JP6459408B2 - Support catheter - Google Patents

Description

  The present invention relates to a rapid exchange type support catheter that is used together with a treatment catheter and a guiding catheter and guides the treatment catheter to a treatment site.

  In percutaneous coronary intervention (PCI), a support catheter may be used together with a therapeutic catheter and a guiding catheter. As the support catheter, for example, a rapid exchange catheter system as disclosed in Patent Document 1 is known. . The rapid exchange catheter system of Patent Document 1 has a catheter body constituted by an exchange member and a shaft. The distal end side of the catheter body is constituted by an exchange member, and the proximal end side of the catheter body is constituted by a shaft. The rapid exchange catheter system is used by being inserted from the proximal opening of the guiding catheter and the insertion tube protruding from the distal opening of the guiding catheter.

JP-A-6-197972

  As one of the therapeutic catheters used with the rapid exchange catheter system of Patent Document 1, for example, there is a balloon catheter, and the balloon catheter has a balloon at a tip portion thereof. In addition, a stent is sheathed around the balloon, and the balloon is inflated with the balloon inserted into the stenosis site, so that the stent expands and expands to expand the stenosis.

  The stent is a member made of, for example, stainless steel, and is easily plastically deformed to facilitate expansion and expansion. For this reason, even a small force causes plastic deformation. The stent having such a feature may be caught by the replacement member when the balloon catheter is pushed forward, and may be plastically deformed, for example, the stent may be locally swollen if pushed in the hooked state. On the other hand, when the stent is caught on the replacement member or the like, a reaction force acts on the operator's hand from the treatment catheter, and therefore, the operator once stops pushing the treatment catheter when receiving the reaction force.

  However, the reaction force acting on the hand of the practitioner can occur not only when the stent is caught by the exchange member but also in various cases such as when the wire and the balloon catheter are entangled in the guiding catheter. For this reason, the practitioner may not be able to determine in which state the reaction force is acting, and may accidentally push the treatment catheter forward, and the stent caught on the insertion tube may be expanded and deformed.

  Accordingly, an object of the present invention is to provide a support catheter that can suppress deformation of the distal end portion of the therapeutic catheter.

  The support catheter of the present invention is used together with a treatment catheter for treating a treatment site, and a guiding catheter into which the treatment catheter is inserted and guides the treatment catheter in a blood vessel. A support catheter that has a length inserted from the proximal opening of the guiding catheter and protrudes from the distal opening of the guiding catheter, and guides the distal end of the therapeutic catheter to the treatment site, A distal shaft that forms a distal end portion of the support catheter, and a proxy shaft that forms a proximal end portion of the support catheter, the proxy shaft being Projecting from the tip opening of the guiding catheter A proximal end portion has a position confirmation portion, and the position confirmation portion is a treatment catheter side for confirming an insertion depth in a blood vessel in a state where the treatment catheter is inserted into the guiding catheter. By aligning the position with the depth marker, the positional relationship between the distal end portion of the treatment catheter and the distal shaft can be grasped.

  According to the present invention, since the positional relationship between the distal end portion of the treatment catheter and the distal shaft can be grasped, if a reaction force acts on the hand of the treatment catheter while the treatment catheter is being pushed forward, It becomes easy to determine whether or not the cause of the force is a hook on the distal shaft of the distal end portion of the treatment catheter. As a result, it is possible to prevent the treatment catheter from being pushed in forcefully to deform the distal end portion of the treatment catheter.

  According to the present invention, the positional relationship between the distal end portion of the treatment catheter and the distal shaft can be grasped by the operator who is outside the guiding catheter, and deformation of the distal end portion of the treatment catheter can be suppressed. .

It is a figure which shows the state which used the support catheter of this invention with the treatment catheter and the guiding catheter. It is a side view which shows the support catheter and treatment catheter of FIG. FIG. 3 is an enlarged view showing a proximal end side of the support catheter and the treatment catheter of FIG. 2 in an enlarged manner. It is an enlarged view which expands and shows the base end side of the support catheter and treatment catheter of FIG.

  Hereinafter, a support catheter 1 according to an embodiment of the present invention will be described with reference to the drawings. In addition, the concept of the direction used in the following description is used for convenience in description, and does not limit the direction of the configuration of the invention in that direction. Further, the support catheter 1 described below is only one embodiment of the present invention. Therefore, the present invention is not limited to the embodiments, and additions, deletions, and changes can be made without departing from the spirit of the invention.

