KR102049598B1 - Implantable impedance measurement devices and heart failure monitoring system using it - Google Patents

Abstract

Heart failure monitoring system according to the present invention is inserted into the subcutaneous of the heart failure patient inserted implantable bioimpedance measuring device for wirelessly transmitting bioimpedance measurement information measuring the bioimpedance of the subcutaneous tissue; A database for recording heart failure monitoring information; And a service server that receives the bioimpedance measurement information and records the heart failure monitoring information of the database.

Description

Implantable bioimpedance measuring device and heart failure monitoring system using same {IMPLANTABLE IMPEDANCE MEASUREMENT DEVICES AND HEART FAILURE MONITORING SYSTEM USING IT}

The present invention relates to a bio-monitoring technology, and more particularly, to an implantable impedance measuring apparatus for measuring the bioimpedance of the subcutaneous tissue by inserting it into the subcutaneous tissue of a heart failure patient and a heart failure monitoring system that can be remotely monitored using the same. will be.

Heart failure refers to the inability to provide an adequate amount of blood from the heart to the whole body. This directly implies a decrease in cardiac contractility, but may broadly include a decrease in cardiac relaxation. Reduction in contractile function is due to necrosis and reduction of cardiomyocytes, resulting in insufficiency of blood supply due to contraction of cardiomyocytes. If not.

Heart failure continues to increase with rapid aging and lifestyle-related chronic diseases (hypertension, diabetes, hyperlipidemia), and it is emerging as a leading cause of death in Korea. As the fastest growing trend.

This is the final complication of coronary artery disease, hypertension, valve disease, cardiomyopathy, etc., and due to frequent insufficiency of other organs such as kidneys, medical expenses are high and intensive care is increased due to the increase of hospital stay and re-admission rate in elderly patients. This is necessary for severe chronic disease.

Prevalence increased rapidly with age, accounting for 9.3% of males in the 60s and 70s, 4.8% in females, 13.8% in males over 80s, and 12.2% in females. Known as

In countries with a large population of senior citizens, such as Europe, more than one in ten older adults have been reported to have heart failure.

Around 26 million people suffer from heart failure worldwide, and the number of heart failure patients continues to grow.

In Korea, the elderly population is expected to account for 25% of the total population in 2030. As the aging population grows faster, heart failure is expected to emerge as a social problem.

The most important in the diagnosis of heart failure described above is the patient side symptoms. The main symptom of heart failure is shortness of breath, which is a subjective symptom of shortness of breath due to the lack of adequate blood for activity. As the disease accelerates and becomes more chronic, dyspnea occurs even during periods of inactivity.

In addition to dyspnea, objective medical findings appear, most commonly pulmonary edema. Pulmonary vein pressure is increased due to inadequate blood supply due to a decrease in contractile function, and pulmonary edema occurs in severe cases accompanied by findings of right heart failure.

In addition to these symptoms and findings, the role of echocardiography is important. Decreased contractile function in echocardiography can be confirmed, and the hematologic test is NT-proBNP (N-terminal pro B-type Natriuretic Peptide).

In the early stages of heart failure, the main treatment is drug treatment, which adds myocardial protective drugs around diuretics because systemic edema and respiratory distress occur due to a decrease in myocardial contractile function. You will insert an implantable synchronization machine in your body and you will eventually have a heart transplant.

The reason why such a heart failure is a serious disease is that the mortality rate is high and the treatment cost is high.

The total medical expenses that a patient spends for one year from the above-mentioned heart failure treatment were about 6.97 million won, and hospitalization cost was about 6.66 million won, which was about 95% of the total cost. The average length of hospital stay per hospital stay was about 10 days, and the average hospitalization cost was about 5 million won, suggesting a significant economic burden from hospitalization of patients with heart failure. This is much higher than the average hospitalization cost of 2.16 million won for lung cancer, one of the most expensive cancers. In addition, 3 to 4 out of 10 heart failure patients (37.4%) are hospitalized within a year.

In developed countries, more than 20 million people are suffering from heart failure worldwide as a major cause of hospitalization for people age 65 and older. In addition, as a limitation of daily activities, it is reported to have a greater influence on the quality of life of patients than chronic diseases such as arthritis and chronic lung disease.

Heart failure has been increasing rapidly with aging, and the number of heart failure patients and medical expenses have increased year by year, and the number of patients with heart failure in Korea for the last five years (2010-2014) is about 9,000 to 11,9000, about 20. The percentage of total medical expenses increased by 38%, from KRW 58.5 billion to KRW 80.8 billion.

