CN116801935A

CN116801935A - Catheter system with hydraulic expansion stabilizer

Info

Publication number: CN116801935A
Application number: CN202280012431.2A
Authority: CN
Inventors: M·贾诺蒂; D·玛盖塔; J·库里克; M·吉特; U·弗里茨
Original assignee: Biotronik AG
Current assignee: Biotronik AG
Priority date: 2021-02-01
Filing date: 2022-01-28
Publication date: 2023-09-22

Abstract

This document relates to an improved PTA conduit, an improved PTA plant and an improved PTA process, which solve the problems associated with the PTA process. Embodiments of the improved PTA catheter include a PTA catheter having one or more stabilizers activated to hold or fix the PTA catheter in a desired relative position within the support catheter. The improved PTA method employs timely activation of a stabilizer to prevent deformation of the PTA device during endovascular operation. Some embodiments include hydraulically activated stabilizers, while other embodiments employ one or more stabilizers activated by an activation method other than hydraulic activation.

Description

Catheter system with hydraulic expansion stabilizer

Technical Field

The present invention relates to a catheter system comprising or consisting of: a first catheter having a first lumen surrounded by a first catheter shaft; and a second catheter inserted into the first lumen of the first catheter, and having a second lumen surrounded by the second catheter shaft, and one or more hydraulic expansion stabilizers in fluid communication with the second lumen. The one or more stabilizers are adapted to form a radially outwardly expandable inflation fluid chamber upon hydraulic expansion through the second lumen, thereby pressing the stabilizers against the inner surface of the first catheter shaft and fixing the position of the second catheter within the first catheter and constraining the second catheter to a coaxial arrangement relative to the first catheter.

The present application also relates to an improved percutaneous transluminal angioplasty device for treating occluded arteries, veins and other blood vessels in biological tissue, the device comprising a stabilizer activated to fix the relative positions of components of the percutaneous transluminal angioplasty device which translate relative to each other during certain portions of the percutaneous transluminal angioplasty procedure to prevent relative movement of the components during other portions of the percutaneous transluminal angioplasty procedure.

Background

Percutaneous transluminal angioplasty ("PTA") refers to a method of dilating a stenosed vessel using a balloon catheter. Typically, the blood vessel is narrowed by the presence of atherosclerotic plaque formed in the vessel wall. Atherosclerotic plaques contain lipids, inflammatory cells, smooth muscle cells, and connective tissue cells, and are typically formed in areas of the vessel wall exposed to non-laminar or turbulent blood flow, including areas of the vessel wall near arterial branch points. Plaques often begin with early atherosclerotic lesions, known as "fatty streaks," containing macrophage-induced lipid-filled foam cells formed by uptake of enzymatically oxidized lipids from circulating low-density lipoproteins and very low-density lipoproteins, including oxidized sterols and 4-hydroxynonenal. Macrophages secrete pro-inflammatory cytokines that recruit smooth muscle cells to the lesion and stimulate the growth of additional macrophages, resulting in the growth and progression of early atherosclerotic lesions into subendothelial fibrous plaques with fibrous caps that may in turn be calcified. Atherosclerotic lesions are complex substrates of various types of cells, cell residues, lipids, oxidized lipids, inorganic ions, and even invasive bacteria. Atherosclerotic lesions result in limited blood flow, cause ischemic disease, manifest as insufficient blood perfusion of blood vessels, limbs and vital organs, are often accompanied by the formation of blood clots and further lesion growth, also known as "stenosis", and may lead to acute life threatening diseases such as myocardial infarction or chronic limb ischemia. In percutaneous transluminal angioplasty ("PTA") procedures, a pre-folded and collapsed balloon catheter, known as a "PTA catheter", is inserted into a blood vessel through a previously inserted guidewire, and the collapsed balloon is moved through the guidewire into the stenosed portion of the blood vessel while the position of the collapsed balloon is monitored by X-ray fluoroscopy or magnetic resonance imaging ("MRI"). The pressurized inflation fluid introduced into the inflation port at the proximal end of the PTA catheter then inflates the balloon, which in turn inflates the blood vessel and destroys the atherosclerotic lesion. However, application of the PTA method may lead to undesirable results and complications. Over inflation of the balloon can result in continued expansion of the undesirable blood vessels, which in turn can disrupt laminar flow within and near the expansion and lead to regrowth of new or treated atherosclerotic lesions. The localized forces created by balloon inflation can also cause rupture and tearing of the inner vessel walls, resulting in blood flowing into a false lumen or channel between the vessel walls, known as "dissection". In more severe cases, these local forces may lead to rupture, dissection, hematoma or pseudoaneurysms. The use of drug eluting PTA catheters may reduce the risk of certain types of PTA complications, but complications due to over-inflation and undesirably large localized forces generated during balloon inflation remain a significant problem associated with currently practiced PTA methods. The PTA catheter may be used within a support catheter for enhanced steering and vascular shielding purposes, the entire apparatus, hereinafter referred to as "PTA apparatus," including the guidewire, PTA catheter and support catheter, as well as additional components and features. The PTA device or system may be considered a first flexible tube slidably mounted on a guidewire within a second flexible tube. During use, the first and second tubes are moved relative to each other while the entire device is maneuvered within a generally curved biological vessel. As described below, these movements may be accompanied by various forces and deformations, which may exacerbate the risk of equipment failure and complicate the PTA catheter-based operation and procedure. For this reason, PTA instrument designers, developers and vendors, and PTA practitioners continue to search for improved PTA conduits, improved PTA plants, and improved PTA methods to reduce or eliminate the risk of various types of PTA complications.

