Medical device and treatment method

Abstract

To provide a medical device and a treatment method capable of discharging an object that has left a blood vessel or a treatment device as a result of the treatment by the treatment device to the outside of the body, and inhibiting the object from remaining inside a guiding catheter, and returning inside the blood vessel again.SOLUTION: A medical device 10 includes a treatment device 20 having a long-sized tubular shaft 21 and an outer pipe 31 into which the tubular shaft 21 is inserted. The outer pipe 31 surrounds the tubular shaft 21, forms a flow passage with an outer peripheral surface of the tubular shaft 21, has an outer diameter smaller than a proximal end side or can be reduced to an outer diameter smaller than the proximal end side, and has a tip connection part 36 that can be inserted into another tube body, at the tip.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a medical device for insertion into a blood vessel to perform treatment, and a treatment method. [Background technology]

[0002] 2. Description of the Related Art Guiding catheters are used to guide therapeutic devices, such as balloon catheters and stent placement catheters, which are inserted into blood vessels to perform treatment, diagnosis, and the like, to a target site.

[0003] For example, in percutaneous transluminal coronary angioplasty (PTCA), which is one of the PCI procedures for treating the coronary artery, a guidewire for a guiding catheter is inserted into an artery through the skin of the wrist or thigh and reaches the entrance of the coronary artery. Next, the guiding catheter is inserted into the artery along the guidewire, and then the guidewire for the guiding catheter is removed and engaged with the coronary artery opening. A thinner guidewire for a treatment device is inserted into the lumen of the guiding catheter and passed through the lesion in the coronary artery. After this, a balloon catheter is inserted along the guidewire for the treatment device, the tip of the balloon catheter is protruded from the tip opening of the guiding catheter, and the balloon is advanced to the periphery in the coronary artery along the guidewire that has passed through the lesion, and the balloon is placed at the lesion, and the balloon is inflated to perform treatment.

[0004] Incidentally, Patent Document 1 describes a device in which a tubular part connected to the tip of a linear part made of a metal wire is inserted into a guiding catheter and protruded from the tip side, and foreign bodies in a blood vessel are aspirated through a lumen connected to the guiding catheter and the tubular part. The foreign bodies aspirated from the tip opening of the tubular part are discharged to the outside from the lumen of the tubular part through the lumen of the guiding catheter. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2006-87643 A Summary of the Invention [Problem to be solved by the invention]

[0006] When a foreign body is aspirated using the device described in Patent Document 1, the foreign body may remain inside the guiding catheter. In this case, the foreign body remaining inside the guiding catheter may return to the blood vessel due to a procedure after the aspirating.

[0007] The present invention has been made to solve the above-mentioned problems, and aims to provide a medical device and a treatment method that can effectively expel objects that have detached from a blood vessel or a treatment device due to treatment with the treatment device to the outside of the body, and that can prevent the objects from remaining inside the guiding catheter and returning into the blood vessel. [Means for solving the problem]

[0008] The medical device of the present invention, which achieves the above-mentioned objective, is a medical device comprising a treatment device having a long shaft and an outer tube into which the shaft is inserted, wherein the outer tube surrounds the shaft, forms a flow path between the outer tube and the outer peripheral surface of the shaft, has an outer diameter smaller than the base end side or is capable of being reduced to an outer diameter smaller than the base end side, and is characterized in that it is equipped with a tip connection portion at its tip that can be inserted into another tubular body.

[0009] A treatment method according to the present invention for achieving the above object is a method for percutaneously treating a blood vessel, comprising the steps of: inserting a guiding catheter into a blood vessel; inserting a guide extension catheter having a tubular distal tube and a linear shaft extending from the distal tube toward the proximal end side into the guiding catheter from the proximal end side of the guiding catheter, causing a part of the distal tube to protrude toward the distal end side beyond the guiding catheter; and inserting a treatment device having a long shaft, surrounding the shaft, forming a flow path between the shaft and an outer circumferential surface, having an outer diameter smaller than the proximal end side or capable of being reduced to an outer diameter smaller than the proximal end side, into another tubular body. The method includes the steps of: inserting an outer tube having an insertable tip connecting portion at its tip into the inside of the guiding catheter from the base end side of the guiding catheter; protruding the tip of the treatment device distal to the tip tube through the inside of the tip tube and inserting the tip connecting portion into the base end opening of the tip tube; performing treatment with the treatment device; and applying suction force to the outer tube simultaneously with or after the treatment with the treatment device, and discharging any object that has detached from the blood vessel or the treatment device by the treatment to the outside through the inside of the tip tube and the outer tube. Effect of the Invention

