Patent Publication Number: US-2009228040-A1

Title: Mechanism and Method for Closing an Arteriotomy

Description:
FIELD OF THE INVENTION 
     The invention relates in general to devices and techniques for closing a percutaneous puncture in a blood vessel after an intravascular procedure. 
     BACKGROUND OF THE INVENTION 
     Various cardiovascular procedures, such as angioplasty, stent placement and atherectomy, require inserting into and manipulating within the vasculature, wires and catheters adapted to perform those procedures. Access to the vasculature typically is through the femoral artery and is percutaneous, involving insertion of a needle and introducer sheath in the region of the groin to form a track through subcutaneous tissue and to puncture and create an arteriotomy in the femoral artery. A short guidewire is then advanced through the needle and into the femoral artery. The needle then is removed. An introducer sheath is then advanced over the guidewire, along the track and into the femoral artery. The sheath provides access into the femoral artery, through the arteriotomy, for catheters or other instrumentalities in order to perform the selected procedure. 
     After the procedure has been completed, the procedural devices are removed and the arteriotomy must be closed. A number of techniques are known to facilitate closure and healing of the arteriotomy. These include application of pressure at the puncture site for a relatively extended length of time, or the use of biological adhesives or plugs adapted to seal the arteriotomy, or the use of staples or clips. Some closure systems include an arrangement to engage the artery to temporarily draw the edges of the arteriotomy together while a final closure element, such as a staple, sutures, adhesives or other means is used to affect the permanent closure of the arteriotomy. Such systems are described, for example, in U.S. Pat. No. 6,767,356 (Kanner) and U.S. Pat. No. 6,391,048 (Ginn et al.). Ginn discloses an arrangement in which several needles pierce the vessel wall surrounding the arteriotomy and then are manipulated to twist or draw together the vessel wall about the arteriotomy. Adhesives, sutures or clips then may be employed to secure a permanent closure. However, it would be desirable to provide a closure system in which tissue about the arteriotomy could be temporarily drawn together without risking the trauma from piercing the tissue. Accordingly, the present invention is directed to such an alternate mechanism and technique for closing an arteriotomy. 
     In addition, it is desirable to provide such a closure system with a very low profile. Some final closure elements, including staples, sutures, adhesives or other means used to affect the permanent closure of the arteriotomy, require relatively large delivery devices that actually enlarge the size of the arteriotomy when delivering the closure element to the target tissue. Accordingly, it is an object of the present invention to provide a closure element delivery device having a low profile in order to prevent incidental enlargement of the arteriotomy. 
     BRIEF SUMMARY OF THE INVENTION 
     Embodiments of the present invention relate to a system for closing an arteriotomy. The system includes an elongate central tube having a distal portion including a plurality of gripping elements disposed thereon, the plurality of gripping elements configured to be movable between a radially contracted configuration and a radially expanded configuration. The gripping elements may be actuated to effect a grip on tissue surrounding the arteriotomy when the gripping elements are in the radially expanded configuration. The system also includes a delivery tube disposed on an outside surface of the central tube, the delivery tube being slidable along the central tube to urge the gripping elements from the radially expanded configuration to the radially contracted configuration while maintaining grip on the tissue whereby the tissue may be puckered together. A closure element is disposed on the outside surface of the central tube, the closure element being slidable along and off a distal end of the central tube by the delivery tube and adapted to surround the puckered tissue to close the arteriotomy. 
     Embodiments of the present invention also relate to a method for closing an arteriotomy. A plurality of tissue gripping elements on a distal portion of a central tube is provided, the gripping elements being configured to be selectively movable between a radially contracted configuration and a radially expanded configuration. The gripping elements are positioned in the radially expanded configuration and disposed in surrounding relation to the arteriotomy. The gripping elements are actuated to cause them to grip the tissue surface without piercing the tissue. A closure element is provided around the outside surface of the central tube, and a delivery tube is provided about the central tube such that the delivery tube can push the closure element along the outside surface of the central tube. The delivery tube and the closure element are slidably advanced distally over the outside of the central tube until the gripping elements are collapsed to the radially contracted configuration while maintaining grip on the tissue surface whereby the tissue surrounding the arteriotomy may be puckered together. The delivery tube and the closure element are further slidably advanced distally along the outside of the central tube until the closure element is pushed off of a distal end of the central tube by the delivery tube such that the closure element surrounds the puckered tissue and permanently secures the arteriotomy closed. Thereafter the gripping elements are released from the tissue. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
       The foregoing and other features and advantages of the invention will be apparent from the following description of the invention as illustrated in the accompanying drawings. The accompanying drawings, which are incorporated herein and form a part of the specification, further serve to explain the principles of the invention and to enable a person skilled in the pertinent art to make and use the invention. The drawings are not to scale. 