Disclosure of Invention

Subsequently, embodiments of the present invention will be described in detail with reference to the accompanying drawings. It is noted that the embodiments do not limit the invention, but merely represent illustrative examples.

Drawings

Figures 1A-B show an atherosclerotic lesion,

figure 2 shows a PTA catheter which,

figures 3A-G illustrate inflation of the balloon of the PTA catheter,

figures 4A-B illustrate one class of embodiments of the presently disclosed improved PTA catheter and improved PTA apparatus,

figure 5 shows a hydraulically activated stabilizer in a cross-sectional view of a portion of a modified PTA device,

Figure 6 shows in cross section a multi-stabilizer embodiment of the improved PTA device,

figures 7A-C illustrate certain problems that occur when operating a PTA device during the PTA process,

fig. 8 illustrates another benefit of the stabilizer in the improved PTA apparatus.

Detailed Description

FIGS. 1A-B illustrate an atherosclerotic lesion. Fig. 1A shows a portion of a healthy normal artery. The artery 102 is shown in cross-section, partially transected 103, and then longitudinally dissected 104. The artery 102 includes an arterial wall 105 and a lumen 106 through which blood flows. The arterial wall comprises three main layers: (1) Adventitia 108, comprising a layer of connective tissue that anchors the artery to adjacent external tissue; (2) a medium 110 comprising smooth muscle cells; and (3) an inner membrane 112 comprising a plurality of layers including an innermost endothelial layer 114 forming an inner surface of the arterial wall. Fig. 1B shows an atherosclerotic lesion. Atherosclerotic lesions 120 occupy a sub-endothelial volume between the endothelium and the intimal lining. As described above, atherosclerotic lesions develop from the original fatty streak into complex matrices of various types of cells, cell residues, lipids, oxidized lipids, inorganic ions, and even invasive bacteria, often covered over time by fibrous layer 122 that may be calcified. Also as described above, the PTA method is used to destroy atherosclerotic lesions and reopen partially or fully occluded arterial lumens.

Fig. 2 shows a PTA catheter. The PTA catheter is representative of a more general family of expandable member instruments used in general percutaneous transluminal interventional procedures. PTA catheter 202 includes a manifold 204, an outer shaft 206, and a deflation balloon 208 at the distal end of the shaft. The shaft of the PTA catheter is shown inserted into the lumen of the support catheter 210 through a manifold 211 at the proximal end and over a guidewire 212. When an adjustable length balloon structure is desired, or in some cases, when additional guidance or shielding of the vessel is desired, the balloon is inserted into the support catheter. Transradial access or transfemoral access is used to introduce a catheter sheath into the vascular system. A guidewire is inserted through the introducer sheath and through the vasculature to and through the atherosclerotic lesion to be treated. The support catheter 210 is inserted over the guidewire and navigated to the desired location relative to the lesion. The PTA catheter is mounted on a guidewire and inserted into a support catheter to guide the balloon into position relative to the lesion, after which the balloon is inflated by introducing a pressurized liquid formed of contrast and saline into an inflation port 214, which inflation port 214 extends from the manifold and communicates with the balloon interior through the outer PTA catheter lumen.

Fig. 3A-G illustrate inflation of the balloon of the PTA catheter. In fig. 3A-G, a balloon-length adjustable PTA catheter is used as an example of a PTA catheter. Fig. 3A shows the open distal end of the support catheter 302 through which the guidewire 304 passes. The distal end of the support catheter is navigated to the appropriate location relative to the lesion to be treated. As shown in fig. 3B, the distal end of the shaft of the PTA catheter 306 is advanced along the guidewire toward the distal end 302 of the support catheter. As shown in fig. 3C, the distal end of the PTA catheter 306 is advanced further along the guidewire to a position flush with the distal end 302 of the support catheter. The deflated balloon 308 is fully visible in this view. The inflation fluid is introduced into the inflation port (214 in fig. 2) and flows under pressure through the PTA catheter inflation lumen 310 within the PTA catheter shaft 206, which PTA catheter shaft 206 is in open communication with the balloon 308. The PTA catheter shaft 206 extends further into the distal shaft portion 312. The guidewire 304 passes through an inner guidewire lumen 314 within the PTA catheter that is not in fluid communication with the PTA catheter inflation lumen. In certain embodiments, the inflation lumen may be coaxially disposed about the guidewire lumen. The lumen cross-section may be cylindrical or, in some embodiments, may have a more complex shape.