[0010] The medical device configured as described above can be connected by inserting the distal end connection part of the outer tube into the proximal end opening of the distal end tube of the guide extension catheter having a tubular distal end tube fixed to the distal end of the long linear shaft. Therefore, a treatment is performed in a blood vessel using a treatment device that penetrates the distal end tube and protrudes distally beyond the distal end tube, and an object that has become detached from the blood vessel or the treatment device due to the treatment can be discharged to the outside using the distal end tube and the lumen of the outer tube of the connected guide extension catheter. Therefore, this medical device can effectively discharge an object that has become detached from the blood vessel or the treatment device due to the treatment by the treatment device to the outside of the body, and can prevent the object from remaining inside the guiding catheter and returning to the blood vessel again.

[0011] The treatment method configured as described above can discharge objects detached from a blood vessel or a treatment device by treatment to the outside by utilizing the lumen of the distal tube and the outer tube of the connected guide extension catheter. Therefore, this treatment method can effectively discharge objects detached from a blood vessel or a treatment device by treatment with a treatment device to the outside of the body, and can prevent the objects from remaining inside the guiding catheter and returning to the blood vessel.

[0012] The outer tube may be part of an outer catheter having an outer hub with a suction connection part connected to a proximal end of the outer tube and capable of connecting a suction power supply part for supplying suction power, whereby objects that become detached from a blood vessel or a treatment device during treatment can be expelled to the outside through the suction connection part of the outer hub of the outer catheter.

[0013] The outer hub may have a main passage through which the shaft can pass, and a branch passage branching from the main passage and opening to the outside at the suction connection part, and a valve body slidable along the shaft may be disposed on the base end side of the branch part of the main passage with the branch passage. In this way, when suction force is applied to the main passage from the suction connection part of the outer hub via the branch passage, the valve body prevents pressure from leaking from the main passage to the base end side, and suction force can be effectively applied to the tip side of the outer tube.

[0014] The treatment device may have an expandable / contractable balloon at the distal end of the shaft, whereby an object that has been removed from a blood vessel by treatment using the balloon can be discharged to the outside from the suction connection part of the outer hub by using the lumen of the distal tube and the outer tube of the guide extension catheter.

[0015] The medical device may have a guide extension catheter having a tubular distal tube and a linear shaft extending from the distal tube to the proximal end, the distal tube having a distal lumen through which the treatment device can pass, a proximal end opening that opens to the outside is formed at the proximal end of the distal lumen, and the distal connection part of the outer catheter may be insertable in close contact with the proximal end opening. This makes it difficult for pressure to leak between the distal tube and the outer tube, and therefore the medical device can improve suction efficiency.

[0016] The outer tube may have a groove formed on its outer circumferential surface along the axial direction of the outer tube, whereby the medical device allows the linear shaft of a guide extension catheter used together with the outer tube to be stably positioned in the groove of the outer tube, thereby enabling stable suction. [Brief description of the drawings]

[0017] [Figure 1] FIG. 1 is a plan view showing a medical device according to an embodiment of the present invention. [Diagram 2] 1 is a cross-sectional view showing a state in which the medical device according to the embodiment is inserted into a guiding catheter. [Diagram 3] 3A and 3B are views showing a state in which a medical device is inserted into a guiding catheter, where (A) is a cross-sectional view taken along line AA in FIG. 2, and (B) is a cross-sectional view taken along line BB in FIG. [Figure 4]1A is a cross-sectional view for explaining a state in which a medical device according to an embodiment of the present invention is used, and FIG. 1B is a cross-sectional view showing a state in which a guide extension catheter is inserted into a guiding catheter, and FIG. 1B is a cross-sectional view showing a state in which a medical device is inserted into a guiding catheter. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Note that the dimensional ratios in the drawings may be exaggerated for the sake of explanation and may differ from the actual ratios. In this specification, the side of the device that is inserted into the blood vessel is referred to as the "distal side" and the side that is operated is referred to as the "base side".

