Abstract:
Disclosed is a method of preventing atrial appendage thrombus from entering the blood stream in which an occlusion device placed within the left atrial appendage inhibits compression of the left atrial appendage and facilitates tissue in-growth onto the occlusion member. The occlusion device includes an occlusion member, a plurality of supports and a plurality of barbs associated with the plurality of supports.

Description:
This is a continuation of U.S. patent application Ser. No. 13/109,898, filed May 17, 2011, now U.S. Pat. No. 8,535,343, which is a continuation of U.S. patent application Ser. No. 10/830,964, filed Apr. 22, 2004, now abandoned, which is a continuation of U.S. patent application Ser. No. 09/435,562, filed Nov. 8, 1999, now U.S. Pat. No. 7,128,073, which is a continuation-in-part of U.S. application Ser. No. 09/187,200, filed Nov. 6, 1998, now U.S. Pat. No. 6,152,144, the disclosures of which are incorporated in their entireties herein by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     Embolic stroke is the nation&#39;s third leading killer for adults, and is a major cause of disability. There are over 700,000 strokes per year in the United States alone. Of these, roughly 100,000 are hemoragic, and 600,000 are ischemic (either due to vessel narrowing or to embolism). The most common cause of embolic stroke emanating from the heart is thrombus formation due to atrial fibrillation. Approximately 80,000 strokes per year are attributable to atrial fibrillation. Atrial fibrillation is an arrhythmia of the heart that results in a rapid and chaotic heartbeat that produces lower cardiac output and irregular and turbulent blood flow in the vascular system. There are over five million people worldwide with atrial fibrillation, with about four hundred thousand new cases reported each year. Atrial fibrillation is associated with a 500 percent greater risk of stroke due to the condition. A patient with atrial fibrillation typically has a significantly decreased quality of life due, in part, to the fear of a stroke, and the pharmaceutical regimen necessary to reduce that risk. 
     For patients who develop atrial thrombus from atrial fibrillation, the clot normally occurs in the left atrial appendage (LAA) of the heart. The LAA is a cavity which looks like a small finger or windsock and which is connected to the lateral wall of the left atrium between the mitral valve and the root of the left pulmonary vein. The LAA normally contracts with the rest of the left atrium during a normal heart cycle, thus keeping blood from becoming stagnant therein, but often fails to contract with any vigor in patients experiencing atrial fibrillation due to the discoordinate electrical signals associated with AF. As a result, thrombus formation is predisposed to form in the stagnant blood within the LAA. 
     Blackshear and Odell have reported that of the 1288 patients with non-rheumatic atrial fibrillation involved in their study, 221 (17%) had thrombus detected in the left atrium of the heart. Blackshear J L, Odell J A., Appendage Obliteration to Reduce Stroke in Cardiac Surgical Patients With Atrial Fibrillation. Ann Thorac. Surg., 1996. 61(2):755-9. Of the patients with atrial thrombus, 201 (91%) had the atrial thrombus located within the left atrial appendage. The foregoing suggests that the elimination or containment of thrombus formed within the LAA of patients with atrial fibrillation would significantly reduce the incidence of stroke in those patients. 
     Pharmacological therapies for stroke prevention such as oral or systemic administration of warfarin or the like have been inadequate due to serious side effects of the medications and lack of patient compliance in taking the medication. Invasive surgical or thorascopic techniques have been used to obliterate the LAA, however, many patients are not suitable candidates for such surgical procedures due to a compromised condition or having previously undergone cardiac surgery. In addition, the perceived risks of even a thorascopic surgical procedure often outweigh the potential benefits. See Blackshear and Odell, above. See also Lindsay B D., Obliteration of the Left Atrial Appendage: A Concept Worth Testing, Ann Thorac. Surg., 1996. 61(2):515. 
     Despite the various efforts in the prior art, there remains a need for a minimally invasive method and associated devices for reducing the risk of thrombus formation in the left atrial appendage. 
     SUMMARY OF THE INVENTION 
     There is provided in accordance with one aspect of the present invention, a method of occluding an atrial appendage. The method comprises the steps of inhibiting changes in the volume of the appendage, and occluding the opening to the appendage. The inhibiting changes in the volume step preferably comprises introducing a bulking element into the appendage to resist compression of the appendage wall. Preferably, the bulking element is an expandable element. In one embodiment, the introducing an expandable bulking element step comprises deploying a self-expandable bulking element from a deployment catheter. The occluding step comprises positioning an occlusion element to enclose the bulking element within the appendage. 
     In accordance with another aspect of the present invention, there is provided a method of facilitating cell growth onto an atrial appendage occlusion device. The method comprises the steps of positioning an occlusion device across the opening of the appendage, the occlusion device having a tissue attachment surface thereon. The method additionally comprises the step of resisting compression of the appendage at least during a tissue attachment period of time. The resisting step preferably comprises positioning a bulking structure within the appendage. 
     In accordance with a further aspect of the present invention, there is provided an occlusion device for implantation within the left atrial appendage. The occlusion device comprises an occluding member, enlargeable from a reduced cross section to an enlarged cross section. The occlusion device may further comprise a stabilizing member, enlargeable from a reduced cross section to an enlarged cross section. The enlarged cross section of the stabilizing member may be less than the enlarged cross section of the occlusion member. Any of the occluding member and stabilizing member structures disclosed herein can be provided as an occluding member alone, without the corresponding stabilizing member. 
     The occlusion device preferably further comprises a hub between the occlusion member and the stabilizing member. The occlusion member comprises an expandable frame, which may be made from at least two spokes. Each spoke has a first end and a second end, and the first end is attached to the hub. The spokes are movable between an axial orientation to provide a low profile such as for transluminal implantation, and a radially enlarged orientation such as during implantation within the appendage to occlude the appendage. 
     The stabilizing member comprises at least two elements which are movable from an axial orientation when the stabilizing member is in the reduced cross section to an inclined orientation when the stabilizing member is in the enlarged cross section. In one embodiment, each element comprises a proximal section, a distal section, and a bend in-between the proximal and distal sections when the stabilizing member is in the enlarged cross section. Preferably, the occlusion device further comprises at least one tissue attachment element such as a hook, spike or barb. 
     In accordance with a further aspect of the present invention, there is provided an occlusion device for occluding a tubular body structure. The occlusion device comprises a body, having a longitudinal axis. An expandable occlusion member is provided at a first position on the axis, and a stabilizing member is provided at a second position on the axis. The occlusion member comprises a plurality of spokes which are hingeably attached to the body and movable between an axial orientation and an inclined orientation. 
     Preferably, the occlusion member further comprises a polymeric membrane carried by the spokes. The stabilizing member comprises at least three radially outwardly movable elements. In one embodiment, a hinge is provided on the body between the occlusion member and the stabilizing member. One hinge construction comprises a helical coil. 
