FLEXIBLE TUBE FOR CARTRIDGE FILTER
This application is a continuation application of U.S. application Ser. No. 10/373,482, as filed on Feb. 24, 2003, now U.S. Pat. No. 6,828,291.
FIELD OF THE INVENTION
The present invention pertains to embolic protection filters. More particularly, the present invention pertains to filters coupled to a shaft having desirable flexibility and trackability characteristics.
Heart and vascular disease are major problems in the United States and throughout the world. Conditions such as atherosclerosis result in blood vessels becoming blocked or narrowed. This blockage can result in lack of oxygenation of the heart, which has significant consequences since the heart muscle must be well oxygenated in order to maintain its blood pumping action.
Occluded, stenotic, or narrowed blood vessels may be treated with a number of relatively non-invasive medical procedures including percutaneous transluminal angioplasty (PTA), percutaneous transluminal coronary angioplasty (PTCA), and atherectomy. Angioplasty techniques typically involve the use of a balloon catheter. The balloon catheter is advanced over a guidewire such that the balloon is positioned adjacent a stenotic lesion. The balloon is then inflated and the restriction of the vessel is opened. During an atherectomy procedure, the stenotic lesion may be mechanically cut away from the blood vessel wall using an atherectomy catheter.
During angioplasty and atherectomy procedures, embolic debris can be separated from the wall of the blood vessel. If this debris enters the circulatory system, it could block other vascular regions including the neural and pulmonary vasculature. During angioplasty procedures, stenotic debris may also break loose due to manipulation of the blood vessel. Because of this debris, a number of devices, termed embolic protection devices, have been developed to filter out this debris.
The present invention pertains to embolic protection filtering devices. In at least some embodiments, the filtering device may include a filter cartridge having a filter coupled thereto. The filter cartridge may be configured to be slidable over a medical device, for example a guidewire, and may have desirable flexibility, trackability, and other features and/or characteristics as described in more detail below.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of an example embolic protection filtering device;
FIG. 2 is a perspective view of another example filter cartridge;
FIG. 3 is a perspective view of another example filter cartridge;
FIG. 4 is a perspective view of another example filter cartridge;
FIG. 5 is a perspective view of another example filter cartridge;
FIG. 6 is a perspective view of an example mandrel; FIG. 7 is a cross-sectional view taken through line 7-7;
FIG. 8 is an alternative cross-sectional view taken through line 7-7; and
FIG. 9 is a perspective view of another example mandrel.
5 DETAILED DESCRIPTION
The following description should be read with reference to the drawings wherein like reference numerals indicate like elements throughout the several views. The detailed descrip
10 tion and drawings illustrate example embodiments of the claimed invention.
FIG. 1 illustrates an example embolic protection filtering device 10. Device 10 may include a tubular filter cartridge 12 having a filter 14 coupled thereto. Filter cartridge 12 may
15 have desirable flexibility, trackability, and/or other characteristics that allow it to be exchanged over other medical devices such as a guidewire 16 (as shown in FIG. 1), a catheter, and the like. Moreover, because a number of the features and characteristics of filter cartridge 12 can be varied, cartridge 12 can be
20 configured to be slidable over essentially any medical device, including virtually all commercially available guidewires and catheters.
Filter cartridge 12 may be comprised of a number of different materials including metals, metal alloys, polymers, or
25 the like, or combinations or mixtures thereof. For example, filter cartridge 12 may be comprised of super elastic, linear elastic, and/or shape memory metals and/or metal alloys. Some examples of suitable metals and metal alloys include stainless steel, such as 304v stainless steel; such as nickel
30 titanium alloy, such as nitinol, nickel-chromium alloy, nickel chromium-iron alloy, cobalt alloy, titanium and/or titanium alloys, or the like; or other suitable material.
Some examples of suitable polymers may include polytetrafluoroethylene (PTFE), ethylene tetrafluoroethylene
35 (ETFE), fluorinated ethylene propylene (FEP), polyurethane, polypropylene (PP), polyvinylchloride (PVC), polyether-ester (for example a polyether-ester elastomer such as ARNITEL® available from DSM Engineering Plastics), polyester (for example a polyester elastomer such as HYTREL® avail
40 able from DuPont), polyamide (for example, DURETHAN® available from Bayer or CRISTAMID® available from Elf Atochem), elastomeric polyamides, block polyamide/ethers, polyether block amide (PEBA, for example available under the trade name PEBAX®), silicones, polyethylene, Marlex
45 high-density polyethylene, Marlex low-density polyethylene, linear low density polyethylene (for example REXELL®), polyethylene terephthalate (PET), polyetheretherketone (PEEK), polyimide (PI), polyetherimide (PEI), polyphenylene sulfide (PPS), polyphenylene oxide (PPO), polysul
50 fone, nylon, perfluoro(propyl vinyl ether) (PFA), other suitable materials, or mixtures, combinations, or copolymers thereof. In some embodiments filter cartridge 12 can include a liquid crystal polymer (LCP) blended with other polymers to enhance torqueability. By employing selection of materials
55 and processing techniques, thermoplastic, solvent soluble, and thermosetting variants of these and other materials can be employed to achieve the desired results.
In some embodiments, a coating, for example a lubricious, a hydrophilic, a protective, or other type of coating may be
60 applied over portions or all of filter cartridge 12, or other portions of device 10. Hydrophobic coatings such as fluoropolymers provide a dry lubricity which improves guidewire handling and device exchanges. Lubricious coatings improve steerability and improve lesion crossing capability. Suitable
65 lubricious polymers are well known in the art and may include silicone and the like, hydrophilic polymers such as polyarylene oxides, polyvinylpyrolidones, polyvinylalco