatory availability of an expensive high-resolution ultrasound machine and, accordingly, the high cost of this study. In addition, the choice of location zone (brachial artery) seems to be insufficiently rational, because it is also the zone of application of the cuff of the sphygmometer, which can affect the final result. There is a occurrence of subjective unpleasant sensations in patients when air is injected into the cuff and the high pressure is kept in it for 5 minutes, which makes it difficult to perform this study. Measure only maximum blood flow velocity.

A method for the diagnosis of endothelial dysfunction by mechanical stimulation of the radial artery endothelium with increased post-compression blood flow in adolescents with arterial hypertension during a patent search was not found.

The objective of the invention is to expand the diagnosis of arterial hypertension in adolescents through the use of the proposed method for the diagnosis of endothelial dysfunction by mechanical stimulation of the endothelium of the radial artery with increased post-compression blood flow.

This task is achieved in that a method for diagnosing endothelial dysfunction in adolescents with arterial hypertension, including determining the systolic blood flow velocity, applying a cuff of the sphygmomanometer and increasing the pressure in it by 50 mm Hg higher than systolic blood pressure, characterized in that the pulse index is additionally determined, while the radial artery is located 3-5 cm distal to the wrist joint, the pressure in the cuff is kept pumped for 30 seconds, the blood flow velocity of the first compensatory wave is determined and, if there is an increase in systolic speeds in combination with an increase in the pulsative index compared with the control group diagnose endothelial dysfunction.

The method of mechanical stimulation of the endothelium of the radial artery with increased post-compression blood flow after arterial occlusion gives an idea of the state of endothelium-dependent vasodilation (EDVD). The sensitivity of arteries to the speed of blood flow is explained by the ability of endothelial cells to perceive the shear stress acting on them from the side of the current blood, which causes a "shear" deformation of these cells.

The study began after a 10-15 minute stay of the patient in a horizontal position. The stimulus causing endothelial-dependent dilatation of peripheral arteries was reactive hyperemia. Endothelial function was assessed by determining the rate of blood flow in the radial artery, which was located 3-5 cm distal to the wrist joint. In the initial state, the velocity parameters of the blood flow, the pulsating index were determined, then the cuff of the sphygmomanometer was applied around the shoulder according to the standard method and the pressure in it was increased by 50 mm Hg. higher systolic blood pressure and maintained this pressure for 30 seconds. A complete cessation of blood flow in the study area was noted. Immediately after a sharp release of air from the cuff, the speed indicators of the first compensatory wave were recorded, since within 15 seconds there is an equalization of the determined indicators in the vast majority of adolescents. The results obtained were correlated with the initial value of speed indicators. To exclude random errors associated with subjective factors, the study was carried out 3 times with the calculation of the average value. The study was carried out using the Angiodin Classic stationary Doppler diagnostic complex (BIOSS, Russia), using a pencil-type sensor with a frequency of 4 MHz in constant wave mode (CW). The sensor was constantly in the location zone (projection of the radial artery). When detecting an increase in systolic velocity in combination with an increase in the pulsative index, compared with the control group, endothelial dysfunction was diagnosed.

The effectiveness of the method for diagnosing endothelial dysfunction by mechanical stimulation of the radial artery endothelium with increased post-compression blood flow in adolescents with arterial hypertension is shown in the following examples.

Patient S., 16 years old. Diagnosis: almost healthy. No complaints.

Patient A., 17 years old. Diagnosis: arterial hypertension of the II degree, I-II stage, a high degree of risk. He was in the pediatric ward from 04/13/2006 to 04/20/2006. Complaints of an increase in systolic blood pressure over 160/95 mm Hg, fatigue, headache.

Patient I., 14 years old. Diagnosis: grade I arterial hypertension, was in the pediatric ward from 04/07/2004 to 04/19/2004. Complaints of weakness, increased blood pressure over 140/90 mmHg, headache, decreased attention, memory.

Table
Blood flow indicators (speeds and corresponding indices) in the control and experiment group A patient Vessel S, cm / c M, cm / s D, cm / c PI S / d Ri control (patient C) a. radialis 1 63 fifteen 9 3.57 7.25 0.86 a. radialis 2 79 25 12 2.67 6.47 0.85 experiment (patient A) a. radialis 1 52 19 8 2.27 6.37 0.84 a. radialis 2 one hundred 23 13 3.76 8.02 0.88 experiment (patient And) a. radialis 1 45 17 10 2.00 4.32 0.77 a. radialis 2 82 23 fourteen 2.88 5.77 0.83

The table shows the data obtained during the study: 1 - baseline, 2 - against the background of reactive hyperemia. Speeds: S - systolic (peak), M - medium, D - diastolic; indices: PI - pulsative, S / D - systolodiastolic, RI - resistive. PI = S-D / M, RI = S-D / S.

Thus, when using the proposed method revealed: a combination of the increase in peak speed almost 2 times and a significant increase in the pulsative index in comparison with the control group.

A method for the diagnosis of endothelial dysfunction in adolescents with arterial hypertension was studied in 32 patients with a diagnosis of arterial hypertension. In all cases, this type of study allowed a better diagnosis of this disease and was an additional objective criterion in terms of stratification by risk groups. The method will allow for more effective correction of high blood pressure, which will significantly reduce the length of hospitalization and financial costs for treatment.

Information sources

1. Zateyshchikova A.A., Zateyshchikov D.A. "Endothelial regulation of vascular tone: research methods and clinical significance" "Cardiology", 1998, No. 9, p. 71.

2. Ivanova O. V., Rogoza A. N., Balakhonova T. V. "Determining the sensitivity of the brachial artery to shear stress on the endothelium as a method for assessing the state of endothelium-dependent vasodilation using high-resolution ultrasound in patients with arterial hypertension" "Cardiology", 1998, No. 3, pp. 37-41 - prototype.

Claims (1)

A method for diagnosing endothelial dysfunction in adolescents with arterial hypertension, including determining the systolic blood flow velocity, applying a cuff of the sphygmomanometer and increasing the pressure in it by 50 mm Hg higher than systolic blood pressure, characterized in that the pulsative index is additionally determined, while the radial artery is located 3-5 cm distal to the wrist joint, the pressure in the cuff is kept inflated for 30 s, the speed parameters of the blood flow of the first compensatory wave are determined, and if an increase is detected systolic velocity in combination with an increase in the pulsatile index compared with the control group diagnose endothelial dysfunction.