Patent Application
20050177185
The present invention pertains generally to the field of embolic protection. More typically, the present invention pertains to sheaths used for delivery or retrieval of embolic protection filters.
Intravascular devices such as embolic protection filters are generally placed within the lumen of a blood vessel or artery to filter embolic debris dislodged during a therapeutic procedure such as percutaneous transluminal coronary angioplasty (PCTA), percutaneous extraction atherectomy or stent delivery. To filter the dislodged embolic debris, an embolic protection filter can be placed distally of the therapeutic device (e.g. an angioplasty or atherectomy catheter) and deployed within the patient's vessel or artery. The filter is often delivered to the target site in a delivery sheath and removed using a retrieval sheath.
The present invention relates generally to the field of embolic protection filters. In an exemplary embodiment, a counterwound coil assembly can be incorporated into a delivery or retrieval sheath before the embolic protection filter. In one embodiment, the counterwound coil assembly is disposed at the distal end of a shaft. In an alternate embodiment, the counterwound coil assembly extends substantially to the full length of the delivery or retrieval sheath.
The following description should be read with reference to the drawings, in which like elements in different drawings are numbered in like fashion. Drawings, which are not necessarily to scale, are depict selected embodiments and are not intended to limit the scope of the invention. Although examples of construction, dimensions, and materials and manufacturing processes are illustrated for the various elements, those skilled in the art will recognize that many of the examples provided have suitable alternatives that may be utilized.
Sheath 10 can include an elongate shaft 20 defining a lumen 21. At the distal end of elongate shaft 20 can be disposed inner coil 22 and outer coil 24. Inner coil 22 and outer coil 24 can be sandwiched between inner tube 26 and outer tube 28. Coils 22 and 24 can be counterwound and multifilar as shown in
Shaft 20 can be formed from, for example, a polymeric material such as polypropylene (PP), polyvinylchloride (PVC), polytetrafluoroethylene (PTFE), polyether block amide (PEBA) or other suitable material. Shaft 14, struts 16, filter material 18 and inner and outer coils 22 and 24 respectively may be formed from a metallic material such as stainless steel, platinum, a nickel-titanium alloy or other suitable metal. In the case of filter 18, the metal may be in a form of a wire mesh. Alternately, filter 18 may include a microporous membrane made from a polymeric material such as polypropylene (PP), polyurethane, polyethylene terapthlalate, polyether-ether ketone (PEEK), polyether block amide (PEBA), polyamide (nylon), polyvinylchloride (PVC), polytetrafluoroethylene (PTFE) or any mixture, blend or combination thereof, or other suitable material.
Having thus described the several embodiments to the present invention, those skilled in the art will readily appreciate that other embodiments may be made and used that fall within the scope of claims attached hereto. Numerous advantages of the invention covered by this document have been set forth in the foregoing description. It will be understand that this disclosure is, in many respects, only illustrative. Changes may be made in detail, particularly in matters of shape, size and arrangement of parts without exceeding the scope of the invention.
