Abstract:
Disclosed is an assembly for filtering debris flowing in an in vivo fluid stream, the assembly comprising at least one balloon configured to volumetrically expand and, during at least a portion of the expansion, operatively connect with a filter, and to contract following the expansion. The assembly further comprising a filter configured to operatively connect with the at least one balloon during at least a portion of the volumetric expansion of the at least one balloon, such that the filter expands during the operative connection in order to filter debris from a fluid flowing in a fluid stream within which the expanded filter is disposed.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention relates generally to in vivo filters that filter debris from a fluid stream in which the filter is disposed. 
       BACKGROUND OF THE INVENTION 
       [0002]    In 1977 Andreas Gruntzig performed the first successful balloon angioplasty on an obstructed human artery, thereby opening the vessel and allowing improved flow of blood. 
         [0003]    Balloon angioplasty is a catheter-based procedure in which a long, thin tube with a deflated balloon at the tip is inserted into an artery. The balloon is guided to a stenotic lesion using X-ray fluoroscopy, rapidly inflated to a pressure of several atmospheres and deflated. Several rounds of inflation and deflation cause the stenotic lesion to crack and squash radially outward, thereby opening the obstructed lumen. 
         [0004]    Balloon Angioplasty may be indicated for improving circulation to virtually any stenosed organ vasculature or peripheral vasculature, including opening occluded vessels during an acute heart attack; and in place of surgical endarterectomy, treatment of carotid artery stenosis, in high-risk surgical patients. 
         [0005]    A problem associated with balloon angioplasty is that the stenotic lesion may release debris that travels to vital organs, for example the brain and/or lungs, causing vascular blockage, tissue necrosis and/or patient death. 
         [0006]    To prevent such draconian sequela, a number of in vivo debris filter devices have been developed that are designed to capture debris released from stenotic lesions during an angioplasty procedure. 
         [0007]    Using a guide passage, such a debris filter is positioned downstream of the intended angioplasty site and expanded to press against the tissue surrounding the lumen, thereby effectively filtering all blood passing through the lumen. A balloon angioplasty catheter is then introduced into the artery and the balloon is positioned adjacent the stenotic lesion. The balloon is inflated, the lesion releases debris and the filter captures the debris. After deflation and removal of the balloon, the filter is contracted and removed with the captured debris. 
         [0008]    The use of in vivo debris filters during balloon angioplasty, however, may fail to prevent vascular blockage, tissue necrosis and/or patient death. To be effective, in vivo debris filters are positioned quite a distance downstream from the lesion undergoing angioplasty; considerably raising the chances that a vessel branching off the treated vessel will be located between the angioplasty balloon and the filter. Debris generated by the angioplasty will likely find its way into the branch vessel and travel to the lungs or brain, causing the above-noted sequela. 
         [0009]    Additionally the filter itself may pose a health hazard to the patient. The deployment zone for the filter often comprises healthy vascular tissue. Positional adjustments and expansion of the filter against the healthy vascular tissue can cause tissue scars and plaques that, of themselves, provide a breeding ground for additional, full-blown, stenotic lesions. 
         [0010]    In spite of the above-noted risk and health hazard, use of a debris filter is indicated for patients having “rupture-prone” lesions; stenotic lesions characterized by thin fibrous caps and large lipid cores. Even though it is impossible to introduce a filter once the balloon angioplasty has begun, in theory, pre-operative identification of a rupture-prone stenotic lesion would allow the patient and surgeon to weigh the risks and benefits of using an in vivo debris filter in addition to the angioplasty balloon catheter. 
         [0011]    Unfortunately, the above theoretical solution is almost totally unworkable in practice because the very lesions that are rupture-prone are often not visible by x-ray angiography. 
         [0012]    (Z. A. Fayad et al: “Clinical Imaging of the High-Risk or Vulnerable Atherosclerotic Plaque”;  Circulation Research.  2001; 89: 305.) 
         [0013]    The surgeon and patient, therefore, are left to grope in the dark for answers as to whether to risk patient health and deploy a debris filter. 
         [0014]    In general, existing devices and technology present a number of additional disadvantages associated with the stand-alone in vivo debris filter, including:
       1) the additional thousands of dollars to pay for each disposable filter for each surgery;   2) the difficulty in surgically deploying the filter in addition to a balloon angioplasty; and   3) the additional surgical fee charged by the surgeon for performing a second surgical procedure associated with the filter.       
 
       SUMMARY OF THE INVENTION 
       [0018]    Some embodiments of the present invention successfully address at least some of the shortcomings of the prior art by providing an assembly for filtering debris flowing in an in vivo fluid stream, the assembly comprises a balloon configured to volumetrically expand and, during at least a portion of the expansion, operatively connect with a filter, thereby expanding the filter. 
         [0019]    There is thus provided an assembly for filtering debris flowing in an in vivo fluid stream, the assembly comprising at least one balloon configured to volumetrically expand and, during at least a portion of the expansion, operatively connect with a filter, and to contract following the expansion. The assembly further comprising a filter configured to operatively connect with the at least one balloon during at least a portion of the volumetric expansion of the at least one balloon, such that the filter expands during the operative connection in order to filter debris from a fluid flowing in a fluid stream within which the expanded filter is disposed. 
