DK168940B1 - Dilatation balloon catheter - Google Patents

Abstract

The dilatation balloon catheter (10) has a catheter line (11) on which there is arranged in an axially immovable manner a flexible balloon (12) which can be expanded by pressure fluid. The balloon (12) has a braid tube (15) provided with at least one fluid-tight elastic covering (16, 17). The braid tube (15) is woven from two warps (21, 22) of elastomeric threads running in opposite directions. Woven into this braiding are strands (23, 23') of high-modulus fibres extending in the axial direction of the braid tube in such a way that the single strand (23; 23') runs over the threads of the one warp and under the threads of the other warp. The length of the expandable area of the balloon (12) amounts to at least 4 times the maximum outer diameter of this balloon area in the unexpanded state. <IMAGE>

Description

DK 168940 B1 i

The invention relates to a dilatation balloon catheter, hereinafter briefly referred to as a balloon catheter, according to the preamble of claim 1.

The following definitions are used below: 5 "Medium tight" is understood to mean the impermeability of gases, vapors and liquids. By a medium is meant a gaseous, vapor or liquid. By a monofilament, often also referred to as monofilament yarn, monofilament yarn, monophile or endless fiber, is meant a thread consisting of a single filament, no matter how large its cross-section. A multifilament, also known as multifilament yarn or multifilament yarn, is to be understood as a thread consisting of a plurality of filaments. Preferably, the filaments may be endless chemical or synthetic fibers. By braid hose is meant a braided stocking 15 or hose.

Balloon catheters to which the present invention relates may be so designed that the catheter conduit is terminated at one end by a medium tight. The invention also relates to a balloon catheter, wherein the catheter conduit has at least one groove 20 extending the full length of the catheter conduit and open at both axial ends. In general, the invention relates to balloon catheters which can be introduced from the outside into the bodies of living beings, especially humans, through natural or artificially created openings. In the introduced state, the balloon, by means of a pressure medium introduced therein, which may preferably be a gaseous or a liquid, can be expanded to be retained in the particular body opening, such as a ureter, other conduit or duct, vessel, wound or the like. and / or in this body opening or similar means to form a closure or to expand the body opening or similar organ.

Balloon catheters according to the invention may have various medical uses, for example for nephrosomy, for introduction into blood vessels, ureters, surgical wounds or serve other desired medical purposes.

35 In a known balloon catheter of this type as described in DE-Al 33 37 258, the catheter shaft has a tube of braided material which is enclosed in a larger area of its length in an inelastic sheath of semi-rigid material which extending from the proximal end of the catheter over a larger portion of the shaft length. An outer sheath of elastic material extends over a smaller portion of the length of the shaft at or in the region of the distal end of the catheter, whereby this smaller portion of the shaft is inflatable or expandable as a balloon. This does not allow the balloon to expand beyond certain permissible limits.

Also, dilatation balloon catheters are known, 10 having the same two grooves construction as described above, but here, however, there is an outer sheath of inelastic, cross-linked polyethylene (PE) irradiated. Here, medium is pressed into the balloon until the PE sheath, which had previously been folded around the catheter in unfilled condition, has unfolded to its maximum contour. During this unfolding, the internal pressure is only increased to a negligible degree, and only at the end of the unfolding process, and when the maximum size of the balloon is reached, the pressure clearly increases. The final contour is limited by dimensioning 20 of the complete PE balloon cuff. There are also dilatation catheters in which the outer sheath consists of elastic strands with elastic coating.

Initially, the inflating process of this type of catheter proceeds as an increase in pressure, and at the end, when the maximum contour is reached, the pressure has also reached its maximum. Further increase of pressure leads to bursting of the balloon. The contour restriction is obtained by the elastic limit of the strands interlaced in the wall of the balloon.

However, because of the braid characteristic, this balloon bends into undesirable forms, for example in banana form, when the maximum inflation pressure is reached. The handling, e.g. the displacement of the tube, as required by nephrostomy balloon catheters, over the balloon is greatly hampered or hindered by the "wrong" shape.

The object of the invention is to provide a balloon catheter, the balloon of which cannot be expanded arbitrarily, but which, in addition, can also be supplied internally with pressure medium under a particularly high pressure (dilatation pressure), so that in the enlargement of it in a body opening, a blood vessel, a ureter, a urethra, etc. inserted balloon into the balloon catheter at the high dilatation pressure of the balloon to be able to squeeze any local resistance-producing tendons, fascia, and other resilient tissue material. The invention should at the same time enable the balloon to be elongated and yet achieve that the balloon also retains a hose-like shape, preferably with practically constant outer cross-section in its expanded area.