Therefore, there has been a need for the development of a technology that enables to monitor the condition of a heart failure patient.

More specifically, water measurement plays a very important role in patients with diseases that require fluid management in the body, such as heart failure or dialysis patients. In the past, techniques have been proposed to implement accurate and reliable monitoring of blood supply status, diuresis, dialysis, ultrafiltration, and fluid overload during pharmacological intervention through bioimpedance of subcutaneous tissue of a patient. Especially in the case of heart failure patients, the effect was confirmed through prospective studies, and it is given priority to patients with acute failure symptoms. This provides an opportunity for diagnosis, contributing to avoiding hospitalization and reducing the corresponding mortality rate.

Therefore, in the related art, the development of a technology for easily monitoring the condition of a heart failure patient by monitoring the bioimpedance of the subcutaneous tissue of the heart failure patient has been required.

Korea Patent Registration No. 10-1231240 Republic of Korea Patent Registration No. 10-1345640 Korea Patent Registration No. 10-1492802 Republic of Korea Patent Application No. 10-2015-0086994

It is an object of the present invention to provide an implantable impedance measuring apparatus for measuring the bioimpedance of the subcutaneous tissue by inserting it into the subcutaneous tissue of the heart failure patient and a heart failure monitoring system that can remotely monitor the information of the heart failure patient. .

Heart failure monitoring system for monitoring heart failure through the implantable bioimpedance measurement according to the present invention for achieving the above object, is inserted into the subcutaneous of the heart failure patient to wirelessly transmit the bioimpedance measurement information measuring the bioimpedance of the subcutaneous tissue Insertion type bioimpedance measuring device; A database for recording heart failure monitoring information; And a service server that receives the bioimpedance measurement information and records the heart failure monitoring information of the database.

The present invention produces the effect of enabling effective monitoring of heart failure patients by measuring and remotely transmitting the bioimpedance of the patient's subcutaneous tissue for monitoring heart failure patients.

1 illustrates an implantable bioimpedance sensor in accordance with a preferred embodiment of the present invention.
2 is a cross-sectional view of the implantable bioimpedance sensor according to a preferred embodiment of the present invention.
3 is a block diagram of an implantable bioimpedance measuring device according to a preferred embodiment of the present invention.
4 is a view illustrating a manufacturing process of an implantable bioimpedance sensor according to a preferred embodiment of the present invention.
5 is a block diagram of a heart failure monitoring system having an implantable bioimpedance measuring device according to a preferred embodiment of the present invention.
6 is a view showing an example of mounting the inserted biometric impedance sensor according to a preferred embodiment of the present invention.
7 is a procedure of the heart failure monitoring method according to a preferred embodiment of the present invention.
8 shows tables showing the relationship between bioimpedance and heart failure status.

The present invention can enable effective monitoring of heart failure patients by measuring and remotely transmitting the bioimpedance of the subcutaneous tissue of the patient for monitoring the heart failure patients.

<Configuration of the implantable bioimpedance sensor>

Figure 1 illustrates an implantable bioimpedance sensor according to a preferred embodiment of the present invention, Figure 2 is a cross-sectional view of the implantable bioimpedance sensor in accordance with a preferred embodiment of the present invention.

1 and 2 will be described in detail the configuration and operation of the implantable bioimpedance measuring sensor according to a preferred embodiment of the present invention.

The implantable bioimpedance sensor measures the bioimpedance of the subcutaneous tissue. The implantable bioimpedance sensor is a Novel Planar Small Electrode Sensor (NPSES) having four pairs of electrodes 1001, 1002, 1021, 1022, 1041, 1042, 1061, and 1062. A current is applied to the subcutaneous tissue in contact with the electrodes through the electrodes to measure the bioimpedance of the subcutaneous tissue through the difference between the reference electrode and the measuring electrode.

The implantable bioimpedance measuring sensor includes a plurality of electrode pairs 1001, 1002, 1021, 1022, 1041, 1042, 1061, and 1062 which are spaced apart at regular intervals based on a center point of a Si substrate 200. An insulating layer (SiO ₂ ) 202 is disposed on the silicon substrate 200, and an adhesion layer (Cr) 204 is disposed on an upper surface of the insulating layer 202. The upper surface is formed of a structure in which an electrode layer (au) 206 made of gold is located.

The electrodes of the implantable bioimpedance sensor have a structure in which electrodes are arranged around a circle of a constant radius with respect to a center point, and the tracks of the sensor have a small electrode structure in which electrodes are arranged in a circle having a diameter of 2 mm.