         [0020]    In embodiments, the at least one balloon comprises at least one proximal portion and at least one distal portion. In embodiments, and the operative connection between the at least one balloon and the filter occurs in the at least one proximal portion. In embodiments, the operative connection between the at least one balloon and the filter occurs in the at least one distal portion. 
         [0021]    In embodiments, a maximal expansion diameter of the at least one distal portion is greater than a maximal expansion diameter of the at least one proximal portion. In embodiments, a maximal expansion diameter of the at least one proximal portion is greater than a maximal expansion diameter of the at least one distal portion. 
         [0022]    In embodiments, the at least one balloon comprises at least one angioplasty balloon. In embodiments, the at least one balloon comprises at least two balloons, at least one first balloon and at least one second balloon. 
         [0023]    In embodiments, the at least one first balloon is positioned proximally to the at least one second balloon. In embodiments, the at least one first balloon has a first maximal inflation diameter and the at least one second balloon has a second maximal inflation diameter. 
         [0024]    In embodiments, at least a portion of the filter is configured to removably connect to a luminal aspect associated with the fluid stream, in response to pressure by the at least one balloon of between at least about one atmosphere and no more than about 20 atmospheres. 
         [0025]    In embodiments, at least a portion of the filter is configured to remain removably connected to the luminal aspect during the contraction of the at least one balloon. In embodiments, the at least one balloon is configured to sequentially pass through at least two sequences of the expansion and contraction of the at least one balloon. 
         [0026]    In embodiments, at least a portion of the filter is configured to remain removably connected to a luminal aspect associated with the fluid stream during at least a portion of the at least two sequences. 
         [0027]    In embodiments, the assembly includes at least one cord operatively associated with the filter and configured to disconnect at least a portion of the filter from the luminal aspect when tension is applied to the at least one cord. 
         [0028]    In embodiments, at least a portion of the filter is configured to disconnect from the luminal aspect in response to tension applied to the at least one cord of at least about one Newton. 
         [0029]    In embodiments, at least a portion of the filter is configured to disconnect from the luminal aspect in response to tension applied to the at least one cord of no more than about 20 Newtons. 
         [0030]    In embodiments, at least a portion of the filter includes a pressure-sensitive adhesive having an affinity for a tissue associated with an in vivo luminal aspect. 
         [0031]    In embodiments, the adhesive is an adhesive from the group of adhesives comprising fibrin, biological glue, collagen, hydrogel, hydrocolloid, collagen alginate, and methylcellulose. 
         [0032]    In embodiments, at least a portion of the filter is configured to removably connect to a luminal aspect associated with the fluid stream, in response to pressure by the at least one balloon of between at least about one atmosphere and no more than about 20 atmospheres. 
         [0033]    In embodiments, at least a portion of the filter is configured to remain removably connected to the luminal aspect during the contraction of the at least one balloon. 
         [0034]    In embodiments, the at least one balloon is configured to sequentially pass through at least two sequences of the expansion and contraction of the at least one balloon. 
         [0035]    In embodiments, at least a portion of the filter is configured to remain removably connected to the luminal aspect during at least a portion the at least two sequences. 
         [0036]    In embodiments, the assembly includes at least one cord operatively associated with the filter and configured to disconnect at least a portion of the filter from the luminal aspect when tension is applied to the at least one cord. 
         [0037]    In embodiments, at least a portion of the filter is configured to disconnect from the luminal aspect in response to tension applied to the at least one cord of at least about one Newton. 
         [0038]    In embodiments, at least a portion of the filter is configured to disconnect from the luminal aspect in response to tension applied to the at least one cord of no more than about 20 Newtons. 
         [0039]    In embodiments, the assembly includes a compression sleeve comprising a substantially curved wall having a proximal end, a distal end and a lumen extending from the proximal end to the distal end, the lumen having a cross sectional diameter that is substantially smaller than the maximal cross sectional diameter of the luminal aspect and at least one cord operatively associated with the filter, at least a portion of the at least one cord slidingly juxtaposed within the compression sleeve lumen, such that in response to at least one first distal sliding of the sleeve while the at least one cord is held stationary, the filter is caused to disconnect from the luminal aspect. 
         [0040]    In embodiments, in response to at least one second distal sliding of the sleeve while the at least one cord is held stationary, the filter is caused to radially contract such that a maximal cross sectional diameter of the filter is smaller that a cross sectional diameter of the sleeve lumen. 
         [0041]    In embodiments, in response to at least one third distal sliding of the sleeve while the at least one cord is held stationary; at least a portion of the filter is caused to enter the sleeve lumen. 
         [0042]    In embodiments, the at least one balloon comprises an outer wall having a distal end and a proximal end and an inner wall defining a lumen, the lumen extending from the distal end to the proximal end, and 
         [0043]    In embodiments, at least a portion of the at least one cord is configured to slidingly pass through the lumen. 