[0019] 1 to 3, a medical device 10 having an intermediate opening according to this embodiment is inserted into a guiding catheter 100 to treat a lesion and discharge matter resulting from the treatment. The medical device 10 includes a treatment device 20 having a long tubular shaft 21, an outer catheter 30 having an outer tube 31 surrounding the tubular shaft 21, and a guide extension catheter 40 having a distal end tube 41 into which the tubular shaft 21 can be inserted.

[0020] The guiding catheter 100 is a catheter equipped with a long tubular body for guiding the treatment device 20 to a predetermined position in a blood vessel, and has a catheter tip opening 101 .

[0021] The guide extension catheter 40 is used to extend a tube for guiding the treatment device 20 to a predetermined position in a blood vessel from the guiding catheter 100. The guide extension catheter 40 is inserted, for example, from the catheter tip opening 101 of the guiding catheter 100 placed in a blood vessel to a curved or bent coronary artery to a lesion, and provides a lumen for smoothly reaching the treatment device 20 to the lesion.

[0022] The guide extension catheter 40 comprises a tubular tip tube 41, a linear shaft 42 connected to the tip tube 41 and extending from the tip tube 41 to the base end side, and a gripping portion 46 to which the base end of the linear shaft 42 is fixed.

[0023] The distal tube 41 is a flexible tube having a distal lumen 43 penetrating from the distal end to the proximal end. A proximal end opening 44 is formed at the proximal end of the distal tube 41, where the distal lumen 43 opens. A distal end opening 45 is formed at the distal end of the distal tube 41, where the distal lumen 43 opens. The proximal end of the distal tube 41 is formed at an incline with respect to the axis X of the distal tube 41, and the proximal end opening 44 is also formed at an incline. Therefore, the proximal end of the distal tube 41 is formed in a half-pipe shape that opens to the side (in a direction perpendicular to the axis X). The distal tube 41 can move through the lumen of the guiding catheter 100 and protrude from the catheter distal end opening 101 of the guiding catheter 100 to the distal side. That is, in the procedure, the distal tube 41 of the guide extension catheter 40 is inserted closer to the lesion than the guiding catheter 100, and can provide a stable backup for the treatment device 20. Furthermore, the distal tube 41 receives a suction force from the base end side and can suck an object from the distal opening 45. The distal tube 41 is formed of a resin material. The material constituting the distal tube 41 is not particularly limited, but is preferably, for example, a resin material or a resin material containing a metal reinforcing wire for reinforcement.

[0024] The linear shaft 42 is a flexible wire that is connected to the distal tube 41 and extends from the distal tube 41 to the proximal end side. The material of the linear shaft 42 is not particularly limited, but is preferably, for example, stainless steel, a nickel-titanium alloy, or the like.

[0025] The base end of the linear shaft 42 is fixed to the grip portion 46. The grip portion 46 is a portion that allows the surgeon to easily grasp and operate the device.

[0026] In this embodiment, the therapeutic device 20 is a balloon catheter, and comprises a long tubular shaft 21, a hub 22 fixed to the base end of the tubular shaft 21, and a balloon 23 fixed to the tip end of the tubular shaft 21.

[0027] The tubular shaft 21 comprises an outer tubular shaft 24, which is a tubular body with open distal and proximal ends, and an inner tubular shaft 25 disposed inside the outer tubular shaft 24. The outer tubular shaft 24 has an expansion lumen 26 formed therein through which an expansion fluid for expanding the balloon 23 flows, and the inner tubular shaft 25 has a guidewire lumen 27 formed therein through which a guidewire 120 is inserted.