  As a technique for dilating the stenosis 3 formed in the coronary artery 2 as shown in FIG. 1, for example, percutaneous coronary intervention (PCI) is known. In PCI, a guiding catheter 4, a balloon catheter 5, and a support catheter 1 are mainly used.

<About guiding catheter>
The guiding catheter 4 is inserted into a blood vessel, for example, the radial artery 51, and is a catheter for guiding the balloon catheter 5 and the support catheter 1 in the blood vessel. The guiding catheter 4 includes a guiding catheter main body 11, a tip side tip 12, and a Y-type connector 13.

  The guiding catheter main body 11 has a long tube shape, and is configured such that the balloon catheter 5 and the support catheter 1 can be inserted into the guiding catheter main body 11. The guiding catheter body 11 is a bendable cylindrical flexible tube that can push the inside of the blood vessel to be bent. A distal tip 12 is provided at the distal end of the guiding catheter body 11. The distal tip 12 is a cylindrical member made of a polyamide elastomer blended with bismuth oxide or the like as a contrast agent, and is integrally molded with the distal end portion of the guiding catheter body 11.

  The Y-type connector 13 has a main body portion 13a and a side arm 13b. The main body portion 13 a has a substantially cylindrical shape, and the distal end portion of the main body portion 13 a is attached to the proximal end portion of the guiding catheter main body 11. Further, a check valve (not shown) is provided in the main body portion 13a so that blood does not flow backward from the main body portion 13a. Further, a side arm 13b branched from the main body portion 13a and extending obliquely toward the base end side of the main body portion 13a is formed on the outer peripheral portion of the main body portion 13a, and a drug solution or a contrast agent is supplied from the side arm 13b. It can be injected. Moreover, it has the base end side opening 13c in the base end of the main-body part 13a, The balloon catheter 5 and the support catheter 1 can be inserted now from the base end side opening 13c.

<About balloon catheter>
A conventionally known balloon catheter 5 that is a therapeutic catheter can be appropriately employed. The balloon catheter 5 is a catheter that is inserted into the stenosis part 3 in the coronary artery and pushes and expands the stenosis part 3. The balloon catheter 5 is, for example, a rapid exchange type (RX type) catheter, and includes a treatment catheter body 21 and a connector 22 as shown in FIGS. 1 and 2. The treatment catheter body 21 is formed in a long tube shape, and a pressure fluid can flow through the connector 22 through the connector 22. A balloon 23 covered with a stent 24 may be provided at the distal end portion of the treatment catheter main body 21. As the stent 24, a conventionally known stent can be appropriately employed. In the present embodiment, the treatment catheter main body 21 has a stent 24 and a balloon 23 at its distal end portion. The balloon catheter 5 configured as described above is used together with the guiding catheter 4 and the support catheter 1.

  Further, two depth markers 25 and 26 are provided on the proximal end portion of the treatment catheter main body 21. The depth markers 25 and 26 are substantially annular members made of a material containing a contrast agent, and are covered and fixed to a proximal end portion of the treatment catheter main body 21. Depth markers 25 and 26 that are treatment catheter side depth markers are arranged at intervals in the axial direction of the treatment catheter body 21, and one depth marker 25 is used for treatment from the distal end of the treatment catheter body 21. It is arranged at a position separated by a distance L along the catheter body 21. The depth markers 25 and 26 arranged in this way appear to have shadows of the depth markers 25 and 26 under radioscopy. Therefore, it is possible to confirm the insertion depth of the balloon catheter 5 inserted into the blood vessel by confirming the position of the shadow of each depth marker 25, 26 in the blood vessel (for example, the radial artery 51 and the ascending aorta 52 described later). It can be done.

<About support catheter>
The support catheter 1 is for guiding the balloon 23 of the balloon catheter 5 to a position closer to the stenosis 3 than the entrance of the coronary artery 2, that is, to the stenosis 3, and when the balloon 23 is inserted into the stenosis 3. This is a catheter for supporting the balloon 23. As shown in FIG. 2, the support catheter 1 includes a support catheter main body 31 and a hub 32, and the support catheter main body 31 includes a distal shaft 33 and a proxy shaft 34. The distal shaft 33 is formed in a substantially cylindrical shape into which the balloon catheter 5 can be inserted, and constitutes the distal end portion 1 a of the support catheter 1. The distal shaft 33 has a shaft body 35, a tip end 36, and a covering tube 37.