         [0044]    In embodiments, the at least one cord is configured to pull at least a portion of the filter into contact with the distal end of the at least one balloon. 
         [0045]    In embodiments, the assembly includes a catheter having a distal end and a proximal end and a lumen extending from the distal end to the proximal end, wherein the at least one balloon proximal end is operatively associated with the distal end of the catheter. 
         [0046]    In embodiments, the at least one balloon lumen is substantially continuous with the catheter lumen. 
         [0047]    In embodiments, at least a portion of the at least one cord additionally extends through the catheter lumen. 
         [0048]    In embodiments, the filter includes a distal portion, a proximal portion, an opening to the filter associated with the proximal portion and at least one strut operatively associated with the proximal portion. 
         [0049]    In embodiments, the assembly includes at least one cord operatively associated with the at least one strut, such that at least a portion of the opening is configured to contract radially inwardly in response to tension applied to the at least one cord. 
         [0050]    In embodiments, the at least one strut comprises at least two struts operatively associated with the at least one cord. 
         [0051]    In embodiments, each of the at least two struts is configured to resiliently flex outward to form at least one expanded cross sectional diameter. 
         [0052]    In embodiments, the at least one expanded cross sectional diameter defines at least two sections, a first section having a first radius and a second section having a second radius. 
         [0053]    In embodiments, the at least one strut comprises at least six struts operatively associated with the at least one cord. 
         [0054]    In embodiments, the at least one cord comprises at least two cords and the at least one strut comprises at least two struts. 
         [0055]    In embodiments, the at least one cord comprises at least six cords and the at least one strut comprises at least six struts. 
         [0056]    In embodiments, the at least one balloon includes an inflation channel in fluid communication with an interior portion of the at least one balloon, wherein the channel is configured to inflate the at least a portion of the at least one balloon by introduction of a fluid through the inflation channel. 
         [0057]    In embodiments, the assembly includes a catheter comprising a curved wall extending proximally from the at least one balloon and the inflation channel comprises a curved wall surrounding at least a portion of the catheter. 
         [0058]    In embodiments, the at least one balloon comprises a material from the group consisting of: rubber, silicon rubber, latex rubber, polyethylene, polyethylene terephthalate, and polyvinyl chloride. 
         [0059]    In embodiments, the filter includes a distal portion, a proximal portion, an opening to the filter associated with the proximal portion, and at least one cord guide channel circumferentially encircling at least a portion the proximal portion. 
         [0060]    In embodiments, the assembly includes at least one cord, at least a portion of the at least one cord passes through the guide channel, such that at least a portion of the opening is configured to contract radially inwardly in response to tension applied to the at least one cord. 
         [0061]    In embodiments, the filter comprises a flexible sheet material and the guide channel is formed from at least one of a bending of a portion of the sheet material, and a shaped component attached to the sheet material. 
         [0062]    In embodiments, the at least one cord channel comprises at least two cord channels located substantially on the same cross sectional plane of the filter and the at least one cord comprises at least two cords. 
         [0063]    An assembly for filtering debris flowing in an in vivo fluid stream, the assembly comprising at least one balloon configured to volumetrically expand and, during at least a portion of the expansion, operatively connect with a filter, and to contract following the expansion, and a filter comprising a material having tissue connective properties for a tissue associated with an in vivo fluid stream, the filter positioned to operatively connect with the at least one balloon and removably connect to least a portion of the tissue and remain so connected during the contractions of the at least one balloon. 
         [0064]    In embodiments, the at least one balloon comprises at least one proximal portion and at least one distal portion. In embodiments, and the operative connection between the at least one balloon and the filter occurs in the at least one proximal portion. 
         [0065]    In embodiments, the operative connection between the at least one balloon and the filter occurs in the distal portion. 
         [0066]    In embodiments, a maximal expansion diameter of the at least one distal portion is greater than a maximal expansion diameter of the at least one proximal portion. 
         [0067]    In embodiments, a maximal expansion diameter of the at least one proximal portion is greater than a maximal expansion diameter of the at least one distal portion. 
         [0068]    In embodiments, the at least one balloon comprises at least one angioplasty balloon. In embodiments, the at least one balloon comprises at least two balloons, at least one first balloon and at least one second balloon. 
         [0069]    In embodiments, the at least one first balloon is positioned distally to the at least one second balloon. In embodiments, the at least one first balloon has a first maximal inflation diameter that a maximal inflation diameter of the second balloon. 
         [0070]    In embodiments, at least a portion of the filter is configured to removably connect to a luminal aspect associated with the fluid stream, in response to pressure by the at least one balloon of between at least about one atmosphere and no more than about 20 atmospheres. 
         [0071]    In embodiments, the at least one balloon is configured to sequentially pass through at least two sequences of the expansion and contraction of the at least one balloon. In embodiments, at least a portion of the filter is configured to remain removably connected to a luminal aspect associated with the fluid stream during at least a portion of the at least two sequences. 