         FIG. 1  illustrates a mechanism at the distal portion of the arteriotomy closure system of the present invention, as seen from a proximal oblique angle. 
         FIG. 2  illustrates the mechanism at the distal portion of the arteriotomy closure system shown in  FIG. 1 , as seen from a distal oblique angle. 
         FIG. 3  is a perspective illustration of the mechanism of  FIGS. 1 and 2 , with tissue-gripping retention fingers in a deployed position to be disposed against tissue about the arteriotomy. 
         FIG. 4  is a perspective illustration of the mechanism of  FIGS. 1-3 , with a closure element in position for advancement towards the deployed tissue-gripping retention fingers. 
         FIG. 5  illustrates the mechanism of  FIGS. 1-4 , with a delivery tube pushing the closure element along the outer surface of the tissue-gripping retention fingers, thereby radially contracting the fingers. 
         FIG. 6  illustrates the mechanism of  FIGS. 1-5 , with the closure element being pushed off of the distal tips of the contracted tissue-gripping retention fingers. 
         FIG. 7  is a transverse cross-sectional illustration of a mechanism at the distal portion of an arteriotomy closure system in accordance with the present invention, with the fingers radially contracted to purse the tissue about an arteriotomy, and with the guidewire having been removed for clarity. 
         FIG. 8  is a perspective illustration of another embodiment of a mechanism at the distal portion of an arteriotomy closure system in accordance with the present invention, as seen from a proximal oblique angle, wherein the system includes a protective sheath. 
         FIG. 9  is a perspective illustration of a delivery tube of an arteriotomy closure system according to another embodiment of the present invention. 
         FIG. 10  is a partial longitudinal sectional view of an arteriotomy closure system of the present invention, wherein the system includes the delivery tube of  FIG. 9 . 
         FIG. 11  is an illustration of the closure element according to one embodiment of the present invention, wherein the closure element is an annular band. 
         FIG. 12  is an illustration of the closure element according to another embodiment of the present invention, wherein the closure element is a U-shaped gripping clip. 
         FIG. 13A  is a top view of the closure element according to another embodiment of the present invention, wherein the closure element is a spiral clip. 
         FIG. 13B  is a perspective view of the spiral clip closure element illustrated in  FIG. 13A . 
         FIG. 14  is a perspective illustration of the closure element according to another embodiment of the present invention, wherein the closure element is a plug. 
         FIG. 15  is a perspective illustration of the closure element according to another embodiment of the present invention, wherein the closure element is a pronged staple. 
         FIG. 16  is a side view of a central tube of the arteriotomy closure system according to another embodiment of the present invention, wherein the central tube includes a ridge at the distal end for engaging and closing a pronged staple. 
         FIGS. 17-18  are partial longitudinal sectional views that illustrate, diagrammatically, the manner in which the central tube of  FIG. 16  may be used to engage and close a pronged staple. 
         FIG. 19  is a transverse cross-section illustrating the closure element disposed around the outer surface of the central tube according to one embodiment of the present invention. 
         FIG. 20  is a transverse cross-section illustrating the contracted tissue-gripping retention fingers having the closure element around the outer surface thereof according to another embodiment of the present invention. 
         FIG. 21  illustrates the distal portion of a modified central tube to form the tissue-gripping retention fingers according to one embodiment of the present invention. 
         FIG. 22  illustrates the distal portion of a modified central tube to form the tissue-gripping retention fingers according to another embodiment of the present invention. 
         FIG. 23  is a perspective illustration of an embodiment of the present invention including pull wires for expanding the tissue-gripping retention fingers. 
         FIG. 24  is a perspective illustration of another embodiment of the present invention including pull wires for expanding the tissue-gripping retention fingers. 
         FIG. 25  is a longitudinal sectional illustration of an arteriotomy closure system in accordance with the present invention, showing a control module at the proximal end for communicating suction to the distal end and for enabling advancement or withdrawal of the delivery tube with respect to the central tube. 
         FIGS. 26-29  illustrate the manner in which an arteriotomy closure system of the present invention may be used to approximate the edges of an arteriotomy by engaging and drawing together connective tissue associated with the vessel in which the arteriotomy is formed. 
