JP3828958B2 - Balloon catheter - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a balloon catheter.
[0002]
[Prior art]
Conventionally, as a balloon catheter used in IABP (intra-aortic balloon pumping), a balloon that can be expanded / contracted by helium gas supplied and discharged inside, and a distal end side of this balloon are joined to the rear end of the balloon. An outer tube capable of supplying and discharging helium gas via a lumen communicating with the inside, and an outer tube and an inner tube penetrating the inside of the balloon from the proximal end side of the outer tube to the tip of the balloon A so-called double lumen type is also known.
[0003]
[Problems to be solved by the invention]
By the way, when the conventional balloon catheter is inserted into a blood vessel, a certain amount of resistance is applied to the distal end side of the balloon. When such resistance is applied, the inner tube is bent in the outer tube. It was sometimes pushed back slightly toward the proximal end. In this state, the balloon is crushed in the axial direction as much as the tip end of the balloon folded around the inner tube and the distal end of the outer tube approach each other. There has been a problem that the diameter is increased, and insertion into the blood vessel and guidance within the blood vessel are difficult.
[0004]
Here, if the relative displacement between the outer tube and the inner tube is simply prevented, the entire inner tube is bonded, fused or integrally formed, for example, as a balloon catheter described in JP-A-5-123403. It may be fixed to the inner wall of the outer tube by such means. However, in the case of a structure like that described in the publication, the outer tube and the inner tube cannot move relative to each other, so the flexibility of the tube is inevitably lost. Since the cross-sectional shape is not a rotationally symmetric shape, directionality occurs in the flexibility of the tube, for example, it can be bent relatively flexibly in a specific direction, but it is difficult to bend in another specific direction. Invited, there is a problem that the operability in the blood vessel that irregularly meanders deteriorates.
[0005]
The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a balloon catheter in which the balloon does not sag when inserted into a blood vessel and the flexibility of the catheter is not impaired. There is.
[0006]
[Means for Solving the Problems and Effects of the Invention]
In order to achieve the above-mentioned object, the present invention is as described in claim 1.
A balloon that can be expanded / contracted by a fluid supplied to and discharged from the inside, and an outer side in which a distal end side is joined to a rear end portion of the balloon and the fluid can be supplied and discharged through a lumen communicating with the inside of the balloon In a balloon catheter comprising a tube and an inner tube penetrating the outer tube and the inside of the balloon from the proximal end side of the outer tube to the tip of the balloon,
The distal end of the outer tube has a shape in which only a part of the entire circumference of the outer tube is left and parts other than the part are removed, and the shaped part is arranged inside the balloon. By joining the outer tube and the balloon as described above , a projecting portion formed by extending only the portion of the outer tube into the balloon is formed at the distal end of the outer tube. The inner tube is fixed.
[0007]
According to the balloon catheter of the present invention, since the inner tube is fixed to the outer tube at the distal end portion of the outer tube, when the balloon catheter is inserted into the blood vessel, it resists the tip side of the balloon. Even if force is applied, the inner tube is not pushed back into the outer tube. Therefore, the balloon is not squeezed and sagging in the axial direction, and insertion into the blood vessel and guidance within the blood vessel become smoother than before.
[0008]
In addition, since the outer tube and the inner tube are only fixed at the distal end of the outer tube, there is a certain degree of freedom in the positions that the inner tube can take in the outer tube at other points. If the tube is bent, the inner tube freely escapes to a position where stress is most relaxed, so that the flexibility of the catheter is not impaired. In particular, unlike the case where the entire inner tube is fixed to the inner wall of the outer tube, the directivity that it is difficult to bend only in a specific direction does not appear, so that the operability in the irregularly meandering blood vessel is not impaired.
[0009]
Furthermore, in the balloon catheter of the present invention, the distal end of the outer tube has a shape in which only a part of the entire circumference of the outer tube is left and a part other than the part is removed. By connecting the outer tube and the balloon so that the outer tube and the balloon are disposed inside the balloon, a protruding portion formed by extending only the portion of the outer tube into the balloon is provided at the distal end of the outer tube. Since the inner tube is fixed to the protruding portion, the inner tube is fixed to the protruding portion exposed to the outside without fixing the inner tube to the inner wall of the outer tube. Since it is only necessary to fix the tube, for example, it is easy to apply an adhesive, and the outer part of the inner tube is exposed to the outside of the fixed part. Runode, and pressed against the inner tube in the fixing portion, can be easily implemented that such encouraging adhesion or fusion.
[0010]
As described in claim 2 ,
When the overhanging portion has flexibility capable of bending by flexibly elastically deforming together with the inner tube,
When the tube is bent in the vicinity of the fixed part (overhanging part), the overhanging part bends, so that the inner tube is not bent at the part that goes out of the opening on the distal end side of the outer tube. Therefore, the lumen of the inner tube is not crushed and the guidance in the blood vessel is smooth.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Next, embodiments of the present invention will be described with reference to the drawings. In addition, the balloon catheter demonstrated below is only an example of embodiment of this invention, and the structure means of this invention is not limited to the following example at all.