     In accordance with a further aspect of the present invention, there is provided a method of making an occlusion device. The method comprises the steps of providing a tube, having a first end, a second end, and a longitudinal axis. A plurality of axially extending slots are cut at a first position on the tube, to create a first plurality of longitudinal elements. A second plurality of axially extending slots are cut at a second position on the tube, to create a second plurality of longitudinal elements. 
     The method further comprises the steps of providing a radially outwardly directed bias on at least one of the first and second plurality of elements. A polymeric membrane may be attached to at least one of the first and second plurality of elements. In one embodiment, a hinge is provided on the tube in-between the first and second plurality of elements. 
     In accordance with a further aspect of the present invention, there is provided a method of occluding an atrial appendage. The method comprises the steps of introducing a stabilizing member into the appendage, for resisting compression of the appendage wall, and preventing rotation and axial migration of the implant, and positioning an occlusion member across the appendage. The introducing step preferably comprises introducing a radially expandable stabilizing member, and radially expanding the member within the appendage. The positioning step may comprise either positioning the occlusion member within the appendage, or positioning the occlusion member across an opening of the appendage. In one embodiment, the introducing and positioning steps are accomplished by introducing a deployment catheter within the appendage and deploying the stabilizing member and occluding member from the catheter. Preferably, the method further comprises the step of facilitating cell growth onto the occlusion member. 
     Further features and advantages of the present invention will become apparent to those of ordinary skill in the art in view of the detailed description of preferred embodiments which follows, when considered together with the attached drawings and claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  shows a perspective view of an embodiment having features of the invention with an occluding member and a retention member. 
         FIG. 2  shows an end view of the apparatus of  FIG. 1  in partial section. 
         FIG. 3  shows a longitudinal cross-sectional view of the apparatus of  FIGS. 1 and 2 . 
         FIG. 3A  shows a perspective view of an apparatus having features of the invention. 
         FIG. 3B  shows an elevational view in partial section of the apparatus of  FIG. 3A . 
         FIG. 4  shows an elevational view of an apparatus having features of the invention in a deployed state within a body cavity. 
         FIG. 5  shows an elevational view of an apparatus having features of the invention in a deployed state within a body cavity. 
         FIG. 6  shows a perspective view of an apparatus for sealing off a body cavity having features of the invention. 
         FIG. 7  shows an elevational view in partial section of an apparatus for sealing off a body cavity having features of the invention. 
         FIG. 8  shows a transverse cross-sectional view of the apparatus of  FIG. 7  taken along lines  8 - 8 . 
         FIG. 9  shows a schematic view of a patient&#39;s heart with a transeptal catheter deployed through the septum and a delivery catheter and apparatus for sealing off a body cavity disposed therein. 
         FIG. 10  shows a schematic view of a patient&#39;s heart in partial section with a delivery catheter disposed within the opening of the LAA. 
         FIG. 11  shows a magnified view of the delivery catheter distal end and the LAA of a patient of  FIG. 10  with an apparatus for sealing off a body cavity partially deployed within the LAA. 
         FIG. 12  shows the apparatus for sealing off a body cavity of  FIG. 11  fully deployed within a LAA. 
         FIG. 13  shows an elevational view of a device for occluding a body cavity having features of the invention. 
         FIG. 14  shows a transverse cross sectional view of the device for occluding a body cavity of  FIG. 13  taken along lines  14 - 14 . 
         FIG. 15  shows a device for occluding a body cavity having features of the invention deployed within a LAA. 
         FIG. 16  shows a device for occluding a body cavity having features of the invention deployed within a LAA. 
         FIG. 17  shows a LAA being occluded by a method having features of the invention. 
         FIG. 18  shows a LAA occluded by method having features of the invention. 
         FIG. 19  shows a LAA occluded by method having features of the invention. 
         FIG. 20  is an elevational view of an apparatus for closing an interior body cavity of a patient in partial section having features of the invention. 
         FIG. 21  is a schematic view of an apparatus for closing an interior body cavity of a patient in contact with tissue of a LAA. 
         FIG. 22  is a schematic view of an apparatus for closing an interior body cavity of a patient in contact with tissue of a LAA. 
         FIG. 23  shows a LAA which has been closed by a method having features of the invention. 
         FIG. 24  is a perspective view of an occlusion device in accordance with the present invention. 
         FIG. 25  is a side elevational view of the occlusion device shown in  FIG. 24 . 
         FIG. 26  is a perspective view of an alternate embodiment of the present invention. 
         FIG. 27  is a side elevational view of the embodiment shown in  FIG. 26 . 
         FIG. 28  is a perspective view of a further embodiment of the present invention. 
         FIG. 29  is a side elevational view of the embodiment of  FIG. 28 . 
         FIG. 30  is a perspective view of a further occlusion device in accordance with the present invention. 
         FIG. 30A  is a side elevational view of the embodiment of  FIG. 30 . 
         FIG. 31  is an end view taken along the line  31 - 31  of  FIG. 30 . 
         FIG. 32  is a schematic illustration of an inflatable balloon positioned within the occlusion device of  FIG. 30 . 
         FIG. 33  is a schematic view of a pull string deployment embodiment of the occlusion device of  FIG. 30 . 
         FIGS. 34A and 34B  are side elevational schematic representations of partial and complete barrier layers on the occlusion device of  FIG. 30 . 
         FIG. 35  is a side elevational schematic view of an alternate occlusion device in accordance with the present invention. 
         FIG. 36  is a schematic view of a bonding layer mesh for use in forming a composite barrier membrane in accordance with the present invention. 
         FIG. 37  is an exploded cross sectional view of the components of a composite barrier member in accordance with the present invention. 
         FIG. 38  is a cross sectional view through a composite barrier formed from the components illustrated in  FIG. 37 . 
         FIG. 39  is a top plan view of the composite barrier illustrated in  FIG. 38 . 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       FIGS. 1-3  show an embodiment of an occluding device  10  having features of the invention where an occluding member  11  is secured to a retention member  12  that is arranged to fix the occluding member in a desired position within a body passageway or cavity. The occluding member  11  generally has disc shape with an outer rim  13  around the perimeter of a frame structure  14  which supports a barrier  15 . The outer rim  13  can be circular or polygonal, or any other shape that is suitable for conforming to the inside surface of a body cavity. A hub  16  can be located near the center of the occluding member  11  which serves to connect the retention member  12  to the occluding member, in addition to other functions. The outer rim  13  is typically made from a soft polymer material  17  which permits flexibility of the outer rim and facilitates sealing of the outer rim against the inside surface of a body cavity or passageway. The barrier  15  can be a thin mesh or film of material which serves to block the passage of material within an area surrounded by the outer rim  13 . The barrier  15  can be secured to the outer rim  13  along its entire perimeter  18  in order to achieve a complete seal therebetween and can be molded into the outer rim  13  or bonded thereto by a suitable method such as gluing, welding, sewing or other suitable method. 
