JP4008729B2 - Guide wire with pressure sensor - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a guide wire with a pressure sensor in which a pressure sensor for measuring or monitoring blood pressure or physiological body cavity pressure (hereinafter referred to as blood pressure) is attached to the guide wire.
[0002]
[Prior art]
Conventionally, in order to measure or monitor blood pressure, a method of inserting a pressure sensor into a catheter made of a resin tube, a tube coated with a metal braid, or a stainless tube tube has been performed. When this method is inserted into a bent thin blood vessel, the tube body is twisted, deformed due to distortion, bending, etc., and accurate pressure measurement cannot be performed, and it is difficult to insert deep due to its high rigidity. It was.
[0003]
A guide wire is used to guide an angiographic catheter or a catheter used in percutaneous coronary angioplasty to a target vascular site. As this guide wire, Japanese Patent Application Laid-Open No. 11-33004 proposes a guide wire with a pressure sensor using a stainless steel single wire coil. This pressure sensor-equipped guide wire is composed of a guide wire that is flexible and has excellent insertability into a narrow tube such as a blood vessel in a living body, and a pressure sensor incorporated in a tubular member attached to the proximal end portion of the guide wire. .
[0004]
This guidewire with pressure sensor can measure blood pressure with high accuracy and monitor for a long time compared to the method of inserting a pressure sensor into a conventional catheter, and can accurately measure the coronary artery stenosis and its front and back. At the same time, a pressure waveform with less distortion can be obtained. Japanese Patent Application Laid-Open No. 11-25758 describes a hollow stranded wire composed of a multi-wire coil formed by compressing and forming a plurality of strands on the same circumference.
[0005]
[Problems to be solved by the invention]
In the conventional guide wire with pressure sensor, the wire Y is formed by a single wire coil C. Therefore, when the single wire coil C is bent from a straight line along the bend of the blood vessel 10 as shown in FIG. 8A, the portion located outside the bent portion has a gap D between the coil wires and a gap. Arise. As a result, the blood flow enters the single wire coil C from the gap, which causes poor blood circulation due to blood flow disturbance. Further, as shown in FIG. 9, the central axis length L of the single wire coil C is increased by bending, and this increased length becomes longer as the bending angle is larger. The lead wire 41 of the pressure sensor is built in the center of the single wire coil C, and is easily broken by receiving a tensile force by bending.
[0006]
【the purpose】
An object of the present invention is to apply a hollow stranded wire, which is a multi-wire coil, to a guide wire with a pressure sensor advantageously, blood circulation failure due to blood flow disturbance, lead wire damage due to bending, and stable blood pressure without disturbing blood flow rate An object of the present invention is to provide a pressure sensor-equipped guide wire that can measure and monitor blood pressure for a long time.
[0007]
[Means for Solving the Problems]
The pressure guide wire with a sensor of the present invention includes a hollow with a plurality of strands into a cylindrical shape stranded (double track coil), Ri Do and a pressure sensor attached to the distal end or intermediate portion of the hollow stranded wire, wherein The hollow stranded wire is formed by combining the strands having different wire diameters.
[0008]
[Operation and effect of the invention]
In the guide wire with pressure sensor of this invention, since the wire is a hollow stranded wire (double wire coil), it is difficult to form a gap outside the bent portion even if it is bent, and the increase in the central axis length is small. For this reason, the disturbance given to the blood flow is small, and the pulling force applied to the lead wire is also small. In addition, since a multi-spiral spiral groove having a large pitch in the axial direction exists on the outer periphery of the hollow stranded wire, it is easy to ensure blood flow and is suitable for long-time measurement (surgery).
[0009]
Moreover, the hollow stranded-wire (double-track coil) is because not combine different strands of wire diameter, multi-start spiral groove can be increased, even when the hollow stranded wire is inserted through the constriction of blood vessels, ensuring blood flow It is easy to measure and monitor for a long time. Further, the contact frictional resistance with the blood vessel wall is reduced, and the deep insertion in the bent tubule becomes easy.
[0010]
According to the second aspect of the present invention, at least one of the many strands is formed of a radiation opaque material. With this configuration, it is possible to confirm the position of the guide wire or the pressure sensor from the outside with an X-ray without using a separate radiation opaque material.