[0028] The tip of the inner tubular shaft 25 penetrates the inside of the balloon 23 and opens further distal than the balloon 23, and the base end penetrates the side wall of the outer tubular shaft 24 and is liquid-tightly fixed to the outer tubular shaft 24 by adhesive or heat fusion.

[0029] The hub 22 has an expansion opening 28 that communicates with the expansion lumen 26 of the outer tubular shaft 24 and functions as a port for the inflow and outflow of expansion fluid. The hub 22 has a proximal end of the outer tubular shaft 24 secured thereto.

[0030] The balloon 23 has a distal end fixed to the inner tubular shaft 25 and a proximal end fixed to the outer tubular shaft 24, and the inside of the balloon 23 communicates with the expansion lumen 26. The balloon 23 can be expanded radially outward by being supplied with fluid from the expansion lumen 26, and can be contracted radially inward by discharging fluid to the expansion lumen 26. A fat-soluble compound including a fat-soluble drug is disposed on the outer surface of the balloon 23, but the fat-soluble compound does not have to be disposed, and a medicinal solution may leak from inside the balloon 23 through pores provided in the balloon 23.

[0031] The outer catheter 30 has an outer tube 31 that surrounds the tubular shaft 21 of the treatment device 20 , an outer hub 32 fixed to the proximal end of the outer tube 31 , and a valve body 33 disposed within the outer hub 32 .

[0032] The outer tube 31 is a flexible tubular body. The outer tube 31 has an outer tube base end 34 fixed to the outer hub 32, an outer tube central portion 35 disposed on the tip side of the outer tube base end 34, and a tip connection portion 36 disposed at the tip of the outer tube 31 and connectable to a tip tube 41. The outer tube base end 34 is in the shape of a circular tube and fixed to the outer hub 32. The outer catheter 30 may be, for example, only the outer tube 31, or may be a combination of the outer tube 31 with a Y connector attached to its base end, or a hub with a detachable branch port attached to its base end.

[0033] A groove 37 is formed on the outer circumferential surface of the outer tube central portion 35 along the axial direction X of the outer tube 31. The groove 37 is capable of accommodating at least a part of the linear shaft 42 of the guide extension catheter 40. Alternatively, there may be no groove and the groove may be deformed along the linear shaft 42 of the guide extension catheter 40, or a peel-away weakened portion may be provided along the entire length along the X axis so that the outer tube 31 can be easily removed after use.

[0034] The tip connection part 36 has an inner diameter and an outer diameter smaller than those of the outer tube central part 35. The outer tube 31 preferably has a portion where the inner diameter and the outer diameter gradually decrease from the outer tube central part 35 toward the tip connection part 36. The outer diameter of the tip connection part 36 is slightly smaller than the inner diameter of the tip tube 41. This allows the tip connection part 36 to be inserted into the base end opening 44 of the tip tube 41 of the guide extension catheter 40 and to be in close contact with the tip lumen 43. This makes it possible to suppress pressure leakage between the tip tube 41 and the outer tube 31. The tip connection part 36 preferably has a length equal to or greater than the length L in the axial direction X so that it can be inserted without any gap into the base end opening 44 having a length L (see FIG. 2) in the axial direction X.

[0035] Alternatively, the portion inserted into the base end opening 44 may be tapered, and the tapered portion which is smaller than the inner diameter of the tip tube 41 of the guide extension catheter 40 may be in close contact with the tip lumen 43 or the base end opening 44, and the outer diameter of the tip connection part 36 on the base end side may be larger than the inner diameter of the tip tube 41, or the shape may be an inverted figure-8 in which the outer diameter is larger only on the half pipe opening side (the side which is partially open).