As shown in fig. 3D, the PTA catheter is advanced further along the guidewire such that a desired length or portion of the balloon 320 is exposed to the internal environment of the vessel through the distal end 302 of the support catheter. An inflation fluid is then introduced into the PTA catheter inflation lumen and pressurized to inflate the balloon portion exposed to the intravascular environment, as shown in fig. 3E. In this description, the inflated balloon has a cylindrical shape with relatively sharp edges 322 and 324 at the balloon shoulder to emphasize the length of the balloon inflated portion. However, in real world instruments, the inflated portion of the balloon is circular. In fig. 3F, the contracted balloon is advanced further along the guidewire prior to inflation so that the full length of balloon 320 may be subsequently inflated, as shown in fig. 3G. Accordingly, the length 326 of the inflation balloon may be adjusted by positioning the distal end of the PTA catheter shaft relative to the distal end of the support catheter. In conventional PTA instruments, the balloon is fully inflated without a support catheter as a constraining member, and adjustment of the balloon length is achieved by selecting one or more PTA catheters, each with a different but constant length balloon, prior to deployment during treatment.

Fig. 4A-B illustrate one class of embodiments of the presently disclosed improved PTA catheter and improved PTA apparatus. In fig. 4A, a portion of a modified PTA device is shown. The illustrated PTA device portion includes a distal end of a support catheter 402, a distal end of a PTA catheter 404 recessed within the support catheter, and a portion of a balloon 406 shown protruding outwardly from the support catheter and mounted on a PTA catheter 408 on a PTA catheter distal section. Furthermore, three as yet undeployed stabilizers 410-412 are shown at locations along the PTA catheter to the right of the portion of the balloon 408 mounted to the distal section of the PTA catheter. In fig. 4A, the balloon is unexpanded or minimally expanded.

Fig. 4B illustrates the PTA apparatus previously illustrated in fig. 4A, as described above, after inflation of the balloon by introducing a pressurized inflation fluid into the inflation lumen of the PTA catheter. In this case, balloon 406 has been radially expanded, as are stabilizers 410-412. The radial expansion of the stabilizer is constrained by the support catheter 402. However, as the balloon is inflated, radial expansion of the stabilizer continues to press the inflated portions of the stabilizer tightly against the support catheter, forming annular cylindrical bands 414-416. Thus, the pressure of the inflation fluid results in a series of compressed annular portions, bands, or O-ring ribs along the PTA catheter that fix both the translational position of the PTA catheter relative to the support catheter and the position and orientation of the PTA catheter shaft within the support catheter such that the apparent long axes of symmetry of the PTA catheter and the support catheter are coextensive, or in other words such that the PTA catheter and the support catheter are constrained by the stabilizer to remain coaxial. In this embodiment, the stabilizer is hydraulically activated by the same pressurized inflation fluid of the hydraulically activated balloon. Various embodiments use one to three, four, or more stabilizers. In the embodiment discussed with reference to fig. 4A-B, the stabilizer is hydraulically activated with the balloon. However, in alternative embodiments, the stabilizer may be activated alone by other means, including by additional mechanical stabilizer activation components, which may involve changing the relative rotational direction of the PTA catheter and the support catheter, for example, to rotate a cam-like stabilizer to a locked position, or to manipulate one or more additional mechanical activation components, such as an internal stabilizer activation tubular sheath.

Fig. 5 shows a hydraulically activated stabilizer in a cross-sectional view of a portion of a modified PTA device. The illustrated portion of the improved PTA apparatus includes a portion of a balloon 502, a support catheter 504, and a PTA catheter 506. The proximal portion of the balloon of length 508 is recessed within the support catheter. Most of this recessed portion of the balloon is secured to the outer surface of the distal section of the PTA catheter. The balloon may be secured to the PTA catheter by thermal, ultrasonic or laser welding, adhesives, mechanical tension, or other means. In many embodiments, the recessed portion of the balloon must be maintained to maintain the folding of the balloon so that the balloon can be collapsed and retracted into the support catheter prior to retracting or moving the PTA device intravascularly from the vessel. As described above, the PTA catheter includes an inflation lumen 510 and a guidewire lumen 512. As described above, the stabilizer in this embodiment is an endless belt, which in cross section appears as endless belt portions 514 and 516. At least one port 518 in the PTA catheter shaft allows inflation fluid from the inflation lumen to enter the annular chamber 520, which is formed between the central inflation portion of the annular band and the outer surface of the PTA catheter shaft. As described above with reference to fig. 4B, when pressurized inflation fluid is introduced into the inflation lumen, the annular chamber expands and presses the outer surface of a portion of the annular band against the inner surface of the support conduit, forming a compressed annular portion, band or O-ring rib that secures both the translational position of the PTA conduit relative to the support conduit and the placement of the PTA conduit within the support conduit in a coaxial position relative to the support conduit.

