JPH1133004A - Guide wire with pressure sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a guide wire which guides insertion of a catheter for angiography or a catheter for percutaneous transluminal coronary angioplasty and in which a semiconductor type pressure sensor for measuring and monitoring blood pressure or physiological coelom internal pressure is mounted in a portion near its end. SOLUTION: A guide wire with an outside diameter of 0.26 to 1.05 mm and a length of 30 to 250 cm, for guiding insertion of a catheter into the heart, has a sensor portion having an X-ray-impermeable end portion and having a semiconductor type pressure sensor for measuring blood pressure, with its pressure-receiving surface exposed to a part near the end portion, and has an extension in which an electrically conductive microwire connecting the sensor to external equipment exists within the wire.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of an in-vivo blood pressure monitor, and more particularly, to a guide wire for guiding an angiographic catheter or a catheter used for percutaneous coronary angioplasty to a target vascular site. And a guide wire equipped with a semiconductor type pressure sensor for measuring and monitoring blood pressure or physiological body cavity pressure near the distal end of the guide wire.

[0002]

2. Description of the Related Art Various measurement methods for monitoring a blood pressure of a heart or the like by inserting a catheter into a blood vessel have been conventionally studied. In order to smoothly insert into such a thin and winding blood vessel in a living body, the insertion member must be naturally thin, flexible, and excellent in flexibility.

Conventionally, a plastic catheter has been used as such a member. As a method of measuring or monitoring blood pressure using this catheter in combination, for example, a patient's blood vessel is filled with physiological saline through the catheter, the outside of the other end of the catheter is connected to an external semiconductor pressure transducer, and the saline is passed through the saline. A method of detecting and monitoring a pressure change and a method of incorporating a small semiconductor pressure transducer into the distal end of a catheter, inserting it into a blood vessel, and monitoring, for example, a local pressure in a heart or a blood vessel have been proposed.

Japanese Patent Application Laid-Open No. 62-47335 discloses a sensor system in which an optical fiber and a diaphragm are combined at the distal end portion of an intravascular insertion catheter.
JP-A-2625, JP-A-64-17262, JP-A-4-141139 and JP-A-4-253840 incorporate a pressure sensor at the distal end of the catheter,
A flexible resin catheter, such as polyolefin or polyvinyl chloride, is described which extends and monitors a conductive wire connected to a sensor.

Japanese Patent Laid-Open Publication No. Sho 64-17627 discloses that
Attach a metal cap to the tip of the catheter,
A capillary type pressure gauge in which a silicon semiconductor pressure chip is fixed to a stainless steel base in the cap is described.

[0006]

However, in the method of detecting and monitoring the blood pressure or the like at a blood vessel insertion site using a catheter equipped with a pressure sensor as described above, the catheter itself is made of a soft plastic material of a relatively soft material. It is difficult to insert into a particularly small blood vessel part because it is made from, and the catheter itself tends to be deformed such as torsion, distortion, bending, compression, etc. by the external stress during the insertion process. This makes it difficult to accurately measure and monitor the blood pressure and the like. Furthermore, accurate blood pressure waveforms and pressure measurements of thinner blood vessels in the heart were not possible with a catheter as small as a conventional catheter.

[0007] From the above, the inventor of the present invention has intensively studied a measurement method which is difficult to perform accurate blood pressure measurement and monitoring under the influence of external stress and the like, as described above. As a result, the present invention has been achieved by focusing on a metal guide wire for guiding a catheter used for coronary artery treatment such as angioplasty to a target vascular site.

That is, this guide wire has a remarkably thin tube diameter, has elasticity peculiar to metal, is excellent in flexibility, and easily deforms such as twisting or bending like a plastic catheter, or The inventor has attempted to solve the above-mentioned problems by attaching a pressure sensor capable of detecting and monitoring blood pressure to the guide wire because it does not stretch.

Accordingly, an object of the present invention is to provide a guide whose main member is formed of a spiral coil and a tubular member made of stainless steel and which has flexibility and is excellent in insertability into a thin tube such as a blood vessel in a living body. An object of the present invention is to provide a guide wire with a pressure sensor in which a semiconductor type pressure sensor for measuring blood pressure is mounted near the distal end of the wire.