     The outer rim  13  is at least partially supported by the frame structure  14  which connects the outer rim and the hub. The frame structure  14  can be made from one or more elements of high strength material such as stainless steel or MP35N, or may preferably be made from shape memory or pseudoelastic alloys such as NiTi, or any of a variety of known structural biodegradable materials (e.g. polyglycolic acid, poly lactic acid, poly-L-lactic acid and derivatives or copolymers such as PLGA). Preferably, the frame structure  14  is made from a material which can be self-expanding from a constrained configuration so that the occluding device  10  can be delivered to the deployment site in a low profile an flexible configuration which facilitates percutaneous delivery. 
     Preferably a radial hoop  21  is contained within the soft polymer material  17  of the outer rim  13  and serves to maintain the annular shape of the outer rim and facilitate radial expansion of the outer rim from a constrained position or configuration. The radial hoop  21  may be isolated within the soft polymer material  17  of the outer rim  13 , or may be connected to at least some of the elements  22  of the frame structure  14 , in order to have stronger mechanical joint between the outer rim and the frame structure. The radial hoop  21  is shown in a substantially circular configuration, but may also be polygonal or otherwise suitably shared, and may have connections or joints spaced thereon to facilitate contraction or folding of the device for non-invasive delivery. 
     In addition to connecting the retention member  12  and the occluding member  11 , the hub  16  may serve to house a rotational coupling  23  which is connected to the proximal end  24  of a tissue penetrating shaft  25  within the retention member. The rotational coupling  23  allows the transfer of torque to the tissue penetrating shaft  25  which preferably has a helically shaped extension or distal extremity  26  which is configured to screw into tissue and be mechanically fixed thereto. Longitudinal movement of the tissue penetrating shaft  25  relative to the retention member  12  and hub  16  may be prevented by sizing a lumen  27  of the retention member which contains the tissue penetrating shaft such that the helically shaped extension  26  at the distal end is too large to pass through the lumen and the proximal end  24  of the tissue penetrating shaft is prevented from passing through the lumen by the rotational coupling attached thereto. The rotational coupling  23  may also be configured to be longitudinally captured by the hub  16  but still be rotatably disposed therein. 
       FIGS. 3A and 3B  depict an alternative embodiment of an occluding device  10  having an occluding member  11  and a retention member  12 . The retention member  12  has a shaft  28  and radially extending members  29  extending radially from a proximal end of the shaft. The radially extending members  29  serve to anchor the shaft  28  and the occluding member  11  by engaging the tissue surrounding the occluding device. Preferably, the radially extending members are self-expanding from a constricted state and are made of a pseudo elastic alloy such as NiTi, or a high strength material such as stainless steel. Although it is preferable for the radially extending members  29  to be self-expanding from a constricted state, they may also be expanded by use of shape memory properties or a radial outward force as would be provided by an inflatable balloon or the like. The shaft  28  can be a single element or made of multiple elements, and can be made from the same materials as the radially extending members or different materials such as polymers or polymer composites. The radially extending members  29  have a proximally directed bias at their radial extremities  29 A so that the members readily fold down and move easily in a distal direction during insertion of the occluding device  10 , but spring outward and aggressively engage surrounding tissue upon movement in a proximal direction. This configuration of the radially extending members  29  allows easy insertion into a body cavity, but prevents egress of the device  10  in and outward or proximal direction. 
       FIG. 4  depicts an occluding device  30  similar to that depicted in  FIGS. 1-3  deployed within the left atrial appendage  31  of a patient. An outer rim or periphery  32  of the occluding device  30  is disposed adjacent the opening  33  of the left atrial appendage  31  in a position which allows for a substantial seal of the outer rim against the inside surface  34  of the LAA. A helically shaped distal extremity  35  of a tissue penetrating shaft  36  has been screwed into the wall tissue of the LAA and is mechanically secured thereto. A retention member  38  maintains the position of an occluding member  41  in a substantially perpendicular orientation with respect to a longitudinal axis of the LAA  42 . 
       FIG. 5  depicts an occluding device similar to that depicted in  FIGS. 1-4  deployed within a LAA  51  of a patient similar to what is shown in  FIG. 4 . The structure of an occluding member  52  of the embodiment as shown in  FIG. 5  differs from that shown in  FIG. 4  in that a barrier  53  and frame structure  54  of the embodiment of  FIG. 5  protrudes proximally from a plane defined by an outer rim  55 . This configuration may be useful for certain morphologies of patient&#39;s LAAs. One object of the invention is to create a smooth surface outside the body passageway or cavity in order to prevent turbulent flow or eddies of blood or other bodily fluid within the cavity or passageway. The alternative configuration of the occluding device  50  shown in  FIG. 5  may be useful in this regard. 
       FIG. 6  shows an alternative embodiment of an occluding device  60  which has an occluding member  61 , a frame structure  62 , a barrier  63  and a retention member in the form of an expandable member  65  which has linked elements  66  that are preferably expandable from a constrained configuration. The expandable member  65  is generally cylindrical in shape and can have a series of circumferential linked elements  66  connected by links  68 . Although  FIG. 6  depicts the expandable member  65  as a series of linked elements  66 , those skilled in the art will realize that a similar effect can be achieved with a single wire in a helical configuration or a plurality of wires in a mesh or braided configuration, or any other suitable configuration that can be self-expanding from a constrained configuration or expanding with the application of heat or other form of energy or force. For example, the expandable member  65  may be configured to be deployed by an outward radial force delivered from within the expandable member. An inflatable balloon or the like could be used to exert such a force. The expandable member is preferably secured to an outer rim  71  of the occluding member  61  but may also be secured to the frame structure  62  directly or indirectly. The expandable member  65  can be self-expanding from a constrained configuration as can the occluding member  61  and the frame structure  62  and outer rim  71  thereof. The frame structure  62 , outer rim  71  and barrier  63  may have construction similar to that described above with regard to the similar elements of the embodiments depicted in  FIGS. 1-5 . 
     Referring to  FIG. 7 , the expandable member  65  as shown in  FIG. 6  may also have a sheath  72  disposed around it so as to act as a shield between the expandable member and an inner surface of a patient&#39;s body cavity or passageway. The sheath  72  may facilitate the sealing function of the occluding member  61 , but is primarily intended to prevent damage to either tissue on the inside surface of a body cavity or to the linked elements  66  of the expandable member. The sheath  72  may surround all or part of the expandable member  65  and may be made from a variety of suitable biocompatible materials such as Dacron . . .™ . . . , Nylon, TFE, PTFE or ePTFE. The sheath  72  may be a weave, braid, film or have any other suitable configuration. Expandable member  65  may also be coated by dipping, spraying, or other suitable process with a friction reducing material such as Teflon . . .™ . . . , or with an active compound such as heparin. 
