A circuit for processing abnormal leads of dynamic electrocardiograph recorder

Abstract

The invention discloses a lead abnormality processing circuit for a dynamic electrocardiograph recorder, comprising a dynamic electrocardiograph recorder, a lead-off detection device, an electrocardiograph amplifying and filtering circuit, an N lead-off detection circuit, a spare right foot driving voltage switching circuit to a C3 lead circuit and an R / L lead-off detection and switching circuit; the lead-off detection device adopts a direct current detection lead-off mode; the polarization protection voltage of the electrocardiograph amplifying and filtering circuit is set to ±400mV; the spare right foot driving voltage is switched to the C3 lead circuit to achieve connection or disconnection with the spare right foot driving voltage through the lead-off detection device; the R / L lead-off detection and switching circuit achieves switching of the central potential through the lead-off detection device; the invention has strong anti-interference ability, can ensure the effectiveness of the entire dynamic electrocardiograph examination, will not affect clinical condition analysis and diagnosis, and saves time for doctors and patients.

Description

Technical Field

[0001] The invention relates to the technical field of dynamic electrocardiograph recorders, in particular to a circuit for processing abnormal leads of dynamic electrocardiograph recorders. Background Art

[0002] A dynamic electrocardiogram recorder is a device that monitors the patient's ECG changes in daily life for a long time. It can be carried with the patient and continuously record the patient's ECG signals for more than 24 hours, and then send them to a computer for auxiliary analysis. It is one of the important means of clinically analyzing the condition, establishing diagnosis, and judging the efficacy of the treatment.

[0003] The dynamic ECG recorder is often interfered by various noises when it is carried on the human body. Among them, the more typical noises are baseline drift, electrode contact noise, power line interference, electrode detachment, myoelectric interference, etc. Medical engineers use different processing methods for various noise signals with different sources and characteristics. In the dynamic ECG lead system, for example, there are 10 wires R, L, F, N, C1, C2, C3, C4, C5, and C6 in the 12-lead standard system, among which N does not participate in the collection. Medical engineers provide a driving signal to the human body through N, which improves the anti-interference ability of the entire ECG collection and amplification circuit, and plays a key role in suppressing baseline drift, electrode contact noise, power line interference, etc.

[0004] When the device is carried around, the following situations may occur, causing abnormal leads: 1) The movement or pulling of the human body may cause the lead wire to fall off or have poor contact; 2) The disposable electrodes used in the hospital are placed for too long, and the conductive glue dries and loses its stickiness, resulting in poor contact; 3) In the summer, when the human body is overheated and sweats, the conductive glue of some electrodes loses its stickiness after contacting with sweat, which can also cause poor contact of the electrodes; 4) A wire of the lead wire is damaged, resulting in abnormal signals. All of the above situations occur during the actual use of the dynamic ECG recorder, and it is difficult to avoid them. Once this happens, the patient is unable to judge the condition of the lead. Therefore, it is often the case that after the dynamic ECG recorder has collected data for 24 hours, the data is played back through the computer, and it is found that the collected waveforms are all noise and cannot be analyzed. At this time, the user can only let the patient test for another 24 hours, which will waste the time of doctors and patients, and even cause serious non-cooperation of patients.

[0005] According to the investigation and summary, when the leads of the Holter recorder are abnormal, the probability of a wire falling off is relatively high. The main significance of the Holter examination is to determine the patient's arrhythmia, discover potential factors of sudden death, diagnose ischemic heart disease, and detect the operating status of workers' pacemakers. If only one wire falls off, the abnormalities of the leads in different positions can be handled to ensure the effectiveness of the entire Holter examination. It will not affect the clinical condition analysis and diagnosis, and the patient does not need to undergo another Holter test, which saves time for doctors and patients and helps to ease the doctor-patient relationship. Summary of the invention

[0006] The purpose of the present invention is to provide a Holter recorder lead abnormality processing circuit which has strong anti-interference ability, can ensure the effectiveness of the entire dynamic electrocardiogram examination, will not affect clinical condition analysis and diagnosis, saves time for doctors and patients, and is conducive to easing doctor-patient relationship.