         FIG. 30  is a sectional illustration of a central tube in accordance with the present invention used in association with a stabilizing system in engagement with the vessel. 
         FIG. 31  is a perspective illustration of another embodiment of a stabilizing system as may be used in connection with the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Specific embodiments of the present invention are now described with reference to the figures, wherein like reference numbers indicate identical or functionally similar elements. The terms “distal” and “proximal” are used in the following description with respect to a position or direction relative to the treating clinician. “Distal” or “distally” are a position distant from or in a direction away from the clinician. “Proximal” and “proximally” are a position near or in a direction toward the clinician. 
     The following detailed description is merely exemplary in nature and is not intended to limit the invention or the application and uses of the invention. Although the description of the invention is in the context of treatment of blood vessels such as the coronary, carotid and renal arteries, the invention may also be used in any other body passageways where it is deemed useful. Thus, the meaning of the term arteriotomy, as used for convenience throughout the specification and claims, should be taken to include openings in body passageways in addition to arteries, such as, by non-limiting example, a venipuncture into a vein. Furthermore, there is no intention to be bound by any expressed or implied theory presented in the preceding technical field, background, brief summary or the following detailed description. 
     Embodiments of the present invention relate to a device for delivering a closure element that closes an arterial puncture or arteriotomy. More particularly, a percutaneously placeable central tube is deployable about an arteriotomy by which an array of tissue grippers or fingers having suction ports can be engaged with the surface of tissue about the arteriotomy enabling the ports to grip the tissue without piercing it. The device may be advanced over an indwelling guidewire with the fingers in a radially contracted configuration. When the distal end of the device is located at the region of the arteriotomy, the fingers then may be deployed to a more radially expanded configuration about the region of the arteriotomy and, when in position, the gripping fingers may be actuated by applying suction to the suction ports to grip the tissue. With the fingers holding the tissue, the closure element can be distally advanced over the outer surface of the central tube to radially contract or collapse the fingers, thereby gathering, pursing, or puckering the tissue together to close the arteriotomy. The closure element is delivered to the site of the puckered arteriotomy by further distally advancing the closure element until it is released or forced over the distal tips of the fingers and surrounds the puckered tissue. The fingers then may be operated to release the tissue, as by terminating the suction, and the central tube and array of tissue fingers are withdrawn. The closure element remains in place to secure permanent closure of the arteriotomy. Since the closure element is advanced over the outer surface of the central tube, the central tube need only be of sufficient size to accommodate a conventional guidewire through a central lumen thereof and thus the overall profile of the delivery device can be minimized. 
     The closure element is advanced over the central tube by a delivery tube. In one embodiment, the delivery tube has a uniform or constant inner diameter along the length thereof. The inner diameter of the delivery tube is slightly larger than the outer diameter of the central tube in order to insure relative sliding motion between the delivery tube and the central tube. The closure element is pushed by the distal end of the delivery tube until it is released or forced off of the distal tips of the fingers and surrounds the puckered tissue. 
     In another embodiment, the delivery tube has a stepped inner diameter along the length thereof such that the distal portion of the delivery tube has a larger inner diameter than the proximal portion of the delivery tube. The closure element resides within the distal portion having a larger inner diameter such that the closure element is nested within the delivery tube during delivery. This “nested” embodiment ensures that the closure element is pushed over the fingers with minimal deformation and ensures that the closure element is protected during advancement. The closure element is pushed by the step of the inner diameter of the delivery tube until it is released or forced off of the distal tips of the fingers and surrounds the puckered tissue. 
     The closure element may take various forms, including an annular band, a spiral clip, a U-shaped clip, a plug with swelling potential, or a pronged staple. In one embodiment of the present invention, the closure element may be formed of a material having elastic properties in order to elastically grip the puckered tissue in order to secure permanent closure of the arteriotomy and to prevent slippage of the closure element. In another embodiment, the closure element may be formed from a material that plastically deforms in order to frictionally grip the puckered tissue about the arteriotomy and thereby prevent slippage of the closure element. Further details and description of the embodiments of the present invention are provided below with reference to  FIGS. 1-31 . 