[0012]
The balloon catheter 1 for IABP is of a well-known double lumen type, and includes a balloon 2, an outer tube 4, an inner tube 6, a tip tip 8, and a Y connector 10 as shown in FIG. The gap between the inner peripheral surface of the outer tube 4 and the outer peripheral surface of the inner tube 6 communicates with the inflation port 12 of the Y connector 10 on the proximal end side, and communicates into the balloon 2 on the distal end side. A supply / exhaust path capable of supplying helium gas supplied from the deflation port 12 to the balloon 2 is formed. On the other hand, the lumen of the inner tube 6 communicates with the guide wire port 14 of the Y connector 10 on the proximal end side, and communicates with the opening 16 at the distal end of the tip tip 8 on the distal end side. A passage through which a guide wire inserted and placed in the blood vessel can be inserted is formed. Although the outer tube 4 and the inner tube 6 are partially broken and not shown in the drawings, they are actually long ones having the same shape.
[0013]
As a characteristic configuration of the balloon catheter 1, a protruding portion 20 is formed by extending a part of the outer tube 4 into the balloon 2 at the distal end portion of the outer tube 4. The inner tube is secured. As shown in FIG. 2, the projecting portion 20 is a tongue-shaped projecting object formed integrally with the outer tube 4, and the inner tube 6 and the projecting portion 20 are formed by an adhesive 22 interposed therebetween. It is fixed. Further, the overhanging portion 20 has flexibility that can be flexibly elastically deformed and bent together with the inner tube 6, and when the outer tube 4 and the inner tube 6 are bent in the vicinity of the overhanging portion 20, the overhanging portion 20. Is bent to prevent the inner tube 6 from being bent sharply.
[0014]
According to the balloon catheter 1 configured as described above, the inner tube 6 is fixed to the overhanging portion 20 which is a part of the outer tube 4 at the distal end portion of the outer tube 4. When inserting into the blood vessel, the inner tube 6 is not pushed back in the outer tube 4 even if a resistance force is applied to the tip 8 or the like. Therefore, the balloon 2 is not squeezed and sagging in the axial direction, and insertion into the blood vessel and guidance within the blood vessel become smoother than the conventional product.
[0015]
Further, since the outer tube 4 and the inner tube 6 are only fixed at the distal end portion of the outer tube 4, the inner tube 6 freely changes its relative position in the outer tube 4 at other points. be able to. Therefore, if the double tube portion composed of the outer tube 4 and the inner tube 6 is curved, the inner tube 6 freely escapes to a position where stress is most relaxed, so that the flexibility of the balloon catheter 1 is not impaired. . In particular, unlike the case where the entire inner tube 6 is fixed to the inner wall of the outer tube 4, there is no directivity that it is difficult to bend only in a specific direction, and this may impair the operability in irregularly meandering blood vessels. Absent.
[0016]
Although the embodiment of the present invention has been described above, various means other than the balloon catheter 1 can be considered as the constituent means of the present invention.
[0017]
For example, in the balloon catheter 1, but had been provided with a projecting portion 20 of such a shape shown in FIG. 2, the shape and size of the protruding portion is not limited to any one example above, substantially longitudinal center of the balloon There are various types such as a protruding part with a length that reaches the vicinity of the part, a protruding part with a thickness dimension different from the thickness of the outer tube, a protruding part with a square tip or a rounded tip. Design changes are possible.
[0018]
In addition, although the balloon catheter 1 has been described for IABP, a balloon catheter having a similar structure is also used in other treatments (for example, PTCA). By adopting the structure, it is possible to prevent balloon sagging without impairing flexibility.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a balloon catheter as an example of the present invention.
FIG. 2 is a perspective view showing a structure in the vicinity of an overhang portion.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Balloon catheter, 2 ... Balloon, 4 ... Outer tube, 6 ... Inner tube, 8 ... Tip tip, 10 ... Y connector, 12 ... Inflation port, 14 ... guide wire port, 16 ... opening, 20 ... overhang, 22 ... adhesive.

Claims (2)

A balloon that can be expanded / contracted by a fluid supplied to and discharged from the inside, and an outer side in which a distal end side is joined to a rear end portion of the balloon and the fluid can be supplied and discharged through a lumen communicating with the inside of the balloon In a balloon catheter comprising a tube and an inner tube penetrating the outer tube and the inside of the balloon from the proximal end side of the outer tube to the tip of the balloon,
The distal end of the outer tube has a shape in which only a part of the entire circumference of the outer tube is left and parts other than the part are removed, and the shaped part is arranged inside the balloon. By joining the outer tube and the balloon as described above , a projecting portion formed by extending only the portion of the outer tube into the balloon is formed at the distal end of the outer tube. A balloon catheter having the inner tube fixed thereto. The balloon catheter according to claim 1,
The balloon catheter is characterized in that the overhanging portion is flexible and elastically deformable and bendable together with the inner tube.

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