JPH0838609A - Balloon catheter for medical treatment - Google Patents

Abstract

PURPOSE:To substantially prevent slip-off of the balloon of a balloon catheter provided with the balloon at the front end of a catheter tube body from the inside of a blood vessel by providing the outside surface of the balloon with net-like projecting lines which do not intersect orthogonally with the central axial line of the catheter tube body over the entire part thereof. CONSTITUTION:The front end of the catheter tube body 1 consisting of silicone rubber, etc., is provided with the balloon 2 and the net-like projecting lines 3 which do not intersect orthogonally with the central axial line C of the catheter tube body 1 over the entire part of the outside surface of this balloon 2. The net-like projecting lines 3 have first parts 3a which are inclined to a sharp angle toward the front side with the central axial line C of the body 1 and are arranged in a plurality at prescribed intervals and second part 3b which are inclined to a sharp angle toward the front side with the central axial line C of the body 1 so as to intersect with these parts 3a and are arranged in a plurality at prescribed intervals. As a result, the contact friction resistance with the inside wall of the blood vessel is increased and the slip-off of the balloon from the inside of the blood vessel is substantially prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a balloon catheter used for medical treatment, for example, a catheter suitable for fixing a balloon placed in a blood vessel.

[0002]

2. Description of the Related Art In cardiovascular surgery such as coronary artery bypass surgery, the blood flow in the heart is stopped and the operation is performed using an artificial heart-lung machine.
Myocardium is moving in the heart, and it is necessary to protect the myocardium during such an operation. For the purpose of protecting the myocardium, a balloon provided at the tip of the catheter tube body of the balloon catheter is placed at the entrance of the coronary sinus, and the myocardial protective liquid is circulated throughout the heart while injecting the myocardial protective liquid. By doing so, even if the heart is stopped for several hours, the myocardium can continue the metabolism and the surgery can be performed with peace of mind. Due to the necessity of surgery, this balloon catheter needs to be placed at an appropriate position in a blood vessel. The balloon placed in the blood vessel is fixedly placed by contact friction with the inner wall of the blood vessel, but if the outer surface of the balloon is smooth, it is difficult to place the balloon securely in the blood vessel, or it deviates from the target site of the blood vessel, or The balloon catheter itself may fall out of the blood vessel, which is very dangerous. Moreover, physiologically, if the balloon can be indwelled at a low pressure, the damage to the blood vessel wall is minimal, which is the best, but it naturally becomes easier to deviate from the blood vessel.

In view of the above, a balloon catheter having a small rib or the like on the outer surface of the balloon has been proposed in order to increase the contact frictional resistance with the inner wall of the blood vessel (see FIGS. 5 and 6). . The outer surface of the balloon 51 of the balloon catheter of FIG. 5 has a triangular cross section and a long and narrow linear rib.
A plurality of 52 are intermittently provided in a plurality of rows on the circumference of the central portion in a direction orthogonal to the central axis of the catheter tube main body 53. On the outer surface of the balloon 61 of the balloon catheter shown in FIG. 6, a small cylindrical protrusion 62 is also formed as a rib.
Similar to 52, a plurality of rows and columns are intermittently provided in a direction perpendicular to the central axis of the catheter tube main body 63 on the circumference of the central portion thereof. Reference numerals 54 and 64 are distal end openings that communicate with the main lumens 55 and 65 of the catheter tube bodies 53 and 63.

The ribs 52 or the protrusions 62 are provided in the direction orthogonal to the central axes of the catheter tube bodies 53 and 63 for the following reason. That is, the balloons 51 and 61 of the balloon catheter are placed at predetermined positions in the blood vessel, and then back pressure due to the cardioplegic solution injected through the main lumens 55 and 65 (lumen for injecting cardioplegia solution) of the catheter tube bodies 53 and 63. The catheter may deviate from the indwelling position due to the weight of the catheter itself, etc.
This is because it is effective to provide the 52 or the protrusion 62 in a direction orthogonal to the central axis of the catheter tube main body 63.

[0005]

By the way, when a balloon catheter having ribs or the like on the outer surface of the balloon as described above is actually placed at a predetermined position in a blood vessel, it is surprisingly easy to slip out and is not very effective. That is, the balloon 51,
61, the ribs 52 or the protrusions 62 are provided in rows in the circumferential direction intermittently, so that it is not possible to increase the contact area between the ribs 52 or the protrusions 62 and the inner wall of the blood vessel, and the frictional resistance is increased. I wasn't able to fully demonstrate it. Also balloon 51,
With 61, a void portion is continuously formed in the circumferential direction between the rows of the ribs 52 or the protrusions 62, but this void portion hardly contacts the inner wall of the blood vessel and becomes a frictional resistance against slippage, and the balloon 51 , 61 could not be the resistance around the axial direction. From the above, in the balloon catheters of FIGS. 5 and 6, it is difficult to say that the contact frictional resistance force between the ribs 52 or the protrusions 62 on the outer surfaces of the balloons 51 and 61 and the inner wall of the blood vessel is sufficient. There is a problem that the balloon cannot be safely fixed and placed.