In the illustrated embodiment, the stabilizers 514 and 516 are strips of loop material separate from the balloon. In certain alternative embodiments, the stabilizer may be a portion of balloon material that is not bonded to the underlying PTA catheter shaft and covers one or more ports in the PTA catheter shaft such that when inflation fluid is pressurized within the inflation lumen of the PTA catheter, the annular protrusion is urged radially outward and against the inner surface of the support catheter. For each stabilizer, there may be one, two or more ports disposed along an annular band of the PTA catheter shaft that underlies the portion of the stabilizer that is outwardly expanded by the pressurized inflation fluid. In certain embodiments, the stabilizer material may have a different elasticity, deformability, or compliance than the balloon material. The difference in elasticity, deformability or compliance between the two different types of materials may be selected so that the stabilizer presses against the inner surface of the support catheter shaft at different predetermined points in time relative to a particular degree of balloon inflation. In other embodiments, the stabilizer material may have a different coefficient of friction relative to the balloon and/or support catheter material. Thus, depending on the material selected, the translational position of the PTA catheter may be fixed shortly after introduction of the pressurized inflation fluid into the inflation lumen and prior to inflation of the balloon, may instead be fixed at a point in time consistent with the degree of partial inflation of the balloon, or may be fixed at a point in time consistent with or subsequent to full inflation of the balloon. The elasticity, deformability, compliance or friction of the stabilizer material may vary even within the stabilizer, with the central portion of the stabilizer strap being softer and having greater elasticity such that the central portion of the stabilizer strap preferentially expands radially relative to the outer portions 522 and 523 of the strap. In the illustrated embodiment, the stabilizer material that is expanded to form the annular stabilizer band is not secured to the PTA catheter shaft by adhesive or welding, while the portions 522 and 523 at the stabilizer edges are secured to the PTA catheter shaft by adhesive, welding, mechanical tension, or other means. The stabilizer material may be selected from a range of materials including polymers, fibers and metals including elastomeric and/or hard plastic polymers, ductile, elastomeric and/or shape memory metals, and combinations of these materials.

Fig. 6 shows in cross section a multi-stabilizer embodiment of the improved PTA device. In this embodiment, there are at least three stabilizers 602-604 that are inflated by inflation fluid passing through at least three respective ports 606-608 in the PTA catheter shaft. As with the embodiment shown in fig. 5, the proximal portion of the balloon of length 610 is recessed within the support catheter 612 and a majority of the balloon portion is secured to the distal end of the PTA catheter. In the embodiment shown in fig. 6, the widths 614-616 of the endless stabilizer belts are equal to each other, but in alternative embodiments the widths and spacing distances of the stabilizer belts may vary. In addition, the elasticity, deformability, compliance, and/or coefficient of friction of the stabilizer material may also be varied to provide progressive activation of the stabilizer during balloon inflation.

Fig. 7A-C illustrate certain problems that occur when operating a PTA device in a PTA process. In fig. 7A, a first inner tubular member 702 within a second outer tubular member 704 is pushed upward relative to the outer tubular member, as indicated by arrow 706. Due to the different flexibility and dimensions of the two tubular elements, and due to the curvature of the outer tubular element, an upward force exerted on the inner tubular element may cause the inner tubular element to bend or kink relative to the outer tubular element. This can result in significant forces being applied by the inner tubular member to the outer tubular member at some locations associated with the kink (e.g., at kink 708), as well as greater separation of the inner tubular member from the outer tubular member at other locations (e.g., at location 710). These very varying forces result in frictional forces that require the application of excessive forces to continue to move the inner tubular member upwardly relative to the outer tubular member, stored mechanical energy, and uneven translation of the inner tubular member relative to the outer tubular member with the application of constant upward forces, as well as various derivative forces that may cause localized deformation of the two tubular member shapes. Similarly, as shown in fig. 7B, when the inner tubular member is retracted by downward force, as indicated by arrow 712, the inner tubular member may eventually exert a greater force on the outer tubular member than at other locations, such as location 718, and at certain locations, such as location 716. These different forces applied at different locations again result in local deformation of the shape of one or both of the tubular elements, abrupt and undesired release of stored mechanical energy, and uneven translation of the inner tubular element relative to the outer tubular element with a constant downward force applied to the inner tubular element. Fig. 7C illustrates the benefits provided by the stabilizer described above. In fig. 7C, circles 720-724 represent activated stabilizers that constrain the inner tubular member 702 to remain generally coaxially positioned relative to the outer tubular member 704. As a result, many of the kinks, bands, and distortions discussed with reference to fig. 7A-B are prevented. Smooth translation of the PTA catheter of an inner tubular element like that of fig. 7A-C relative to an outer tubular element like that of fig. 7A-C is critical in the PTA procedure. Excessive applied forces, stored mechanical energy, and other such problems can lead to many of the various deleterious effects and consequences described above, including equipment failure, lack of accuracy, handling difficulties, equipment misalignment, and vascular damage. Thus, when fully activated, the stabilizer applies sufficient radial force to fix the relative translational position of the PTA catheter and the support catheter, and when partially activated, e.g., when the balloon is partially inflated, the stabilizer maintains the relative coaxial arrangement of the PTA catheter within the support catheter to promote smooth translation of the PTA catheter relative to the support catheter and prevent deformation of the PTA device during intravascular, particularly bending intravascular, movement. In addition, when the stabilizer is partially or fully engaged with the support catheter, strain or force exerted on the support catheter and surrounding blood vessel walls during push or pull operation of the PTA catheter is reduced or prevented.