[0010]

SUMMARY OF THE INVENTION A guidewire suitable for the present invention is a catheter for balloon angiography and a catheter with a balloon which are conventionally indispensable for cardiac catheterization or percutaneous coronary angioplasty. Inserting guide length is 30 ~ 250cm, outer diameter is 0.26 ~ 1.05m
m is a metal guide wire. This guide wire is configured by mutually fixing an X-ray opaque tip, a sensor part for mounting a sensor for measuring blood pressure, and an extension connected to a measuring device outside the body, and (1) the tip is A spiral coil of platinum wire having a length of 10 to 30 mm, including a safety wire welded with a tin-silver alloy to a stainless steel core wire extended through an extension part and a sensor part, The tip of the safety wire and the tip of the platinum wire, including a part of the platinum wire, are welded to a tin-silver alloy chip whose tip is rounded.
A stainless steel mantle tube with a lumen at 乃至 20 mm,
A semiconductor pressure sensor having a silicon chip as a pedestal is filled and fixed with an epoxy resin so as to expose a pressure receiving surface in a lumen facing a monitor hole provided in the outer tube, and (3)
The extension was a tubular wire composed of a coil in which a stainless steel wire was spirally wound and a stainless steel mantle tube, and the inside of the guide wire was covered with a resin connected to a terminal of the sensor. There is provided a guide wire with a semiconductor type pressure sensor which has conductive fine wiring inside and is connected to a connector at an end of an extension portion.

According to the present invention, the pressure sensor is a semiconductor type sensor, particularly preferably a silicon diaphragm type semiconductor pressure sensor is inserted and the semiconductor type sensor has a temperature compensation circuit. A guidewire is provided.

[0012]

DETAILED DESCRIPTION OF THE INVENTION

[Guide Wire with Sensor] As described above, the guide wire with a pressure sensor according to the present invention is used to guide the insertion of an angiographic catheter into a blood vessel, for example, and at the same time, is used to guide the insertion tip portion. It can measure and monitor blood pressure.
The guide wire with a pressure sensor of the present invention, which is made of this extremely thin metal tubular wire, is extremely excellent in operability when inserting it into a blood vessel.

The excellent operability is as follows: (1) Since the entire wire is a tubular wire having a helical coil-shaped lumen, the wire is rotated while its end is rotated right and left outside the body, for example. The guide wire can be easily advanced into the blood vessel by pushing the guide wire. (2) Since the main member of the guide wire is made of stainless steel because it is a very thin tubular wire, the elasticity peculiar to the metal can be used to advance the tortuous blood vessel without twisting. By taking advantage of these features and extending the guide wire outside the body and connecting it to a measurement monitor and an arteriovenous pressure measurement monitor, as is apparent from the examples described later, the conventional catheter method can be used. Thus, accurate blood pressure measurement or stable blood pressure monitoring can be performed at the affected part and the treatment site directly in the living body.

More specifically, the metallic tubular guide wire having this lumen has an outer diameter of 0.20 to 1.05.
mm, preferably 0.24 to 1.02 mm, more preferably 0.3 to 1 mm. As a result, it is possible to measure a pressure in a micro blood vessel having a diameter of about 1 to 3 mm, which cannot be inserted with a conventional catheter.

The length varies depending on the purpose of use. Generally, a length of 30 to 250 cm is appropriately used, and if necessary, an external connector is connected to an end connector exposed to the outside of the body. Measuring device with an outer diameter of 0.26 to 1.02 mm and a length of 100
It can be connected to a stainless steel extended tubular wire of up to 200 cm in a detachable manner, and can be easily extended and used.

The guide wire with a metal pressure sensor provided by the present invention is an extremely thin thin tube as described above, but is connected to an external measuring instrument fixed to each other as shown in the conceptual diagram of FIG. Extension part 3 to be connected, sensor part 2 with sensor inserted, and X-ray opaque tip part 1
A metal tip with a rounded tip is fixed to the tip 1 thereof, and as described below, the entire wire is a normal piano-shaped helical coil, and a tube having excellent metal elasticity. It is a wire.