       FIG. 1  illustrates the distal portion of a mechanism  10  incorporating the present invention, it being understood that the components of mechanism  10  that are movable along an axial direction (i.e., along a guidewire) extend to the proximal end of the system where they may be controlled to perform their respective functions and movements at the distal portion. Mechanism  10 , in this embodiment, is a delivery system for delivering a closure device to the site of an arteriotomy  30  of an artery  32 . Mechanism  10  includes a central tube  12  having a central lumen adapted to receive a guidewire  16 . Since the closure element is slid along the outside of central tube  12 , the central lumen therethrough need only be of sufficient size to accommodate guidewire  16 , and thus the overall profile, e.g., diameter, of mechanism  10  is lower than it would be if the closure element were delivered through the central lumen. For example, a conventional medical guidewire typically has a diameter of between approximately 0.012 inches and 0.038 inches, and thus the central lumen of central tube  12  need be only slightly larger than the size of the intended guidewire in order to insure relative sliding motion between guidewire  16  and central tube  12 . The distal portion of the central tube  12  carries radially expandable and contractible elements, such as tissue retention fingers  18  that may be formed integrally with central tube  12 . Fingers  18  have gripping elements, such as suction ports  20  (shown in  FIG. 2 ), at their distal ends. Suction ports  20  do not puncture tissue and are in communication with a source of suction (not shown) by suction lumens  22  extending proximally along central tube  12 . 
     Fingers  18  are movable between a radially contracted, low profile configuration (illustrated in  FIGS. 1 ,  2 ,  5 , and  6 ) and a radially expanded, deployed configuration (illustrated in  FIGS. 3 and 4 ) by a delivery tube  24  that is slidably disposed about an outer surface  11  of central tube  12 . As will be explained in more detail here, fingers  18  may be caused to deploy to a radially expanded configuration by forming them with a resilient bias toward the expanded configuration or by an arrangement of pull wires, or a combination of both. Fingers  18  may be caused to flare outwardly to engage the surface of tissue about arteriotomy  30  and suction then can be applied to cause fingers  18  to grip the adjacent tissue surface. Fingers  18  then are drawn radially inwardly to pucker the tissue surrounding arteriotomy  30  and hold it in that configuration until a more permanent closure element is delivered over outer surface  11  of central tube  12 . 
     More particularly, referring also to  FIGS. 4-6 , in addition to collapsing fingers  18  to a contracted configuration, delivery tube  24  also operates to push or force a closure element  100  over outer surface  11  of central tube  12  in order to deliver closure element  100  to the site of arteriotomy  30 . Delivery tube  24  extends to the proximal end of the device and can be advanced distally (in the direction of arrow  26 ) such that a distal end  23  of delivery tube  24  distally advances closure element  100 . Delivery tube  24  has a uniform or constant inner diameter along the length thereof. The inner diameter of delivery tube  24  is slightly larger than outer surface  11  of central tube  12  in order to permit relative sliding motion between delivery tube  24  and central tube  12 . As closure element  100  and delivery tube  24  pass over fingers  18 , fingers  18  radially contract or collapse, thereby puckering the tissue together and closing arteriotomy  30 . In some embodiments of the present invention, closure element  100  is elastic or otherwise variable in its radial dimensions, as will be described below. In at least these embodiments, it is the radial stiffness of delivery tube  24  that causes fingers  18  to contract as tube distal end  23  passes thereover. Closure element  100  is further advanced by distal end  23  of delivery tube  24  until it is pushed or forced off of distal tips  19  of fingers  18  and surrounds the puckered tissue. Closure element  100  secures permanent closure of arteriotomy  30  when central tube  12  and fingers  18  are withdrawn. 
       FIGS. 1-7  illustrate the manner or process in which mechanism  10  may be used to close an arteriotomy  30 . While arteriotomy  30  and artery  32  are illustrated in  FIG. 1 , they have been removed from  FIGS. 2-6  for clarity purposes. However, the description for utilizing mechanism  10  will describe the process for utilizing mechanism  10  in relation to arteriotomy  30 . Referring to  FIG. 1 , central tube  12  is advanced along an indwelling guidewire  16  with fingers  18  maintained in a contracted configuration to facilitate delivery of the device through a tissue track. In order to maintain fingers  18  in the contracted position, delivery tube  24  surrounds fingers  18 , and both the delivery tube and central tube  12  are advanced to the region of arteriotomy  30 . Once the distal end of the device is in proximity to the region of arteriotomy  30 , such as the tissue of the femoral sheath that surrounds artery  32 , delivery tube  24  may be withdrawn proximally (in the direction of arrow  28 ) as shown in  FIG. 2 . Proximally withdrawing delivery tube  24  allows fingers  18  to deploy to a radially expanded configuration as illustrated in  FIGS. 3 and 7 . 