[0036] In this embodiment, the distal end connection part 36 of the outer tube 31 has an outer diameter smaller than that of the outer tube central part 35 and the outer tube base end part 34, which are located proximal to the distal end of the distal end connection part 36 of the outer tube 31. However, the distal end connection part 36 may not have an outer diameter smaller than that of the outer tube central part 35 and the outer tube base end part 34, and may have an outer diameter similar to that of the outer tube central part 35 and the outer tube base end part 34. In this case, it becomes easy to insert the treatment device 20 into the outer tube 31. If the distal end connection part 36 of the outer tube 31 is shrinkable, the distal end connection part 36 can be shrinked after the treatment device 20 is inserted into the outer tube 31 and the balloon 23 arranged at the distal end of the treatment device 20 is protruded from the distal end opening of the distal end connection part 36. If the outer tube 31 is formed of, for example, a heat shrink tube, the distal end part of the outer tube 31 can be heated after the treatment device 20 is inserted into the outer tube 31, and the distal end connection part 36 of the outer tube 31 can be shrinked in diameter. The heat shrink tube is, for example, a heat shrinkable single-layer tube having a thickness of about 0.1 mm, and may be peel-away so that the outer tube 31 can be easily removed after use.

[0037] The outer hub 32 has a main passage 38 that communicates with the lumen of the outer tube 31 and penetrates in the extension direction of the outer tube 31, and a branch passage 39 that branches off from the main passage 38 and opens at a suction connection part 39A on the side. The valve body 33 is disposed on the base end side of the branch part of the main passage 38 with the branch passage 39. The suction connection part 39A can be connected to a suction force supply part (e.g., a tube) that supplies suction force (negative pressure) from a suction source such as a pump. The outer hub 32 does not need to have the branch passage 39 and the valve body 33. In this case, the outer hub 32 may be connected to a Y connector having a branch passage and the valve body 33 at the opening of the main passage 38.

[0038] Next, a method of using the medical device 10 according to this embodiment will be described.

[0039] The surgeon inserts a guide wire for the guiding catheter 100 percutaneously into the femoral artery, radial artery, etc., and pushes the guiding catheter 100 along the guide wire, for example, to hook and engage the tip of the guiding catheter 100 with the coronary artery opening of the ascending aorta. Next, the surgeon removes the guide wire for the guiding catheter 100, inserts a thinner guide wire 120 from the opening on the base end side of the guiding catheter 100, and inserts it into the coronary artery from the catheter tip opening 101 of the guiding catheter 100. Next, the surgeon inserts the guide extension catheter 40, with the base end of the guide wire 120 inserted into the tip lumen 43, into the opening on the base end side of the guiding catheter 100 and pushes it forward, causing it to protrude toward the tip from the catheter tip opening 101 of the guiding catheter 100, and inserts it into the coronary artery. Next, as shown in FIG. 4(A), the surgeon advances the guide extension catheter 40 while leading the guide wire 120, until the guide extension catheter 40 reaches the vicinity of the stenosed lesion.

[0040] Next, the operator inserts the proximal end of the guidewire 120 into the guidewire lumen 27 of the treatment device 20. At this time, the treatment device 20 is inserted into the outer catheter 30. Next, as shown in FIG. 2, the operator inserts the treatment device 20 and the outer catheter 30 into the proximal end opening 44 of the guiding catheter 100 and pushes them forward, and inserts them into the proximal end opening 44 of the distal end tube 41 of the guide extension catheter 40 arranged inside the guiding catheter 100. The treatment device 20 passes through the distal end lumen 43 of the distal end tube 41 and reaches the vicinity of the lesion of the coronary artery from the distal end opening 45 of the distal end tube 41. After this, the operator places the balloon 23 inside the stenotic lesion. Next, while maintaining the position of the treatment device 20, the operator moves the outer catheter 30 in the distal direction, and inserts the distal end of the outer catheter 30 into the proximal end opening 44 of the distal end tube 41. As a result, the distal end of the outer catheter 30 is inserted into and tightly attached to the proximal opening 44 of the distal tube 41. At this time, it is preferable that the proximal opening 29 of the guidewire lumen 27 of the treatment device 20 is located closer to the proximal end than the proximal opening 44 of the distal tube 41. This makes it possible to prevent the guidewire 120 from being drawn out from the proximal opening 29 of the treatment device 20 into the small gap between the distal lumen 43 and the outer circumferential surface of the treatment device 20.

