NL9400027A - Brush catheter - Google Patents

Abstract

A brush catheter comprising an elongate, sleeve-like holder which can be introduced into the veins (blood vessels, arteries) of living beings. This sleeve contains a shank with hairs at the distal end. The brush part can be moved out of the sleeve in order to clean the walls of the veins. To prevent particles which have come free from blocking the blood supply during cleaning, it is proposed to provide collection means which, when the brush hairs are retracted into the sleeve in order for the brush catheter to be removed, provide a final collection feature for collecting such clots and other pieces. These collection means are preferably designed in the form of an umbrella.

Description

Brush catheter.

The present invention relates to a brush catheter comprising an elongated sleeve-shaped holder which can be inserted into the (arteries) veins of living creatures, with a brush arranged therein, comprising a stem extending beyond the proximal end and provided with operating means attached hairs located near the distal end of the sleeve, wherein the stem with hairs can be moved out of the sleeve near the distal end.

Such a catheter is known from German Offenlegungsschrift 3.92I.O7I. A catheter is known from this which has to be introduced into a vein through the skin. I.e. this catheter is inserted into the vein in question without surgery. In order for this to take place in a guaranteed manner, it is necessary to first insert a guide wire which serves as later guidance for the brush catheter. As a result, the handle on which the brush is applied is made hollow. During the cleaning operation, the vein or artery is perfused. This presents particular problems with regard to the blood clots released during the cleaning operation. At all times it must be ensured that such blood clots cannot release. In addition, the opening made in the vein (artery) is relatively small due to this construction. Therefore, it is imperative that the affected blood clots be contained in the sleeve into which the brush can be slid. Due to the fact that the brush handle is hollow, and because it must be possible to accommodate the clots in the sleeve surrounding the brush, it has a relatively large diameter, which considerably limits the applicability with relatively small diameter cores.

The object of the present invention is to provide a brush catheter, which can be used in surgical procedures, ie in procedures involving the release of the respective vein or artery, the cessation of blood circulation through the affected vein and the introduction of the catheter as well as possible can clean veins with a very small size.

This object is accomplished in a brush catheter described above in that the stem is solid and that in the expanded state, the circumference of the bristles formed by the bristles is at least 50% greater than the circumference of the sleeve-shaped container near the distal end. With the device according to the invention it is not necessary to receive the clot within the catheter. Since the brush handle can now be made solid and the clot no longer needs to be received in the catheter, the catheter can be made relatively thin and in this way be introduced into relatively very thin veins. A diameter of the cores of 2 mm can be mentioned as an example. When the brushes are located outside the catheter and loosen deposits from the wall of the vessel and these deposits are moved back, these deposits may be located in the space at the front of the catheter between this catheter and the vessel. After all, the catheter has a diameter that is very much smaller than the diameter of the vessel.

It is to be noted that U.S. Pat. No. 3,996,938 discloses a catheter in which a foam material portion is used in place of a brush which, in contrast to the present invention, cannot be slid in and out of a sheath but is positioned at the front of a sleeve. By operating the stem, the foam material can be formed into a sphere and in this way a treatment comparable to a dope treatment can be carried out. In addition, the part of the stem lying in front of the foam material is provided with a rounded cone to enable guidance in the vessels.

"Proximal end" is here understood to mean the end closest to the operator, while the "distal end" is that end where the actual treatment takes place.

According to an advantageous embodiment of the invention, collecting means are present at the distal end of the stem. These serve as additional security to remove any brush deposits that have come loose from the vessel wall.

According to an advantageous embodiment of the invention, the collecting means are designed to be foldable in the direction from the proximal end to the distal end. This means that they can move along any obstacles during insertion, but act upon them during retraction. Moreover, it is therefore possible that the collection means are arranged over the distal end of the sheath during the insertion of the catheter.

According to a further advantageous embodiment, the collecting means are of an umbrella-shaped design and are formed with a boiling point away from the distal end. For example, smooth guidance is provided when the catheter is inserted into the (arterial) vein system of the patient.

Depending on the application, the bristles of the brush can be made of hard or soft material. When used in by-pass (articulated) core parts using plastic, it is desirable to use a slightly hard brush to remove neo-intima deposits. It is desirable to use soft hairs in natural veins.

In order to optimize the removal of clots and other cleaning parts, it is preferred that a collection space is delimited between the collecting means and the nearest hairs of the brush.

The invention will be explained in more detail below with reference to an illustrative embodiment shown in the drawing. Show:

Fig. 1 the brush catheter according to the invention in side view and partly in cross-section in the state after insertion into a vein system and during cleaning;

Fig. 2 the catheter of FIG. 1 in the closed position upon insertion into the vein system; and

Fig. 3 the brush catheter according to the invention is introduced into the vein system (bypass) of a patient.