[0007] The present invention is achieved through the following technical solutions:

[0008] A circuit for processing abnormal leads of a dynamic electrocardiogram recorder, comprising:

[0009] A dynamic electrocardiograph, wherein the dynamic electrocardiograph is used to collect electrocardiograph waveforms;

[0010] A lead-off detection device, the lead-off detection device is electrically connected to the Holter recorder; the lead-off detection device uses a direct current to detect lead-off;

[0011] An ECG amplifying and filtering circuit, the ECG amplifying and filtering circuit being electrically connected to the lead-off detection device; the polarization protection voltage of the ECG amplifying and filtering circuit being set to ±400mV;

[0012] An N-lead off detection circuit, the N-lead off detection circuit is electrically connected to the lead off detection device; the lead N output DC voltage of the N-lead off detection circuit is set to VCC / 2;

[0013] The standby right foot driving voltage is switched to the C3 lead circuit, and the standby right foot driving voltage is switched to the C3 lead circuit to achieve connection or disconnection with the standby right foot driving voltage through the lead-off detection device;

[0014] An R / L lead-off detection and switching circuit realizes the switching of the central potential through the lead-off detection device.

[0015] Furthermore, the lead-off detection device includes a single-chip microcomputer, an analog-to-digital converter and an operational amplifier; the single-chip microcomputer is electrically connected to the analog-to-digital converter and the operational amplifier, respectively.

[0016] Furthermore, the circuit for switching the standby right foot driving voltage to lead C3 includes lead C3 and a first control switch; the first control switch is electrically connected to the single-chip microcomputer; the N lead-off detection circuit determines that the N lead is off; the single-chip microcomputer controls the first control switch to connect the standby right foot driving voltage to lead C3; the N lead-off detection circuit determines that the N lead is reconnected and then cuts off the connection between the standby right foot driving voltage and lead C3, and the lead C3 is connected to the positive input end of the ECG amplification and filtering circuit.

[0017] Furthermore, the R / L lead-off detection and switching circuit includes lead R, lead L and a second control switch; the second control switch is electrically connected to the single-chip microcomputer; when lead R is off, after the single-chip microcomputer determines that lead R is off, the single-chip microcomputer controls the second control switch to switch the emitter-follower circuit of lead L to the emitter-follower circuit output end of lead R; when lead R is in good contact again, the single-chip microcomputer determines that lead R is connected, and switches the central potential point from lead L to lead R.

[0018] Furthermore, the positive input terminal of the ECG amplifying and filtering circuit is connected to a pull-down resistor and is connected to a spare right foot driving voltage; the negative input terminal and the output terminal of the ECG amplifying and filtering circuit are connected.

[0019] Furthermore, the ECG signals of the leads R, L, F, C1, C2, C3, C4, C5, and C6 of the dynamic electrocardiograph are superimposed on VCC / 2; and the lead N is connected in series with a first resistor.

[0020] Furthermore, the standby right foot driving voltage is connected in series with a second resistor and connected to the lead C3.

[0021] Furthermore, the DC voltage of the standby right foot driving voltage is VCC / 2-0.35V.

[0022] Furthermore, the resistance of the pull-down resistor is 44 MΩ.

[0023] Furthermore, the resistance value of the first resistor is 10KΩ; the resistance value of the second resistor is 200KΩ.

[0024] Beneficial effects of the present invention:

[0025] 1. The dynamic electrocardiograph is not suitable for the AC lead-off detection method due to its small size. The present invention adopts the DC lead-off detection method, and few components are added to the circuit.

[0026] 2. The front end of the ECG amplification circuit in the prior art is generally pulled up or pulled down to VCC or GND. When an abnormality such as lead falling off occurs, the operational amplifier will be saturated. When lead N falls off, all leads will be saturated, and ECG waveforms cannot be collected. The polarization protection voltage of the ECG amplification filter circuit of the dynamic ECG recorder of the present invention is increased from ±300mV to ±400mV, and the front end of the ECG amplification circuit is connected to the spare right foot drive voltage with a pull-down resistor of 44MΩ. The DC voltage of the spare right foot drive voltage is VCC / 2-0.35V, and the operational amplifier saturation phenomenon will not occur. When lead N falls off, the dynamic ECG recorder can still collect ECG waveforms.