This is achieved in accordance with the invention by a balloon catheter of the kind set forth at the outset and which is characterized by the characterizing part of claim 1.

The balloon in the balloon catheter according to the invention, due to the strands of high elastic modulus fibers, despite the elastomeric threads in both thread groups, even at high pressures, does not expand strongly, but even at great length of the balloon it has been found that the outer diameter of the expanded balloon area is substantially constant over its entire length and thus in a rectilinear position has an approximately round, cylindrical shape. It has even succeeded in providing the expanded balloon, with the exception of its axial ends, a practically rigid cylindrical, especially round, cylindrical shape, so that it has the same circular cross-section here throughout.

25 High elastic modulus fibers are known and therefore need no further explanation. They are distinguished by low elongation at a maximum of a few percent as well as by high strength. For example, high elastic modulus fibers may conveniently consist of high molecular weight polyethylene and / or para-amide and / or carbon and / or other suitable high strength materials. Fibers with large elastic modulus of para-aramid are e.g. known by the trade name "Kevlar". Furthermore, the elastomeric threads in the two interlaced string groups are often referred to as braid threads. They consist of more elastomeric fibers. These braids may preferably be monofilaments or multifilaments or, if desired, made of spun fibers. These braids may, for example, consist of DK 168940 B1 4 resin, preferably segmented polyurethane, or of rubber, rubber, latex or other suitable elastomeric materials. For example, their fiber may be those marketed under the trade name "Lycra" and manufactured by Du Pont.

5 The strands of the strings are not referred to as braids, but, when appropriate, to distinguish them from the braids as strands. Also, the strand wires may preferably be monofilaments or multifilaments. However, it is also possible that the strand yarns are made of spun 10 fibers when, in this case too, sufficient strength is obtained by low elongation at break.

The break elongation for the strands in the strand threads may preferably be a maximum of 10%, preferably a maximum of 6%, and particularly advantageously, break extensions of at least 1%, preferably at least 2% and / or a maximum of 5%. The strings then prevent even too much expansion of the balloon when the pressure medium serving the expansion is inadvertently initiated into the balloon under an excessively high pressure, whereby any operating errors have no negative effects.

The strands also safely prevent an excessive elongation of the elastomeric braids so that, even after long use, they retain their elasticity and so that after long use of the balloon catheter, after use, each time again assumes its original shape , and thus, this balloon catheter in use does not undergo an inconvenient enlargement of the enlarged balloon.

The invention also provides the important advantage that the balloon with the pressure medium can be expanded by means of high pressure, for example with pressure of several to many bars, for example with 30 pressures of 2 to 20 bar, so that the balloon can, for example, push cartilage, fascia , tendons, muscle layers and other resistant tissue material as a result of the high balloon pressure, which allows for a straight, better balloon catheter storage in the blood vessel, channel 35 or similar opening in the living creature and also enables a particularly good seal along the balloon. circumference.

The length of the balloon may vary according to the desired application purpose, for example suitably 10-400 mm and particularly conveniently approx. 40-300 mm.

In addition, the wall thickness of the balloon may be relatively small, for example 0.5-1.2 mm, or as the case may be 5 thinner or thicker. The catheter cord, i.e. the catheter tube or rigid catheter tube may also have small outer cross-sections of, for example, 0.8-3 mm or, depending on the conditions of use, be thinner or thicker. The catheter conduit may preferably have an approximately constant contour throughout its length, preferably a circular outer contour.

Particularly appropriate include for easy insertion of the balloon catheter into body openings and similar openings, it is when the balloon abuts close to the catheter conduit in emptying, i.e. in the non-enlarged state and without folding, which is particularly convenient at the length of the catheter conduit enclosed by this balloon.

The balloon must be medium-tight of the outer socket. For this, the braid hose on its outside and / or inside may have a medium-tight expandable hose-shaped sheath. In many cases, such a sheath may be provided, either internally or externally only on the braid hose. Preferably, a sheath may be provided both on the inside and the outside of the braid hose. The sheath may, for example, consist of elastomeric material, for example of plastic, rubber or the like. Preferably, when two sheaths are provided, these two sheaths may be inextricably linked to each other through breakthroughs or welding locations which pass through the braid hose.