       FIG. 8  shows a transverse cross-sectional view of the embodiment of  FIG. 7  taken at lines  8 - 8 . The frame structure  62  has an axis or hub  73  disposed at approximately the center of the frame structure which serves to connect the various radial elements  74  of the frame structure. The hub  73  can have an independent structure that links the several elements  74  of the frame structure  62  or it may be merely the terminus of the various frame structure elements and have a solid composition. In either structure, the hub  73  preferably allows a constrained configuration of the occluding member  61  to facilitate percutaneous delivery of the occluding device  60 . The hub  73  may also have a lumen disposed therein to allow passage of a guidewire of other guiding member. Preferably, the lumen would have a self sealing valve or gasket which prevents the passage of fluid or embolic material once the guidewire or guiding member is removed from the lumen. 
     Referring to  FIG. 9 , a schematic view of a patient&#39;s heart  80  in partial section shows a trans-septal catheter  81  having a proximal end  82  and a distal end  83 . The distal end  83  of the trans-septal catheter  81  is disposed within a patient&#39;s heart  80  with the distal end  84  of a delivery catheter  85  extending from the distal end  83  of the trans-septal catheter. The distal end  83  of the trans-septal catheter  81  has breached the septum  86  of the patient&#39;s heart  80  and is disposed adjacent the opening of the patient&#39;s LAA  88 . At the proximal end  82  of the trans-septal catheter  81  there is a Luer connector  91  coupled to a hemostasis valve  92  which prevents the egress of blood from a lumen  93  of the trans-septal catheter  81 . The proximal end  94  of the delivery catheter  85  extends proximally from the hemostasis valve  92  and has a Luer connector  95  attached to the proximal extremity thereof. The proximal end  96  of a plunger  97  extends from the Luer connector  95  of the delivery catheter. The proximal end  94  of the delivery catheter is arranged to allow rotational and axial movement of the plunger  97  while preventing blood or other bodily fluids from leaking between the delivery catheter  85  and the plunger  97 . 
     Referring to  FIG. 10 , a patient&#39;s heart  80  is shown in partial section with the distal end  84  of a delivery catheter  85  disposed within the LAA opening  87 .  FIG. 11  is a magnified view of the LAA  88  shown in  FIG. 10  and the distal end of the delivery catheter  84 , which is shown in partial section, contains a plunger  97  which is slideably disposed within an inner lumen  98  of the delivery catheter  85  and serves to apply axial force in a distal direction on the collapsed occluding member  101  disposed within the delivery catheter so as to force the occluding device  102  from the delivery catheter and deploy it. An occluding device  102  having an expandable member  103  and an occluding member  101  secured thereto is partially deployed and extending from the distal end of the delivery catheter  84  into the patient&#39;s LAA  88 . The occluding device  102  can also be guided into the patient&#39;s LAA  88  by use of an appropriate guidewire or guiding member. 
       FIG. 12  shows the occluding device  102  of  FIG. 11  in a deployed state within the patient&#39;s LAA  88 . An outer rim  104  of the occluding member  101  is in substantial sealing contact with the inside surface  105  of the LAA  88 . The expandable member  103  has expanded so as to contact the inside surface  105  of the LAA and secure the occluding device  102  thereto and maintain the occluding member  101  in a substantially perpendicular orientation relative to a longitudinal axis  106  of the LAA  88 . A barrier  107  is disposed within an area bounded by the outer rim  104  and is positioned to prevent the passage or embolic or other material to or from the LAA  88 . The distal end  108  of the plunger  97  is extending from the distal end of the delivery catheter  84  after having pushed the occluding device  102  from the delivery catheter. 
     Referring to  FIG. 13 , an occluding device  110  having features of the invention is shown. The occluding device  110  has a delivery catheter  111  with a distal end  112 , a detachment mechanism  113  disposed on the distal end of the delivery catheter and an occlusive body or inflatable member  114  detachably secured to the detachment mechanism. The inflatable member  114  has a proximal end  115  and a distal end  116  with the proximal end being attached to the detachment mechanism  113  and the distal end terminating at an end cap  117 . The inflatable member  114  has an outside surface  118  that may contain a fibrosis inducing material such as Dacron . . .™ . . . or other similar materials. The inflatable member  114  may be made from a fluid tight film of polymer material which can be either compliant or non-compliant. Preferably the inflatable member  114  is made from silicone, however, any suitable material such as polyethylene, polyurethane or PET can be used. 
     The detachment mechanism  113  can be activated by mechanical force or by delivery of thermal or optical energy by a suitable conduit. Alternatively, the inflatable member can be pushed into the LAA from the delivery catheter  111  by an elongate push member without the use of a detachment mechanism. The inflatable member  114  can be filled with a gas, fluid or gel which is injected under pressure through the delivery catheter  114  and into the inflatable member. Suitable fluids to inject would include saline and silicone. The inflatable member  114  may also be filled with a polymer material that can be hardened. Autologus fluid such as blood, or collagen may also be used. A fluid, gel or polymer used to fill the inflatable member may contain contrast agents such as gold, tantalum, bismuth, barium sulfate or the like in order to improve visualization under fluoroscopy or x-ray imaging. 
       FIG. 14  is a transverse cross-sectional view of the occluding device  110  of  FIG. 13  taken along lines  14 - 14 . An optional inner shaft  121  is shown disposed within the inflatable member  114 , preferably in a concentric arrangement. The inner shaft  121  provides longitudinal axial support to the inflatable member  114  so as to maintain a longitudinal dimension of the inflatable member  114  when it is being inflated and deployed. The inner shaft  121  may be solid or contain one or more lumens that may or may not be in fluid communication with an inner lumen  122  of the inflatable member  114 , and can be used for the passage of a guidewire or guiding member. 
       FIG. 15  depicts an alternative embodiment of an occluding device  110  which consists of an inflatable member  114  similar to the inflatable member of  FIG. 13 , shown substantially deployed, within a patient&#39;s LAA  123 . The inflatable member  114  has been at least partially filled with a fluid, gas or gel, within the patient&#39;s LAA  123  such that the outside surface of the inflatable member  118  is in contact with at least part of the inside surface  124  of the LAA. The inflatable member  114  can have rib members  125  which can mechanically interlock with the trebeculae  126  of the inside surface of the LAA  124  or other surface irregularities of the inside surface of a patient&#39;s body cavity or passageway. The rib members  125  form a complete circumference of the inflatable member  114 , but could also form a partial circumference, spiral configuration, or consist of random projections on the surface of the inflatable member  118 . The rib members  125  should extend radially about 1 to about 4 mm from the nominal surface of the inflatable member  114 , and are preferably spaced about 3 to about 8 mm from each other. The rib members  125  may be made from any suitable polymer material, but are preferably made from the same material as the inflatable member, and are integrally molded thereon, or bonded thereto with a heat weld or adhesive bond suitable for bonding flexibly medical polymers. The inflatable member  114  is depicted with the distal end of the delivery catheter  112  and detachment mechanism  113  attached. As an alternative, or in addition to the polymer rib members  125  shown in  FIG. 15 , barbs or hooks could be secured to the outside surface of the inflatable member  114  which are configured to engage the inside surface of a patient&#39;s LAA  124 . Preferably, barbs or hooks disposed on the outside surface of the inflatable member and configured to engage the tissue of the inside surface of a patient&#39;s LAA  124  would have a proximally directed bias at their radial extremity so that the barbs would fold down and move easily in a distal direction during insertion of the inflatable member  114 , but would spring outward and aggressively engage the tissue of the body cavity upon movement in a proximal direction of the inflatable member. 
