JP6231417B2 - Diagnostic catheter - Google Patents

Description

  The present invention relates to a diagnostic imaging catheter used for diagnosis of a biological lumen such as a blood vessel.

  Ultrasound for observing the nature of the stenosis, or for observing the condition after treatment, during percutaneous treatment of a stenosis that causes myocardial infarction that occurs in a body lumen such as blood vessels and vessels Alternatively, a diagnostic catheter that acquires an image of a living body lumen using a test wave such as light is used (see Patent Document 1).

  An ultrasonic catheter is used for intravascular ultrasound (IVUS). The ultrasonic catheter is provided with an ultrasonic transducer or an ultrasonic reflection mirror rotatably at the distal end of the insertion portion, inserted into a body cavity, and then rotated via a drive shaft or the like extending from the drive portion on the hand side. Scanning (radial scanning) is common.

  Further, in optical coherence tomography (OCT), an optical probe part in which an imaging core having an optical lens and an optical mirror (transmission / reception part) attached to the tip of an optical fiber is inserted into a blood vessel, While rotating the imaging core, measurement light is emitted from the transmitting / receiving unit at the tip into the blood vessel, and reflected light from the living tissue is received to perform a radial scan in the blood vessel. Then, interference light is generated by causing the received reflected light and the reference light to interfere with each other, and a cross-sectional image of the blood vessel is drawn based on the interference light.

  By the way, in order to insert a catheter into a narrow lumen such as a blood vessel safely and easily, there is a catheter configured such that a guide wire is inserted first and inserted along the guide wire. A lumen (guide wire lumen) through which a guide wire is inserted is formed at the distal end of such a catheter. In addition, in cases where the length of the blood vessel to be observed, such as insertion into a leg blood vessel, is increased, a lumen (guide wire lumen) having a predetermined length in the vicinity of the distal end along the catheter main body as well as the catheter insertion distal end. ) To further guide the guide wire. A lumen (guide wire lumen) of a predetermined length for inserting a guide wire provided along the main body portion of the catheter is referred to as a long monorail portion.

JP 2004-97286 A

  However, a catheter having such a long monorail portion generally needs to flush the lumen (guide wire lumen) of the long monorail portion using an attached flush needle to avoid the risk of air embolism. is there. However, since it is necessary to perform flushing every time it is used, there is a problem that the work is complicated and the procedure time for a doctor or the like is increased.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a technique for reducing the work load of a doctor or the like who uses a catheter and shortening the procedure time.

In order to achieve the above object, the diagnostic imaging catheter according to the present invention has the following configuration. That is,
A diagnostic imaging catheter,
A first lumen through which the guide wire is inserted;
A second lumen through which the guide wire is inserted;
The drive shaft has a retractable catheter lumen,
The second lumen is longer than the first lumen, and at least one communicating opening is formed between the second lumen and the catheter lumen ,
The diameter of the opening is determined based on a ratio between the volume of the catheter lumen and the volume of the second lumen .

  According to the present invention, it is possible to reduce the work load of a doctor or the like who uses a catheter and to shorten the procedure time.

It is a figure which shows the structure of the catheter 10 concerning one Embodiment of this invention. It is a figure which shows a mode that the guide wire 201 concerning one Embodiment of this invention penetrates the 1st guide wire lumen | rumen 103a and the 2nd guide wire lumen | rumen 103b. The figure which shows an example of the internal structure of the front-end | tip part of the catheter 101 concerning one Embodiment of this invention. (A) It is a cross-sectional view of the connection part of the 2nd guide wire lumen | rumen 103b and the catheter sheath 101 which comprise the long monorail part concerning one Embodiment of this invention. (B) It is a longitudinal cross-sectional view at the time of cut | disconnecting the 2nd guide wire lumen | rumen 103b and the catheter sheath 101 concerning one Embodiment of this invention perpendicularly | vertically to a longitudinal direction. It is a figure which shows the flow of the ultrasonic transmission medium which passes the inner tube | pipe of the catheter sheath 101 concerning 2nd Embodiment of this invention, and the 2nd guidewire lumen | rumen 103b at the time of flushing. It is a figure which shows an example of each diameter of several opening which connects the inner tube | pipe of the catheter sheath 101 concerning 2nd Embodiment of this invention, and the 2nd guidewire lumen | rumen 103b. The figure which shows the example which formed the 1 or more hole in the surface of the 2nd guidewire lumen | rumen 103b concerning one Embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Throughout the drawings, the same reference numerals refer to the same components.

<First Embodiment>
1. Configuration of Catheter FIG. 1 is a diagram showing a configuration of a catheter 10 according to an embodiment of the present invention. In the following, an ultrasonic catheter will be described as an example of a catheter. However, the embodiment of the present invention is not limited to an ultrasonic catheter, but can be applied to other types of catheters such as an OCT catheter.