     In one embodiment, delivery tube  24  is withdrawn proximally until the distal end  23  of the delivery tube  24  is released from central tube  12  and/or guidewire  16 . Once delivery tube  24  is removed, closure element  100  is positioned over outer surface  11  of central tube  12 . In addition, delivery tube  24  is also positioned over outer surface  11  of central tube  12  such that distal end  23  of delivery tube  24  is proximal to closure element  100 . Now referring to  FIG. 4 , delivery tube  24  is in position to be advanced distally (in the direction of arrow  26 ) in order to push closure element  100  distally along outer surface  11  of central tube  12 . It should be understood that it may not be required to withdraw delivery tube  24  until it is removed from central tube  12  but. In another embodiment, it is only required to proximally withdraw delivery tube  24  to a point at which closure element  100  may be mounted over outer surface  11  of central tube  12  at a position distal of delivery tube  24 . 
     In yet another embodiment, which appears as in the embodiment of  FIG. 5 , but without the movement indicated by arrow  26 , closure element  100  may be initially positioned, or pre-loaded, over fingers  18  distal to delivery tube  24 . In embodiments wherein fingers  18  are formed with a resilient bias toward the expanded configuration, proximally withdrawing delivery tube  24  allows the splaying or flaring action of fingers  18 , thereby forcing closure element  100  to slide in a proximal direction toward the bases of fingers  18 . Since delivery tube  24  is not directly withdrawing closure element  100 , low friction is required to permit closure element  100  to slide proximally along flared fingers  18  of central tube  12 . 
     Once fingers  18  radially expand, their distal ends are engaged with the tissue surface so that suction, applied through suction lumens  22 , will enable fingers  18  to grip the tissue surrounding arteriotomy  30 . It should be understood that approximation of arteriotomy  30  in the vessel wall does not necessarily require direct engagement with the vessel wall but, instead, may be accomplished by affecting a grip on the connective tissue, such as the femoral sheath, disposed about and connected to the outer surface of the vessel. 
     With reference to  FIG. 5 , delivery tube  24  is advanced distally over central tube  12 , pushing closure element  100  with distal end  23  of delivery tube  24 . As delivery tube  24  passes over fingers  18 , fingers  18  radially collapse inwardly, as indicated by arrows  34  in  FIG. 7 , into the contracted configuration. With the tissue about arteriotomy  30  gripped by fingers  18  via suction, radially collapsing fingers  18  also draws the tissue radially inward. The tissue about arteriotomy  30  becomes puckered toward a closed configuration suggested in phantom  36  at  FIG. 7 , thereby closing arteriotomy  30 . While retaining the tissue in that configuration, guidewire  16  then may be removed. As shown in  FIG. 6 , closure element  100  is distally advanced by delivery tube  24  until it is pushed off of distal finger tips  19  such that closure element  100  surrounds the puckered tissue. Then, the suction is terminated so that fingers  18  release the gripped tissue, and central tube  12  and delivery tube  24  are withdrawn. Closure element  100  remains implanted around the puckered tissue in order to secure permanent closure of arteriotomy  30 . 
     In another embodiment of the present invention illustrated in  FIG. 8 , a protective sheath  809  may be provided to surround delivery tube  24  as it is advanced over central tube  12  in order to facilitate tracking of closure element  100  along a tissue track to the site of the arteriotomy. In addition, protective sheath  809  may be utilized to maintain fingers  18  in the contracted position while delivery tube  24 , closure element  100 , and central tube  12  are tracked to the region of the arteriotomy. If such protective sheath  809  is used to maintain fingers  18  in the contracted position, it is not required to proximally withdraw delivery tube  24  to a point at which closure element  100  may be placed over outer surface  11  of central tube  12  distal of delivery tube  24  as described above. Rather, closure element  100  and delivery tube  24  are initially positioned, or pre-loaded, over outer surface  11  of central tube  12  proximal to fingers  18 . Protective sheath  809  surrounds delivery tube  24 , closure element  100 , and central tube  12  and maintains fingers  18  in the contracted position. After the entire system reaches the region of the arteriotomy, protective sheath  809  is retracted proximally in the direction of arrow  28  in order to allow fingers  18  to deploy to the radially expanded configuration. While in the radially expanded configuration, suction is applied to cause fingers  18  to grip the adjacent tissue surface. Delivery tube  24  may then be advanced distally in order to push closure element  100  over fingers  18 , and simultaneously collapsing fingers  18  radially inwardly into the contracted configuration, thus puckering the tissue about the arteriotomy. Continued advancement of delivery tube  24  results in closure element  100  being pushed off of distal finger tips  19  and around the puckered tissue. 