       FIG. 16  depicts an occluding device  110  consisting of an inflatable member  114  which is shown deployed within a patient&#39;s LAA  123 . The embodiment of the inflatable member  114  shown in  FIG. 16  has an optional retention member  127  with a tissue penetrating shaft  128  which has a proximal  131  end and a distal end  132 . A rotational coupling  133  is disposed at the proximal end  131  of the tissue penetrating shaft  128  and a helically shaped extremity  134  is disposed at the distal end of the shaft  132 . The helically shaped distal extremity  134  is shown deployed within and mechanically engaging wall tissue  135  of the LAA so as to secure the inflatable member  114  and maintain its position within the LAA  123  of the patient. 
       FIG. 17  shows an alternative embodiment of an occlusive member  140  consisting of a polymer mass  141  which has been injected or delivered into a patient&#39;s LAA  142 . The distal end  143  of a delivery catheter  144  has a lumen  145  therein which extends to a proximal end of the delivery catheter which is in fluid communication with a source of pressurized polymer material. A source of pressurized polymer material  146  can be any type of pump or device capable of forcing a polymer fluid or gel into the proximal end of the delivery catheter with sufficient pressure to force the polymer fluid or gel out the distal end  143  of the delivery catheter  144  and into a patient&#39;s body cavity or passageway. 
     The delivery catheter  144  may be positioned by the techniques discussed above, e.g., the Mullins trans-septal approach or any other suitable method. Once the distal end of the delivery catheter  143  is disposed within a desired portion of the patient&#39;s LAA  142 , the polymer mass  141  may be injected to fill the cavity to the desired level. The LAA  142  can be completely or partially filled with the polymer mass  141  which can be formulated to harden over time, with heat or remain in a fluid or gel state. The distal end of the delivery catheter can optionally include an expandable member which is used to substantially seal the delivery catheter against the inside surface of the opening of the patient&#39;s body cavity during the delivery of polymer material. The expandable member can be an inflatable balloon or the like which are well known in the art. 
     Optionally, a retention member  127  having a tissue penetrating shaft  128  or the like, such as shown in  FIG. 16  with regard to the inflatable member  114 , may be deployed within the LAA  142  prior to injection of the polymer mass  141  and captured thereby so as to secure the polymer mass within the LAA. Alternatively, the polymer mass can be used to fill the patient&#39;s LAA and surround and secure a deployed device as shown in  FIG. 4  or  5  in the patient&#39;s LAA  142 . 
     Once a desired amount of polymer mass  141  has been injected into the LAA  142 , as assessed for example by TE Echo imaging, the delivery catheter  144  may be withdrawn and the procedure terminated. Preferably, the entire LAA  142  of a patient is filled with the polymer mass  141  as shown in  FIG. 18  and hardens or gels to maintain its shape. It may be desirable to have the polymer mass  141  retain a soft compressible form after setting or hardening so that it is at least partially compliant with the constrictive pumping action of a heart and resistant to fatigue as a result thereof. A material used to form the polymer mass  141  may contain contrast agents such as gold, platinum, tantalum, bismuth or the like in order to better visualize the deployment of the polymer mass under fluoroscopic or x-ray imaging. 
     Another alternative embodiment of an occlusive member  140  can be found in  FIG. 19  which shows an occlusive coil  147  which has been deployed within an LAA  142 . The occlusive coil  147  as shown has assumed a random configuration that is mechanically occluding the LAA  142  and which has induced clot and/or fibrosis formation  148  which further facilitates occlusion of the LAA  142 . 
     An apparatus for closing off a body cavity or passageway  150  is shown in  FIG. 20  which has features of the present invention. The apparatus  150  has an elongate shaft  151  with an inner lumen  152  and a proximal end  153  and a distal end  154 . Slideably disposed within the inner lumen  152  of the elongate shaft  151  are at least two elongate members  155  which have proximal ends  156  and distal ends  157  and have tissue attachment members  158  disposed on the distal ends. An optional distal anchor member  161  is also slideably disposed within the inner lumen  152  of the elongate shaft  151  and preferably has a distal end  162  terminating with a helical member  163 . The proximal end  153  of the elongate shaft  151  has a proximal control module  164  which seals the inner lumen  152  of the elongate shaft  151  and allows rotation and translation of the proximal ends  156  of the elongate members  155  and the distal anchor member  161  while maintaining a seal between said members to prevent leakage of bodily fluids therefrom. The proximal control module  164  can optionally be configured to control advancement and retraction of the elongate members  155  and control activation of the tissue attachment members  158 . 
       FIG. 21  shows the apparatus for closing off a body cavity  150  of  FIG. 20  with the distal ends of the elongate members  157  and the tissue attachment members  158  extending distally from the distal end of the elongate shaft  154 . The distal ends of the elongate members  157  are angled or deflected from a longitudinal axis  165  of the elongate shaft  151  so as to engage tissue  166  of the opening  167  of the LAA  168  as shown. The elongate members  155  may be deflected by an abutment or angulation contained in the distal end of the elongate shaft  154 , but are preferably preshaped in an angled configuration which manifests when the distal ends are freed of the constraint of the inner lumen  152  of the elongate shaft an allowed to assume their relaxed preshaped condition. The helical member  163  at the distal end  162  of the distal anchor member  161  is engaged with the wall tissue  171  of the LAA  168  so as to provide an optional anchor that can be used to move the elongate shaft  151  relative to the distal anchor member  161  and give greater control of the longitudinal axial movement of the elongate shaft relative to the LAA opening  167 . The tissue attachment members  158  are shown attached to the annular edge  172  of the LAA opening  167 . Once the tissue attachment members  158  are attached, a closure member or retaining ring  173  may be advanced distally by applying axial force on an elongate push shaft  174  which draws the tissue attachment members  158  and the tissue attached thereto closer together as shown in  FIG. 22 . As the closure member  173  is further advanced distally, the annular edge of the LAA  172  is drawn closed, and eventually, the annular edge of the LAA will be completely closed into a closed state with the closure member  173  surrounding and compressing the tissue of the annular edge as shown in  FIG. 23 . Once a closed state of the LAA is achieved, the tissue attachment members  158  may be detached, and the apparatus for closing off a body cavity  150  withdrawn. One alternative method can have the tissue attachment members  158  drawn together by retracting them proximally into the distal end  154  of the elongate shaft  151  as opposed to distally advancing the closure member  173  with the elongate push shaft  174 . In this way, the annular edge of the LAA  172  can be drawn into a closed state within the distal end  154  of the elongate shaft  151  at which point the annular edge may be fixed in the closed state by a variety of methods including suturing, tissue welding, the application of a suitable biocompatible adhesive, surgical staples or the like. 