  As shown in FIG. 1, a catheter 10 includes a long catheter sheath 101 inserted into a blood vessel and a connector 102 that is not inserted into the blood vessel and is disposed on the user's hand side for operation by the user. Including. A first guide wire lumen 103a is formed at the distal end of the catheter sheath 101, and the catheter sheath 101 is formed as a continuous lumen from a connection portion with the first guide wire lumen 103a to a connection portion with the connector 102. Has been.

  Further, a second guide wire lumen for inserting a guide wire 201 described later, which is formed along a part of the distal end side of the catheter sheath 101 in parallel with the catheter sheath 101 (for example, on the order of 45 mm to 1500 mm). 103b is provided. An appropriate length of the second guidewire lumen 103b is used according to the length of a blood vessel or the like to be diagnosed (for example, an arm or a leg). As shown in FIG. 2, the guide wire 201 is used by being inserted through the first guide wire lumen 103a and the second guide wire lumen 103b.

  The connector 102 includes a sheath connector 102a configured integrally with the proximal end of the catheter sheath 101 and a drive shaft connector 102b configured integrated with the proximal end of the drive shaft. An anti-kink protector 1021 is provided at the boundary between the sheath connector 102a and the catheter sheath 101. Thereby, a predetermined rigidity is maintained, and bending (kink) due to a rapid change can be prevented. The drive shaft connector 102b is provided with an injection port 1022 to which a syringe (not shown) or the like can be attached in order to fill the entire lumen of the catheter sheath 101 with the ultrasonic transmission liquid. The base end of the drive shaft connector 102b is configured to be connectable to a scanner / pullback unit (not shown).

  Next, the configuration of the distal end portion of the catheter 10 will be described with reference to FIG. In FIG. 3, imaging having an ultrasound transducer unit 301 that transmits and receives ultrasound and a drive shaft 302 that transmits a driving force for rotating the ultrasound transducer unit 301 inside the lumen of the catheter sheath 101. The core 303 can be accommodated, and is inserted through almost the entire length of the catheter sheath 101. The ultrasonic transducer unit 301 includes an ultrasonic transducer 301a and a housing 301b that holds the ultrasonic transducer 301a, and ultrasonic waves are transmitted from the ultrasonic transducer 301a toward the body cavity tissue. The ultrasonic transducer 301a receives a reflected wave from the body cavity tissue.

  The drive shaft 302 is formed in a coil shape, and a signal line is disposed inside the drive shaft 302 and extends from the ultrasonic transducer 301 a to the connector 102. The ultrasonic transducer 301a has a rectangular shape or a circular shape, and is formed by vapor-depositing electrodes on both surfaces of a piezoelectric material made of PZT or the like. The ultrasonic transducer 301a is installed so as to be positioned near the center in the rotation axis direction so that the drive shaft 302 does not cause rotation unevenness.

  The housing 301b has a shape having a notch in a part of a short cylindrical metal pipe, and is formed by cutting out from a metal lump, MIM (metal powder injection molding) or the like. The housing 301 b has an ultrasonic transducer 301 a inside, and the base end side is connected to the drive shaft 302. A short coil-shaped elastic member 304 is provided on the tip side.

  The elastic member 304 is a coil formed of a stainless steel wire, platinum, or an alloy containing platinum, and the elastic member 304 is arranged on the distal end side, thereby improving the stability during rotation of the imaging core 303. To do. Generally, since gold and platinum are metals having high radiopacity, the elastic member 304 is imaged under the image of the X-ray imaging apparatus even when the catheter sheath 101 is inserted into the body cavity. Thereby, the user can easily know the position of the ultrasonic transducer 301a.

  At the boundary portion between the distal end portion of the catheter sheath 101 and the first guide wire lumen 103a, a discharge port 305 for discharging the ultrasonic transmission liquid injected in the priming operation to the outside is provided. Reference numeral 306 denotes a reinforcing coil, which is provided for the purpose of preventing sudden bending of the distal end portion of the catheter sheath 101.

  The first guide wire lumen 103a and the second guide wire lumen 103b have holes through which guide wires can be inserted. The first guide wire lumen 103a and the second guide wire lumen 103b are inserted in advance into the body cavity and used to guide the catheter sheath 101 to the affected area.

  The drive shaft 302 can rotate and slide with respect to the catheter sheath 101, is flexible, and has a characteristic capable of transmitting rotation well, for example, by a multi-layered close contact coil made of a metal wire such as stainless steel. It is configured.

  The inside of the lumen can be observed / photographed 360 degrees by the rotation of the drive shaft 302, but in order to observe / photograph a wider range, the drive shaft 302 is slid in the axial direction relative to the catheter sheath 101. Just do it.