The implantable bioimpedance measurement sensor measures the bioimpedance by sequentially applying current or voltage to each electrode pair, thereby measuring skin bioimpedance in all directions, such as vertical or horizontal, and calculating the average of the bioimpedance. In particular, the implantable bioimpedance sensor is supplied with a current of 50 frequencies from 5kHz to 1,000kHz for the measurement of the bioimpedance, the high-frequency current to measure the bioimpedance indicating the total body moisture, and the low-frequency current Enables measurement of bioimpedance indicating extracellular moisture.

<Configuration of the implantable bioimpedance measuring device>

3 is a block diagram of an implantable bioimpedance measuring device according to a preferred embodiment of the present invention. The implantable bioimpedance measuring device includes a bioimpedance measurement sensor 300 inserted into a subcutaneous tissue and outputting a measurement signal measuring a bioimpedance of the subcutaneous tissue, and a resistor and a capacitor connected in series or parallel to the bioimpedance The circuit unit 302 connecting between the measurement sensor 300, the power supply unit 304, and the amplifier unit 306, and the circuit unit 302 and the bioimpedance measurement sensor 300 are connected to each other. According to control, a switching unit 318 selectively connecting some of the electrode pairs of the circuit unit 302 and the bioimpedance measurement sensor 300, and an electrode of the bioimpedance measurement sensor 300 through the circuit unit 302. And a power supply unit 304 for applying a voltage or current to the pair. At this time, the amplifier unit 306 receives and amplifies the measurement signal of the bioimpedance measurement sensor 300 through the circuit unit 302.
In addition, the signal processing unit 308 for generating and outputting measurement information by processing the amplified signal output from the amplifier unit 306, and the measurement information output from the signal processing unit 308 is received to identify the patient input by the user Combined with the information to generate the bioimpedance measurement information, and transmits it to the remote monitoring system through the communication unit 314 and some of the electrode pairs of the bioimpedance measurement sensor 300 for measuring the bioimpedance for the subcutaneous tissue And a control unit 310 for controlling the switching unit 318 so that the circuit unit 302 is selectively connected, a memory unit 312 for storing a variety of information including a processing program of the control unit 310, and a user; The user interface 316 in charge of the interface between the control unit 310 and the power supplied from the outside to charge and provide the charged power to the power supply unit 304 Further it includes a charging section 318.

Here, the circuit unit 302 may be composed of four resistors and a capacitor of 10㎌ for the application of microcurrent and measurement of a signal, and the circuit unit may be formed in various configurations according to the needs of the system. Self-explanatory

Herein, the controller 310 measures a plurality of bioimpedances while sequentially applying power to each of the plurality of electrode pairs included in the bioimpedance measurement sensor 300, and takes an average of the measured multi-measurement impedances. Subcutaneous tissue bioimpedance measurements of the patient can be finally determined.

In addition, the controller 310 measures a plurality of bioimpedances while supplying 50 frequencies of current from 5 kHz to 1,000 kHz for each of the plurality of electrode pairs of the bioimpedance measuring sensor 300. The bioimpedance indicating a, and the low-frequency current to measure the biological impedance indicating the extracellular moisture.

<Method of manufacturing implantable bioimpedance sensor>

The manufacturing method of the implantable bioimpedance sensor 300 according to the present invention will be described with reference to FIG. 4. Referring to FIG. 4, the implantable bioimpedance sensor 300 includes: (a) forming an insulating layer on a substrate; (b) applying a photoresist to the center of the insulating layer; (c) forming an adhesion layer on the insulating layer and the photoresist; (d) forming an electrode layer of a metal material on the adhesive layer; And (e) removing the photoresist and top layer by a lift off method to form an electrode. The insulating layer is formed by oxidizing a silicon dioxide (SiO ₂ ) silicon substrate, and the silicon dioxide layer is laminated to the silicon substrate because it better removes leakage current from the substrate. The adhesive layer is formed of a chromium (Cr) layer. An adhesion layer is an intermediate layer formed between an electrode layer, ie, a metal layer, on a semiconductor to be deposited and to increase adhesion.

More specifically, the substrate is a Si wafer, and a 1 μm thick silicon dioxide layer is deposited on the silicon substrate at about 1000 ° C. The electrodes are patterned and formed by photolithography and lift-off methods, and the spacing between the electrodes is 2 to 3 mm.

The chromium layer having a thickness of 70 nm, which is an adhesive layer, is deposited by sputtering, and the electrode layer made of gold having a thickness of 250 nm is deposited by thermal image deposition. Gold (Au) is preferably formed as an electrode layer because the oxide layer is poorly formed due to the surrounding environment and thus has a low resistance characteristic.