     Referring to  FIGS. 24 and 25 , there is illustrated an alternate embodiment of the occlusion device  10  in accordance with the present invention. The occlusion device  10  comprises an occluding member  11  comprising a frame  14  and a barrier  15 . In the illustrated embodiment, the frame  14  comprises a plurality of radially outwardly extending spokes  17  each having a length within the range of from about 0.5 cm to about 2 cm from a hub  16 . In one embodiment, the spokes have an axial length of about 1.5 cm. Depending upon the desired introduction crossing profile of the collapsed occlusion device  10 , as well as structural strength requirements in the deployed device, anywhere within the range of from about 3 spokes to about 40 spokes may be utilized. In some embodiments, anywhere from about 12 to about 24 spokes are utilized, and, 18 spokes are utilized in one embodiment. 
     The spokes are advanceable from a generally axially extending orientation such as to fit within a tubular introduction catheter to a radially inclined orientation as illustrated in  FIG. 24  and  FIG. 25  following deployment from the catheter. In a self-expandable embodiment, the spokes are biased radially outwardly such that the occlusion member expands to its enlarged, implantation cross-section under its own bias following deployment from the catheter. Alternatively, the occlusion member may be enlarged using any of a variety of enlargement structures such as an inflatable balloon. 
     Preferably, the spokes comprise a metal such as stainless steel, Nitinol, Elgiloy, or others which can be determined through routine experimentation by those of skill in the art. Wires having a circular or rectangular cross-section may be utilized depending upon the manufacturing technique. In one embodiment, rectangular cross section spokes are cut such as by known laser cutting techniques from tube stock, a portion of which forms the hub  16 . 
     The barrier  15  may comprise any of a variety of materials which facilitate cellular in-growth, such as ePTFE. The suitability of alternate materials for barrier  15  can be determined through routine experimentation by those of skill in the art. The barrier  15  may be provided on either one or both sides of the occlusion member. In one embodiment, the barrier  15  comprises two layers, with one layer on each side of the frame  14 . The two layers may be bonded to each other around the spokes  17  in any of a variety of ways, such as by heat bonding with or without an intermediate bonding layer such as polyethylene or FEP, adhesives, sutures, and other techniques which will be apparent to those of skill in the art in view of the disclosure herein. The barrier  15  preferably has a thickness of no more than about 0.003″ and a porosity within the range of from about 5 .mu.m to about 60 .mu.m. 
     The barrier  15  in one embodiment preferably is securely attached to the frame  14  and retains a sufficient porosity to facilitate cellular ingrowth and/or attachment. One method of manufacturing a suitable composite membrane barrier  15  is illustrated in  FIGS. 36-39 . As illustrated schematically in  FIG. 36 , a bonding layer  254  preferably comprises a mesh or other porous structure having an open surface area within the range of from about 10% to about 90%. Preferably, the open surface area of the mesh is within the range of from about 30% to about 60%. The opening or pore size of the bonding layer  254  is preferably within the range of from about 0.005 inches to about 0.050 inches, and, in one embodiment, is about 0.020 inches. The thickness of the bonding layer  254  can be varied widely, and is generally within the range of from about 0.0005 inches to about 0.005 inches. In a preferred embodiment, the bonding layer  254  has a thickness of about 0.001 to about 0.002 inches. One suitable polyethylene bonding mesh is available from Smith and Nephew, under the code SN9. 
     Referring to  FIG. 37 , the bonding layer  254  is preferably placed adjacent one or both sides of a spoke or other frame element  14 . The bonding layer  254  and frame  14  layers are then positioned in-between a first membrane  250  and a second membrane  252  to provide a composite membrane stack. The first membrane  250  and second  252  may comprise any of a variety of materials and thicknesses, depending upon the desired functional result. Generally, the membrane has a thickness within the range of from about 0.0005 inches to about 0.010 inches. In one embodiment, the membranes  250  and  252  each have a thickness on the order of from about 0.001 inches to about 0.002 inches, and comprise porous ePTFE, having a porosity within the range of from about 10 microns to about 100 microns. 
     The composite stack is heated to a temperature of from about 200.degree. to about 300.degree., for about 1 minute to about 5 minutes under pressure to provide a finished composite membrane assembly with an embedded frame  14  as illustrated schematically in  FIG. 38 . The final composite membrane has a thickness within the range of from about 0.001 inches to about 0.010 inches, and, preferably, is about 0.002 to about 0.003 inches in thickness. However, the thicknesses and process parameters of the foregoing may be varied considerably, depending upon the materials of the bonding layer  254  the first layer  250  and the second layer  252 . 
     As illustrated in top plan view in  FIG. 39 , the resulting finished composite membrane has a plurality of “unbonded” windows or areas  256  suitable for cellular attachment and/or ingrowth. The attachment areas  256  are bounded by the frame  14  struts, and the cross-hatch pattern formed by the bonding layer  254 . In the illustrated embodiment, the filaments of the bonding layer  254  are oriented in a nonparallel relationship with the struts of frame  14 , and, in particular, at an angle within the range of from about 15.degree. to about 85.degree. from the longitudinal axis of the struts. Preferably, a regular window  256  pattern is produced. 
     The foregoing procedure allows the bonding mesh to flow into the first and second membranes  250  and  252  and gives the composite membrane  15  greater strength (both tensile and tear strength) than the components without the bonding mesh. The composite allows uniform bonding while maintaining porosity of the membrane  15 , to facilitate tissue attachment. By flowing the thermoplastic bonding layer into the pores of the outer mesh layers  250  and  252 , the composite flexibility is preserved and the overall composite layer thickness can be minimized. 
     The occlusion device  10  may be further provided with a bulking element or stabilizer  194 . The stabilizer  194  may be spaced apart along an axis from the occluding member  11 . In the illustrated embodiment, a distal end  190  and a proximal end  192  are identified for reference. The designation proximal or distal is not intended to indicate any particular anatomical orientation or deployment orientation within the deployment catheter. As shown in  FIGS. 24 and 25 , the stabilizer  194  is spaced distally apart from the occluding member  11 . 