The inner sheath and / or outer sheath of the braid hose may preferably be adhered thereto. The adhesive may be adhesive by application of additional adhesive or cohesively by etching or solvent adhesive of the respective jacket (s).

The elastic extension of the cap or sheaths may preferably be so large that the limit of elasticity during use 35 is not exceeded.

The extensible area length of the balloon is at least 4 times that of the balloon which is in the expanded state, outer cross sections are advised, in spite of the small fracture extension for the strands, to obtain sufficient extensibility of the balloon. Preferably, this length of the expandable area of the balloon may be at least 10-fold, preferably at least 15-5-fold of the maximum outer cross-section of this balloon region in the extended state.

It may conveniently be provided that the braid hose is designed so that the balloon's inertial cross-section illumination when expanded with the aid of pressure medium so that the strands have obtained approx. 90% of their elongation at break, in the extended region, is at most 5 times, preferably at most 2 times, especially often preferably at most 1.5 times the illuminating cross section of the non-expanded balloon.

Preferably, the braid hose may be so designed that adjacent strands are arranged such that one strand runs over the threads of the first thread group seen from the outside and below the threads of the second thread group, whereas at the second strand the threads of the first thread group run below and the threads of the 20 the other thread groups run over. Also, other locations of the strings can often come in handy. Thus, it can often be conveniently arranged for the strands of the braid hose to be arranged such that at each other group of n adjacent strands, the threads of the first thread group are viewed from the outside and the threads of the second thread group below, and that at lying string groups, each consisting of m strings, crosses the threads of the first thread group and the threads of the second thread group, whereby n and m are whole numbers greater than 1. Preferably n and m for both string groups are equal or equal to 2 or 3.

Furthermore, it can conveniently be ensured that at least one strand, preferably all strings, consists of each one strand. However, it is also possible and also often convenient to ensure that at least one strand, preferably all strings, consists of each a bundle of several strands. These strands in the strand may conveniently be so-called smooth strands, which are thus not textured. The braid threads in both thread groups can also conveniently be smooth, ie not textured threads.

Conveniently, each thread in one thread group may be arranged so that from the outside it has its intersecting 5 threads from the other thread group alternately running above and below.

The number of strands in the braid hose may preferably correspond to the maximum number of braid coils from which the braiding threads in both thread groups emerge by braiding the braiding tube. Preferably, the number of strands may equal half of this braid coil number or be greater or smaller.

The balloon attachment to the catheter conduit may be in any suitable manner, preferably according to the measures of claim 14 or 15.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will now be further elucidated in connection with some embodiments and with reference to the drawings, in which: 1 is a sectional side elevational view of a section of a balloon catheter according to an embodiment of the invention; FIG. 2 is an enlarged longitudinal section through a portion of the balloon catheter of FIG. 1, FIG. 3 is a section through the balloon catheter of FIG. 2 taken along section line 3-3, FIG. Fig. 4 is a braid hose for explaining its structure seen in the direction of its longitudinal axis, the other parts of the balloon catheter in this embodiment being indicated by dash dot; 5 is a top plan view of a folding of the braid hose according to FIG. 4 to show its structure; and FIG. 6 shows an asymmetric variant of the braid hose of FIG.

30 4, also seen in its axial direction.

The balloon catheter 10 of FIG. 1 and 2 have a catheter conduit 11 and an expandable balloon 12 disposed on its left end region, which exhibits no folds. The catheter conduit 11 is formed as a thinner, at the left end closed flexible hose with a constant circular cross-sectional profile and here consists of plastic, for example polyurethane, but may also consist of other suitable flexible or rigid materials which do not may be inappropriately expanded by the extension of the balloon 12, in the aperture 13 of this hose, ie. introduced into the exemplary embodiment in its only through-going pressure medium, e.g.

5 air or liquid. This pressure medium, due to the design of the balloon 12 described below, can have very high dilatation pressure, i.e. pressure to expand the balloon, for example 6-20 bar. Furthermore, the balloon has the property that, at relatively low pressure (dilatation pressure) in the pressure medium, it expands almost maximally and at further pressure rise it does not expand further, but at the higher pressures it can displace muscles, tendons and other inappropriate tissue parts. or similar means which form local resistance to its expansion, so that, by the application of high pressures, it is possible to achieve this displacement.