Fig. 8 illustrates another benefit of the stabilizer in the improved PTA apparatus. Fig. 8 shows in cross-section a portion of a PTA device similar to the portion shown in fig. 5 within biocontainers 802 and 804. The distal portions of support catheters 806 and 808 are positioned within the blood vessel. When the balloons 810 and 812 are inflated to conform to the inner surfaces of the blood vessels 818 and 820 and apply force to the vessel walls, the balloons are constrained within the distal portions of the support catheters 814 and 816 and then radially expand from a first diameter 822 within the support catheter to a second diameter 824 outside the support catheter. Inflation of the balloon results in a force 826 that is approximately parallel to the average linear portion of the balloon's curved surface between the support catheter and the vessel, which force 826 may be resolved into a lateral or axial force 828 and a vertical or radial force 830. Of course, the portion of the balloon between the support catheter and the vessel approximates a conical section, so that the radial forces lie in an annular section of an imaginary planar disc perpendicular to the axis of symmetry of the support catheter and vessel, while the axial forces lie in an imaginary cylindrical continuation of the inner surface of the support catheter. During inflation, the axial and radial forces may exert large stresses on the attachment of the balloon to the PTA catheter. Further, radial forces tend to fix the position of the PTA catheter relative to the support catheter, while axial forces tend to pull the PTA catheter out of the support catheter, resulting in lengthening the inflated portion of the balloon. One way to stabilize the PTA catheter within the support catheter during balloon inflation is to use a wider concave portion of the balloon along the distal portion of the PTA catheter in order to increase the radial force applied to the support catheter, as indicated by small radial arrows 832. However, as described above, the use of a stabilizer may instead provide the additional radial force required to counteract the axial force generated by balloon inflation. The stabilizer may also help distribute radial forces against the support catheter over a greater length of the support catheter shaft to prevent deformation of the distal end of the support catheter due to inflation forces resulting from balloon inflation.

While the invention has been described in terms of specific embodiments, it is not intended that the invention be limited to those embodiments. For example, a variety of different materials may be used for the hydraulically activated stabilizer, with different elasticity and deformability. As described above, the plurality of stabilizers may be formed from a single wide band or sleeve of stabilizer material. Different numbers of circularly arranged ports may be used for inflation of a particular stabilizer.

Further examples of the present disclosure are provided below:

1. a percutaneous transluminal angioplasty ("PTA") device, comprising:

a guide wire;

supporting the catheter; and

a PTA conduit inserted into the support conduit, the PTA conduit having:

the distal end of the tube is provided with a proximal end,

the proximal end of the tube is provided with a proximal end,

an outer shaft which,

a catheter balloon mounted at the distal end,

an inflation lumen in fluid communication with the interior volume of the catheter balloon,

a guidewire lumen through which a guidewire passes, and

one or more stabilizers, when activated, fix the position of the PTA catheter within the support catheter, preferably through the inflation lumen, and constrain the PTA catheter to a coaxial arrangement relative to the support catheter.

2. The PTA apparatus according to claim 1, wherein the support catheter has a tubular shaft of a first diameter that is open at a distal end and open at a proximal end to a manifold.

3. The PTA apparatus according to claim 2, wherein the PTA conduit further comprises:

a manifold mounted at the proximal end of the outer shaft;

an expansion port providing fluid communication through the manifold to the expansion lumen; and

a guidewire port through which a guidewire is inserted into the guidewire lumen.

4. The PTA apparatus of any of claims 1-3, wherein the one or more stabilizers each comprise:

a strip of stable elastomeric material mounted on the surface of the PTA catheter shaft; and

one or more inflation fluid ports located below the central portion of the stabilizer elastic material strip.

5. The PTA apparatus according to claim 4,

wherein the central portion of the stabilizer elastic material strip is not secured to the outer surface of the PTA catheter shaft;

wherein the two edge portions of the stabilizer elastic material strip are secured to the outer surface of the PTA catheter shaft, an expandable annular inflation fluid chamber being formed between the center portion of the stabilizer elastic material strip and the underlying outer surface of the PTA catheter shaft and the one or more inflation fluid ports.

6. The PTA apparatus according to claim 5, wherein when pressurized inflation fluid is introduced into the inflation lumen of the PTA catheter and the pressurized inflation fluid flows into the annular inflation fluid chamber through the inflation fluid port, the inflation fluid chamber is adapted to expand radially outward, the stabilizer being pressed against the inner surface of the support catheter shaft by the pressurized inflation fluid.

7. The PTA apparatus according to claim 6, wherein the stabilizer elastic material strips are separated from PTA catheter balloons and from stabilizer elastic material strips of other stabilizers.

8. The PTA apparatus according to claim 6 or 7, wherein the stabilizer elastic material strip is part of a strip of a portion of stabilizer elastic material forming two or more adjacent stabilizers along the PTA catheter shaft, each stabilizer covering one or more inflation fluid ports in the PTA catheter shaft.