       FIGS. 9 and 10  illustrate another embodiment of the delivery tube having a stepped inner diameter along the length thereof. More particularly, delivery tube  924  includes a proximal portion  921  having an inner diameter D 1  and a distal portion  925  having an inner diameter D 2 . Inner diameter D 1  of delivery tube  924  is slightly larger than outer surface  11  of central tube  12  in order to permit delivery tube  924  to slide over central tube  12 . Inner diameter D 2  of distal portion  925  is larger than inner diameter D 1  of proximal portion  921 . A step  927  is formed where the inner diameter of delivery tube  924  increases from inner diameter D 1  to inner diameter D 2 . Delivery tube  924  is shown as having a uniform outside diameter and a corresponding change in wall thickness occurring at step  927 . In an alternative embodiment (not shown), delivery tube  924  may have a change in outside diameter occurring at step  927 . Step  927  is used to push the closure element over the distal tips of the fingers. As shown in  FIG. 10 , closure element  100  is nested within distal portion  925  of delivery tube  924  during delivery. This “nested” embodiment ensures that closure element  100  is pushed over central tube  12  with minimal deformation of the closure element, and ensures that closure element  100  is protected from contact with objects or tissue along the tissue track during advancement to the region of the arteriotomy. 
     In addition, distal portion  925  of delivery tube  924  maintains fingers  18  in the contracted position while delivery tube  924 , closure element  100 , and central tube  12  are tracked to the region of the arteriotomy. If this “nested” embodiment is used to maintain fingers  18  in the contracted position, it is not required to proximally withdraw the delivery tube to a point at which the closure element may be placed over the outer surface of the central tube distal of the delivery tube as described above. Rather, closure element  100  and delivery tube  924  are pre-loaded onto central tube  12  with distal portion  925  and closure element  100  positioned around fingers  18 , thus maintaining fingers  18  in the contracted position. After the entire system reaches the region of the arteriotomy, delivery tube  924  is retracted proximally in the direction of arrow  28  in order to allow fingers  18  to deploy to the radially expanded configuration. As described above, proximally withdrawing delivery tube  924  allows the splaying or flaring action of fingers  18 , thereby forcing closure element  100  to slide in a proximal direction toward the bases of fingers  18 . While in the radially expanded configuration, suction is applied to cause fingers  18  to grip the adjacent tissue surface. Delivery tube  924  may then be advanced distally such that step  927  of the inner diameter of delivery tube  924  pushes closure element  100  over fingers  18 , radially collapsing them inwardly into the contracted configuration and puckering the tissue, until closure element  100  is forced off of finger tips  19  and around the puckered tissue. In this embodiment, delivery tube  924  is advanced distally to a point where step  927  is distally past fingertips  19 . 
     The closure element for securing permanent closure of the arteriotomy may assume various forms. For example, the closure element may be an annular band  1101  as shown in  FIG. 11 . In one embodiment, annular band  1101  is constructed from an elastic material that is stretched over outer surface  11  of central tube  12  so that when it is pushed off finger tips  19 , annular band  1101  contracts around the puckered tissue of an arteriotomy. In other words, due to elastomeric properties, band  1101  seals and compresses tissue around the arteriotomy. Annular band  1101  may be a ring of elastomer with a rectangular, round or  0 -shaped cross-section. For example, annular band  1101  may be formed from a type of biocompatible elastomer, including synthetic rubbers such as silicone or thermoplastic elastomers such as polyurethanes or polyamides. In one embodiment, the closure element may be formed from a bioabsorbable or biodegradable material that is selected to be absorbed or degraded in vivo over time. Annular band  1101  elastically grips the puckered tissue in order to secure permanent closure of the arteriotomy and thereby prevent slippage annular band  1101 . 
     Another embodiment of the closure element is depicted in  FIG. 12 , wherein the closure element is a gripping clip  1202  having a generally U-shaped configuration. The inner surface of gripping clip  1202  includes teeth  1203  for gripping the puckered tissue about the arteriotomy. Alternatively, the inner surface  1202  may have other protrusions or be otherwise jagged or raised in order to grip the puckered tissue about the arteriotomy and thereby prevent slippage of gripping clip  1202 . 