As shown, when the catheter conduit is closed at one end, it is sufficient when it has a single recess 13, as is the case in the exemplary embodiment, and 20 in the recess then the pressure medium for expanding the balloon 12 is introduced, to which in the wall of the recess 13 holes 14 are disposed within the expandable area of the balloon 12.

The balloon 12 also lies in its non-expanded state, with its expandable area close to the catheter conduit and preferably to the total length of the catheter conduit, enclosed therewith.

The balloon 12 comprises a braid hose 15 which is outer and inner coated with a medium-tight, elastically expandable sheath 16, 17, preferably with elastomeric sheaths 16, 17, 30 interconnected or welded together with bridges penetrating the breakthroughs of the braid hose 15. The state of the balloon extended by means of the balloon 12 introduced into the balloon 12 via its aperture 14 and the holes 14 is shown to be dotted, and it is seen that the region of the balloon 12 expanded or spaced out has a substantially cylindrical tubular shape. Upon pressure relief of the pressure medium, the balloon 12 returns completely again, even after prolonged use, to its original, fully drawn form, in which it again abuts the catheter conduit 11 without folds and in its full length. Also in the expanded state, the balloon 12 has no folds.

A possible and advantageous construction of the braid hose 5 15 is now explained in more detail in connection with one in FIG. 4 and 5, in which FIG. 4 as opposed to FIG. 1-3 have two apertures 13 ', 13 ", of which aperture 13' is the main aperture which does not communicate with the balloon 12 so that it can be open at both ends 10 of the catheter conduit 11, whereas aperture 13" is at one end of the catheter cord 11. This aperture 13 "communicates via at least one hole 14 in medium conductive communication with the interior of the balloon 12.

The FIG. 4 and 5, diagrammatically shown, braided hose 15 is braided by two opposing thread groups 21, 22 each with eight braids 27 and 27 ', respectively, using each eight braiding coils while interleaving eight in the axial direction of the braided hose 15. high elastic modulus fibers, for example conveniently of polyethylene or carbon consisting of strands 23, 23 '. The elastomeric braided threads in the thread group 21 are designated 27 and those in the thread group 22 are designated 27 ', however, only some of these braided threads 27, 27' are shown in section.

In this embodiment, each strand 23 and 23 ', respectively, consists of only one monofilament or multi filament, preferably a smooth monofilament or one of smooth filaments consisting of smooth filaments. In this embodiment, this braided hose has a total of eight strands 23, 23 '. Thus, it is particularly convenient when the braiding yarns 27, 27 '30 are formed by braiding each of eight braids, i.e. when from each braid coil a single braided thread 27 or 27 'assumes that each thread group 21, 22 consists of every eight braided threads, although, for example, the number of strands 23, 23' may also be greater or smaller, preferably corresponding to the maximum number of 35 braiding coils from which the braiding yarns 27, 27 'emerge by braiding the braided hose. If desired, it may also be larger or smaller, for example, corresponding to a quarter of the braid bobbin number. Conveniently, the number of braid coil may be larger, the greater the maximum outer diameter of the inflated balloon and its dilatation pressure.

In this particularly advantageous embodiment, the strands 23, 23 'go between the braided wires 27, 27' as shown, so that, as seen in the circumferential direction of the braided hose, the next strand 23 extends below the braided wires 27 in the thread group 21 and goes above of the thread group 22. The strands 23 in between there? goes under the braided strands 27 '10 of the thread group 22 and runs over the braided strands 27 of the thread group 21. According to FIG. 5, the strings 23, 23 'are seen in the parallel longitudinal axis of the braided hose 15, distributed at equal center angles about the circumference of the braided hose 15, but they can, e.g. FIG. 6 be positioned 15 at unequally centered angular distances apart.

Each string 23, 23 'thus extends in the axial direction of the braided hose. The strings 23, 23 'are parallel to each other and do not extend helically or helically around the tubing, but each strand extends at a rectilinear balloon to the longitudinal center plane of the 20 braided tubing.