[0011]
In the configuration of the third aspect , two or more pressure sensors are installed on the hollow stranded wire at a predetermined interval. With this configuration, it is possible to simultaneously measure or monitor the blood pressure at a required site such as before and after the stenosis of the blood vessel.
[0013]
In the structure of Claim 4 , the hollow twisted wire which is the front-end | tip part of the guide wire with a pressure sensor is formed with the radiopaque material. With this configuration, it is not necessary to separately use a radiation opaque material.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows a pressure sensor-equipped guide wire 1 according to a first embodiment of the present invention. The pressure sensor-equipped guide wire 1 includes a hollow stranded wire 2 made of a double-wire coil, and a pressure sensor 3 connected by brazing to the tip of the hollow stranded wire 2. The hollow stranded wire 2 is formed by parallelly arranging and twisting strands 21 made of a large number (for example, 10 or 12) of stainless steel thin wires (for example, wire diameter of 0.06 mm) in a cylindrical shape. ing.
[0015]
The pressure sensor 3 has a metal casing 31 having a cylindrical body with a hemisphere 30 fixed to the tip. Small-diameter fitting portions 32 and 32 are provided at both ends of the casing 31, and windows 33 are provided on the side surfaces. Inside the casing 31, the pressure-sensitive element 4 is accommodated facing the window 33 and fixed with a resin 34. The fitting portions 32, 32 are fitted and brazed to the tips of the hemisphere 30 and the hollow stranded wire 2, and the lead wire 41 of the pressure-sensitive element 4 is disposed through the hollow stranded wire 2.
[0016]
Even if the hollow twisted wire 2 is bent, the guide wire with pressure sensor 1 is inserted through the bent blood vessel 10, and the plurality of strands 21 of the bent portion 22 are, as shown in FIG. It has an effect of causing a mutual shift. For this reason, the bent portion 22 maintains a circular cross section, and a gap is hardly generated between the strands 21 on the outer side 23 of the bent portion 22. As a result, the invasion of the blood flow into the hollow stranded wire 2 is prevented, and the disturbance given to the blood flow is small compared to the case of the single wire coil.
[0017]
Furthermore, even if the hollow stranded wire 2 is inserted through a so-called meandering fine blood vessel that is bent twice or more in different directions, the circular cross section is effectively maintained by the mutual displacement of the strands 21. For this reason, the trouble that the cross section of the blood channel is widened by the deformation of the tubular body due to the continuous twisting, distortion, and bending of the hollow stranded wire 2 (crushed circular section) is surely prevented. Therefore, the blood flow rate is not disturbed, and stable blood pressure enables safe blood pressure measurement and monitoring for a long time.
[0018]
Further, since the extension of the center distance of the bent portion 22 is small and the pulling force applied to the lead wire 41 is small, the lead wire 41 is hardly broken. Further, a multi-spiral spiral groove 24 having a large pitch in the axial direction exists on the outer periphery of the hollow stranded wire 2. For this reason, it is easy to ensure blood flow when the hollow stranded wire 2 is inserted through the narrowed portion of the blood vessel. Further, even if the bent blood vessel is inserted and the hollow stranded wire 2 comes into contact with the blood vessel wall, lubrication is ensured and the contact friction resistance with the blood vessel wall is reduced, so that the deep insertion in the bent thin tube becomes easy. . In addition, the multi-row spiral groove 24 provides a structure in which blood always flows in a certain direction even at a contact portion with the blood vessel wall.
[0019]
FIG. 2 shows a pressure sensor-equipped guide wire 1A according to the second embodiment. In this embodiment, the pressure sensor 3 is interposed in an intermediate portion near the tip of the hollow stranded wire 2. The fitting portions 32 and 32 of the casing 31 are respectively fitted and brazed to the proximal hollow stranded wire 2A and the distal hollow hollow stranded wire 2B. A hemisphere 30 is brazed to the tip of the hollow stranded wire 2B on the tip side. This pressure sensor-equipped guide wire 1A is suitable for use in measuring blood pressure on the proximal side by a predetermined distance from the distal end of a catheter inserted into a blood vessel.
[0020]
FIG. 3 shows a pressure sensor-equipped guide wire 1B according to the third embodiment. In this embodiment, the pressure sensor 3 is brazed to the tip of the hollow stranded wire 2, and the single wire coil 5 is brazed to the tip of the pressure sensor 3. A hemisphere 30 is brazed to the tip of the single wire coil 5. The pressure sensor-equipped guide wire 1B has a high flexibility of the single wire coil 5 that is the tip, and can be easily inserted deeply into a bent blood vessel.
