BALLOON CATHETER WITH HYDROGEL COATING

Abstract

The invention relates to a balloon catheter (1) to be introduced into the blood vessel system of the human or animal body, said catheter having a longitudinally extending shaft (2), with the balloon catheter (1) comprising a distal portion (A) in which a balloon (3) is arranged that is expandable by the supply of a fluid through a lumen (9) extending through the shaft (2), with the distal tip (8) of the balloon catheter (1) being provided with a coating consisting of a hydrogel (7). The invention provides a balloon catheter (1) capable of easily passing through constricted areas in blood vessels.

Claims

1. Balloon catheter to be introduced into the blood vessel system of the human or animal body, said catheter having a longitudinally extending shaft, with the balloon catheter comprising a distal portion in which a balloon is arranged that is expandable by the supply of a fluid through a lumen extending through the shaft, wherein the balloon catheter has a distal tip that is provided with a coating consisting of a hydrogel, wherein the area of the coating with hydrogel, viewed in the longitudinal direction, extends from the distal end of the balloon catheter to maximally the middle of the balloon.

2-3. (canceled)

4. Balloon catheter according to claim 1, wherein the area of the coating with hydrogel, viewed in the longitudinal direction, maximally covers the distal third of the balloon.

5. Balloon catheter according to claim 1, wherein the length of the area of the balloon catheter coated with hydrogel amounts to maximally 5 cm.

6. Balloon catheter according to claim 1, wherein the amount of hydrogel per coated unit area of the balloon catheter amounts to ≤2.5 μg/mm.sup.2.

7. Balloon catheter according to claim 1, wherein the total amount of hydrogel applied to the balloon catheter amounts to ≤5 mg.

8. Balloon catheter according to claim 1, wherein the hydrogel is free of active substances.

9. Balloon catheter according to claim 1, wherein the hydrogel comprises a polysaccharide, a modified polysaccharide, a methacrylate, a polypeptide, a protein or a synthetic polymer.

10. Balloon catheter according to claim 1, wherein the hydrogel comprises dextran, polyhydroxyethyl methacrylate, a polyacrylate, chitosan, oxidized cellulose, polyvinylpyrrolidone, polyethylene glycol, hyaluronic acid, agarose, starch, starch derivatives such as hydroxyethyl starch, a poloxamer, gelatin, fibrin, polyvinyl alcohol, propylene glycol, polyacrylic acid, methyl cellulose, carboxymethyl cellulose, hydroxypropyl methyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, alginate, amylose, amylopectin, xanthan, xyloglucan, peptidoglycan, polyoxyethylene derivatives, a silicone or elastin.

11. Balloon catheter according to claim 1, wherein a second lumen extends at least partially through the shaft in the longitudinal direction, said second lumen serving to accommodate a guidewire.

12. Balloon catheter according to claim 1, wherein the balloon is coated with one or several active substances.

13. Balloon catheter according to claim 12, wherein the active substance or agent used is selected from the following group: Tretinoin, orphan receptor agonists, elafin derivatives, corticosteroids, steroid hormones, paclitaxel, rapamycin, tacrolimus, hydrophobic proteins, heparin or hormone-like or cell proliferation-modifying substances.

14. Balloon catheter according to claim 1, wherein one or several Luer lock connectors are arranged adjacent to the proximal end of the shaft.

15. Balloon catheter according to claim 4, wherein the coating with hydrogel is confined to the distal tip of the balloon catheter.

16. Balloon catheter according to claim 5, wherein the length of the area of the balloon catheter coated with hydrogel amounts to maximally 3 cm.

17. Balloon catheter according to claim 16, wherein the length of the area of the balloon catheter coated with hydrogel amounts to maximally 2 cm.

18. Balloon catheter according to claim 6, wherein the amount of hydrogel per coated unit area of the balloon catheter amounts to 0.5 to 2.5 μg/mm.sup.2.

19. Balloon catheter according to claim 7, wherein the total amount of hydrogel applied to the balloon catheter amounts to ≤3 mg.

20. Balloon catheter according to claim 19, wherein the total amount of hydrogel applied to the balloon catheter amounts to ≤1 mg.

Description

[0033] Further elucidation of the invention is provided through the enclosed figures by way of examples, where

[0034] FIG. 1: is a side view of the balloon catheter according to the invention;

[0035] FIG. 2 is a longitudinal section of the distal portion of the shaft of the balloon catheter shown in FIG. 1.

[0036] In FIG. 1, the balloon catheter 1 proposed by the invention is shown in side view, where in the representation chosen here right means proximal and left means distal.

[0037] The balloon catheter 1 comprises a shaft 2 extending in longitudinal direction, the outer diameter of said shaft being larger in the proximal section 6, of which only a short segment is shown here, than further distally. The section of the shaft 2 in which the balloon 3 is located is identified by the letter A. The balloon 3 is shown in the unexpanded but not folded state. A first lumen for the fluid delivery as well as a second lumen for accommodation of the guidewire extend through the shaft 2 (not shown here), with each of the two lumens being formed by a tube. Distal to the balloon 3, the distal tip 8 can be seen.

[0038] Proximally, two catheter hubs in the form of luer-lock connections 4, 5 are arranged at the proximal section 6 of the shaft 2, with connection 4 serving to deliver fluid into the first lumen by means of a balloon dilator and connection 5 serving to introduce the guidewire into the second lumen.

[0039] In FIG. 2, only the distal part of the shaft 2 is shown. A first lumen 9 is configured to accommodate the second lumen 10, that is, the second lumen 10 extends longitudinally through the first lumen 9. The first lumen 9 is in contact at its distal end with the balloon 3, which can be expanded by supplying fluid through the first lumen 9. The second lumen 10, on the other hand, has an opening at the distal end and is used to accommodate the guidewire, which is not shown here.

[0040] The distal tip 8 is located at the distal end of the shaft 2. Said tip is coated radially, i.e. over its circumference, with a hydrogel 8. The applied coating of hydrogel 8 may extend marginally over the balloon 3, but this is not mandatory; rather, it is advantageous for the hydrogel coating 8 to be primarily confined to the distal tip 8. When the balloon catheter 1 is passing through a constricted area in the blood vessel, the hydrogel coating 8 automatically spreads partially further proximally in the longitudinal direction, so that good lubricity and advanceability of the balloon catheter 1 is ensured.