[0027] 3. When the single chip microcomputer determines that the lead N is abnormally detached, the single chip microcomputer controls the first control switch to connect the spare right foot driving voltage VCC / 2-0.35V in series with the second resistor with a resistance of 200KΩ to the lead C3. After the human body obtains the DC driving voltage, the anti-interference ability of the dynamic electrocardiograph recorder is restored, further improving the anti-interference ability of the dynamic electrocardiograph recorder.

[0028] 4. After the MCU determines that the lead N is reattached, the MCU will control the first control switch to cut off the connection between the standby right foot drive voltage VCC / 2-0.35V and lead C3, and lead N will be used as the right foot drive electrode again. The dynamic ECG recorder can continue to collect ECG waveforms.

[0029] 5. The present invention does not use the front-end circuit based on the Wilson equilateral triangle resistor network, and takes the lead R as the central potential. When the lead R is off, the single-chip microcomputer determines that it is off, and switches the lead L emitter-follower circuit to the emitter-follower circuit output end of the lead R, so that the central potential of all leads becomes L, thereby ensuring that some ECG lead signals are normal. When the lead R is well contacted again, the single-chip microcomputer determines that the lead R is connected, and switches the central potential point from the lead L to the lead R, ensuring that the ECG lead signal is normal. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 This is a schematic diagram of the structure of the R lead-off detection circuit according to an embodiment of the present invention;

[0031] Figure 2 This is a schematic diagram of the structure of an N-lead-off detection circuit according to an embodiment of the present invention;

[0032] Figure 3 This is a schematic diagram of the circuit structure in which the standby right foot driving voltage is switched to lead C3 according to an embodiment of the present invention;

[0033] Figure 4 Schematic diagram of the structure of the R / L lead-off detection and switching circuit according to an embodiment of the present invention;

[0034] Figure 5This is a human body dynamic lead diagram according to an embodiment of the present invention. DETAILED DESCRIPTION

[0035] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. The exemplary embodiments and descriptions of the present invention are used to explain the present invention, but are not intended to limit the present invention.

[0036] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back, upper end, lower end, top, bottom...) are only used to explain the relative position relationship, movement status, etc. between the components in a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0037] In the present invention, unless otherwise clearly defined and limited, the term "connection" should be understood in a broad sense, for example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0038] In addition, in the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features; in addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0039] like Figures 1 to 5 As shown, a circuit for processing abnormal leads of a dynamic electrocardiogram recorder comprises:

[0040] A dynamic electrocardiograph, wherein the dynamic electrocardiograph is used to collect electrocardiograph waveforms;

[0041] A lead-off detection device, the lead-off detection device is electrically connected to the Holter recorder; the lead-off detection device uses a direct current to detect lead-off;

[0042] An ECG amplifying and filtering circuit, the ECG amplifying and filtering circuit is electrically connected to the lead-off detection device; the polarization protection voltage of the ECG amplifying and filtering circuit is set to ±400mV; it should be noted that the polarization protection voltage of the ECG amplifying and filtering circuit of the dynamic ECG recorder is increased from ±300mV to ±400mV, so that when the operational amplifier used in the ECG amplifying and filtering circuit has a polarization voltage of ±350mV, the operational amplifier does not experience saturation amplification.

[0043] An N-lead off detection circuit, the N-lead off detection circuit is electrically connected to the lead off detection device; the lead N output DC voltage of the N-lead off detection circuit is set to VCC / 2;

[0044] The standby right foot driving voltage is switched to the C3 lead circuit, and the standby right foot driving voltage is switched to the C3 lead circuit to achieve connection or disconnection with the standby right foot driving voltage through the lead-off detection device;

[0045] An R / L lead-off detection and switching circuit realizes the switching of the central potential through the lead-off detection device.

[0046] Specifically, in this embodiment, the ECG signals of the leads R, L, F, C1, C2, C3, C4, C5, and C6 of the dynamic electrocardiograph are superimposed on VCC / 2; and the lead N is connected in series with a first resistor.

[0047] Specifically, in this embodiment, the lead-off detection device includes a single-chip microcomputer, an analog-to-digital converter and an operational amplifier; the single-chip microcomputer is electrically connected to the analog-to-digital converter and the operational amplifier, respectively.