[0021]
4 to 6 show a pressure sensor-equipped guide wire 1C according to a fourth embodiment. In this embodiment, the pressure sensor 3 is brazed to the tip of the hollow stranded wire 2, and the pressure sensor 3 is also brazed to the middle. As shown in FIG. 5, the pressure sensor-equipped guide wire 1 </ b> C can simultaneously measure blood pressure at two locations such as before and after the narrowed portion 11 of the blood vessel 10. Of course, three or more pressure sensors 3 can be attached to the hollow stranded wire 2.
[0022]
FIG. 7 shows a hollow stranded wire 6 according to another embodiment. The hollow stranded wire 6 is alternately arranged with a strand 61 made of a thick wire having a diameter of 0.060 mm and a strand 62 made of a thin wire having a diameter of 0.050. In this case, the hollow stranded wire 6 has an outer diameter of 0.35 mm, which is advantageous for insertion into a bent thin blood vessel such as a coronary artery. As another configuration, the strand 61 made of a thick wire having a diameter of 0.086 mm and the strand 62 made of a thin wire having a diameter of 0.060 may be alternately arranged, and high slipperiness and insertion at the time of insertion into the body. This is suitable when it is necessary to prevent slipping of the part.
[0023]
The hollow stranded wire 6 using the strands 61 and 62 having different wire diameters has a deep multi-strand spiral groove 63 on the outer periphery. As an effect, even if the hollow stranded wire 6 is in contact with the blood vessel wall, a relatively large gap can be secured between the thin wire and the blood vessel wall, and a blood flow path can always be secured. By securing the blood flow path, blood circulation is good even when the blood vessel stenosis is inserted, and contact frictional resistance with the blood vessel wall is reduced, so that deep insertion in the bent tubule is facilitated.
[0024]
One or more of the strands 21 of the hollow stranded wire 2 are formed of a radiation opaque material such as X-rays, or the tip of the hollow stranded wire 2 such as the hollow stranded wire 2B on the tip side is formed. By forming with a radiation opaque material such as X-rays, it becomes easy to accurately set the pressure sensor-equipped guide wires 1, 1A, 1B, 1C at the pressure measurement site.
[Brief description of the drawings]
FIG. 1 is a perspective view of a vicinity of a tip of a pressure sensor-equipped guide wire according to a first embodiment.
FIG. 2 is a perspective view of the vicinity of the tip of a pressure sensor-equipped guide wire according to a second embodiment.
FIG. 3 is a perspective view of the vicinity of the tip of a pressure sensor-equipped guide wire according to a third embodiment.
FIG. 4 is a perspective view of the vicinity of the tip of a pressure sensor-equipped guide wire according to a fourth embodiment.
FIG. 5 is a view showing a usage state of the pressure sensor-equipped guide wire according to the fourth embodiment.
FIG. 6 is a front view of a pressure sensor-equipped guide wire according to a fourth embodiment.
FIG. 7 is a perspective view of a hollow stranded wire of another embodiment.
FIG. 8 is a view showing the usage state of a conventional guide wire with a pressure sensor according to the present invention.
FIG. 9 is a view showing the use state of a conventional guide wire with a pressure sensor.
[Explanation of symbols]
1, 1A, 1B, 1C Guide wire with pressure sensor 2, 6 Hollow twisted wire 21 Elementary wire 3 Pressure sensor 4 Pressure sensitive element 41 Lead wire 5 Single wire coil

Claims (4)

In a guide wire with a pressure sensor comprising a hollow stranded wire in which a plurality of strands are arranged in a cylindrical shape and a pressure sensor attached to the tip or middle portion of the hollow stranded wire , the hollow stranded wire has a different wire diameter. A guide wire with a pressure sensor, wherein the wire is combined. 2. The guide wire with pressure sensor according to claim 1, wherein at least one of the plurality of strands is made of a radiation opaque material . The guidewire with a pressure sensor according to claim 1 or 2, wherein two or more pressure sensors are installed in the hollow stranded wire at a predetermined interval . The guide wire with a pressure sensor according to any one of claims 1 to 3, wherein the hollow stranded wire on the tip side of the pressure sensor is formed of a radiation opaque material. .

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