     Gripping clip  1202  may be formed of a material having resilient properties in order to grip the puckered tissue in order to secure permanent closure of the arteriotomy and further prevent slippage of gripping clip  1202 . Biocompatible metals suitable for use in gripping clip  1202  include stainless steel  316 L, stainless steel  316  LVM, titanium, nickel-titanium (nitinol) or bioabsorbable magnesium, which is absorbed by a patient&#39;s body as the arteriotomy into which gripping clip  1202  is inserted heals. Biocompatible non-resorbable polymeric materials suitable for use in gripping clip  1202  may include polymethylmethacrylate (PMMA), high density polyethylene (HDPE), and ultra high molecular weight polyethylene (UHMWPE). Gripping clip  1202  may also be made of an implant grade bioabsorbable polymer material such that gripping clip  1202  is absorbed by a patient&#39;s body as the arteriotomy around which gripping clip  1202  is inserted heals. For example, and not by way of limitation, gripping clip  1202  may be made from polyglycolic acid (PGA), polylactic acid (PLA), alloys or blends of PGA and PLA, alloys or blends of PGA and tri-methyl carbonate, and alloys or blends of PLA and tri-methyl carbonate. Gripping clip  1202  having sufficiently elastic properties may be stretched over the outer surface  11  of central tube  12  so that when it is released or pushed off the finger tips  19 , it contracts around the puckered tissue of an arteriotomy. 
     Another embodiment of the closure element is depicted in  FIGS. 13A and 13B , wherein the closure element is a coil spring or spiral clip  1304  having multiple loops or turns extending between a first end  1305  and a second end  1306 . In one embodiment, spiral clip  1304  is constructed from an elastic material that is radially stretched over the outer surface  11  of central tube  12  so that when it is released or pushed off finger tips  19 , spiral clip  1304  radially contracts around the puckered tissue of an arteriotomy. Spiral clip  1304  may be formed from any of the materials described above regarding gripping clip  1202 . Spiral clip  1304  elastically grips the puckered tissue in order to secure permanent closure of the arteriotomy and thereby prevent slippage of spiral clip  1304 . 
     Another embodiment of the closure element is depicted in  FIG. 14 , wherein the closure element is a plug  1407 . Plug  1407  is constructed out of a hydrogel, collagen, or a bioabsorbable polymer having swelling potential such that when it is released or pushed off finger tips  19 , plug  1407  swells around the puckered tissue and plugs the tissue track adjacent the arteriotomy, thereby securing permanent closure of the arteriotomy. In one embodiment, the hydrogel, collagen, or bioabsorbable polymer material may be freeze-dried or dehydrated. Plug  1407  includes a central passageway or hole  1408  extending there through so that plug  1407  may be delivered over outer surface  11  of central tube  12 . Central passageway or hole  1408  will swell shut after plug  1407  is released from central tube  12 . 
     Another embodiment of the closure element is depicted in  FIG. 15 , wherein the closure element is a staple  1590 . Staple  1590  may be similar to one of the staples, for example, of the type described in U.S. Pat. No. 6,767,356 (Kanner). Reference is made to the Kanner &#39;356 patent for additional details concerning various constructions and embodiments of the staple closure element, which are incorporated by reference herein, in their entirety. 
     Staple  1590  is delivered over a central tube  1612 , shown in  FIG. 16 . Central tube  1612  includes at least one ridge or protrusion  1662  about outer surface  11  proximal to fingers  18 . Ridge  1662  closes prongs  1594  of staple  1590  about the arteriotomy. Ridge  1662  is provided circumferentially about outer surface  11  and may be continuous or non-continuous. Ridge  1662  has a greater outer diameter D 4  than diameter D 3  of outer surface  11  of central tube  1612  for engaging and subsequently closing staple  1590 . 
       FIGS. 17 and 18  illustrate delivery of staple  1590  using central tube  1612  and delivery tube  24 . Staple  1590  is mounted about central tube  1612  with prongs  1594  pointing distally and extending across ridge  1662 , as shown in  FIG. 17 . Fingers  18  are splayed for engagement with tissue, as described regarding other embodiments herein. As delivery tube  24  is advanced to push staple  1590  distally along central tube  1612 , prongs  1594  contract fingers  18  and pucker tissue surrounding the arteriotomy. Staple tips  1595  are slid over finger tips  19  to pierce the puckered tissue. Further advancement of staple  1590  by delivery tube  24  forces staple base portions  1598  to radially expand over ridge  1662 , thus causing staple prongs  1594  to pivot such that staple tips  1595  contract radially inwards towards each other, as shown in  FIG. 18 . Staple  1590  remains plastically deformed and embedded around the puckered tissue in order to secure permanent closure of the arteriotomy. 