9. The PTA apparatus according to any of claims 6 to 8, wherein the PTA catheter shaft comprises two or more stabilizers, each stabilizer comprising a stabilizer elastic material strip having a different elasticity, deformability and/or compliance than one or more strips of other stabilizers, such that the stabilizers are fully activated at different points in time when inflation fluid is introduced into the inflation lumen of the PTA catheter.

10. The PTA apparatus according to any of claims 6 to 9, wherein the stabilizer elastic material strip has elasticity, deformability and/or compliance different from that of the PTA catheter balloon, such that the stabilizer is fully inflated at a point in time different from that of the PTA catheter balloon being fully inflated.

11. The PTA apparatus according to claim 10, wherein the stabilizer is adapted to be inflated prior to inflation of the PTA catheter balloon portion.

12. The PTA apparatus according to claim 10, wherein the stabilizer is adapted to expand upon inflation of the PTA catheter balloon portion.

13. The PTA apparatus according to claim 10, wherein the stabilizer is adapted to expand when the PTA catheter balloon is fully inflated.

14. The PTA apparatus according to claim 10, wherein the stabilizer is adapted to expand after full inflation of the PTA catheter balloon.

15. The PTA apparatus according to claim 10, wherein the stabilizer is adapted to expand with a portion of a PTA catheter balloon that is recessed within the support catheter, resulting in a combination of radial forces of the recessed PTA balloon portion and stabilizer that are applied to the support catheter that counteract axial forces generated by balloon expansion, thereby fixing the position of the PTA catheter relative to the support catheter and constraining the PTA catheter in a coaxial arrangement relative to the support catheter.

16. The PTA apparatus according to claim 10, wherein the stabilizer is adapted to expand with a PTA catheter balloon recessed within the support catheter, resulting in a combination of radial forces of the recessed PTA balloon and stabilizer applied to the support catheter, fixing the position of the PTA catheter relative to the support catheter, thereby reducing or preventing strain or force that is otherwise applied during push or pull operation of the PTA catheter.

17. A method of treating a lesion in a blood lumen of a patient, the method comprising:

introducing a guidewire into the blood lumen;

introducing a support catheter into the blood lumen over the guidewire;

introducing a PTA catheter with one or more stabilizers into a support catheter over the guidewire; and

one or more stabilizers are activated to fix the position of the PTA catheter within the support catheter and constrain the PTA catheter to a coaxial arrangement relative to the support catheter.

18. The method according to claim 17,

wherein the support catheter has a tubular shaft of a first diameter, the tubular shaft being open at a distal end and open at a proximal end to a manifold; and is also provided with

Wherein the PTA catheter further comprises:

-a manifold mounted at the proximal end of the outer shaft;

-an expansion port providing fluid communication through a manifold to an expansion lumen; and

-a guidewire port through which a guidewire is inserted into a guidewire lumen.

19. The method of claim 18, wherein the one or more stabilizers each comprise:

-a strip of stable elastomeric material mounted on the surface of the PTA catheter shaft; and

-one or more inflation fluid ports located below the central portion of the stabilizer elastic material strip.

20. The method according to claim 19,

21. The method of claim 20, wherein when the pressurized inflation fluid is introduced into the inflation lumen of the PTA catheter, the pressurized inflation fluid flows into the annular inflation fluid chamber through the inflation fluid port and expands the inflation fluid chamber radially outward, pressing the stabilizer against the inner surface of the support catheter shaft.

22. The PTA apparatus according to any of claims 1 to 16, for use in treating a lesion within a blood lumen of a patient.

23. A catheter system comprising or consisting of:

a first catheter having a first lumen surrounded by a first catheter shaft, preferably having a uniform circumference and/or diameter; and

a second catheter inserted into the first lumen of the first catheter, and

the second catheter has a second lumen surrounded by a second catheter shaft, and one or more hydraulically expandable stabilizers in fluid communication with the second lumen, and wherein the one or more stabilizers are adapted to form a radially outwardly expandable inflation fluid chamber upon hydraulic expansion through the second lumen, thereby pressing the stabilizers against the inner surface of the first catheter shaft and fixing the position of the second catheter within the first catheter and constraining the second catheter to a coaxial arrangement relative to the first catheter.

24. The catheter system of claim 23, wherein the first catheter is a support catheter or a guide catheter and/or the second catheter is a balloon catheter, another guide catheter, a percutaneous transluminal angioplasty catheter, a dilator catheter, a crossing catheter or a microcatheter.

25. Catheter system according to claim 23 or 24, wherein the one or more stabilizers are made of an elastic material, preferably an elastomer.

26. The catheter system of any of the foregoing claims, wherein the one or more stabilizers each have an edge portion and a center portion, wherein the edge portion is secured to an inner or outer surface of the second catheter shaft, and wherein the center portion is not secured to the inner or outer surface of the second catheter shaft.

27. The catheter system of any one of claims 23-26, wherein the second lumen of the second catheter has one or more inflation fluid ports, each port covered by a central portion of one stabilizer.

28. Catheter system according to any one of claims 23 to 27, having two or more stabilizers, wherein each stabilizer is made of a different elastic material, preferably having a different coefficient of friction, elasticity, deformability and/or compliance.