That is, referring to FIG. 1, a guide wire with a pressure sensor according to the present invention, which is fixed to each other, has a length of 30 to 250 cm and an outer diameter of 0.26 to 1.05 mm. A tubular wire made of
(1) The distal end portion 1 is a spiral coil 5 made of X-ray opaque platinum and having a length of 10 to 30 mm, and a stainless steel core wire 6 extended through the extension portion 3 and the sensor portion 2. A tip 4 made of a tin-silver-based alloy or platinum containing a safety wire 4 'welded with a tin-silver alloy and having a rounded tip including the end of the safety wire and a part of the platinum wire. (2) The sensor unit 2 is a stainless steel outer tube 8 having a length of 2 to 20 mm, preferably 3 to 10 mm, facing a monitor hole provided in the outer tube. A semiconductor type pressure sensor having a silicon substrate as a pedestal in the cavity is fixed by filling an outer tube 8 with an epoxy resin 7 so that the pressure receiving surface is exposed.
Is a coil 12 in which a stainless steel wire is spirally wound.
And a tubular wire made of a stainless steel mantle tube 13, which is externally connected to a monitor device for measuring blood pressure through a connector 14 at the end, and (4) and a sensor terminal is provided in the lumen of the guide wire. The conductive fine wiring 11 covered with the connected resin is internally provided and connected to the connector 14 at the end of the extension.

As described above, the material is made of a metal such as stainless steel or platinum, and the guide wire body of the present invention is made of a material that does not have to worry that the member elutes or corrodes even when inserted into a living body. You can see that there is.

Therefore, even if the guide wire is intended to insert and guide various catheters as described later, or if it is used for measuring blood pressure which is the main object of the present invention, the guide wire body Is not necessarily required to be coated with a resin such as a fluororesin. However, in the present invention,
More preferably, a guide wire whose outer surface is coated with a resin is suitably used. That is, since a thin guide wire is inserted into a thin blood vessel, the surface of the wire becomes more slippery by, for example, coating with a fluororesin or the like, and the wire is smoothly inserted.

What is important for the present invention is that the guide wire is an extremely fine tubular wire for the purpose as described above. However, since it is made of metal and the whole wire is shaped like a piano wire,
Unlike conventional catheters, it has sufficient strength and elasticity that it is not easily deformed by external stress such as torsion, bending, bending, pulling, etc. There are (see Examples described later).

Therefore, the catheter is used without worrying about being twisted, bent, compressed, or bent due to external stress in a blood vessel during use, such as a conventional plastic catheter. In addition, this wire has the elasticity peculiar to metal, the shape is piano linear as described above, and it is an extremely thin thin tube, so it can be freely bent like a coil and compared with a conventional plastic catheter. It can be handled with the same flexibility and flexibility (see the embodiments described later). Furthermore, conventional plastic catheters are easily stretched by external stress or heat, and careless handling may cause the catheter to be stretched and the wiring in the catheter to be easily broken, making measurement impossible. there were. On the other hand, the guide wire used in the present invention is used without being stretched or shrunk by the body temperature or a pulling operation during handling.

As described above, the conventional catheter method cannot transmit the original blood pressure wave to the external transducer through the liquid medium in the catheter, and the blood pressure in the catheter cannot be increased. It made the monitor unstable and made blood pressure measurements inaccurate. Although the details of the factors are unknown, the catheter can be easily twisted, flexed, or stretched even by operation during use, and external stress caused by such deformation causes the liquid medium or blood flow in the catheter to flow. It may cause instability or inaccuracy. Attempts have been made to improve or reduce these disadvantages of catheterization. For example, Japanese Unexamined Patent Publication (Kokai) No. 64-17627 discloses a conventional catheter 18 in which a metal cap 19 containing a semiconductor pressure sensor 20 is attached to the tip of the conventional catheter as shown in FIG. Proposed.

Indeed, according to this proposal, since the sensor insertion portion is a metal cap, it does not directly affect the sensor due to the deformation as in the conventional catheter, but this cap is no different from the conventional one. Since it is used while being attached, it can be said that the influence of the deformation or the like based on the catheter still affects the pressure receiving surface in the cap.