  The shaft main body 35 is constituted by a substantially cylindrical member having a three-layer structure having three layers of an inner layer, a reinforcing layer, and an outer layer. The inner layer is made of, for example, polytetrafluoroethylene (PTFE) or tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA), and the outer layer is made of, for example, a polyamide in which a contrast agent is blended with a polyester, a polyamide elastomer, or the like. Made of material. In addition, the material of an inner layer and an outer layer may be comprised using the mutually same material, and is not limited to the above materials. Between the inner layer and the outer layer, a mesh-like generally cylindrical member made of stainless steel is embedded, and this mesh-like cylindrical member constitutes a reinforcing layer. The outer peripheral surface of the shaft body 35 is coated with a hydrophilic polymer containing polyurethane, diphenylmethane diisocyanate (MDI), polyvinylpyrrolidone (PVP), or the like.

  A tip tip 36 is integrally provided at the tip of the shaft main body 35 thus configured. The distal tip 36 is made of, for example, a polyamide elastomer mixed with bismuth oxide as a contrast agent, and is formed in a substantially cylindrical shape. The distal tip 36 is radiopaque so that a shadow appears under radioscopy. A distal end tip 36 is integrally formed at the distal end of the shaft main body 35, and the outer peripheral surface of the proximal end side portion of the shaft main body 35 is covered with a covering tube 37. The covering tube 37 is a substantially cylindrical member made of a resin material having thermoplasticity, and is covered on the base end side portion of the shaft body 35. When heat is applied to the covering tube 37 in the exterior state, the covering tube 37 is plastically deformed, and the covering tube 37 is attached to the outer peripheral surface of the shaft main body 35. Further, a proxy shaft 34 is interposed between the covering tube 37 and the shaft main body 35, and the proxy shaft 34 is fixed to the distal shaft 33 by attaching the covering tube 37 to the shaft main body 35. It is like that.

  The proxy shaft 34 is a long wire made of stainless steel, for example, and the surface thereof is coated with PTFE. The proximal shaft 34 is fixed to the distal shaft 33 by sandwiching the tip portion between the shaft body 35 and the covering tube 37. The proxy shaft 34 attached to the distal shaft 33 in this way constitutes the proximal end portion 1 b of the support catheter 1. Further, two depth markers 38 and 39 are provided at the intermediate portion of the proxy shaft 34. The two depth markers 38 and 39, which are support catheter side depth markers, are substantially annular members made of a material containing a contrast agent, and are externally fixed to the proxy shaft 34 and fixed. The depth markers 38 and 39 are arranged at intervals in the axial direction of the proxy shaft 34 so that the shadows of the depth markers 38 and 39 appear under radioscopy. Therefore, the insertion depth of the support catheter 1 inserted into the blood vessel can be confirmed by confirming the position of the shadow of each depth marker 38, 39 in the blood vessel.

  Further, the proximal shaft 34 is formed to be longer than the entire length of the guiding catheter 4, and the shaft main body 35 extends from the distal end side opening 4 a of the guiding catheter 4 with the support catheter 1 inserted into the guiding catheter 4. The proximal end portion 34a of the proximal shaft 34 projects from the proximal end opening 4b of the guiding catheter 4 (that is, the proximal end opening 13c of the Y connector 13). That is, the support catheter 1 has a length that can be inserted from the proximal end side opening 4 b of the guiding catheter 4 so that the distal end portion of the support catheter 1 can protrude from the distal end side opening 4 a of the guiding catheter 4. . A position confirmation marker 41 is provided on the proximal end portion 34 a of the proxy shaft 34.

  The position confirmation marker 41 is a substantially annular member and is visible to the practitioner, that is, has visibility. The position confirmation marker 41 is provided on the proximal end side portion 34a of the proxy shaft 34 as described above, and the distal end portion of the distal shaft 33 projects from the distal end side opening 4a of the guiding catheter 4 in the proximal end side portion 34a. In this state, the guiding catheter 4 is positioned outside the proximal end side opening 4b. That is, the position confirmation marker 41 is located at the proximal end side portion 34a of the proximal shaft 34 projecting from the proximal end side opening 4b of the guiding catheter 4, so that the practitioner does not go through a monitor or the like during the treatment. It can be visually recognized. The position confirmation marker 41 is located on the proximal side of the depth markers 38 and 39 and is located at a distance L from the proximal end of the distal shaft 33 along the proxy shaft 34. When the balloon catheter 5 is placed along the balloon catheter 5, the position of the balloon catheter 5 can be aligned with one of the depth markers 25.

  A hub 32 is provided at the proximal end of the proxy shaft 34. The hub 32 is a cylindrical member made of polyamide elastomer or the like, and can be held by a practitioner with a finger. The hub 32 plays a role as an operation part of the support catheter 1, and the practitioner operates the support catheter 1 by grasping and moving the hub 32.