[0048] refer to Figure 2 It should be noted that the method for judging the fall-off of lead N is as follows: lead N is also called the right foot driving electrode. In the present invention, the output DC voltage of lead N is VCC / 2. The ECG signals of the wires R, L, F, C1, C2, C3, C4, C5, and C6 will be superimposed on VCC / 2. Due to the polarization voltage of the ECG electrode sheet, the signal appearing at the input end of the operational amplifier used in the ECG amplification and filtering circuit is within VCC / 2±300mV. When lead N falls off abnormally, the single-chip computer will judge that all other leads have fallen off. At this time, there are two possibilities: 1) at least lead N is in an abnormal state of falling off; 2) lead N is normal, and all other leads are off. For the second case, all lead signals are interference, and there is no collection significance. In addition, the first case should be more likely to occur, so the single-chip computer judges that lead N is in an abnormal state of falling off through all lead falling off.

[0049] refer to Figure 3Specifically, in this embodiment, the circuit for switching the standby right foot driving voltage to lead C3 includes lead C3 and a first control switch; the first control switch is electrically connected to the single-chip microcomputer; the N lead-off detection circuit determines that the N lead is off; the single-chip microcomputer controls the first control switch to connect the standby right foot driving voltage to lead C3; the N lead-off detection circuit determines that the N lead is reconnected and then cuts off the connection between the standby right foot driving voltage and lead C3, and the lead C3 is connected to the positive input end of the ECG amplification and filtering circuit.

[0050] Specifically, in this embodiment, the DC voltage of the standby right foot driving voltage is VCC / 2-0.35V.

[0051] Specifically, in this embodiment, the resistance value of the first resistor is 10KΩ; the resistance value of the second resistor is 200KΩ.

[0052] It should be noted that when the single-chip computer determines that lead N is abnormally off, the ECG signals of leads R, L, F, C1, C2, C3, C4, C5, and C6 will be superimposed on VCC / 2-0.35V, and the dynamic ECG recorder will also collect ECG waveforms. However, due to the off-set of lead N, the interferences such as baseline drift, electrode contact noise, and power line interference will be very large, so it is necessary to re-provide the driving DC voltage through other leads with relatively low clinical diagnostic significance. The single-chip computer controls the first control switch to connect the second resistor with a series resistance of 200KΩ to the standby right foot driving voltage VCC / 2-0.35V to lead C3, which is connected to the positive input end of the ECG amplifier circuit, and the negative input end and output end of the ECG amplifier filter circuit are connected, playing the role of a voltage follower. After the human body receives the DC driving voltage, the anti-interference ability of the dynamic ECG recorder is restored. Other existing products do not have this design.

[0053] Method for judging that lead N is reattached: the DC driving voltage VCC / 2-0.35V is connected in series with the second resistor with a resistance of 200KΩ to lead C3. When lead N is in good contact again, the DC voltage of lead N is VCC / 2, and the series resistor is only the first resistor with a resistance of 10KΩ. The human body impedance is less than 10KΩ after passing through the electrode conductive liquid. Then the voltage appearing in other leads is within VCC / 2±300mV, and the single-chip microcomputer can judge that lead N is attached. When it is judged that lead N is reattached, the single-chip microcomputer controls the first control switch to cut off the connection between the standby right foot driving voltage VCC / 2-0.35V and lead C3.

[0054] refer to Figure 4Specifically, in the present embodiment, the R / L lead-off detection and switching circuit includes lead R, lead L and a second control switch; the second control switch is electrically connected to the single-chip microcomputer; when lead R is off, the single-chip microcomputer determines that lead R is off, and the single-chip microcomputer controls the second control switch to switch the lead L emitter-follower circuit to the emitter-follower circuit output end of lead R; when lead R is in good contact again, the single-chip microcomputer determines that lead R is connected, and switches the central potential point from lead L to lead R. It should be noted that the present invention does not adopt a front-end circuit based on a Wilson equilateral triangle resistor network, and takes lead R as the central potential. When lead R is off, the single-chip microcomputer determines that it is off, and switches the lead L emitter-follower circuit to the emitter-follower circuit output end of lead R, so that the central potential of all leads becomes L, thereby ensuring that some ECG lead signals are normal. When lead R is in good contact again, the single-chip microcomputer determines that lead R is connected, and switches the central potential point from lead L to lead R.