Further, since the blood pressure measurement is not changed to a method of measuring through a liquid medium used in a conventional catheter method and direct measurement at a target site as in the present invention is not performed, reference is made to FIG. As described above, the details are unknown, but the inaccuracy of the measured value is not improved due to an intermediate medium, and the measurement is extremely complicated and quick in comparison with the measurement method according to the present invention. It lacks urgency when action is required.

Furthermore, in the conventional catheter method, in a thinner blood vessel such as a blood vessel having a diameter of 1 to 3 mm, for example, the catheter is mostly occupied, which tends to change the blood flow state and change the blood pressure. In some cases, such measurement of blood pressure in blood vessels is impossible because it makes the original blood pressure measurement difficult.

[How to Use] When such a guide wire of the present invention is used for measuring a blood pressure or the like, it may be used alone by inserting it into a blood vessel, but usually used as a guide wire. Since it fulfills its purpose, it is used as a guide for inserting various catheters into the target site.
That is, when using a catheter, the catheter is inserted along the guide wire inserted into the blood vessel while passing through the guide wire. For example, it is used in a leading manner in order to guide the insertion of a general-purpose angiography catheter in the treatment of normal heart disease.

Since the insertion of the guide wire is performed under X-ray fluoroscopy, the platinum X-ray opaque portion at the tip of the guide wire is confirmed as a shadow, and this is marked as a marker. And inserted. In addition, since it is helical and flexible, the direction of the insertion site can be easily changed. In addition, this marker not only facilitates insertion of the guidewire itself or the catheter, but also in the present invention, in particular, since the marker can clearly monitor a measurement site such as blood pressure, for example, it is stable for a long time. It enables monitoring.
In order to prevent damage to the blood vessel wall when the lead is inserted into the platinum X-ray opaque part at the tip, a tip made of a tin-silver alloy or platinum, which is a soft metal, is rounded at the tip. The attached chip is fixed.

The guide wire used in the present invention can be used alone including the in-vivo part and the extra-corporeal part. In addition to using the extension wire detachably connected to the guide wire as described above, Depending on the purpose, the extension member outside the living body may be used in combination with a connecting member such as a connection cable or an introducer or a connector such as a torque device.

[Resin Coating] Since the guide wire according to the present invention is inserted into a living body for a long time depending on the purpose of use, the guide wire composed of various members as described above is particularly useful. With respect to a part to be inserted into a living body, special consideration must be given to elution, toxicity, corrosion, etc. of the material of the member from the viewpoint of safety.

Therefore, the stainless steel material of the present guide wire is used as it is, but it is preferable to use the guide wire coated with Teflon (registered trademark) resin in an appropriate combination. As a result, in addition to preventing the above-mentioned problems, the surface of the wire can be more smoothly inserted into a blood vessel by taking advantage of the coating property of Teflon.

Examples of the method of coating the fluororesin include a vacuum deposition method, a hot melt coating, an emulsion coating, and a solution coating.
Further, as the coating material in the present invention, in addition to the above-mentioned fluororesin, in particular, in consideration of chemical resistance, corrosion resistance, insulation, etc., epoxy, polystyrene, ethylene trifluoride, tetrafluoroethylene, polyethylene, polypropylene , Polyester and polycarbonate.

[Sensor and Fine Wiring] In the present invention, a semiconductor pressure sensor mounted on a guide wire includes:
Types include diaphragm type capacitance type, semiconductor diffusion resistance type, semiconductor capacitance type, electromagnetic induction type, piezoelectric element type, force balance type, strain gauge type, and thin film strain sensor type. Particularly, a silicon diaphragm type pressure sensor used in an embodiment described later is a silicon diaphragm type pressure sensor which is constituted by a silicon strain resistance and a silicon diaphragm. When a compressive stress is applied to the pressure receiving surface, the resistance value of the resistance element decreases, and the tensile stress increases the resistance value. Therefore, the pressure detection circuit combines these elements with a bridge circuit to detect a change in resistance. . In addition, each of these elements performs temperature compensation of the resistance.

As the conductive fine wiring connected to the semiconductor sensor, a micro cable obtained by coating a normal ultra-fine conductive line with a fluororesin is preferably used. In addition, a flexible printed wiring board can be appropriately used. That is, it is a flexible printed wiring material in which a copper foil or a ribbon-shaped copper core is bonded to a film such as a polyester film, a fluororesin film, a polyimide film, a polyester film, a polyvinyl chloride film, and the like. Printed circuit,
Low loss printed boards and the like can be mentioned.