29. The catheter system according to any one of claims 23 to 28, wherein the elastic material of the central portion of the stabilizer is more flexible and/or has a greater elasticity than the elastic material of the edge portions of the stabilizer.

30. A percutaneous transluminal angioplasty device, comprising:

supporting the catheter; and

a percutaneous transluminal angioplasty catheter inserted into a support catheter, the percutaneous transluminal angioplasty catheter having:

a distal end and a catheter balloon mounted to the distal end,

the inner cavity is expanded in such a way that,

-a guidewire lumen, and

one or more hydraulic expansion stabilizers,

wherein the inflation lumen is in fluid communication with the interior volume of the catheter balloon and the one or more hydraulic inflation stabilizers.

31. The percutaneous transluminal angioplasty device of claim 30, wherein the one or more stabilizers each comprise:

a stabilizer elastic material strip mounted on a surface of a percutaneous transluminal angioplasty catheter shaft; and

32. The percutaneous transluminal angioplasty device of claim 30 or 31, wherein the central portion of the stabilizer elastic material strip is not fixed to the outer surface of the percutaneous transluminal angioplasty catheter shaft;

Wherein the two edge portions of the stabilizer elastic material strip are secured to the outer surface of the percutaneous transluminal angioplasty catheter shaft, an expandable annular inflation fluid chamber is formed between the central portion of the stabilizer elastic material strip and the underlying outer surface of the percutaneous transluminal angioplasty catheter shaft and the one or more inflation fluid ports.

33. The percutaneous transluminal angioplasty device of claim 32, wherein when a pressurized inflation fluid is introduced into the inflation lumen of the percutaneous transluminal angioplasty catheter and the pressurized inflation fluid flows into the annular inflation fluid chamber through the inflation fluid port, the inflation fluid chamber is adapted to expand radially outwardly, pressing the stabilizer against the inner surface of the support catheter shaft by the pressurized inflation fluid.

34. The percutaneous transluminal angioplasty device of any one of claims 30 to 33, wherein the stabilizer elastic material strip is part of a strip forming part of the stabilizer elastic material of two or more adjacent stabilizers along the percutaneous transluminal angioplasty catheter shaft, each stabilizer covering one or more inflation fluid ports in the percutaneous transluminal angioplasty catheter shaft.

35. The percutaneous transluminal angioplasty device of any one of claims 30-33, wherein the percutaneous transluminal angioplasty catheter shaft comprises two or more stabilizers, each comprising a stabilizer elastic material strip having an elasticity, deformability, and/or compliance that is different than one or more strips of other stabilizers and/or different than the material of the percutaneous transluminal angioplasty catheter balloon.

36. The percutaneous transluminal angioplasty device of any one of claims 1-16 or 30-34, wherein the elastic material of the stabilizer, preferably the elastic material of the central portion of the stabilizer, is more flexible and/or has a greater elasticity than the elastic material of the percutaneous transluminal angioplasty catheter balloon.

37. The percutaneous transluminal angioplasty device of any one of claims 1-16 or 30-36, wherein the support catheter has a shaft of uniform circumference and/or diameter.

Claims

1. A catheter system comprising or consisting of:

a second catheter inserted into the first lumen of the first catheter, and

2. The catheter system of claim 1, wherein the first catheter is a support catheter or a guide catheter and/or the second catheter is a balloon catheter, another guide catheter, a percutaneous transluminal angioplasty catheter, a dilator catheter, a crossing catheter or a microcatheter.

3. Catheter system according to claim 1 or 2, wherein the one or more stabilizers are made of an elastic material, preferably an elastomer.

4. The catheter system of any of the foregoing claims, wherein the one or more stabilizers each have an edge portion and a central portion, wherein the edge portion is secured to an inner or outer surface of the second catheter shaft, and wherein the central portion is not secured to the inner or outer surface of the second catheter shaft.

5. The catheter system of any of the preceding claims, wherein the second lumen of the second catheter has one or more inflation fluid ports, each covered by a central portion of one stabilizer.

6. Catheter system according to any of the preceding claims, having two or more stabilizers, wherein each stabilizer is made of a different elastic material, preferably having a different coefficient of friction, elasticity, deformability and/or compliance.

7. The catheter system according to any of the preceding claims, wherein the elastic material of the central portion of the stabilizer is more flexible and/or has a greater elasticity than the elastic material of the edge portions of the stabilizer.

8. A percutaneous transluminal angioplasty device, comprising:

supporting the catheter; and

a distal end and a catheter balloon mounted to the distal end,

the inner cavity is expanded in such a way that,

-a guidewire lumen, and

one or more hydraulic expansion stabilizers,

9. A percutaneous transluminal angioplasty device, comprising:

a guide wire;

supporting the catheter; and

at the distal end of the tube,

at the proximal end of the tube,

the outer shaft is provided with a plurality of grooves,

a catheter balloon mounted at the distal end,

a guidewire lumen through which a guidewire passes, and

one or more stabilizers, when activated by the inflation lumen, fix the position of the percutaneous transluminal angioplasty catheter within the support catheter and constrain the percutaneous transluminal angioplasty catheter to a coaxial arrangement relative to the support catheter.

