Patent Application: US-201113096049-A

Abstract:
a vascular filter stent is disclosed for deployment within a vessel for filtering of body fluids . a preferred embodiment is the placement of such vascular filter stent within the inferior vena cava to filter emboli for the prevention of pulmonary embolism . by incorporating a stent into the filter design , vessel patency and filter positioning is maintained , while minimizing endothelialization thereby obviating the long term complications of conventional metal vc filters such as filter migration and increased deep vein thrombosis .

Description:
embodiments of the present invention will now be described in detail with reference to the drawings , which are provided as illustrative examples so as to enable those skilled in the art to practice the invention . notably , the figures and examples below are not meant to limit the scope of the present invention to a single embodiment , but other embodiments are possible by way of interchange of some or all of the described or illustrated elements . wherever convenient , the same reference numbers will be used throughout the drawings to refer to same or like parts . where certain elements of these embodiments can be partially or fully implemented using known components , only those portions of such known components that are necessary for an understanding of the present invention will be described , and detailed descriptions of other portions of such known components will be omitted so as not to obscure the invention . in the present specification , an embodiment showing a singular component should not be considered limiting ; rather , the invention is intended to encompass other embodiments including a plurality of the same component , and vice - versa , unless explicitly stated otherwise herein . moreover , applicants do not intend for any term in the specification or claims to be ascribed an uncommon or special meaning unless explicitly set forth as such . further , the present invention encompasses present and future known equivalents to the components referred to herein by way of illustration . referring to the embodiment depicted in fig1 a , b , a vascular filter stent 1 consists of an outer , circumferential stent 2 for supporting a plurality of collapsible filter capture elements ( 30 - 34 ) and to maintain vessel patency . the capture elements are purposely designed to be collapsible for catheter - based installation and to avoid end organ damage . the supporting stent 2 is shown to be fabricated as an artificial vascular graft supported by undulating supporting structures 3 . collapsible capture elements can be fabricated with numerous materials . plausible materials include any suture such as surgical gut , vicryl ( polyglactin 910 ), monocryl ( poliglecaprone 25 ), pds ii ( polydioxanone ), silk , ethilon ( nylon ), nurolon ( nylon ), mersilene ( polyester fiber ), ethibond ( polyester fiber ), prolene ( polypropylene ), pronova poly ( hexafluoropropylene - vdf ), panacryl , orthocord , fiberwire , novafil ( polybutester ), vascufil ( polybutester ), surgipro ( polypropylene ), maxon ( polytrimethylene carbonate ), and dexon . as an alternative to assembling a plurality of capture elements , the vascular filter stent can be fabricated with composite mesh . candidates for a mesh capture system include polypropylene such as c - qur , polypropylene encapsulated by polydioxanone as in proceed , polypropylene co - knitted with polyglycolic acid fibers as in bard sepramesh ip composite , polyethylene terephathalate as in parietiex composite , and eptfe used in dualamesh . the circumferential stent element 2 in fig1 serves to support the capture elements of the vascular filter stent , in addition to maintaining vessel patency and maintaining stationary filter positioning within the vessel upon expansion . numerous types of stents conventionally employed as thoracic endoprostheses can be utilized . such stents would include gore tag , medtronic talent and valiant systems , and cook zenith tx2 system . in particular , the gore tag is comprised of an artificial vascular graft fabricated with a fluoropolymer ( expanded polytetrafluoroethylene eptfe and fluorinated ethylene propylene or fep ) combined with a nitinol supporting structure . alternatively , the stent component of the vascular filter stent can be fabricated with only the supporting structure ( without the artificial vascular graft ) utilizing nitinol , elgiloy , phynox , 316 stainless steel , mp35n alloy , titanium alloy , platinum alloy , niobium alloys , cobalt alloys , and tantalum wire . a preferred installation of the vascular filter stent is via intravenous insertion with a catheter requiring only a local anesthetic . much like deployment of a conventional thoracic endoprosthesis or stent , vascular filter stent is collapsed and compressed within a delivery catheter . for ivc deployment , the delivery catheter is inserted into the patient &# 39 ; s vasculature of convenient location , such as the femoral vein . subsequently , the delivery catheter is fed through the vasculature until reaching the desired deployment location , typically just inferior to the renal veins . next the compressed vascular filter stent is allowed to expand and subsequently the catheter housing is removed from the vein . consequently as a thrombosis event releases an embolus , the embolus is captured by the vascular filter stent and is prevented from traveling to the heart and lungs thereby preventing a potentially fatal pe . although the present invention has been described with reference to specific exemplary embodiments , it will be evident to one of ordinary skill in the art that various modifications and changes may be made to these embodiments without departing from the broader spirit and scope of the invention . accordingly , the specification and drawings are to be regarded in an illustrative rather than a restrictive sense . goldhaber s z , ortel t l . the surgeon general &# 39 ; 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