         [0072]    In embodiments, the assembly includes at least one cord operatively associated with the filter and configured to disconnect at least a portion of the filter from a luminal aspect associated with the fluid stream when tension is applied to the at least one cord. 
         [0073]    In embodiments, at least a portion of the filter is configured to disconnect from a luminal aspect associated with the fluid stream when the applied tension to the at least one cord is between at least about one Newton and no more than about 20 Newtons. 
         [0074]    In embodiments, at least a portion of the filter includes a pressure-sensitive adhesive having an affinity for a tissue associated with an in vivo luminal aspect. In embodiments, the adhesive is an adhesive from the group of adhesives comprising fibrin, biological glue, collagen, hydrogel, hydrocolloid, collagen alginate, and methylcellulose. 
         [0075]    In embodiments, at least a portion of the filter is configured to removably connect to a luminal aspect associated with the fluid stream, in response to pressure by the at least one balloon of between at least about one atmosphere and no more than about 20 atmospheres. 
         [0076]    In embodiments, the at least one balloon is configured to contract following the expansion and at least a portion of the filter is configured to remain removably connected to the luminal aspect during the at least one balloon contraction. 
         [0077]    In embodiments, the at least one balloon is configured to sequentially pass through at least two sequences of the expansion and contraction of the at least one balloon. 
         [0078]    In embodiments, at least a portion of the filter is configured to remain removably connected to the luminal aspect during at least a portion the at least two sequences. 
         [0079]    In embodiments, the assembly includes at least one cord operatively associated with the filter and configured to disconnect at least a portion of the filter from the luminal aspect when tension is applied to the at least one cord. In embodiments, at least a portion of the filter is configured to disconnect from the luminal aspect in response to tension applied to the at least one cord of between at least about one Newton and no more than about 20 Newtons. 
         [0080]    There is thus provided a method for collecting debris from a stenotic lesion associated with a primary stenotic vessel while preventing passage of the debris into a branch vessel branching from the primary vessel, the method comprising detecting the stenotic lesion in the primary stenotic vessel, locating a filter in the primary stenotic vessel such that an opening of the filter is distal to a center of the stenotic lesion, locating at least a proximal portion an angioplasty balloon proximal to the opening in the filter, expanding the angioplasty balloon, contacting the opening of the filter with at least a distal portion of the angioplasty balloon during the expanding, causing the filter to open during the contacting, generating debris from the stenotic lesion by the expanding of the angioplasty balloon, capturing the debris in the filter, preventing passage of the debris into the branch vessel by the contacting of the opening of the filter with the at least a distal portion of the angioplasty balloon, contracting disengaging the angioplasty balloon, and removing the angioplasty balloon from the primary stenotic vessel. 
         [0081]    In embodiments, the method further comprises contracting the filter. In embodiments, the method further comprises removing the filter from the primary stenotic vessel. 
         [0082]    There is thus provided a method for collecting debris within a blood vessel, the method comprising juxtaposing an opening of an in vivo debris filter with at least one balloon, expanding the at least one balloon in a blood vessel, opening the filter during the expansion of the at least one balloon, collecting debris within the filter, disengaging the at least one balloon from the filter, and removing the at least one balloon from the vessel. 
         [0083]    In embodiments, the method further comprises contracting the filter, and removing the filter from the blood vessel. In embodiments, the method further comprises contacting a stenotic vascular lesion during the expanding. 
         [0084]    In embodiments, the method further comprises compressing the lesion during the expanding. In embodiments the method further comprises releasing debris from the lesion during the compressing. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0085]    The invention for safely collecting debris using a debris filter positioned in assembly with an angioplasty balloon is described by way of example with reference to the accompanying drawings. With specific reference now to the drawings in detail, it is stressed that the particulars shown are by way of example and for purposes of illustrative discussion of the preferred method of the present invention only, and are presented in the cause of providing what is believed to be the most useful and readily understood description of the principles and conceptual aspects of the invention. In this regard, no attempt is made to show structural details of the invention in more detail than is necessary for a fundamental understanding of the invention, the description taken with the drawings making apparent to those skilled in the art how the methods of the invention may be embodied in practice. 
           [0086]      FIG. 1   a - 1   d  show deployment of an in vivo filter and balloon assembly in a vessel shown in cross section, according to an embodiment of the invention; and 
           [0087]      FIGS. 2   a - 2   d,    3   a - 3   c,    4 , and  5   a - 5   e  show alternative embodiments of the filter and balloon assembly shown in  FIGS. 1   a - 1   d,  according to the invention. 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0088]    The present invention relates to an in vivo filter that is biased to an open position in conjunction with inflation of an angioplasty balloon. In an exemplary embodiment, during balloon inflation against a stenotic lesion, the balloon presses the outer surface of the filter into a luminal aspect directly upstream from the lesion to capture stenotic debris. The filter maintains thus positioned throughout multiple angioplasty inflations and deflations, following which cords are used to remove the filter from the lumen. 
         [0089]    The principles and uses of the teachings of the present invention may be better understood with reference to the accompanying description, Figures and examples. In the Figures, like reference numerals refer to like parts throughout. 