  Specifically, with the sheath connector 102a fixed, the ultrasonic vibration fixed to the internal drive shaft 302 or the distal end thereof is slid by sliding the drive shaft connector 102b toward the base end (in the direction of arrow 104 in FIG. 1). The child unit 301 slides in the axial direction (that is, in the direction of the arrow 307 in FIG. 3). This sliding in the axial direction may be performed manually by the user or electrically.

2. An opening for spatially communicating the lumen of the guide wire lumen and the lumen of the catheter sheath Next, an example of communication of the long monorail portion will be described with reference to FIG. FIG. 4A is a cross-sectional view of a connection portion between the second guide wire lumen 103b and the catheter sheath 101 constituting the long monorail portion. The left side of FIG. 4B shows the second guide wire lumen 103b and the catheter sheath 101 perpendicular to the longitudinal direction at a position where there is an opening 401 that connects the second guide wire lumen 103b and the inner tube of the catheter sheath 101. It is a longitudinal cross-sectional view at the time of cut | disconnecting. The right side is a longitudinal sectional view when cut at a position where there is no opening 401.

  As shown in FIGS. 4A and 4B, an opening 401 that connects the second guide wire lumen 103b and the inner tube of the catheter sheath 101 is formed near the center of the second guide wire lumen 103b. Yes. Here, each lumen diameter, lumen radius, length, cross-sectional area, and volume data of the catheter sheath 101 and the second guide wire lumen 103b are defined as shown in Table 1.

For example, the second guide wire lumen 103b is filled with the priming liquid before passing through the opening 401 communicating with the second guide wire lumen 103b and the catheter sheath 101 and at least the inside of the catheter sheath 101 is filled with the priming liquid. As a condition, the dimension (lumen diameter D ₃ ) of the communicating opening 401 that can secure a necessary flow rate from the volume ratio of the catheter sheath 101 and the second guide wire lumen 103b is expressed by the equation (1). Can be calculated as follows.

As shown in Table 2, if D ₁ = 0.70 mm and D ₂ = 0.40 mm, D3 = 0.23 mm can be calculated from the equation (1).

  The opening diameter is set to a value smaller than the diameter of the guide wire 201 so that the guide wire 201 passing through the second guide wire lumen 103b does not enter the opening 401. In order to avoid the entry of the guide wire to be used into the communicating opening 401, the diameter of the communicating opening needs to be smaller than that of the guide wire, and therefore it is desirable that D3 <guide wire size. In the above example, when the adaptive minimum guide wire size is 0.30 mm, D3 <guide wire size is established, and therefore, there is only one opening that communicates. On the other hand, when the adaptive minimum guide wire size is 0.15 mm, since D3> guide wire size, the opening size is less than 0.15 mm, and providing two or more openings corresponds to an opening size of 0.23 mm. Ensure the flow rate to be used.

  Further, the shape of the opening is usually circular, but is not limited to a circle, and may be formed in an arbitrary shape such as a square, a rectangle, or an ellipse.

  Further, the first guide wire lumen 103 a is provided with the discharge port 305 shown in FIG. 3, and the discharge port 305 corresponds to the opening 401. However, since the first guide wire lumen 103a is usually shorter than the second guide wire lumen 103b, and the length of the first guide wire lumen 103a is approximately 20 mm or less, the necessity for flushing is not high. It is not necessary to provide a configuration corresponding to.

3. Flow of ultrasonic transmission medium during flushing Generally, an injection port for an ultrasonic transmission medium is provided at the proximal end of the catheter 10, and physiological saline is injected (priming) as an ultrasonic transmission medium before operation, and in use. When air bubbles adhere to the surface of the ultrasonic transducer 301a, the air bubbles are removed by injecting (flushing) physiological saline at a high pressure from the base end.

  FIG. 5 is a diagram illustrating the flow of the ultrasonic transmission medium that passes through the inner tube of the catheter sheath 101 and the second guide wire lumen 103b according to the present embodiment at the time of flushing. When the flush operation is performed, an ultrasonic transmission medium flows from the proximal end of the catheter 10 as indicated by an arrow 501. A part of the ultrasonic transmission medium flows from the inner tube of the catheter sheath 101 to the second guide wire lumen 103b through the opening 401 as indicated by an arrow 502. The remaining ultrasonic transmission medium advances toward the distal end of the catheter sheath 101 as indicated by an arrow 503. The ultrasonic transmission medium that has flowed into the second guide wire lumen 103b from the opening 401 is pushed out in the left-right direction on the page, that is, in the directions of the arrows 504 and 505, and discharged from both ends of the second guide wire lumen 103b to the outside. Is done. Thus, when the catheter 10 is flushed, the second guidewire lumen 103b can be flushed at the same time. Therefore, it is possible to shorten the doctor's procedure time.