That is, an insulating layer is formed on a substrate as shown in Fig. 4A, and photoresist PR is applied to the center of the insulating layer as shown in Fig. 4B. Thereafter, as shown in FIG. 4C, an adhesive layer, which is a chromium layer, is formed on the insulating layer and the PR layer by sputtering, and as shown in FIG. 4D, the electrode layer is made of gold. It is formed by thermal vapor deposition. Thereafter, as shown in FIG. 4E, by exposing to the ultraviolet light to remove the upper part of the PR layer (Lift Off), a plurality of electrode pairs are formed around a circle, so that the NPSES type bioimpedance sensor illustrated in FIG. Are manufactured.

Heart Failure Monitoring System

The configuration of the heart failure monitoring system including the implantable bioimpedance measuring apparatus 4001 configured as described above will be described with reference to FIG. 5.

The heart failure monitoring system includes a service server 600, a database 602, a plurality of implantable bioimpedance measuring devices 4001-400N, a plurality of manager terminals 5001-500M, and a plurality of customer terminals 5021- 502L).

The service server 600 is connected to a plurality of implantable bioimpedance measuring devices (4001 ~ 400N), a plurality of manager terminals (5001 ~ 500M), and a plurality of customer terminals (5021 ~ 502L) through a wired or wireless network Collect and record the bioimpedance measurement information in the database 602, and determine the heart failure state of the patient according to the bioimpedance measurement information, and the heart failure state to a predetermined manager terminal or customer terminal corresponding to the heart failure patient Provide and guide. In particular, when the heart failure state of the heart failure patient is an abnormal state, the alarm information may be provided to an administrator terminal or a customer terminal predetermined to correspond to the heart failure patient.

The database 602 records the information provided from the service server 600 and particularly stores heart failure monitoring information. The heart failure monitoring information includes patient identification information, manager terminal identification information, customer terminal identification information, and bioimpedance measurement information of subcutaneous tissue.

Each of the plurality of implantable bioimpedance measuring devices 4001 to 400N is wirelessly operated at the request of a patient, a manager, or a medical person, and inserted into a patient's subcutaneous body to measure the bioimpedance of the subcutaneous tissue, and then measure the bioimpedance. The patient identification information is added to the information to generate the subcutaneous tissue bioimpedance measurement information, and is transmitted to the service server 600 located at a remote location through the wireless network. 6 illustrates an example in which any one of the plurality of implantable bioimpedance measuring devices 4001 to 400N is installed in a patient. 6 illustrates an example in which an implantable bioimpedance measuring device is inserted, and B illustrates a Z bioimpedance for device-based liquid monitoring for a hypothetical episode of a liquid load. Point B is the baseline bioimpedance at the load of the liquid overload, and point C indicates that the waste fluid accumulates for several days or weeks (Δt) and the bioimpedance continues to decrease. And point d illustrates the restoration of the baseline bioimpedance ΔZ by diuretic therapy.

In addition, each of the plurality of manager terminals 5001 to 500M receives the heart failure state information or the alarm information from the service server 600 and displays the same to inform the administrator of the heart failure state or alarm of the patient.

In addition, each of the plurality of user terminals 5021 to 502L displays the heart failure risk alert information from the service server 600 to inform the user of the heart failure state or alert of the patient of the corresponding patient.

<How to monitor heart failure>

Now, the heart failure monitoring method applicable to the heart failure monitoring system according to the preferred embodiment of the present invention described above will be described in detail with reference to FIG.

The implantable bioimpedance measuring device according to a preferred embodiment of the present invention is inserted into the subcutaneous of the patient to measure the bioimpedance of the subcutaneous tissue at the request of the patient or medical personnel or the manager has arrived a predetermined cycle (step 700).

When the bioimpedance measurement of the subcutaneous tissue is completed, the implantable bioimpedance measuring device adds patient identification information to the measurement information measuring the bioimpedance to generate bioimpedance measurement information of the subcutaneous tissue, and the service server 600 (Step 702).

When the service server 600 receives the bioimpedance measurement information of the subcutaneous tissue, the heart failure monitoring information corresponding to the patient identification information included in the bioimpedance measurement information of the subcutaneous tissue is included in the bioimpedance measurement information of the subcutaneous tissue. The measured bioimpedance information is stored (step 704).