A numerical embodiment of braid hose 15 is also given:

The wall thickness of the balloon is approx. 0.9 mm. The outer diameter of the catheter cord 11 is approx. 2.3 mm. The maximum outer diameter 25 meters D of the expandable balloon's expandable area is approx. 4.1 mm. The total length of the balloon 12 hg is approx. 200 mm. Length La of the expandable area of the balloon 12 is approx. 170 mm. The braided yarns 27, 27 'are multifilament yarns which consist of filaments of rubber, such as lycra (leather). The fineness of the individual braided 30 strands 27, 27 'is approx. 406 dtex. Their tensile elastic modulus E100 is 0.046 N / mm2. Each strand 23 and 23 'is a multifilament of para-aramid with a fineness of 380 denier. The lines 23, 23 ', like the braided wires 27, 27', are adhered to the sheaths 16, 17 and adhered or welded together with 35 by bridges extending through breakthroughs in the braided hose 15.

The balloon 12 forms, before it is pushed onto the catheter joint 11 and is removably attached thereto, in a straight line, a cylindrical tube.

The braided hose is shown in FIG. 1 and 2 attached to the catheter conduit in that the 5 of each of two short axial longitudinal end regions is wound tightly with a thread (wound thread). These winding threads extend beyond the two length units of the braided hose 15 and the inner sheath 17 of the catheter line 11. Only then is the outer sheath 16 placed. For example, it may be arranged by immersing the area of the balloon catheter 10 provided with the balloon 12 in a bath of a polymer solution so that the outer sheath 16 thus acts as an outer coating or tube on the balloon 12 and, if applicable, also on the braided tube. 15 and the tubular inner sheath 17 15 and also completely wraps the winding threads 24 so that they can no longer be released. In this manufacture, the outer sheath 16 is adhered or welded by itself to the inner sheath 17 and also adhered to the braided hose 15 when its wires 27, 27 ', 23, 23' consist of material which can be adhered to the outer hose 20, which is particularly convenient. . After removal of the catheter tube with the balloon from the said polymer solution, the outer sheath 16. dries the areas of the catheter conduit 11, which should not carry any outer sheath, as far as possible are not immersed in the polymer solution, or one can subsequently coat the outer sheath in the respective areas of the catheter conduit 11 with a protective layer before immersion in the bath, for example with wax, which allows easy removal of the outer sheath in these areas.

The balloon catheter may serve various purposes, such as 30 duct duct dilator, nephrostomy dilator, ureter dilator, urethra dilator, cardiac stenosis dilator, and further have additional applications.

When expanding the balloon 12 of the balloon catheter 10 by supply of pressure medium, the following excellent property. By extension, the expandable balloon area retains a substantially circular cylindrical shape and at a certain, still relatively low pressure of the printing medium is balloon 12 DK 168940 B1

The maximum outer cross-section of the ion is practically obtained and upon further increasing the pressure of the pressure medium, this maximum outer cross-section changes practically no more. The pressure 4 may then increase so much that it is in the vicinity of the burst pressure, 5 at which also the braid hose would burst upon destruction s of at least one strand. For example, when the burst pressure is 24 bar, the pressure medium can be pressurized to a maximum of, for example, a maximum of 12 bar and then have a fully adequate safety limit before the burst pressure is reached.

The balloon catheter is characterized in that, after each expansion, the balloon 12, when the pressure of the pressure medium is again lowered, returns to its original shape, in which it again rests close to the outer wall of the catheter conduit. This also provides lasting insertion properties for the balloon catheter in socket canals, branching ducts, body openings, surgical wounds, etc., even after many times of use.

Claims (18)