Second Embodiment
In the first embodiment, an example has been described in which one opening that communicates the inner tube of the catheter sheath 101 and the second guide wire lumen 103b is provided near the center of the second guide wire lumen 103b.

  In contrast, in the second embodiment, an example in which a plurality of openings are formed will be described. When the length of the long monorail portion is less than a predetermined length (for example, less than 235 mm), one opening may be provided as in the first embodiment, but when the length is longer than the predetermined length (for example, 235 mm or more) In order to more efficiently perform the flushing operation of the second guide wire lumen 103b, a plurality of openings are provided at predetermined intervals.

  In that case, the pressure of the ultrasonic transmission medium is larger toward the proximal end side of the catheter sheath 101 and is smaller toward the distal end side. Therefore, in order to make the flow of the ultrasonic transmission medium more efficient, a difference may be provided in the sizes of the plurality of opening diameters. More specifically, as shown in FIG. 6, the opening diameter is made smaller toward the proximal end side of the catheter sheath 101 and the opening diameter is made larger toward the distal end side (the diameter of the opening 601 <the diameter of the opening 602 <the diameter of the opening 603). Diameter). That is, the diameter of each of the plurality of openings is formed such that the diameter is smaller toward the upstream side during priming or flushing, and the diameter is larger toward the downstream side.

  As a result, even in the case of a catheter having a long long monorail length, the flow of the liquid flowing from each opening becomes more uniform as compared with the case where the diameters of the respective openings are the same, and the second guide wire lumen 103b. It is possible to efficiently perform the flash work.

<Third Embodiment>
In the second embodiment, an example in which a plurality of openings for communicating the inner tube of the catheter sheath 101 and the second guide wire lumen 103b is provided has been described.

  In contrast, in the third embodiment, an example in which one or more holes are provided on the surface of the second guide wire lumen 103b in addition to the configuration of the second embodiment will be described.

  As shown in FIG. 7, in addition to the configuration of FIG. 6, a hole 701 is further provided between the opening 601 and the opening 602, a hole 702 is provided between the opening 602 and the opening 603, and the second guide wire lumen 103b is provided. Form on top. The ultrasonic transmission medium that has flowed into the second guide wire lumen 103b from the opening 601 does not always travel in the direction of the arrow 505 but also partially travels in the direction of the opening 602. Then, the ultrasonic transmission medium flowing in from the opening 602 and the ultrasonic transmission medium flowing in from the opening 601 merge, and there is a possibility that the place of the ultrasonic transmission medium disappears at the merge point and bubbles are generated. The same applies to the ultrasonic transmission medium flowing from the opening 602 and the ultrasonic transmission medium flowing from the opening 603. Therefore, by forming the holes 701 and 702, it is possible to allow the ultrasonic transmission medium and the bubbles to escape to the outside, and it is possible to perform a flash operation with higher accuracy.

  In addition, it is possible to perform a more accurate flush operation by providing the positions where the holes 701 and 702 are formed at each joining point of the ultrasonic transmission medium flowing from each opening. The junction point may be calculated based on the inner tube diameter of the catheter sheath 101, the diameter of each opening, the diameter of the second guide wire lumen 103b, and the general flow velocity at the time of flushing.

  10: catheter, 101: catheter sheath, 102: connector, 102a: sheath connector, 102b: drive shaft connector, 103a: first guide wire lumen, 103b: second guide wire lumen, 201: guide wire, 301: super Sonic transducer unit, 301a: ultrasonic transducer, 301b: housing, 302: drive shaft, 303: imaging core, 304: elastic member, 305: discharge port, 401, 601-603: opening, 701-702: hole, 1021: Anti-kink protector, 1022: Injection port

Claims (6)

A diagnostic imaging catheter,
A first lumen through which the guide wire is inserted;
A second lumen through which the guide wire is inserted;
The drive shaft has a retractable catheter lumen,
The second lumen is longer than the first lumen, and at least one communicating opening is formed between the second lumen and the catheter lumen ,
The diameter of the opening is determined based on a ratio between the volume of the lumen of the catheter and the volume of the second lumen . Diameter of said openings, imaging catheter of claim 1, wherein the guide is smaller than the diameter of the wire. A plurality of the openings are formed,
3. The diagnostic imaging catheter according to claim 1, wherein each of the plurality of openings has a smaller diameter toward a proximal end side of the diagnostic imaging catheter and a larger diameter toward a distal end side. The diagnostic imaging catheter according to claim 3 , wherein one or more holes are further formed on the surface of the second lumen. 5. The diagnostic imaging catheter according to claim 4 , wherein the one or more holes are formed at each confluence point of the liquid flowing into the second lumen from the catheter lumen through the plurality of openings. The diagnostic imaging catheter according to any one of claims 1 to 5 , wherein a length of the second lumen is 235 mm or more.

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