SU1367936A1 - Apparatus for investigating vascular tension - Google Patents

Abstract

The invention permits the determination of vascular tone of the arteries of the muscular type and can be used in the diagnosis of endoarteritis, osteomyelitis, scoliosis and other diseases associated with disorders of the vascular system. Vascular tone fluctuations are characterized by the time difference between the propagation of a pulse wave in adjacent cardiac cycles. The propagation time of the pulse wave is measured between the R-wave of the cardiosignal and the falling edge of the differentiated rheosignal. Consequently, the process of forming the measurement interval captures the phase of slow blood vessel filling, which is less dependent on factors of heart activity and due to the elastic properties of medium caliber vessels, which increases the reliability of the study of vascular tone fluctuations. The device contains amplifiers of cardiosignals and rheosignals with electrodes, a differentiation unit, two pulse shapers, a clock generator, two delay elements, a pulse counter, a subtractor, two memory blocks, a digital-to-threshold converter, a recorder, and an indicator. On the chart tape of the recorder, the time of propagation of the pulse wave in each cycle of heart activity is recorded in the form of a stepwise curve, and on the indicator board the difference in the times of propagation of the pulse wave in adjacent cycles is displayed. 2 Il. W oo od with oq od

Description

The invention relates to medical technology and can be used in studies of the cardiovascular system to determine the tone of muscular arteries for diagnostic purposes.

The aim of the invention is to increase the reliability of determining the fluctuations of the vascular tone by measuring the time of propagation of a pulse wave relative to the posterior front of a differentiated rheosignal.

Figure 1 shows the functional diagram of the device; Fig. 2 shows diagrams illustrating its operation.

The device contains electrodes 1

the pulse shaper 5 pulses on the R-wave ECG, then in the memory block 5 contains, the code of the propagation time

pulse wave in the previous cycle of heart activity. This code is converted into a voltage by a digital-to-analog converter 16, which is recorded on the chart tape of the recorder 17. At the same time, the code from the output of memory block 12 is fed to the second input of subtraction unit 13, the output of which is the code for the difference of the propagation time of the pulse wave in this and the preceding cycles of heart activity. This code enters the information input of the second memory block 14. The write command is given by the delayed element 9

and 2, amplifier 3 cardiosignals, 20 psi delay for 3-5 µs output pulse

4 pulse signal generator, pulse shaper 5 on ECG R-wave, differentiation unit 6, pulse shaper 7, clock generator 8, delay elements 9 and 10, pulse counter 11, first memory block 12, subtraction block 13, second memory block 14 , indicator 15, digital-to-analog converter 16 and recorder 17.,

The device works as follows.

The ECG signal amplified by an amplifier of 3 cardiosignals is fed to a shaper of 5 pulses via an R-wave ECG, the output of which starts the clock generator 8, and the pulse counter 11 starts recalculation of the pulses coming to it from the clock generator output. C signal

the output of amplifier 4 of re-signaling of the propagation pulse differential 40 is optimized in the differentiation unit b and fed to the input of the pulse former 7, the output of which produces a pulse corresponding to the falling edge of the differentiated re-signal. This pulse arrives at the stop input of the clock generator 8, as a result of which the clock generator is turned off, and in the pulse counter 11 a number is recorded that corresponds to a pulse wave propagation time in the current heart rate cycle on a certain time scale. Output

11 pulse counters are connected to the first vessels. The phase of the slow field input of the block 13 for the subtraction and information of the vessels (section II in FIG. 2, a) by the input of the first block 12 is less dependent on heart rate. Since the command for recording factors and, to a greater degree, training in the memory block 12, give the output imprinted by the elastic properties of the vessels.

shaper 7 pulses. The code from the output of the memory block 14 is indicated by a digital indicator 15. The pulse counter 11 is reset by you.

the driving pulse of the driver 5 pulses, delayed by 3-5 μs in the element 10 delay.

Thus, in the proposed device, on the chart tape of the recorder 17 is recorded as a stepwise curve of the change in the propagation time of the pulse wave in each cycle of cardiac activity, and the indicator 15 shows the difference

the propagation times of the pulse wave between the current and previous cycles of heart activity, taking into account the sign (+ -),

The feasibility of determining the time on the falling edge of a differentiated reosignal is caused by the following considerations. Usually, vascular tone fluctuations are determined

by measuring the time between the R-tooth ECG and the leading edge of the rheosignal at half its maximum value, which corresponds to the phase of rapid filling of vessels (section I in FIG. 2, a). At the same time, the steepness of the front in the phase of fast blood filling of vessels due to the stroke volume of the heart and directly depends on the elastic modulus of the walls of a large caliber. The boundary of the zones of fast and slow filling of the vessels corresponds to the inflection point of the resignal, i.e. the maximum of the differentiated reosignal (figure 2, b). In this connection, measuring the time of pulse wave propagation along the trailing edge of a differentiated rhosignal allows you to more accurately and reliably study the vibrations of the vascular tone of medium caliber arteries due to the guaranteed capture of the zone of slow filling of vessels (figure 2, the pulse at the output of the former 7 is shown) .

Claims (1)

Invention Formula A device for examining vascular tone, containing serially connected cardio signal amplifiers with electrodes and a pulse shaper on an R-wave ECG, the output of which is connected to the trigger input of a clock generator, a amplifier of rheosignals with electrodes, a pulse shaper, the output of which is connected to the stop input of the clock generator, the output of which is connected to the counting input of the pulse counter, the recorder, five five By the fact that, in order to increase the reliability of determining the fluctuations of the vascular tone by measuring the pulse propagation time, relative to the trailing edge of the differentiated rheosignal, the sequentially installed subtraction unit, the first input of which is connected to the output of the pulse counter, is additionally inserted into it and a display unit, a differentiation unit connected between a rheosignal amplifier and a driver — pulses, two delay elements, a second memory block and a digital-analog signal the converter, with the first delay element set between the output of the pulse generator and the recording input of the first memory block, the information input of the second memory block is connected to the output of the counter, and the recording input is connected to the output of the pulse shaper on the ECG R-wave, to which the input is also connected The second delay element, the output of which is connected to the reset input of the pulse counter, the output of the second memory block is connected to the second input of the subtractor and the input of the digital-to-analog converter, the output of which is connected to the register pv. fig / ig.2