<How to use the support catheter>
The support catheter 1 configured in this way is used together with the guiding catheter 4 and the balloon catheter 5 in the PCI as described above. Hereinafter, PCI performed using the support catheter 1, the guiding catheter 4, and the balloon catheter 5 will be described with reference to FIGS. In PCI, the practitioner first punctures the radial artery 51 with a needle (not shown), and inserts the sheath 7 at the puncture site. Next, the guiding catheter 4 is inserted into the radial artery 51 through the sheath 7, and the guiding catheter 4 is pushed forward until the distal opening 4a of the guiding catheter 4 reaches the entrance 2a of the coronary artery 2 (ie, near the stenosis 3). It is done. Thereafter, the support catheter 1 is inserted from the proximal end side opening 4 b of the guiding catheter 4. The support catheter 1 is pushed forward in the guiding catheter 4 until the distal end side portion 1a protrudes from the distal end side opening 4a. As a result, the distal end portion 1 a of the support catheter 1 is inserted into the coronary artery 2 and further reaches the stenosis 3. When the distal end portion 1 a of the support catheter 1 reaches the stenosis 3, the balloon catheter 5 is inserted from the proximal opening 4 b of the guiding catheter 4. The balloon catheter 5 is advanced until the tip of the balloon catheter 5 reaches the distal shaft 33 as shown in FIG.

  One depth marker 25 is formed on the balloon catheter 5 at a distance L from the distal end of the balloon catheter 5 along the therapeutic catheter body 21, and the support catheter 1 is proximal from the proximal end of the distal shaft 33. A position confirmation marker 41 is formed at a position separated by a distance L along the shaft 34. Therefore, when the tip of the balloon catheter 5 approaches and reaches the distal shaft 33, the position of one depth marker 25 and the position of the position confirmation marker 41 are matched. That is, it is possible to grasp that the distal end of the balloon catheter 5 has reached the proximal end of the distal shaft 33 by pushing the balloon catheter 5 and aligning one depth marker 25 with the position confirmation marker 41.

  Thus, since the positional relationship between the distal end of the balloon catheter 5 and the distal shaft 33 can be grasped by the positional relationship between the position confirmation marker 41 and one depth marker 25, the distal end of the balloon catheter 5 approaches the distal shaft 33. I can grasp that. Therefore, even if a reaction force acts on the hand of the balloon catheter 5 while the balloon catheter 5 is being pushed forward, it is easy to determine whether or not the cause of the reaction force is the hook of the stent 24 on the distal shaft 33. Thus, it is possible to prevent the balloon 24 from being forcibly pushed in and deforming the stent 24 (that is, the distal end portion of the balloon catheter 5). In particular, when the distal end of the balloon catheter 5 reaches the distal shaft 33, the positions of the one depth marker 25 and the position confirmation marker 41 are matched so that the catheters 1 and 5 are connected to each other from the cause of the reaction force. It is easy to eliminate the entanglement and to identify the cause of the reaction force. In addition, as shown in FIG. 4, the depth marker 25 and the position confirmation marker 41 are aligned outside the guiding catheter 4 so that the practitioner can directly confirm with the eyes. Therefore, it is not necessary to confirm the positions of the one depth marker 25 and the position confirmation marker 41 while moving the range through which the radiation is transmitted, and it is easy to confirm the alignment.

  When the distal end of the balloon catheter 5 reaches the proximal end of the distal shaft 33, the practitioner carefully pushes the distal end portion of the balloon catheter 5 into the proximal shaft 34 while paying attention to the magnitude of the reaction force received at hand. For example, if the balloon catheter 5 does not move even when the balloon catheter 5 is pushed, the stent 24 may be caught on the proximal end of the distal shaft 33. Therefore, the balloon catheter 5 is slightly placed on the proximal end side of the guiding catheter 4 once. Work is done to push it back and push it again. When the distal end portion of the balloon catheter 5 is inserted into the distal shaft 33 and protrudes from the distal end of the distal shaft 33, the distal end portion of the balloon catheter 5 is inserted into the stenosis portion 3, and the balloon 23 and the stent 24 are inserted into the stenosis portion 3. When positioned, the pushing of the balloon catheter 5 is stopped.