[0041] Next, the surgeon connects a suction force supplying part such as a tube connected to a suction source such as a pump to the branch passage 39 of the outer hub 32. After that, the surgeon operates the suction source to start suction, while connecting an inflator or the like to the expansion opening 28 of the treatment device 20 to supply expansion fluid. As a result, as shown in FIG. 4(B), the expansion fluid moves through the expansion lumen 26 into the balloon 23, expanding the balloon 23. Therefore, the lesion is pushed open by the balloon 23. When the lesion is pushed open by the balloon 23, thrombus, plaque, calcified lesion, etc. forming the lesion may detach from the blood vessel. In addition, when the balloon 23 is a drug-coated balloon (DCB), when the lesion is pushed open, excess lipophilic compounds (including lipophilic drugs and lipophilic solids) etc. may detach from the balloon 23. At this time, the suction force from the suction source acts on the tip opening 45 through the lumen of the outer tube 31 and the tip tube 41. Therefore, an object that has detached from a diseased part of a blood vessel or the treatment device 20 (particularly the balloon 23) is sucked into the distal lumen 43 from the distal opening 45 of the distal tube 41, passes through the lumen of the outer tube 31, the main passage 38, and the branch passage 39, and is discharged to the outside from the suction connection part 39A. At this time, the valve body 33 arranged in the main passage 38 of the outer hub 32 is arranged on the base end side of the branch part of the main passage 38 with the branch passage 39, so that the suction force can be prevented from leaking to the base end side of the outer hub 32. Therefore, the suction force acting on the branch passage 39 can be efficiently transmitted to the distal opening 45.

[0042] The surgeon expands the lesion with the balloon 23 and then contracts the balloon 23. Next, the surgeon stops the suction by the suction source, but may continue the suction to remove plaque or calcified lesions, fat-soluble compounds (including fat-soluble drugs and fat-soluble solids), and the like remaining on the peripheral side of the balloon 23. After this, the surgeon removes the treatment device 20 and the outer catheter 30 from the body. Since the object sucked from the distal end opening 45 of the distal end tube 41 during suction is discharged to the outside through the distal end lumen 43 and the lumen of the outer tube 31, the sucked object is unlikely to remain inside the guiding catheter 100. Therefore, during the procedure using the guiding catheter 100 that is performed after this, it is possible to suppress the sucked object from returning to the blood vessel again.

[0043] As described above, the medical device 10 of this embodiment is a medical device 10 having a treatment device 20 having a long tubular shaft 21, and an outer tube 31 into which the tubular shaft 21 is inserted, where the outer tube 31 surrounds the tubular shaft 21, forms a flow path between the outer tube 31 and the outer surface of the tubular shaft 21, has an outer diameter smaller than the base end side or is capable of being reduced to an outer diameter smaller than the base end side, and has a tip connection portion 36 at its tip that can be inserted into another tubular body.

[0044] As a result, the medical device 10 can be connected by inserting the tip connection part 36 of the outer tube 31 into the base end opening 44 of the tip tube 41 of the guide extension catheter 40, which has a tubular tip tube 41 fixed to the tip of a long linear shaft 42. Therefore, a treatment is performed in a blood vessel by the treatment device 20 that penetrates the tip tube 41 and protrudes further to the tip side than the tip tube 41, and an object that has become detached from the blood vessel or the treatment device 20 due to the treatment can be discharged to the outside from the suction connection part 39A of the outer hub 32 using the lumen of the tip tube 41 and the outer tube 31 of the connected guide extension catheter 40. Therefore, the medical device 10 can effectively discharge an object that has become detached from the blood vessel or the treatment device 20 due to the treatment by the treatment device 20 to the outside of the body, and can suppress the object from remaining inside the guiding catheter 100 and returning to the blood vessel again.

[0045] The outer tube 31 is a part of the outer catheter 30 having an outer hub 32 with a suction connection part 39A connected to the base end of the outer tube 31 and capable of connecting a suction power supply part that supplies suction power. This allows an object that has become detached from a blood vessel or a treatment device during treatment to be discharged to the outside from the suction connection part 39A of the outer hub 32 of the outer catheter 30.