         [0090]    Before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details set forth herein. The invention can be implemented with other embodiments, and can be practiced or carried out in various ways. 
         [0091]    It is also understood that the phraseology and terminology employed herein is for descriptive purpose and should not be regarded as limiting. 
         [0092]    Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the invention belongs. In addition, the descriptions, materials, methods, and examples are illustrative only and not intended to be limiting. Methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention. 
         [0093]    As used herein, the terms “comprising” and “including” or grammatical variants thereof are to be taken as specifying the stated features, integers, steps or components but do not preclude the addition of one or more additional features, integers, steps, components or groups thereof. This term encompasses the terms “consisting of” and “consisting essentially of”. 
         [0094]    As used herein, “a” or “an” mean “at least one” or “one or more”. The use of the phrase “one or more” herein does not alter this intended meaning of “a” or “an”. 
       Filter Assembly  100   
       [0095]      FIG. 1   a  shows an exemplary representation of an in vivo debris filter assembly  100  of the present invention, in a cross section of a blood vessel  141 . A filter  122  is shown in a contracted, pre-dilated, position with loose cords  110  attached to two struts  128  that are connected to filter  122 . Cords  110  exit filter  122  and pass through a lumen  138  and into and through a catheter  132 . Cords  110  typically exit lumen  138  ex vivo, thereby allowing ex vivo manipulation by an operator. 
         [0096]    A balloon  130  projects downstream of catheter  132  and is positioned adjacent a stenotic lesion  144 . Balloon  130  typically comprises a biologically compatible elastomeric material, or semi compliance material, for example: rubber, silicon rubber, latex rubber, polyethylene, polyethylene terephthalate, Mylar, and/or polyvinyl chloride. 
         [0097]    In  FIG. 1   b,  balloon  130  has been inflated by introducing fluid through a fluid channel  148  that is substantially coaxial to catheter  130 . During inflation of balloon  130 , after the diameter of balloon  130  reaches the distance between struts  128 , continued inflation of balloon  130  causes struts  128  to bias radially outwardly, thereby expanding filter  122 . 
         [0098]    Once inflated, filter  122  filters debris  160  that is released from stenotic lesion  144  and continues to filter debris  160  even as balloon  130  is deflated, as explained below. 
         [0099]    While filter  122  is shown in an expanded position as a generally curved structure, balloon  130  may alternatively have a variety of shapes, including a conus having an apex located downstream of balloon  130 . 
         [0100]    Filter  122  typically comprises a mesh sheet material that is configured to filter debris  160  from a lumen  142 . Filter  122  typically includes apertures having diameters of between at least about 20 microns and no more than about 200 microns in diameter. 
         [0101]    Additionally, filter  122  and/or struts  128 , are configured to flex outward until such flexion is limited by a luminal aspect  140 , for example a diameter of between 3.0 and 6.0 millimeters, depending on the size of lumen  142  in which filter  122  is deployed. 
         [0102]    In further embodiments, portions of filter  122  and/or struts  128  comprise super elastic material, for example nitinol; an elastic material; and/or a plastic material; the many materials and their properties being well-known to those familiar with the art. 
         [0103]    Similarly balloon  130  has an inflation diameter of between 3.0 and 6.0 millimeters, depending on the cross sectional diameter of lumen  142 . In larger vessels  141 , balloon  130  and filter  122  optionally are manufactured to have larger maximal diameters. In smaller vessels, for example to cut down on the bulk of deflated balloon  130  and filter  122 , smaller maximal diameters are optionally appropriate. 
         [0104]    Filter  122  comprises materials and/or apertures that aid in removably connecting filter  122  to an in vivo luminal aspect  140 . In this manner, filter  122  remains connected to luminal aspect  140  for a period of time after balloon  130  has deflated, herein contracted, by egress of fluid through channel  148 . By remaining in contact with luminal aspect  140 , filter  122  continues to filter debris  160  that may be released into lumen  142  from lesion  144  while balloon  130  is in a contracted state. 
         [0105]    In some embodiments, the material and configuration of filter  122  ensures that filter  122  remains removably connected to luminal aspect  140  following deflation of balloon  130 . In other embodiments, filter  122  includes a pressure sensitive adhesive having an affinity for luminal aspect  140  so that the adhesive, optionally in conjunction with the material of filter  130 , remain removably connect to vessel luminal aspect  140  following deflation of balloon  130 . 
         [0106]    There are many adhesives that may be contemplated for use in providing a removable connection of filter  122  to luminal aspect  140  including, inter alia: fibrin, biological glue, collagen, hydrogel, hydrocolloid, collagen alginate, and methylcellulose, to name a few. 
         [0107]    Whether filter  122  comprises a mesh material alone or in combination with an adhesive, filter  122  is optionally configured to removably connect to luminal aspect  140  from a pressure exerted by balloon  130  of, for example, between one and twenty atmospheres. 