10. The PTA apparatus according to claim 8 or 9, wherein the support conduit has a tubular shaft of a first diameter that opens at the distal end and opens at the proximal end into a manifold.

11. The PTA apparatus according to any of claims 8 to 10, wherein the PTA conduit further comprises:

a manifold mounted to a proximal end of the outer shaft;

12. The percutaneous transluminal angioplasty device of claim 8 or 9, wherein the one or more stabilizers each comprise:

13. The PTA apparatus according to claim 12, wherein a central portion of the stabilizer elastic material strip is not fixed to an outer surface of the PTA catheter shaft;

14. The PTA apparatus according to claim 13, wherein the expansion fluid chamber is adapted to expand radially outward when the pressurized expansion fluid is introduced into the expansion lumen of the PTA catheter and the pressurized expansion fluid flows into the annular expansion fluid chamber through the expansion fluid port, the stabilizer being pressed against the inner surface of the support catheter shaft by the pressurized expansion fluid.

15. The PTA apparatus according to any of claims 12 to 14, wherein the stabilizer elastic material strips are separated from the PTA catheter balloon and from stabilizer elastic material strips of other stabilizers.

16. The PTA apparatus according to claims 12-15, wherein the stabilizer elastic material strip is part of a strip forming part of the stabilizer elastic material of two or more adjacent stabilizers along the PTA catheter shaft, each stabilizer covering one or more inflation fluid ports in the PTA catheter shaft.

17. The PTA apparatus according to any of claims 12 to 15, wherein the PTA catheter shaft comprises two or more stabilizers, each comprising a stabilizer elastic material strip having a different elasticity, deformability and/or compliance than one or more strips of other stabilizers, such that when inflation fluid is introduced into the inflation lumen of the PTA catheter, stabilizers are fully activated at different points in time.

18. The PTA apparatus according to any of claims 12 to 16, wherein the stabilizer elastic material strip has elasticity, deformability and/or compliance different from that of the PTA catheter balloon, such that the stabilizer is fully inflated at a point in time different from that when the PTA catheter balloon is fully inflated.

19. The PTA apparatus according to claim 18, wherein the stabilizer is adapted to expand prior to partial expansion of the PTA catheter balloon.

20. The PTA apparatus according to claim 18, wherein the stabilizer is adapted to expand when the PTA catheter balloon portion is inflated.

21. The PTA apparatus according to claim 18, wherein the stabilizer is adapted to expand when the PTA catheter balloon is fully inflated.

22. The PTA apparatus according to claim 18, wherein the stabilizer is adapted to expand after the PTA catheter balloon is fully inflated.

23. The PTA apparatus according to claim 18, wherein the stabilizer is adapted to expand with a portion of a PTA catheter balloon that is recessed within the support catheter, thereby creating a combination of recessed PTA balloon portions and radial forces of the stabilizer that are applied to the support catheter, counteracting axial forces created by balloon expansion, thereby fixing the position of the PTA catheter relative to the support catheter, and constraining the PTA catheter to a coaxial arrangement relative to the support catheter.

24. The PTA apparatus according to claim 18, wherein the stabilizer is adapted to expand with a PTA catheter balloon recessed within the support catheter, resulting in a combination of radial forces of the recessed PTA balloon and stabilizer applied to the support catheter, fixing the position of the PTA catheter relative to the support catheter, thereby reducing or preventing additional applied strain or force during push or pull operation of the PTA catheter.

25. The percutaneous transluminal angioplasty device of any one of claims 8-11, wherein the central portion of the stabilizer elastic material strip is not fixed to the outer surface of the percutaneous transluminal angioplasty catheter shaft; and wherein the edge portion of the stabilizer elastic material strip is secured to the outer surface of the percutaneous transluminal angioplasty catheter shaft, an expandable annular inflation fluid chamber being formed between the central portion of the stabilizer elastic material strip and the underlying outer surface of the percutaneous transluminal angioplasty catheter shaft and the one or more inflation fluid ports.

26. The percutaneous transluminal angioplasty device of claim 25, wherein when the pressurized inflation fluid is introduced into the inflation lumen of the percutaneous transluminal angioplasty catheter and the pressurized inflation fluid flows into the annular inflation fluid chamber through the inflation fluid port, the inflation fluid chamber is adapted to expand radially outwardly, pressing the stabilizer against the inner surface of the support catheter shaft by the pressurized inflation fluid.

27. The percutaneous transluminal angioplasty device of any one of claims 8-25, wherein the percutaneous transluminal angioplasty catheter shaft comprises two or more stabilizers, each comprising a stabilizer elastic material strip having an elasticity, deformability, and/or compliance that is different than one or more strips of other stabilizers and/or different than the material of the percutaneous transluminal angioplasty catheter balloon.

28. The percutaneous transluminal angioplasty device of any one of claims 8 to 26, wherein the elastic material of the stabilizer, preferably the elastic material of the central portion of the stabilizer, is more flexible and/or has a greater elasticity than the elastic material of the percutaneous transluminal angioplasty catheter balloon.