[0046] The outer hub 32 has a main passage 38 through which the tubular shaft 21 can pass, a branch passage 39 that branches off from the main passage 38 and opens to the outside at a suction connection 39A, and a valve body 33 that can slide along with the tubular shaft 21 is disposed on the base end side of the branch point of the main passage 38 with the branch passage 39. As a result, when a suction force is applied to the main passage 38 from the suction connection 39A of the outer hub 32 via the branch passage 39, the valve body 33 prevents pressure from leaking from the main passage 38 to the base end side, and the suction force can be effectively applied to the tip side of the outer tube 31.

[0047] The treatment device 20 has an expandable and contractable balloon 23 at the tip of the tubular shaft 21. This allows an object that has been removed from a blood vessel by treatment using the balloon 23 to be discharged to the outside from the suction connection part 39A of the outer hub 32 using the tip tube 41 of the guide extension catheter 40 and the lumen of the outer tube 31.

[0048] The medical device 10 has a guide extension catheter 40 having a tubular distal tube 41 and a linear shaft 42 extending from the distal tube 41 to the proximal end side, the distal tube 41 has a distal lumen 43 through which the treatment device 20 can pass, and a proximal opening 44 that opens to the outside is formed at the proximal end of the distal lumen 43, and the distal connection part 36 of the outer tube 31 can be inserted in close contact with the proximal opening 44. This makes it difficult for pressure to leak between the distal tube 41 and the outer tube 31 in the medical device 10. This allows the medical device 10 to improve suction efficiency.

[0049] The outer tube 31 has a groove 37 formed on the outer peripheral surface along the axial center X direction of the outer tube 31. This allows the medical device 10 to stably position the linear shaft 42 of the guide extension catheter 40 used together with the outer tube 31 in the groove 37 of the outer tube 31, thereby enabling stable suction.

[0050] Furthermore, the treatment method in this embodiment is a method for percutaneously treating a blood vessel, and includes the steps of inserting a guiding catheter 100 into a blood vessel, inserting a guide extension catheter 40 having a tubular distal end tube 41 and a linear shaft 42 extending from the distal end tube 41 toward the proximal end side into the inside of the guiding catheter 100 from the proximal end side of the guiding catheter 100 so that a part of the distal end tube 41 protrudes toward the distal end side beyond the guiding catheter 100, and inserting a treatment device 20 having a long tubular shaft 21 into the guiding catheter 100. The treatment device 20 surrounds the tubular shaft 21, forms a flow path between the tubular shaft 21 and the outer peripheral surface of the tubular shaft 21, and has an outer diameter smaller than the proximal end side or is reduced in diameter to a smaller outer diameter than the proximal end side. the step of inserting the guiding catheter 100 from the base end side of the guiding catheter 100 together with an outer tube 31 having a tip connecting portion 36 at its tip that can be inserted into another tubular body; the step of protruding the tip of the therapeutic device 20 through the inside of the tip tube 41 and further distal than the tip tube 41, and inserting the tip connecting portion 36 into the base end opening 44 of the tip tube 41; the step of performing treatment using the therapeutic device 20; and the step of applying suction force to the outer tube 31 simultaneously with or after the treatment using the therapeutic device 20, and discharging any object that has detached from the blood vessel or the therapeutic device 20 due to the treatment to the outside through the inside of the tip tube 41 and the outer tube 31.

[0051] The treatment method configured as described above can discharge an object detached from a blood vessel or the treatment device 20 by treatment to the outside by utilizing the lumen of the distal tube 41 and the outer tube 31 of the connected guide extension catheter 40. Therefore, this treatment method can effectively discharge an object detached from a blood vessel or the treatment device 20 by treatment with the treatment device 20 to the outside of the body, and can prevent the object from remaining inside the guiding catheter 100 and returning to the blood vessel again.