[0055] Specifically, in this embodiment, the positive input terminal of the ECG amplifying and filtering circuit is connected to a pull-down resistor and to a standby right foot driving voltage; the negative input terminal of the ECG amplifying and filtering circuit is connected to the output terminal. It should be noted that the negative input terminal of the ECG amplifying and filtering circuit is connected to the output terminal, playing the role of a voltage follower.

[0056] Specifically, in this embodiment, the standby right foot driving voltage is connected in series with a second resistor and connected to the lead C3.

[0057] refer to Figure 1 Specifically, in the present embodiment, the pull-down resistor has a resistance of 44MΩ. It should be noted that, a DC detection lead-off method is adopted, and a pull-down resistor with a resistance of 44MΩ is connected to the front end of the ECG amplification and filtering circuit, and is connected to the spare right foot drive voltage. The pull-down DC voltage is VCC / 2-0.35V. When an abnormality such as lead-off occurs, the voltage at the output of the operational amplifier is VCC / 2-0.35V. The voltage value is collected by the analog-to-digital converter, and the single-chip computer determines that the line is off through digital comparison. The DC voltage is not used as VCC or ground in order to ensure that the operational amplifier used in the ECG amplification and filtering circuit does not have saturated amplification. At the same time, because it is higher than the polarization protection voltage of ±300mV, when the polarization protection voltage of ±300mV occurs, it is guaranteed not to be misreported as a lead abnormality.

[0058] The present invention adopts a direct current detection method for lead shedding, and few components are added to the circuit. The technical problem that the dynamic electrocardiograph recorder is not suitable for the AC shedding detection method due to its small size is solved; the front end of the prior art electrocardiograph amplification circuit is generally pulled up or pulled down to VCC or GND, and when an abnormality such as lead shedding occurs, its operational amplifier will experience amplifier saturation. When lead N falls off, all leads will experience amplifier saturation, and the electrocardiograph waveform cannot be collected. The polarization protection voltage of the electrocardiograph amplification filter circuit of the dynamic electrocardiograph recorder of the present invention is increased from ±300mV to ±400mV, and the front end of the electrocardiograph amplification circuit is connected to a pull-down 44MΩ resistor to the spare right foot drive voltage. The DC voltage of the spare right foot drive voltage is VCC / 2-0.35V, and amplifier saturation will not occur. When lead N falls off, the dynamic electrocardiograph recorder can still collect the electrocardiograph waveform.

[0059] In the present invention, when the single-chip microcomputer determines that the lead N is abnormally detached, the single-chip microcomputer controls the first control switch to connect the spare right foot driving voltage VCC / 2-0.35V in series with the second resistor with a resistance of 200KΩ to the lead C3. After the human body obtains the DC driving voltage, the anti-interference ability of the dynamic electrocardiograph recorder is restored, further improving the anti-interference ability of the dynamic electrocardiograph recorder. After the single-chip microcomputer determines that the lead N is reattached, the single-chip microcomputer controls the first control switch to cut off the spare right foot driving voltage VCC / 2-0.35V from the connection with the lead C3, and the lead N is used as the right foot driving electrode again. The dynamic electrocardiograph recorder can continue to collect electrocardiogram waveforms.

[0060] The present invention does not use the front-end circuit based on the Wilson equilateral triangle resistor network, and takes the lead R as the central potential. When the lead R is off, the single chip microcomputer judges that it is off, and switches the lead L emitter-follower circuit to the emitter-follower circuit output end of the lead R, so that the central potential of all leads becomes L, thereby ensuring that some ECG lead signals are normal. When the lead R is well contacted again, the single chip microcomputer judges that the lead R is connected, and switches the central potential point from the lead L to the lead R, ensuring that the ECG lead signal is normal.