A dilatation balloon catheter having an elongated, hollow catheter conduit on which is axially and displaceably disposed 5, an expandable, flexible balloon with a pressure medium, which pressure medium may be introduced through at least one lumen of the catheter conduit and into the space between the balloon and the catheter conduit and again. can be directed therefrom, which balloon has a braid hose provided with at least one medium-tight elastic sheath, characterized in that the braid hose is braided by two opposing thread groups (21, 22) of elastomeric threads, and in this interlacing under the braid is interwoven in the axial direction of the braid hose (15) extending strands (23, 23 ') of fibers with a large elasticity 15, so that the individual strand extends from the outside over the threads of one thread group (21) and under the threads of the second thread group (22), and that the length of the expandable area of the balloon (12) is at least 4 times the maximum outer cross section of this balloon. as condition. 20 Dilatation balloon catheter according to claim 1, characterized in that adjacent strands (23, 23 ') of the braid tube are arranged so that one strand (23) extends from the outside over the strands of the first thread group (21) and under the threads of the second thread group (22), whereas the second strand (23 ') runs under the threads of the first thread group (21) and over the threads of the second thread group (22). A dilatation balloon catheter according to claim 1, characterized in that the strands of the braid tube are arranged such that each other group consisting of n adjacent strands as seen from the outside extends over the strands of the first thread group and below the threads of the second thread group, and that the intermediate strand groups, each of which consists of m strands, runs under the threads of the first strand group and over the threads of the second strand group, where n as well as m are an integer greater than 1 and preferably 2 or 3 or preferably equal. 14 DK 168940 B1 Dilatation balloon catheter according to one or more of the preceding claims, characterized in that at least one strand, preferably all strands, each consists of a strand or a strand of multi-strand filaments and the strands (23, 23 ') preferably mutually having the same metric number. Dilatation balloon catheter according to one or more of the preceding claims, characterized in that the elastic elasticity of the wires (27 27 ') in the wire groups (21, 22) is at least 20%, preferably at least 50% or at least 100%. and / or a maximum of 800%, preferably a maximum of 500%. Dilatation balloon catheter according to one or more of the preceding 15, characterized in that the breaking elongation of the strands (23, 23 ') is at least 1%, preferably at least 2% and / or maximum 10%, preferably maximum 6% or maximum. 5%. Dilatation balloon catheter according to one or more of the preceding claims, characterized in that the catheter conduit (11) is a flexible tube. Dilatation balloon catheter according to one or more of the preceding claims 1-7, characterized in that the braid tube (15) has breakthroughs, that the braid tube (15) is preferably provided both on the outside and the inside with a medium-tight sheath (16, 17). ), which sheaths are preferably in place bonded or welded to each other via at least some of said breakthroughs in the braid hose (15), and that the outer sheath (16) preferably extends beyond at least one axial end of the braid hose. Dilatation balloon catheter according to one or more of the preceding claims, characterized in that the braid hose (15) is held to the catheter conduit by at least one of its longitudinal end regions by wrapping with at least one wire (24) (hereinafter referred to as winding wire). (11) and is extensible in the wound region (s) in which preferably this braid hose including at least one of its length regions wound by at least one wound thread is provided with an outer, elastic, medium-tight sheath (16). Dilatation balloon catheter according to one or more of the preceding claims, characterized in that each of the two axial end regions of the braid tube is held by a thermoplastic, heat-shrinkable shrink tube to the catheter line, wherein the shrink tube is adhered or welded together with both the catheter line and with braid hose. Dilatation balloon catheter according to one or more of the preceding claims, characterized in that the catheter conduit (11) is terminated at one end at medium density and preferably has a single longitudinal channel or groove (13). Dilatation balloon catheter according to one or more of claims 1-9, characterized in that the catheter conduit 20 has a main illumination (13 ') and at least one additional illumination (13 "), whereby only the at least one additional illumination serves to supplying the pressure medium serving to expand the balloon. Dilatation balloon catheter according to one or more of the preceding claims, characterized in that the braid hose (15) is designed such that the free inner cross-section of the balloon (12), when so expanded by pressure medium, that the strands (23, 23 ') ) is affected to approx. 90% of their fracture elongation, in the extended region, is at most 5 times, preferably at most twice, or preferably at most 1.5 times the free inert cross section of the non-expanded balloon. Dilatation balloon catheter according to one or more of the preceding claims, characterized in that the strands (23, 23 ') of the strands consist of high molecular weight polyethylene and / or para-aramid and / or carbon. DK 168940 B1 16 Dilatation balloon catheter according to one or more of the preceding claims, characterized in that the strands (23, 23 ') of the strands consist of monofilaments and / or multi-filaments. 5 Dilatation balloon catheter according to one or more of the preceding claims, characterized in that the length of the expandable area of the balloon (12) is at least the 5-fold, preferably at least the 15-fold of the maximum outer cross-section of this balloon area 10. Dilatation balloon catheter according to one or more of the preceding claims, characterized in that the number of strands (23, 23 ') in the braid hose (15) corresponds to a maximum of 15 the number of braiding coils, preferably half the number of braiding coils from which both thread groups (21, 22) appeared when braiding the braid hose (15). Dilatation balloon catheter according to one or more of the preceding claims, characterized in that the balloon in the non-enlarged state, in which the expandable area preferably adjoins the catheter conduit, is free of longitudinal folds and preferably is completely free of folder. 25