     For use in the LAA, the occluding member  11  has an expanded diameter within the range of from about 1 cm to about 5 cm, and, in one embodiment, about 3 cm. The axial length of the occluding member  11  in an expanded, unstressed orientation from the distal end  192  to the proximal hub  16  is on the order of about 1 cm. The overall length of the occlusion device  10  from the distal end  192  to the proximal end  190  is within the range of from about 1.5 cm to about 4 cm and, in one embodiment, about 2.5 cm. The axial length of the stabilizer  194  between distal hub  191  and proximal hub  16  is within the range of from about 0.5 cm to about 2 cm, and, in one embodiment, about 1 cm. The expanded diameter of the stabilizer  194  is within the range of from about 0.5 cm to about 2.5 cm, and, in one embodiment, about 1.4 cm. The outside diameter of the distal hub  191  and proximal hub  16  is about 2.5 mm. 
     Preferably, the occlusion device  10  is provided with one or more retention structures for retaining the device in the left atrial appendage or other body lumen. In the illustrated embodiment, a plurality of barbs or other anchors  195  are provided, for engaging adjacent tissue to retain the occlusion device  10  in its implanted position and to limit relative movement between the tissue and the occlusion device. The illustrated anchors are provided on one or more of the spokes  17 , or other portion of frame  14 . Preferably, every spoke, every second spoke or every third spoke are provided with one or two anchors each. The illustrated anchor is in the form of a barb, for extending into tissue at or near the opening of the LAA. 
     One or more anchors  195  may also be provided on the stabilizer  194 , such that it assists not only in orienting the occlusion device  10  and resisting compression of the LAA, but also in retaining the occlusion device  10  within the LAA. Any of a wide variety of structures may be utilized for anchor  195 , either on the occluding member  11  or the stabilizer  194  or both, such as hooks, barbs, pins, sutures, adhesives and others which will be apparent to those of skill in the art in view of the disclosure herein. 
     In use, the occlusion device  10  is preferably positioned within a tubular anatomical structure to be occluded such as the left atrial appendage such that the occluding member  11  is positioned across or near the opening to the LAA and the stabilizer  194  is positioned within the LAA. The stabilizer  194  assists in the proper location and orientation of the occluding member  11 , as well as resists compression of the LAA behind the occluding member  11 . The present inventors have determined that following deployment of an occluding member  11  without a stabilizer  194  or other bulking structure to resist compression of the LAA, normal operation of the heart may cause compression and resulting volume changes in the LAA, thereby forcing fluid past the occluding member  11  and inhibiting or preventing a complete seal. Provision of a stabilizer  194  dimensioned to prevent the collapse or pumping of the LAA thus minimize leakage, and provision of the barbs facilitates endothelialization or other cell growth across the occluding member  11 . 
     For this purpose, the stabilizer  194  is preferably movable between a reduced cross-sectional profile for transluminal advancement into the left atrial appendage, and an enlarged cross-sectional orientation as illustrated to fill or to substantially fill a cross-section through the LAA. The stabilizing member may enlarge to a greater cross section than the anatomical cavity, to ensure a tight fit and minimize the likelihood of compression. One convenient construction includes a plurality of elements  196  which are radially outwardly expandable in response to axial compression of a distal hub  191  towards a proximal hub  16 . Elements  196  each comprise a distal segment  198  and a proximal segment  202  connected by a bend  200 . The elements  196  may be provided with a bias in the direction of the radially enlarged orientation as illustrated in  FIG. 25 , or may be radially expanded by applying an expansion force such as an axially compressive force between distal hub  191  and proximal hub  16  or a radial expansion force such as might be applied by an inflatable balloon: Elements  196  may conveniently be formed by laser cutting the same tube stock as utilized to construct the distal hub  191 , proximal hub  16  and frame  14 , as will be apparent to those of skill in the art in view of the disclosure herein. Alternatively, the various components of the occlusion device  10  may be separately fabricated or fabricated in subassemblies and secured together during manufacturing. 
     As a post implantation step for any of the occlusion devices disclosed herein, a radiopaque dye or other visualizable media may be introduced on one side or the other of the occlusion device, to permit visualization of any escaped blood or other fluid past the occlusion device. For example, in the context of a left atrial appendage application, the occlusion device may be provided with a capillary tube or aperture which permit introduction of a visualizable dye from the deployment catheter through the occlusion device and into the entrapped space on the distal side of the occlusion device. Alternatively, dye may be introduced into the entrapped space distal to the occlusion device such as by advancing a small gauge needle from the deployment catheter through the barrier  15  on the occlusion device, to introduce dye. 
     A further embodiment of the occlusion device  10  is illustrated in  FIGS. 26-27 . The occlusion device  10  comprises an occlusion member  11  and a stabilizing member  194  as in the previous embodiment. In the present embodiment, however, each of the distal segments  198  inclines radially outwardly in the proximal direction and terminates in a proximal end  204 . The proximal end  204  may be provided with atraumatic configuration, for pressing against, but not penetrating, the wall of the left atrial appendage or other tubular body structure. Three or more distal segments  198  are preferably provided, and generally anywhere within the range of from about 6 to about 20 distal segments  198  may be used. In one embodiment, 9 distal segments  198  are provided. In this embodiment, 3 of the distal segments  198  have an axial length of about 5 mm, and 6 of the distal segments  198  have an axial length of about 1 cm. Staggering the lengths of the proximal segments  198  may axially elongate the zone in the left atrial appendage against which the proximal ends  204  provide anchoring support for the occlusion device. 
     The occlusion device  10  illustrated in  FIGS. 26 and 27  is additionally provided with a hinge  206  to allow the longitudinal axis of the occlusion member  11  to be angularly oriented with respect to the longitudinal axis of the stabilizing member  194 . In the illustrated embodiment, the hinge  206  is a helical coil, although any of a variety of hinge structures can be utilized. The illustrated embodiment may be conveniently formed by laser cutting a helical slot through a section of the tube from which the principal structural components of the occlusion device  10  are formed. At the distal end of the hinge  206 , an annular band  208  connects the hinge  206  to a plurality of axially extending struts  210 . In the illustrated embodiment  210 , three axial struts  210  are provided, spaced equilaterally around the circumference of the body. Axial struts  210  may be formed from a portion of the wall of the original tube stock, which portion is left in its original axial orientation following formation of the distal segments  198  such as by laser cutting from the tubular wall. 
     The occlusion member  11  is provided with a proximal zone  212  on each of the spokes  17 . Proximal zone  212  has an enhanced degree of flexibility, to accommodate the fit between the occlusion member  11  and the wall of the left atrial appendage. Proximal section  212  may be formed by reducing the cross sectional area of each of the spokes  17 , or by increasing the length of each spoke by making a wave pattern as illustrated. 
     Each of the spokes  17  terminates in a proximal point  214 . Proximal point  214  may be contained within layers of the barrier  15 , or may extend through or beyond the barrier  15  such as to engage adjacent tissue and assist in retaining the occlusion device  10  at the deployment site. 