[Use] The guide wire itself used in the present invention has been widely used in combination with an in-vivo catheter tail. In particular, when a catheter is inserted into a blood vessel, the catheter is also used as a guide for guiding the catheter to be inserted into a target site. According to the present invention, as a result of mounting the pressure sensor in the lumen near the insertion end of the metal guide wire, the characteristics of the members constituting the guide wire are fully utilized as described above, and the use as a guide wire The purpose is fully utilized (see the example described later), for example, in a target portion of a coronary artery, a blood pressure monitor that can be obtained for a long time and with an accuracy that has not been obtained so far. is there.

The following are examples of use of the guide wire with a pressure sensor according to the present invention. For example, in coronary angiography, which is indispensable for the diagnosis of angina pectoris and myocardial infarction, a catheter is inserted from the brachial artery or the hip artery, and a contrast medium is injected from the origin of the left and right coronary arteries, and A method of taking an image on cine film (referred to as sireangiography) has been adopted. The guidewire according to the present invention is used as a so-called guidewire before injecting a contrast agent, and is suitably used after insertion of the contrast agent to perform blood pressure measurement or monitor measurement at a target site.

[0036] Coronary artery bypass surgery performed by coronary angiography is the most effective treatment for ischemic heart disease. Percutaneous coronary angioplasty (PTCA), which has recently become a popular alternative to bypass surgery
In, a guide wire is passed through the occluded coronary artery, and a catheter with a balloon is inserted into the occluder along the guide wire,
In a method of mechanically expanding and reopening the occluded blood vessel by inflating the balloon, it is suitably used for quickly measuring the pressure before and after the stenosis.

Further, as a method of treating a cardiac catheter, a catheter is inserted from an artery or a vein, and is preferably used for measuring the pressure in the atrium and the ventricle. Because it is understood, it is preferably used in combination with a catheter. Guidewires are also widely used as guides for catheter insertion in procedures such as percutaneous angioplasty (PTA), angiography and valvuloplasty,
It is used for pressure measurement at the tip of the guide wire.
Furthermore, particularly when the sensor site is placed in the distal portion from the balloon through the lumen of a catheter with a balloon such as PTA or PTCA, the blood pressure in the distal portion when the balloon is inflated and the blood flow is stopped can be accurately measured.

In these cases, by using the guide wire with a pressure sensor of the present invention, a direct measurement at a target site can be made, and the catheter tip and the extracorporeal transducer, which are disadvantages of the conventional catheter method, are obtained. It eliminates the need for horizontal alignment, eliminates the need for pressure tubes and flash devices, is simple to operate, and produces a pressure waveform that is less distorted compared to conventional liquid-based systems. Thus, a pressure waveform with less noise can be obtained. Among them, by using the guide wire with the pressure sensor according to the present invention, it is possible to accurately measure or monitor the pressure measurement of the coronary artery stenosis part and the stenosis tip part, which has been regarded as a problem particularly in accuracy from the past. This is a major feature of the present invention.

[0039]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described with reference to the following examples. A method for measuring blood pressure in a blood vessel in a living body using a guide wire with a pressure sensor used in the present invention will be described below. (1) Principle of operation of semiconductor type pressure sensor A semiconductor sensor that converts a pressure change into an electric resistance by a piezoresistive pressure sensor equipped with a Wheatstone bridge on a base for fixing the sensor, amplifies the measured electric resistance, The blood pressure is measured by correcting the voltage with a voltage resistance under the atmosphere by an atmospheric pressure sensor and converting the voltage into a voltage (see FIG. 2). More specifically, when an excitation voltage is supplied to the Wheatstone bridge 15 shown in FIG.
The resistance changes when the silicon membrane 14 receives pressure. On the other hand, another resistive element 16 located behind the resistive element 16 is changed only by the temperature, and the resistance difference between the two is changed to a voltage and converted into a pressure.