[0052] The present invention is not limited to the above-mentioned embodiment, and various modifications can be made by those skilled in the art within the technical concept of the present invention. For example, the treatment device 20 in this embodiment is a rapid exchange type in which the guidewire lumen 27 is disposed only at the tip of the tubular shaft 21, but it may be an over-the-wire type in which the guidewire lumen is formed from the tip to the base end of the shaft. In addition, the treatment device is not particularly limited as long as it is a device used for treatment in a blood vessel. For example, the treatment device may be a stent placement catheter in which a stent is disposed on the outer circumferential surface of a balloon, a stent placement catheter for placing a self-expanding stent in a blood vessel, a cutting balloon catheter in which a blade is disposed on the outer circumferential surface of a balloon, an atherectomy device for mechanically cutting a lesion, etc. [Explanation of symbols]

[0053] 10 Medical Devices 20 Therapeutic Devices 30 Outer Catheter 31 Outer tube 32 Outer hub 33 Valve body 36 Tip connection part 37 Groove 38 Main passage 39 Branch Passage 39A Suction Connection 40 Guide Extension Catheter 41 Tip tube 42 Linear Shaft 43 Tip Lumen 44 Proximal opening 45 Tip opening 100 Guiding catheter 101 Catheter tip opening 120 Guidewire X-axis center

Claims

1. A treatment device having a long shaft; an outer tube into which the shaft is inserted; A medical device characterized in that the outer tube surrounds the shaft, forms a flow path between the outer tube and the outer peripheral surface of the shaft, has an outer diameter smaller than that of the base end side or is capable of being reduced to an outer diameter smaller than that of the base end side, and is equipped with a tip connection portion at its tip that can be inserted into another tubular body.

2. The medical device of claim 1, wherein the outer tube is part of an outer catheter having an outer hub connected to a proximal end of the outer tube and having a suction connection to which a suction supply unit for supplying suction can be connected.

3. the outer hub has a main passage through which the shaft can pass, and a branch passage branching from the main passage and opening to the outside at the suction connection portion, The medical device according to claim 1 or 2, characterized in that a valve body slidable along the shaft is disposed on the proximal side of the branching portion of the main passage with the branch passage.

4. The medical device according to any one of claims 1 to 3, characterized in that the treatment device has an expandable and contractable balloon at the tip of the shaft.

5. a guide extension catheter having a tubular distal tube and a linear shaft extending from the distal tube to a proximal end side; The distal tube has a distal lumen through which the treatment device can penetrate, and a proximal end opening that opens to the outside is formed at the proximal end of the distal lumen, The medical device according to any one of claims 1 to 4, characterized in that the tip connection portion of the outer tube is capable of being inserted into the base end opening in close contact therewith.

6. 6. The medical device according to claim 1, wherein the outer tube has a groove formed on an outer peripheral surface thereof along an axial direction of the outer tube.

7. A method for percutaneously treating a blood vessel, comprising: Inserting a guiding catheter into a blood vessel; a guide extension catheter having a tubular distal tube and a linear shaft extending from the distal tube to a proximal end side, inserted into the guiding catheter from a proximal end side of the guiding catheter, and a part of the distal tube protruding beyond the guiding catheter; a step of inserting a treatment device having a long shaft into the inside of the guiding catheter from the base end side of the guiding catheter together with an outer tube that surrounds the shaft, forms a flow path between the outer tube and an outer peripheral surface of the shaft, has an outer diameter smaller than that of the base end side or can be reduced to an outer diameter smaller than that of the base end side, and has a tip connection part at its tip that can be inserted into another tube; a step of protruding a tip of the treatment device through an inside of the tip tube toward a tip side beyond the tip tube and inserting the tip connection part into a base end opening of the tip tube; performing a treatment using the treatment device; and applying suction force to the outer tube simultaneously with or after treatment with the treatment device, thereby discharging any object that has detached from the blood vessel or the treatment device due to the treatment to the outside through the tip tube and the inside of the outer tube.

8. The method of claim 7, wherein the outer tube is part of an outer catheter having an outer hub connected to a proximal end of the outer tube and equipped with a suction connection to which a suction supply unit for supplying suction can be connected.

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