     Referring to  FIGS. 28 and 29 , a further variation on the occlusion device  10  illustrated in  FIGS. 24 and 25  is provided. The occlusion device  10  is provided with a proximal face  216  on the occlusion member  11 , instead of the open and proximally concave face on the embodiment of  FIGS. 24 and 25 . The proximal face  216  is formed by providing a proximal spoke  218  which connects at an apex  220  to each distal spoke  17 . Proximal spokes  218  are each attached to a hub  222  at the proximal end  192  of the occlusion device  10 . The barrier  15  may surround either the proximal face or the distal face or both on the occlusion member  11 . In general, provision of a proximal spoke  218  connected by an apex  220  to a distal spoke  17  provides a greater radial force than a distal spoke  17  alone, which will provide an increased resistance to compression if the occlusion member  11  is positioned with the LAA. 
     Referring to  FIGS. 30-35 , an alternate embodiment of the occlusion device in accordance with the present invention is illustrated. In general, the occlusion device  10  comprises an occluding member but does not include a distinct stabilizing member as has been illustrated in connection with previous embodiments. Any of the embodiments previously disclosed herein may also be constructed using the occluding member only, and omitting the stabilizing member as will be apparent to those of skill in the art in view of the disclosure herein. 
     The occluding device  10  comprises a proximal end  192 , a distal end  190 , and a longitudinal axis extending therebetween. A plurality of supports  228  extend between a proximal hub  222  and a distal hub  191 . At least two or three supports  228  are provided, and preferably at least about six. In one embodiment, eight supports  228  are provided. However, the precise number of supports  228  can be modified, depending upon the desired physical properties of the occlusion device  10  as will be apparent to those of skill in the art in view of the disclosure herein, without departing from the present invention. 
     Each support  228  comprises a proximal spoke portion  218 , a distal spoke portion  217 , and an apex  220  as has been discussed. However, each of the proximal spoke  218 , distal spoke  17  and apex  220  may be a region on an integral support  228 , such as a continuous rib or frame member which extends in a generally curved configuration as illustrated with a concavity facing towards the longitudinal axis of the occlusion device  10 . Thus, no distinct point or hinge at apex  220  is necessarily provided as is disclosed in previous embodiments, which include a hinged connection between proximal spoke  218  and distal spoke  17 . 
     At least some of the supports  228 , and, preferably, each support  228 , is provided with one or two or more barbs  195 . In the illustrated configuration, the occlusion device  10  is in its enlarged orientation, such as for occluding a left atrial appendage or other body cavity or lumen. In this orientation, each of the barbs  195  projects generally radially outwardly from the longitudinal axis, and are inclined in the proximal direction. In an embodiment where the barbs  195  and corresponding support  228  are cut from a single ribbon, sheet or tube stock, the barb  195  will incline radially outwardly at approximately a tangent to the curve formed by the support  228 . 
     The occlusion device  10  illustrated in  FIG. 30  may be constructed in any of a variety of ways, as will become apparent to those of skill in the art in view of the disclosure herein. In one preferred method, the occlusion device  10  is constructed by laser cutting a piece of tube stock to provide a plurality of axially extending slots in-between adjacent supports  228 . Similarly, each barb  195  can be laser cut from the corresponding support  228  or space in-between adjacent supports  228 . The generally axially extending slots which separate adjacent supports  228  end a sufficient distance from each of the proximal end  192  and distal end  190  to leave a proximal hub  222  and a distal hub  191  to which each of the supports  228  will attach. In this manner, an integral cage structure may be formed. Alternatively, each of the components of the cage structure may be separately formed and attached together such as through soldering, heat bonding, adhesives, and other fastening techniques which are known in the art. A further method of manufacturing the occlusion device  10  is to laser cut a slot pattern on a flat sheet of appropriate material, such as a flexible metal or polymer, as has been discussed in connection with previous embodiments. The flat sheet may thereafter be rolled about an axis and opposing edges bonded together to form a tubular structure. 
     The apex portion  220  which carries the barb  195  may be advanced from a low profile orientation in which each of the supports  228  extend generally parallel to the longitudinal axis, to an implanted orientation as illustrated, in which the apex  220  and the barb  195  are positioned radially outwardly from the longitudinal axis. The support  228  may be biased towards the enlarged orientation, or may be advanced to the enlarged orientation following positioning within the tubular anatomical structure, in any of a variety of manners. For example, referring to  FIG. 32 , an inflatable balloon  230  is positioned within the occlusion device  10 . Inflatable balloon  230  is connected by way of a removable coupling  232  to an inflation catheter  234 . Inflation catheter  234  is provided with an inflation lumen for providing communication between an inflation media source  236  outside of the patient and the balloon  230 . Following positioning within the target body lumen, the balloon  230  is inflated, thereby engaging barbs  195  with the surrounding tissue. The inflation catheter  234  is thereafter removed, by decoupling the removable coupling  232 , and the inflation catheter  234  is thereafter removed. 
     In an alternate embodiment, the supports  228  are radially enlarged such as through the use of a deployment catheter  238 . Deployment catheter  238  comprises a lumen for movably receiving a deployment line  240 . Deployment line  240  extends in a loop  244  formed by a slip knot  242 . As will be apparent from  FIG. 33 , proximal retraction on the deployment line  240  will cause the distal hub  191  to be drawn towards the proximal hub  222 , thereby radially enlarging the cross-sectional area of the occlusion device  10 . Depending upon the material utilized for the occlusion device  10 , the supports  228  will retain the radially enlarged orientation by elastic deformation, or may be retained in the enlarged orientation such as by securing the slip knot  242  immovably to the deployment line  240  at the fully radially enlarged orientation. This may be accomplished in any of a variety of ways, using additional knots, clips, adhesives, or other techniques known in the art. 
     Referring to  FIGS. 34A and 34B , the occlusion device  10  may be provided with a barrier  15  such as a mesh or fabric as has been previously discussed. Barrier  15  may be provided on only one hemisphere such as proximal face  216 , or may be carried by the entire occlusion device  10  from proximal end  192  to distal end  190 . The barrier may be secured to the radially inwardly facing surface of the supports  228 , as illustrated in  FIG. 34B , or may be provided on the radially outwardly facing surfaces of supports  228 , or both. 
     A further embodiment of the occlusion device  10  is illustrated in  FIG. 35 , in which the apex  220  is elongated in an axial direction to provide additional contact area between the occlusion device  10  and the wall of the tubular structure. In this embodiment, one or two or three or more anchors  195  may be provided on each support  228 , depending upon the desired clinical performance. The occlusion device  10  illustrated in  FIG. 35  may also be provided with any of a variety of other features discussed herein, such as a partial or complete barrier  15  covering. In addition, the occlusion device  10  illustrated in  FIG. 35  may be enlarged using any of the techniques disclosed elsewhere herein. 
     While particular forms of the invention have been described, it will be apparent that various modifications can be made without departing from the spirit and scope of the invention. Accordingly, it is not intended that the invention be limited, except as by the appended claims.