  In this manner, the balloon catheter 5 is guided to the entrance 2a of the coronary artery 2 by the guiding catheter 4 by being pushed through the guiding catheter 4 and further guided to the stenosis 3 by the support catheter 1. At this time, since the distal shaft 33 of the support catheter 1 extends to or near the stenosis 3, the balloon catheter 5 is supported by the distal end portion of the distal shaft 33. That is, a force against the reaction force received from the stenosis 3 can be applied to the distal end of the balloon catheter 5 from the distal shaft 33, and a sufficient force is applied to the distal end of the balloon catheter 5 to enter the stenosis 3. A balloon 23 can be inserted. Thus, the pressure fluid is sent from the supply device (not shown) to the balloon 23 inserted into the narrowed portion 3 through the tube 27, and the balloon 23 is inflated by the pressure fluid. At the same time, the stent 24 is expanded and expanded, and the stenosis 3 is expanded. Thereby, the blood flow in the stenosis 3 is recovered.

  In the support catheter 1 configured as described above, the position confirmation marker 41 is formed separately from the depth markers 38 and 39, and the depth markers 38 and 39 are arranged on the distal side of the position confirmation marker 41. As a result, the position confirmation marker 41 is aligned with the depth marker 25 on the outside of the guiding catheter 4, and the depth markers 38 and 39 are arranged in the guiding catheter 4 to grasp the insertion depth of the support catheter 1. be able to.

[Other Embodiments]
Regarding the procedure in which the support catheter 1 of the present embodiment is used, the method of approaching from the femoral artery described in the method of approaching from the PCI radial artery may be used, and the procedure in which the support catheter 1 is used is limited. Not. In the support catheter 1, the stent 24 is sheathed on the balloon 23, but the stent 24 is not necessarily sheathed on the balloon 23. Further, the treatment catheter is not limited to the balloon catheter 5 and may be a catheter such as a rotablator (RA) and a directional atherectomy (DCA).

  Furthermore, the distal shaft 33 of the support catheter 1 does not necessarily have a three-layer structure, and may be a single-layer structure, a two-layer structure, or a structure having four or more layers. Further, the material constituting the distal shaft 33 and the proxy shaft 34 of the support catheter 1 is not limited to the above-described materials, and any suitable material may be used. Further, the position confirmation marker 41 does not necessarily need to be a visible annular member as described above, and may be a simple unevenness that can be confirmed with a finger or the like. Further, the position confirmation marker 41 does not necessarily need to be separated from the proximal end of the distal shaft 33 by a distance L, and may be arranged so as to be shifted to the proximal end side or the distal end side of the proxy shaft 34. That is, the position confirmation marker 41 may be disposed at a position where the positional relationship (ie, distance) between the distal end portion of the balloon catheter 5 and the distal shaft 33 can be understood when the position confirmation marker 41 is located. By grasping the positional relationship, it is possible to suggest that the practitioner should move the balloon catheter 5 carefully, and deformation of the distal end portion of the balloon catheter 5 such as the stent 24 can be suppressed.

DESCRIPTION OF SYMBOLS 1 Support catheter 1a Tip side part 1b Base end side part 2 Coronary artery 2a Inlet 3 Stenosis site 4 Guiding catheter 4a Tip side opening 4b Base end side opening 5 Balloon catheter 23 Balloon 24 Stent 25 One depth marker 33 Distal shaft 34 Proximal Shaft 38, 39 Depth marker 41 Position confirmation marker

Claims (4)

A treatment catheter for treating a treatment site; and used together with a guiding catheter for inserting the treatment catheter and guiding the treatment catheter in a blood vessel, from a proximal opening of the guiding catheter A support catheter that is inserted and has a length protruding from the distal opening of the guiding catheter, and guides the distal end portion of the treatment catheter to the treatment site;
A distal shaft that is formed in a tube shape into which the therapeutic catheter can be inserted, and that forms a distal end portion of the support catheter;
Comprising a proximal shaft constituting a proximal end portion of the support catheter,
The proximal shaft has a position confirmation portion on a proximal side portion protruding from a proximal side opening of the guiding catheter,
The position confirmation unit aligns the position of the treatment catheter side depth marker for confirming the insertion depth in the blood vessel in a state where the treatment catheter is inserted into the guiding catheter. A support catheter capable of grasping a positional relationship between a distal end portion and a proximal end of the distal shaft. The proximal shaft has a support catheter side depth marker for confirming the position in the blood vessel,
The support catheter according to claim 1, wherein the position confirmation unit is configured separately from the support catheter side depth marker.   The position confirmation unit is configured so that a position of the position confirmation unit and a position of the treatment catheter side depth marker are aligned when a distal end portion of the treatment catheter reaches the distal shaft. 2. The support catheter according to 2.   The support catheter according to any one of claims 1 to 3, wherein the position confirmation unit has visibility.