The brush catheter of the invention is for treating thromboembolic abnormalities. This can be done by surgical intervention. An example is the Fogarty balloon catheter to remove deposits. This balloon catheter cannot effectively remove such deposits or neo-intima. In addition, the balloon of this catheter must be inflated and therefore has a varying diameter while the danger of balloon rupture or perforation of the blood vessel may cause irresponsible complications.

To this end, the brush catheter according to the invention is proposed, which is indicated in its entirety by 1. This consists of a sleeve 2 at the proximal end 6 provided with handles 10. This sleeve 2 consists of a relatively flexible material, so that it can be moved through the veins of the patient. The catheter has a relatively large length, so that it is possible to bridge a distance of tens of centimeters with it. A stem 4 is arranged inside sleeve 2. At the proximal end there is a handle 8 for operating it, while the distal end thereof is provided with bristles 3 · The end is provided with an umbrella 7 · In the position shown in fig. 1, the bristles 3 are moved outwards and a collecting space 9 is available between umbrella 7 and these bristles.

Fig. 1 shows that when the bristles are folded out, the circumference thereof is at least 50% larger than the circumference of the sleeve 2. As a result, clot can be received in the space near the free end of the sleeve 2 lying between the outer circumference of this sleeve 2 and a vein. The brush also has a fixed diameter so that the barrel is not damaged.

In Fig. 3 the insertion of the brush catheter according to the invention into a vein system 11 with closure is shown. A bypass 12 is provided in this vein system 11, which consists of a plastic material which has grown together with the vein system. In order to remove deposits from this plastic part, which lead to silting up of the bypass, so-called "neo-intima", the brush catheter with at least the bristles 3 located inside sleeve 2 is introduced through the vein system 11 to the location of the constipation. This position can be recognized in all ways known in the art. Then the brush part is moved outwards by operating geep 8; this can be done repeatedly by moving back and forth. Since deposits with such a bypass are relatively difficult to remove, hard bristles will be used for the brush. However, if brush 3 is used in completely natural veins, softer bristles will be used. Parts of the wall of the bypass 12 will become loose as a result of the cleaning movement. Material located in front of the front bristles that is not affected by it will be contained within space 9 · This will trap the last clots and ensure they are prevented from entering the patient's bloodstream. By using such a brush, damage to the vessel during cleaning will be prevented. On the other hand, the removal of unwanted deposits will be complete. The length of such deposits, as well as the location, is of minor importance. When using soft brushes, the intimal layer or arteriosclerosis parts will not be affected. This is particularly important because in all-natural veins they are less strong than veins that have not been deposited. By using this method, it is no longer necessary, as with doping, to follow the catheter site using X-rays. After all, it has a constant diameter and the cleaning effect will be the same everywhere.

As an example for the dimensions of a brush catheter according to the invention to be used for cleaning veins with a diameter of 2 mm, the following values may apply. The catheter has an external diameter between 1 and 1.5 mm, while the internal diameter is between 0.75 and 1 mm. When folded out, the bristles have a diameter of 3 and 4 mm.

Although the invention has been described above with reference to a preferred embodiment, it is to be understood that numerous modifications can be made thereto without going beyond the scope of the present application. For example, the umbrella can be designed in any other manner known in the art, in which it is only important that, on the one hand, good conductivity is ensured during the insertion of the catheter into the vein system and, on the other hand, that sufficient collection space is created to allow released deposits. at the edge of the sleeve. All such variants are considered to be within the scope of the appended claims.

Claims (7)

Brush catheter (1) comprising an elongated sleeve-shaped holder (2), which can be inserted into the veins of living creatures, with a brush arranged therein, comprising a shaft (4) extending outside the proximal end operating means (8) and hairs (3) located near the distal end (5) of the sleeve, the stem with hairs being movable out of the sleeve near the distal end (5), characterized in that the stem (4) is solid and that in the expanded state, the circumference of the bristles formed by the bristles is at least 30% larger than the circumference of the sleeve-shaped container near the distal end. A brush catheter according to claim 1, wherein at the distal end the stem is provided with rigid receptacles at least in the direction from the distal to the proximal end. Brush catheter according to claim 2, wherein said collecting means are collapsible in the direction from the proximal to the distal end. Brush catheter according to any one of the preceding claims, wherein said collection means (7) are formed in an umbrella shape with the boiling point away from the distal end. Brush catheter according to claim 4, wherein the largest peripheral edge of the receiving means in the folded-out state has a larger internal diameter than the outer diameter of the sleeve near the distal end. Brush catheter according to any of the preceding claims, wherein the bristles consist of a relatively hard material. Brush catheter according to one of the preceding claims, that a collecting space (9) is present between the collecting means and the nearest hairs of the brush in an brought-out condition.