The performance of the guide wire with a semiconductor pressure sensor used in the present embodiment is as follows. Operating pressure measurement range: -25 to 300 mmHg Linearity (0 to 200 mmHg): ± 1% or less Frequency characteristics: 200 Hz Time zero point change: 5 mmHg / h or less Temperature zero point change: 0.2 mmHg / ° C Time sensitivity change: 3% / H or less Sensitivity: 25 μV / mmHg When using this guide wire, perform the following electrical safety test. (1) Leakage current test As a leakage current test in accordance with JIS T 100212 method, the property state and single failure state of the exterior leakage current and the patient leakage current are measured by the terms of continuous leakage current and patient measurement current, respectively. . Next, the following performance tests are performed. (2) Rated output voltage, time zero point change, time sensitivity change A guide wire with a pressure sensor is connected to the main body in accordance with the rated output voltage and output sensitivity of the clinical invasive sphygmomanometer of JIST1116, and it is confirmed that the output voltage of the terminal is within the rating. Next, the suitability of the calibration signal was confirmed, and the guide wire with pressure sensor was
For load pressures in the range of mHg, confirm that the measured pressures have a display accuracy within ± 1% of the load pressure value. 2. Time zero point change Then, after adjusting the output voltage of the output terminal to 0 volt,
Confirm that the output voltage change after one hour has passed is less than 5 mmHg / h. 3. Next, similarly, it is confirmed that the output voltage change corresponding to 100 mmHg is less than 3% / h after one hour. (3) Bending test The outer diameter used in the present invention is 0.36 mm and the length is 180 cm.
The bending strength is examined by wrapping the guide wire of No. 1 around a rod having a diameter of 50 mm and restoring the original shape when the hand is released. The guide wires used in the present invention were suitable without any abnormality.

Example 1 In a case of a coronary artery stenosis, a guide wire with a pressure sensor according to the present invention, in which a pressure sensor is a semiconductor type, is used. The PTCA balloon was inflated at the site where the stenosis occurred, and the blood pressure was measured at the site immediately before the stenosis before and after the treatment. In order to clarify the superiority of the present invention, a comparative example will be described in which blood pressure waves measured by a guiding catheter (GC curve in the figure) are monitored simultaneously. FIG. 4A shows a pressure waveform before the balloon dilation of the stenosis portion, and FIG. 4B shows a pressure waveform after the balloon dilation. The PG curve in the figure is a blood pressure wave by the guide wire with the pressure sensor according to the present invention. , GC curves show blood pressure waves by the guiding catheter, respectively.

From these results, before PTCA treatment, there is no difference between the systolic blood pressure values when the heart contracts and the blood flow becomes the fastest, but the blood flow becomes slow when the heart is expanded. It is confirmed that there is a large difference in the diastolic blood pressure at the time. After the PTCA treatment, the stenosis is opened, and blood flows into the microvessels ahead, and the blood flow at the measurement site is improved. This indicates that the systolic blood pressure value measured by the present invention is higher. It is well understood that, besides what has been done, the low blood pressure values are also shown higher.

From the above, a clear difference before and after PTCA operation as obtained by the above-mentioned method of the present invention could not be measured and confirmed from blood pressure waves by the conventional method. It is a major feature of the present invention that the results after PTCA operation can be clearly confirmed from the blood pressure waves obtained by the method.

(Embodiment 2) As described above, the guide wire according to the present invention is an extremely thin wire as compared with the conventional catheter. After measuring the blood pressure, the guide wire was advanced over the stenosis, and the pressure waveform of the microvessels at the stenosis tip during PTCA surgery, which was impossible with the conventional method, was measured. The results are shown in FIG. Was. In FIG. 5, the curve A is the pressure waveform at the site of the stenosis before the stenosis, and the curve B is the pressure waveform at the tip of the stenosis during the PTCA treatment obtained for the first time by the present invention.

[0045]

By using the guide wire with a metal pressure sensor according to the present invention for an angiographic catheter or percutaneous coronary angioplasty, it is possible to use a conventional catheter-based liquid medium as a medium or a catheter. In the method of inserting a pressure sensor into the blood pressure, blood pressure can be measured with accuracy that could not be obtained, stable monitoring can be performed for a long time, and endpoint evaluation of the monitor can be easily performed from the obtained blood pressure waveform. can do. Especially in pressure measurement of coronary artery stenosis and its stenosis tip, which was regarded as a problem in accuracy, accurate measurement and pressure waveform with little distortion are obtained, so that post-operative therapeutic effect and hemodynamics are accurately grasped. Is what you can do.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram of a guide wire equipped with a semiconductor type pressure sensor of the present invention.