Therefore, the present invention solves the above-mentioned conventional problems and can increase the contact area between the ribs and the like on the outer surface of the balloon and the inner wall of the blood vessel, thereby increasing the contact frictional resistance. In addition, it is possible to effectively counter the force in the direction in which the balloon deviates, as well as the force around the balloon in the axial direction, and it is possible to secure a strong fixed indwelling so that the balloon does not easily slip out of the blood vessel. And a highly safe medical balloon catheter.

[0007]

In order to achieve the above object, the invention of claim 1 is such that in the medical balloon catheter as described above, the entire outer surface of the balloon is orthogonal to the central axis of the catheter tube body. The net-like ridges are provided. The invention according to claim 2 is the first part according to claim 1, wherein a plurality of reticulated ridges are arranged at a predetermined interval while being inclined at an acute angle with respect to the central axis of the catheter tube main body, and these. A plurality of second portions are arranged so as to intersect the first portion and are inclined at an obtuse angle toward the distal end side with respect to the central axis of the catheter tube main body and are arranged at predetermined intervals. According to the invention of claim 3, in claim 1 or 2, the medical balloon catheter is a balloon catheter for digestive tract.

[0008]

As described above, the ridges provided on the entire outer surface of the balloon are reticulated, and the reticulated ridges are not orthogonal to the central axis of the catheter tube body. The contact frictional resistance against the inner wall increases, making it difficult to slip out.

[0009]

1 is a front view of the balloon catheter with an open end showing an embodiment of the present invention with a part thereof omitted, and FIG. 2 is an enlarged side sectional view taken along the line AA of FIG. 1 in both figures
Is a catheter tube body made of silicone rubber or the like, and a balloon 2 is provided at the tip thereof.
The outer surface of the balloon 2 is entirely covered with the catheter tube body 1
The net-like ridges 3 are provided that are not orthogonal to the central axis of the. As shown in FIG. 3 in which a part of the balloon 2 before inflation is enlarged, the reticulated ridges 3 are inclined at an acute angle toward the distal end with respect to the central axis C of the catheter tube body 1 and are spaced at predetermined intervals. A plurality of first portions 3a arranged with a gap
And a plurality of second portions 3b which are inclined at an obtuse angle toward the distal end with respect to the central axis C of the catheter tube body 1 so as to intersect with the respective first portions 3a and are arranged at predetermined intervals. . That is, the inclination angles of the two portions 3a and 3b with respect to the central axis C of the catheter tube body 1 are symmetrically symmetrical with respect to the intersection, and due to the intersection, the force around the axial direction of the balloon 2 is increased. In addition to the resistance, it becomes possible to increase the contact frictional resistance with the inner wall of the blood vessel by making the lengths of both portions 3a and 3b based on the inclination angle in the circumferential direction of the balloon 2 longer. . The cross sections of these portions 3a and 3b are rectangular as shown in FIG. Both parts 3a,
One of the sizes of 3b is a balloon 2 as shown in FIG.
Has a width W of 0.1 mm to 3.0 mm, preferably 0.2 mm to 0.7 mm, and a height H of 0.1 mm to 2.0 mm, preferably 0.
It is desirable to set it to 2 mm to 0.5 mm. If the outer surface of the balloon 2 has a rough surface, the difference between convex and concave is 0.1 mm.
It is desirable to set the thickness to 2.0 mm, preferably 0.2 mm to 0.5 mm. In addition, it is convenient that the cross-sectional shape of both portions 3a and 3b is a rectangular cross-sectional shape having an edge as shown in the figure, because the contact frictional resistance with the inner wall of the blood vessel can be increased, but this is not always the case. The sectional shape is not limited to this.

In FIGS. 1 and 2, 5 is a main lumen of the catheter tube body 1, 6 is a tip opening communicating with the main lumen 5, 7 is a side hole, and 8 is a lumen for tip pressure measurement. It has an opening on the surface. Reference numeral 10 is a balloon inflation lumen, 11 is a funnel portion (hand portion), 12 is a tip pressure measurement connector, 13 is a cardioplegia solution injection connector, and 14 is a balloon inflation one-way valve.