[0061] The technical solutions provided by the embodiments of the present invention are introduced in detail above. Specific examples are used herein to illustrate the principles and implementation methods of the embodiments of the present invention. The description of the above embodiments is only applicable to help understand the principles of the embodiments of the present invention. At the same time, for those skilled in the art, according to the embodiments of the present invention, there will be changes in the specific implementation methods and application scopes. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A circuit for processing abnormal leads of a dynamic electrocardiogram recorder, characterized in that: include: A dynamic electrocardiograph, wherein the dynamic electrocardiograph is used to collect electrocardiograph waveforms; A lead-off detection device, the lead-off detection device is electrically connected to the Holter recorder; the lead-off detection device uses a direct current to detect lead-off; An ECG amplifying and filtering circuit, the ECG amplifying and filtering circuit being electrically connected to the lead-off detection device; the polarization protection voltage of the ECG amplifying and filtering circuit being set to ±400mV; An N-lead off detection circuit, the N-lead off detection circuit is electrically connected to the lead off detection device; the lead N output DC voltage of the N-lead off detection circuit is set to VCC / 2; The standby right foot driving voltage is switched to the C3 lead circuit, and the standby right foot driving voltage is switched to the C3 lead circuit to achieve connection or disconnection with the standby right foot driving voltage through the lead-off detection device; An R / L lead-off detection and switching circuit realizes the switching of the central potential through the lead-off detection device.

2. The lead abnormality processing circuit of a dynamic electrocardiogram recorder according to claim 1, characterized in that: The lead-off detection device comprises a single-chip microcomputer, an analog-to-digital converter and an operational amplifier; the single-chip microcomputer is electrically connected to the analog-to-digital converter and the operational amplifier respectively.

3. The circuit for processing abnormal leads of a dynamic electrocardiogram recorder according to claim 2, characterized in that: The circuit for switching the standby right foot driving voltage to lead C3 includes lead C3 and a first control switch; the first control switch is electrically connected to the single-chip microcomputer; the N lead-off detection circuit determines that the N lead is off, and the single-chip microcomputer controls the first control switch to connect the standby right foot driving voltage to lead C3; the N lead-off detection circuit determines that the N lead is reconnected and then cuts off the connection between the standby right foot driving voltage and lead C3, and the lead C3 is connected to the positive input end of the electrocardiogram amplification and filtering circuit.

4. The circuit for processing abnormal leads of a dynamic electrocardiogram recorder according to claim 2, characterized in that: The R / L lead-off detection and switching circuit includes lead R, lead L and a second control switch; the second control switch is electrically connected to the single-chip microcomputer; when lead R is off, after the single-chip microcomputer determines that lead R is off, the single-chip microcomputer controls the second control switch to switch the emitter-follower circuit of lead L to the emitter-follower circuit output end of lead R; when lead R is in good contact again, the single-chip microcomputer determines that lead R is connected, and switches the central potential point from lead L to lead R.

5. The lead abnormality processing circuit of a dynamic electrocardiogram recorder according to claim 4, characterized in that: The positive input end of the electrocardiogram amplifying and filtering circuit is connected to a pull-down resistor and is also connected to a spare right foot driving voltage; the negative input end of the electrocardiogram amplifying and filtering circuit is connected to an output end.

6. A circuit for processing abnormal leads of a dynamic electrocardiogram recorder according to claim 5, characterized in that: The ECG signals of the wires R, L, F, C1, C2, C3, C4, C5 and C6 of the dynamic electrocardiograph are superimposed on VCC / 2; the lead N is connected in series with a first resistor.

7. A circuit for processing abnormal leads of a dynamic electrocardiogram recorder according to claim 6, characterized in that: The standby right foot drive voltage is connected to the lead C3 in series with a second resistor.

8. The lead abnormality processing circuit of a dynamic electrocardiogram recorder according to claim 1, characterized in that: The DC voltage of the standby right foot driving voltage is VCC / 2-0.35V.

9. The circuit for processing abnormal leads of a dynamic electrocardiogram recorder according to claim 5, characterized in that: The resistance of the pull-down resistor is 44 MΩ.

10. The lead abnormality processing circuit of a dynamic electrocardiogram recorder according to claim 7, characterized in that: The resistance value of the first resistor is 10KΩ; the resistance value of the second resistor is 200KΩ.

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