         [0108]    In further exemplary embodiments, for example when there is continued danger of debris  160  being generated after lesion  144  has been compressed, balloon  130  is optionally deflated and removed from lumen  142  while filter  122  is left in place. Filter  122  optionally is left connected to luminal aspect  140  by the configuration of filter  122  and/or biological glues noted above until the danger of generation of debris  160  has passed. 
         [0109]    As noted above, during a typical balloon angioplasty, balloon  130  is sequentially inflated to a pressure of several atmospheres and deflated. In exemplary embodiments, filter  122  remains removably connected to luminal aspect  140  following the first inflation of balloon  130  and throughout several sequences of inflation and deflation. 
         [0110]    As filter  122  is deployed relatively proximate to lesion  144  where luminal aspect  140  generally comprises unhealthy tissue, the chance that filter  122  will cause damage to healthy tissue of luminal aspect  140  is very low. 
         [0111]    Additionally, the proximity of filter  122  to balloon  130  substantially lowers the odds that a branch artery will be located between filter  122  and balloon  130 , to act as a conduit for debris  160 . Further, as balloon  130  and filter  122  are deployed on single catheter  132 , the cost for each assembly  100  should be lower than existing technology employing a separate filter. Moreover, as assembly  100  includes balloon  130  and filter  122  mounted on a single catheter, the complexity of manufacture, deployment and the surgical fees to the surgeon should be reduced over existing technology. 
         [0112]    As seen in  FIG. 1   c,  after stenotic lesion  144  has been cracked and squashed radially outwards, balloon  130  is deflated and filter  122  remains in an expanded state and continues to capture debris  160 . As the fluid contained in lumen  142  is moving in a direction  162 , in a distal or downstream direction with respect to filter  122 , debris  160  remains in place, captured within filter  122 . 
         [0113]    As used herein, the terms distal and distally refer to a position and a movement, respectively, in downstream direction  162 . 
         [0114]    To disconnect filter  122  from luminal aspect  140 , cords  110  are pulled proximally, upstream, in a direction  164 . As used herein, the terms proximal and proximally refer to a position and a movement, respectively, in upstream direction  164 . 
         [0115]    While cords  110 , as shown, pass through catheter lumen  138 , in alternative embodiments, cords  110  pass to the side of balloon  130  without passing through a lumen  138 . Further, while balloon  130  is shown attached to catheter,  132 , there are many alternative options for delivering balloon  130  and filter  122 , for example using a guide wire. Those familiar with the art will readily recognize the many alternative modes and configurations available for delivery and operation of balloon  130  and filter  122 . 
         [0116]    In an exemplary embodiment, filter  122  is configured to disconnect from luminal aspect  140  in response to tension applied to cords  110  of at least about one Newton and no more than about 20 Newtons. 
         [0117]    As the diameter of lumen  142  is larger than the diameter of catheter lumen  138 , continued upstream pull in direction  164  on cords  110 , biases the proximal portions of struts  128  radially inward, causing the proximal edges of filter  122  to move radially inward so that filter  122  disconnects from luminal aspect  140 . Following disconnection of filter  122  from luminal aspect  140 , continued pulling of cords  110  in direction  164  causes struts  128  to inwardly bias, thereby reducing the upstream cross sectional diameter of filter  122 . 
         [0118]    As the fluid in lumen  142  travels distally in direction  162 , pulling catheter  132  and filter  122  in proximal direction  164  causes debris  160  to move downstream against filter  122  so that debris  160  remains captured by filter  122 . 
         [0119]    Thus, filter  122  maintains captured debris  160  even when there is a distance between struts  128 , as might occur when there is considerable volume of debris  160 , for example in large arteries. Optionally, cords  110  are pulled in direction  164  until a portion of filter  122  contacts balloon  130  and/or enters catheter lumen  138 . 
         [0120]    While two struts  128  are shown connected to two cords  110 , the present embodiments, contemplate four or even eight struts  128 , with each strut  128 , or each pair of struts  128 , being attached to individual cords  110  that remove filter  122  from luminal aspect  140 . 
         [0121]    Alternatively, assembly  100  contemplates using a single strut  128  with a single cord  110  connected to single strut  128  that encircles filter  122  and slidingly attaches to strut  128  in a lasso configuration. Pulling on single cord  110  causes contraction of struts  128  and of the associated cross-sectional circumference of filter  122 , thereby preventing egress of debris  160  filter  122 . The many options available for configuring cords  110  and struts  128  to effectively close filter  122  are well known to those familiar with the art. 
       Filter Assembly  200   
       [0122]      FIG. 2   a  shows an exemplary embodiment of an assembly  200  in which a single cord  112  passes distally in direction  162  through catheter lumen  138 . Cord  112  then curves within filter  122  to pass in a proximal direction  164  into a cord inlet  184  and through a cord channel  120 . Cord channel  120  guides cord  112  circumferentially around filter  122 . After circling filter  122 , cord  112  exits channel  120  through cord outlet  186  and passes distally in direction  162  into filter  122 . Cord  112  then curves within filter  122  to pass in a proximal direction  164  into and through catheter lumen  138 . 