Next, the operation of the embodiment will be described based on the following experimental examples. The balloon 2 of the 14 Fr balloon catheter of this example was placed on the bench in a carotid artery having an inner diameter of about 8 mm and fixed on one side, which was taken out from the corpse 1 to 2 hours after death and was inserted into the blood vessel for about 3 cm. Inject sterilized water from the one-way valve 14 for balloon inflation with a syringe of about 2 ml to reduce the balloon internal pressure to
The balloon 2 was inflated to 0 mmHg, and the catheter was fixedly placed in the blood vessel. Then, after attaching one of the round tension gauges (for 200 g) manufactured by Oba Keiki Co., Ltd. to the funnel portion 11 of this balloon catheter, gently hold the other of the tension gauges with fingers and pull the balloon 2
The maximum load on the verge of slipping out of the blood vessel was repeatedly measured three times under the same conditions, and the average value was calculated. On the other hand, the same test was performed using the conventional balloon catheters shown in FIGS. 5 and 6 having the same size as the balloon catheter of this example, and the maximum load of each was measured and the average value was calculated. The results were as shown in Table 1.

[0012]

[Table 1] As described above, it is clear that the balloon catheter of the present invention (FIG. 1) has less risk of slipping from the inner wall of the blood vessel and can be safely placed in the blood vessel. The reason for this is not clear, but according to the imagination, in the case of the balloon catheter of the present invention, the circumferential length of the balloon 2 formed by both portions 3a and 3b is the same as that of a conventional balloon catheter (see FIG. 5). , 6) are not orthogonal to each other as in the length of the corresponding portion, and are inclined to be longer as a whole, and the intersection of both portions 3a and 3b is against the axial force of the balloon 2. Is also a resistance. It is considered that this is because the contact frictional resistance is generally increased.

The balloon 2 having the net-like protrusions 3 on the outer surface thereof is, for example, a core pin having a net-like recess formed on its surface as a mold core pin (not shown) when the balloon 2 is press-molded. It is obtained by press-molding with a silicone rubber, removing the balloon from the press die, and inverting the inner surface and the outer surface of the balloon. In addition to the above-described molding method, the same thin net-like concave portion is formed on the surface of the balloon-molded portion of the press mold of the balloon, so that the balloon 2 having the mesh-like ridges 3 on the outer surface is similarly pressed. Obtainable. In this case, of course, it is not necessary to invert the balloon.

The balloon catheter shown in this embodiment is most suitable for use as a vascular catheter for protecting the heart myocardium, which is suitable for fixing a balloon placed in a blood vessel, but is of course limited to such an application. It can also be used for other fields of application. An example thereof is an ileus tube used for treatment of intestinal obstruction, which is a balloon catheter for the digestive tract. When the balloon of this ileus tube is a balloon having a net-like ridge similar to that of this embodiment on the outer surface, the reticular ridge on the outer surface of the balloon increases contact friction resistance with the intestinal tract, so that peristaltic motion or segmental motion of the intestinal tract causes There is a merit that the effect of promptly pushing to the target site of the intestinal tract is produced. In this way, by providing a mesh-shaped ridge on the outer surface of the balloon, a treatment that has never been seen before,
The merit in the inspection can be obtained.

[0015]

As described above, according to the invention of claim 1, since the mesh-shaped projections which are not orthogonal to the central axis of the catheter tube are provided on the entire outer surface of the balloon as described above, the contact between the balloon and the inner wall of the blood vessel is achieved. Friction resistance can be increased.
Therefore, it is possible to secure a firm fixation of the balloon that does not easily slip out of the blood vessel, and it is possible to perform surgery with peace of mind. The invention of claim 2 can be expected to have the same effect. Furthermore, the invention of claim 3 has an excellent effect that it can be applied to a balloon catheter for digestive tract.

[Brief description of drawings]

FIG. 1 is a partially omitted front view of an open-ended balloon catheter showing an embodiment of the present invention.

FIG. 2 is an enlarged side sectional view taken along the line AA of FIG.

FIG. 3 is a partial enlarged view showing a part of a balloon before inflation.

FIG. 4 is an enlarged partial sectional view taken along the line BB in FIG.

FIG. 5 shows a balloon catheter of a conventional example, (A) is a front view of a distal end portion thereof, and (B) is an enlarged partial sectional view of a balloon portion.

FIG. 6 shows another conventional balloon catheter, (A)
Is a front view of the tip portion thereof, and (B) is an enlarged partial sectional view of the balloon portion.

[Explanation of symbols]

 1 Catheter tube main body 2 Balloon 3 Reticulated ridge 3a part 3b part 5 Main lumen

Claims (3)

[Claims] 1. A medical balloon catheter having a balloon at the distal end of a catheter tube body, wherein a net-shaped ridge that is not orthogonal to the central axis of the catheter tube body is provided on the entire outer surface of the balloon. Medical balloon catheter. 2. A net-shaped ridge intersects with a plurality of first portions, which are arranged at a predetermined interval while being inclined at an acute angle toward the distal end side with respect to the central axis of the catheter tube main body, and intersect the first portions, respectively. 2. The medical balloon catheter according to claim 1, comprising a plurality of second portions which are inclined at an obtuse angle with respect to the central axis of the catheter tube main body and are arranged at predetermined intervals. 3. The medical balloon catheter according to claim 1, wherein the medical balloon catheter is a gastrointestinal balloon catheter.