FIG. 2 shows a system diagram of the pressure measurement and monitor of the present invention.

FIG. 3 is a conceptual diagram of a semiconductor pressure sensor used in the present invention.

FIG. 4 shows pressure waveforms before and after a stenosis portion by a guide wire with a pressure sensor according to the present invention before and after PTCA operation.

FIG. 5 shows a pressure waveform at a stenosis tip by a guide wire with a pressure sensor according to the present invention after PTCA operation.

FIG. 6 shows a catheter with a metal cap fitted with a pressure sensor according to a comparative example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Guide wire tip part 2 Guide wire sensor part 3 Guide wire extension part 4 Tip with rounded tip 4 'Stainless steel safety wire 5 Platinum spiral wire tube 6 Stainless steel core wire 7 Epoxy resin 8 Stainless steel sheath tube 9 Monitor hole 10 Silicon substrate 11 Fine wiring 12 Stainless steel spiral wire tube 13 Stainless steel outer tube 14 Connector 15 Epizo resistance pressure sensor 16 Comparative resistance element (temperature compensation element) 17 Silicon membrane 18 Catheter 19 Metal cap 20 Pressure sensor

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[Procedure amendment]

[Submission date] October 29, 1997

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0011

[Correction method] Change

[Correction contents]

Further, according to the present invention, the pressure sensor is a semiconductor type sensor, particularly preferably a silicon diaphragm type semiconductor pressure sensor mounted , and the semiconductor type sensor has a temperature compensating circuit. Wire is provided.

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0016

[Correction method] Change

[Correction contents]

Although the guide wire with a metal pressure sensor provided by the present invention is an extremely thin tube as described above, it is connected to an external measuring device fixed to each other as shown in the conceptual diagram of FIG. An extended portion 3, a sensor portion 2 on which a sensor is mounted, and a tip 1 that is opaque to X-rays. A tip having a rounded metal tip is fixed to the tip 1 and will be described below. Thus, the entire wire is a normal piano linear spiral coil, and is a tubular wire with excellent metal elasticity.

Claims (5)

[Claims] An outer diameter for guiding a catheter into a heart is 0.26 to 1.05 mm and a length is 30 to 250 c.
m, the guide wire has a tip portion that is impermeable to X-rays and a sensor portion having a semiconductor pressure sensor for measuring blood pressure with a pressure receiving surface exposed at a portion close to the tip portion and the wire. A guide wire with a pressure sensor, comprising: an extension portion having conductive fine wiring therein for connecting the sensor and an external device. 2. A tip part, a sensor part, and an extension part which constitute the guide wire are fixed to each other. (1) The tip part is a spiral coil of a platinum wire having a length of 10 to 30 mm. A stainless steel safety wire welded with a tin-silver alloy is included in a stainless steel core wire extended through the extension part and the sensor part, and the end of the safety wire and a part of the platinum wire are connected. (2) Welded to a tin-silver alloy tip with a rounded tip
The sensor part is a stainless steel outer tube having a length of 2 to 20 mm and having a lumen, and a semiconductor type pressure sensor having a silicon chip as a pedestal in a lumen facing a monitor hole provided in the outer tube. (3) The extension is a tubular wire composed of a coil in which a stainless steel wire is spirally wound and a stainless steel mantle tube, and the extension of the guide wire. 2. The guide with pressure sensor according to claim 1, wherein a conductive micro cable covered with a resin connected to a terminal of the sensor is provided inside the cavity and connected to a connector at an end of the extension. wire. 3. The guide wire with a pressure sensor according to claim 1, wherein an outer surface of the guide wire is covered with a resin. 4. The guide wire with a pressure sensor according to claim 1, wherein the semiconductor type sensor has a temperature compensation circuit. 5. The extension of the guide wire has an outer diameter of 0.26 to 1.02 for connection to an external device at an end.
5. A detachable connection with an extension wire made of stainless steel and having a length of 100 to 200 cm in mm.
The guide wire with a pressure sensor described in any one of the above.