         [0123]    In this manner both ends of cord  112  exit catheter lumen  138  and, by pulling both ex vivo ends of cord  112  in direction  164 , filter  122  is contracted along channel  120 , as seen in  FIG. 2   d.  While a single cord  112  is shown, channel  120  optionally comprises multiple pairs of inlets  184  and outlets  186 , each associated with a separate cord  112 . The many configurations and modifications of channel  120 , inlet  184 , and outlet  186  are well known to those familiar with the art. 
         [0124]      FIG. 2   d  shows an exemplary embodiment of a tubular compression sleeve  134  that is coaxial with catheter  132 . Sleeve  134  has been slidingly pushed through vessel lumen  142  in direction  162  until sleeve  134  approaches filter  122 . 
         [0125]    In an exemplary embodiment, pulling cord  112  and/or catheter  132  in direction  164  while holding sleeve  134  substantially stationary pulls filter  122  into compression sleeve  134 . Alternatively, compression sleeve  134  is advanced in direction  162  while catheter  132  and/or cord  110  are held substantially stationary. 
         [0126]    In an exemplary embodiment, compression sleeve  134  serves as a housing for filter  122  to prevent filter  122  from scraping along luminal aspect  140  during removal from lumen  142 . Additionally or alternatively, compression sleeve  134  serves to compress filter  122  into a smaller maximal circumferential diameter so that filter  122  more easily passes through lumen  142  during removal of filter  122 . 
       Balloon Assembly  300   
       [0127]    In embodiments, balloon  130  optionally includes alternative shapes, for example having varied cross sectional diameters. As seen in assembly  300  ( FIG. 3   a ), the diameter associated with a distal portion  133  of deflated balloon  130  is larger than the diameter associated with a proximal portion  139 . 
         [0128]    As seen in  FIG. 3   b,  filter  122  reaches a maximal diameter initially as distal balloon portion  133  inflates. In this manner, filter  122  is fully in position and expanded prior to inflation of proximal balloon portion  139 . 
         [0129]    As seen in  FIG. 3   c,  proximal balloon portion  139  has been fully inflated to compress lesion  144 , thereby releasing debris  160  that is captured by filter  122 . The many options for configuring alternative shapes of balloon  130  are well known to those familiar with the art. 
       Balloon and Filter Assembly  400   
       [0130]    There are additionally many methods of assembling filter  122  and balloon  130 , as seen in assembly  400  ( FIG. 4 ). In a non-limiting embodiment, balloon  130  is seen having an overall length  209  of approximately 38 millimeters and a maximal inflation diameter  211  of approximately 5 millimeters. 
         [0131]    Additionally, balloon  130  is shown with a proximal portion  207  having a length  235  of approximately 18 millimeters and a distal portion  208  having a length  233  of approximately 18 millimeters. 
         [0132]    In an exemplary embodiment, filter  122  extends to substantially cover distal portion  208  while proximal portion  207  is unprotected by filter  122 . 
         [0133]    In alternative configurations of assembly  400 , filter  122  optionally substantially fully covers distal balloon portion  208  and extends over at least a portion of proximal balloon portion  207 ; the many configurations of assembly  400  being well known to those familiar with the art. 
       Dual Balloon Assembly  500   
       [0134]    Assembly  500  ( FIGS. 5   a - 5   e ) demonstrates just one more of the many embodiments of the instant invention that are easily contemplated by those familiar with the art. Assembly  500  comprises a proximal balloon  230  and a distal balloon  101 . As seen in  FIG. 5   b,  distal balloon  101  is inflated to expand filter  122  and substantially take up the volume within filter  122 . As seen in  FIG. 5   c,  proximal balloon  230  is inflated separately and pressed against lesion  144 . 
         [0135]    After deflation of proximal balloon  230  as seen in  FIG. 5   d,  distal balloon  101  remains inflated so that debris  160  remains proximal to distal balloon  101 . Upon deflation of distal balloon  101 , debris  160  enters and is captured by filter  122 . 
       Alternative Environments 
       [0136]    While assemblies  100 - 500  have been described with respect to vessel  141 , assemblies  100 - 500  can be easily configured for use in a wide variety of in vivo lumens  142  including inter alia: a lumen of a urethra, a biliary lumen and/or a renal calyx lumen. Additionally or alternatively, filter  122  can be easily modified to capture debris in virtually any in vivo lumen  142  including, inter alia: biliary stones and/or renal stones. The many applications, modifications and configurations of assemblies.  100 - 500  for use in virtually any in vivo lumen  142  will be readily apparent to those familiar with the art. 
       Materials and Design 
       [0137]    In embodiments, filter  122  comprises a sheet material configured to extend distally with respect to balloon  130  while filter  122  is expanded. In embodiments, the sheet material of filter  122  is selected from the group consisting of: meshes and nets. 
         [0138]    In embodiments, bending of a portion of the sheet material of filter  122  forms filter cord channel  120 . In embodiments, attaching a shaped component to filter  122  forms filter cord channel  120 . 