Whenever the heart failure monitoring information is updated, the service server 600 checks whether the updated bioimpedance falls within a predetermined abnormal (grade 3) range, normal (grade 0) range, and attention attention (grade 1 or 2) range. It is determined whether the heart failure patient is in an abnormal state, a normal state or a state of attention attention (steps 712 and 712).

This is explained in more detail. When moisture accumulates in the body due to heart failure, the moisture accumulated in the body is measured through bioimpedance. That is, the present invention monitors the bioimpedance of the heart failure patient because the heart failure state or the timing of the treatment may be determined through the measurement of the bioimpedance.

Here, the electrical bioimpedance for moisture in vivo is measured using 50 frequencies from 5 kHz to 1,000 kHz. In particular, the high frequency current (50 ~ 1000kHZ) is used to measure the total body water (internal body water), and the low frequency current (5 ~ 50khz) cannot pass through the cell membrane, so it flows through the extracellular moisture membrane, so the electrical resistance of extracellular moisture Use to measure.

As a specific example, the measured bioimpedance value and the monitoring relationship are presented in a paper by William Franklin Peacock IV, MD et al., As shown in “Monitoring (Better Than Chest X-Ray for Predicting Abnormal Pulmonary Fluid”, Table 1 below. And Table 2. In other words, the bioimpedance value is a criterion for determining abnormality (grade 3), normal (grade 0), and attention needs (grade 1 or 2). 18 to 28.8 ohms, 1 or 2 pulmonary venous hypertension, 2 to 13 ohms of bioimpedance, and 3 to 13 to 18 ohms of abnormal pulmonary fluid. .

As described above, when the state of the heart failure patient is determined, the service server 600 transmits the state information of the heart failure patient to an administrator or a customer terminal preset to correspond to the heart failure patient (step 716). The manager or the client terminal provided with the state information of the heart failure patient displays and guides the state information of the heart failure patient (step 718). Here, the patient or manager who is guided to the risk of heart failure may take action according to the risk of heart failure.

4001 ~ 400N: Multiple embedded bioimpedance measuring devices
5001 ~ 500M: Multiple manager terminals
5021 ~ 502L: Multiple customer terminals
600: service server
602: database

Claims (12)

An implantable bioimpedance measuring device inserted under the skin of a plurality of heart failure patients, an administrator terminal or a client terminal for guiding a heart failure state or an alarm when the heart failure state information or alarm information of a plurality of heart failure patients is provided, and heart failure monitoring information is recorded. In the heart failure monitoring system in which the database and the service server connected to the network,
The implantable bioimpedance measuring device,
An implantable bioimpedance measurement sensor inserted into the subcutaneous of the heart failure patient and outputting a measurement signal measuring a plurality of bioimpedances of the subcutaneous tissue, a power supply for supplying power to the implantable bioimpedance measurement sensor, and the implantable bioimpedance measurement sensor A signal processing unit for receiving the measurement signal outputted by the controller to generate measurement information and a communication unit for transmitting the bioimpedance measurement information to the outside, and receiving the measurement information to generate the bioimpedance measurement information and transmitting the bioimpedance measurement information to the communication unit. It is provided with a control unit for transmitting to the service server through,
The implantable bioimpedance sensor has a plurality of electrode pairs,
The control unit supplies a current of 50 frequencies from 5 kHz to 1,000 kHz to a part of the plurality of electrode pairs, and measures a bioimpedance indicating total body water by a high frequency current (50 to 1000 kHZ), and a low frequency current (5 to 50 khz). ) Measures the biological impedance indicating extracellular moisture;
The implantable bioimpedance measuring device further includes a user interface,
If the patient identification information is provided through the user interface, the control unit combines the bioimpedance measurement information and the patient identification information to generate heart failure monitoring information and transmits it to the service server;
The service server stores the bioimpedance measurement information received in the heart failure monitoring information, and each time the heart failure monitoring information is updated, whether the updated bioimpedance falls within a predetermined abnormal range, normal range, and attention range. Determining whether the heart failure patient is an abnormal state, normal state, attention state, and if the heart failure state is abnormal state, characterized in that for transmitting the alarm information to the pre-set manager or customer terminal corresponding to the heart failure patient Heart failure monitoring system. The method of claim 1,
The implantable bioimpedance measuring device further comprises a switching unit for selectively connecting between the power supply unit and the plurality of electrode pairs under the control of the controller; heart failure monitoring system further comprises. The method of claim 1,
The insertion-type bioimpedance measuring device further comprises a charging unit for supplying power to the power source by charging the external power supply; heart failure monitoring system further comprises. delete delete delete delete delete delete delete delete delete

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