         [0139]    In embodiments, the material of filter  122  has a thickness of at least about 20 microns. In embodiments, the material of filter  122  has a thickness of no more than about 200 microns. In embodiments, the material of filter  122  includes apertures having diameters of at least about 20 microns. In embodiments, the material of filter  122  includes apertures having diameters of no more than about 80 microns in diameter. In embodiments, the material of filter  122  is manufactured using a technique from the group of techniques consisting of: interlacing, knitting, weaving, braiding, knotting, wrapping, and electro spinning. 
         [0140]    In embodiments, filter  122  is configured to expand to a cross sectional diameter of at least about 1.0 millimeters. In embodiments, filter  122  is configured to expand to a cross sectional diameter of no more than about 6.0 millimeters. In embodiments, the extent of the expansion of filter  122  is configured to be limited by the walls of luminal aspect  140  in which filter  122  is deployed. 
         [0141]    In embodiments, balloon  130  has a maximum inflation diameter of at least about 1.0 millimeter. In embodiments, balloon  130  has a maximum inflation diameter of no more than about 6.0 millimeters. 
         [0142]    In embodiments, balloon  130  has a wall thickness of at least about 0.2 millimeters. In embodiments, balloon  130  has a wall thickness of no more than about 0.5 millimeters. 
         [0143]    In embodiments, strut  128  has a substantially circular cross section having a diameter of at least about 0.1 millimeters. In embodiments, strut  128  has a substantially circular cross section having a diameter of no more than about 0.6 millimeters. 
         [0144]    In embodiments, strut  128  has a cross section having greater and lesser measurements and the greater measurement is at least about 0.1 millimeters. In embodiments, strut  128  has a cross section having greater and lesser measurements and the greater measurement is no more than about 0.6 millimeters. In embodiments, strut  128  has a cross section having greater and lesser measurements and the lesser measurement is at least about 0.1 millimeters. In embodiments, strut  128  has a cross section having greater and lesser measurements and the lesser measurement is no more than about 0.6 millimeters. 
         [0145]    In embodiments, filter  122  has an internal and an external aspect and strut  128  is attached to the internal aspect or the external aspect of filter  122 . In embodiments, strut  128  is attached to filter  122  using a process selected from the group consisting of: sewing, adhesion, gluing, suturing, riveting and welding. 
         [0146]    In embodiments, cord channel  120  comprises at least two cord channels; and cord  112  comprises at least two cords. 
         [0147]    In embodiments, catheter  132  has an outside diameter of at least about 1.0 millimeter. In embodiments, catheter  132  has an outside diameter of no more than about 5.0 millimeters. In embodiments, catheter  132  has a length of at least about 0.8 meter. In embodiments, catheter  132  has a length of no more than about 1.5 meters. 
         [0148]    In embodiments, the walls of catheter  132  compression sleeve  134  have a thickness of at least about 2 millimeters. In embodiments, the walls of catheter  132  compression sleeve  134  have a thickness of more than about 5 millimeters. 
         [0149]    In embodiments, filter  122 , cord  110  ( FIG. 1   a ) and cord  112  ( FIG. 2   a ), strut  128 , compression sleeve  134 , and catheter  132 , comprise a material from the group consisting of: polyethylene, polyvinyl chloride, polyurethane and nylon. 
         [0150]    In embodiments, filter  122 , cord  110  ( FIG. 1   a ) and cord  112  ( FIG. 2   a ), strut  128 , compression sleeve  134 , and catheter  132 , comprise a material selected from the group consisting of: nitinol, stainless steel shape memory materials, metals, synthetic biostable polymer, a natural polymer, and an inorganic material. In embodiments, the biostable polymer comprises a material from the group consisting of: a polyolefin, a polyurethane, a fluorinated polyolefin, a chlorinated polyolefin, a polyamide, an acrylate polymer, an acrylamide polymer, a vinyl polymer, a polyacetal, a polycarbonate, a polyether, an aromatic polyester, a polyether (ether keto), a polysulfone, a silicone rubber, a thermoset, and a polyester (ester imide). 
         [0151]    In embodiments the natural polymer comprises a material from the group consisting of: a polyolefin, a polyurethane, a Mylar, a silicone, a polyester and a fluorinated polyolefin. 
         [0152]    In embodiments, filter  122 , cord  110  ( FIG. 1   a ) and cord  112  ( FIG. 2   a ), strut  128 , compression sleeve  134 , and catheter  132 , comprise a material having a property selected from the group consisting of: compliant, flexible, plastic, and rigid. 
         [0153]    It is appreciated that certain features of the invention, which are, for clarity, described in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the invention, which are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable subcombination. 
         [0154]    Although the invention has been described in conjunction with specific embodiments thereof, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art. 
         [0155]    Accordingly, the invention is intended to embrace all such alternatives, modifications and variations that fall within the spirit and broad scope of the appended claims. All publications, patents and patent applications mentioned in this specification are herein incorporated in their entirety by reference into the specification, to the same extent as if each individual publication, patent or patent application was specifically and individually indicated to be incorporated herein by reference. In addition, citation or identification of any reference in this application shall not be construed as an admission that such reference is available as prior art to the present invention.