     As previously stated, fingers  18  may be moved between a radially contracted, low profile configuration ( FIGS. 1 ,  2 ,  5 , and  6 ) and a radially expanded, deployed configuration ( FIGS. 3 and 4 ) by delivery tube  24  that is slidably disposed about central tube  12 . Fingers  18  may move in a generally radial pattern with or without symmetry about a central point, such as a central location of the arteriotomy. Alternatively, some or all of fingers  18  may be adapted to expand and contract in a pattern having line symmetry (not shown). Thus, the terms “radial” or “radially” are not intended herein to be limited strictly to the radii of a circle when such terms are used to describe the movement of fingers  18 . 
       FIG. 19  illustrates one mode of construction for causing fingers  18  to deploy to a radially expanded configuration in which fingers  18  are formed with a resilient bias toward the expanded configuration. More particularly, central tube  12  may be a suitably flexible, extruded biocompatible plastic having suction lumens  40  extending through the wall of tube  12 . Fingers  18  may be formed integrally with tube  12 . Smaller suction tubes  42 , formed from a material having sufficient elasticity and resilience may be contained within lumens  40  to communicate the suction to suction ports  20  and to assist in biasing fingers  18  in their radially outward, splayed configuration. Suction tubes  42  may, for example, be formed from nitinol (NiTi) hypotubes that may extend within the extruded lumens  40  in the wall of central tube  12 . The nitinol hypotubes may be heat set to a preformed shape (bent radially outward) so that they will bias fingers  18  to the outward position of  FIGS. 3 and 4 . It should be understood that other resilient spring elements may be incorporated into or associated with fingers  18  to bias them toward a radially outward configuration. Fingers  18  may be contracted from the splayed to the contracted configuration by advancing delivery tube  24  distally, sliding it along outer surface  11  of central tube  12  as described in more detail above. As delivery tube  24  is advanced distally, it overcomes the bias of the nitinol hypotubes so that continued advancement of delivery tube  24  draws fingers  18  together. The nitinol hypotubes should enhance the ability for suction to be maintained at the suction outlets throughout such range of movement. 
       FIG. 20  illustrates another embodiment for causing fingers  18  to deploy to a radially expanded configuration in which central tube  12 A is formed entirely from a shape memory alloy such as nitinol with fingers  18 A being heat set to be biased in the radially expanded, splayed configuration when at normal human body temperature. Suction lumens  40 A may be formed longitudinally through the wall of the tube by wire electrical discharge machining (EDM). For example, using a 0.031 inch EDM electrode would enable fabrication of a finished hole of the order of 0.035 inch in the tube wall with a depth of up to about six inches. Should it be necessary to make the device longer, additional tubes could be fabricated and joined end-to-end with suction lumens  40 A aligned. The tube may, for example, be of the order of about 0.23 inch diameter with a wall thickness of about 0.072 inch and an inner diameter of about 0.09 inch. The distal portion of nitinol central tube  12 A may be formed similarly to the above-described embodiments such that the plurality of fingers  18 A each include suction ports at or about the distal ends of fingers  18 A. The nitinol should be treated so that fingers  18 A are biased to the radially expanded configuration yet are elastically returnable to the non-expanded configuration by advancement of delivery tube  24 . 
     As will be apparent to those skilled in the art, suction ports  20  of fingers  18  may be located in various configurations.  FIGS. 2 ,  3 , and  7  show suction ports  20  located on the distal end faces of fingers  18 . It may be desirable, in some cases, to locate the suction ports at other locations for contacting tissue surrounding the arteriotomy. For example, in one embodiment of the present invention shown in  FIG. 21 , suction ports  20 A may be located on the outer faces of fingers  18 . In another embodiment of the present invention shown in  FIG. 22 , the distal end of central tube  12  is beveled at bevel  13 . The angle of bevel  13  may be selected to correspond to the approach angle (approximately 45°) of the device to the vessel. Suction ports  20 B also may be aligned along bevel  13 . 
       FIG. 23  illustrates an embodiment of the invention including an arrangement of pull wires for deploying fingers  18 . In this embodiment, fingers  18  are radially expanded by pull wires such as filaments  44  secured to the outer ends of the fingers  18 . In one embodiment shown in  FIG. 23 , filaments  44  may extend through apertures  46  located in central tube  12  and may extend proximally to a control point at the proximal end of the system. Apertures  46  should be located as to not interfere with suction lumens  22  extending through the wall of central tube  12 . During delivery, fingers  18  should be in the contracted, low profile configuration, with or without the assistance of delivery tube  24 . Once the device is located in the region of the arteriotomy, pulling on filaments  44  cause fingers  18  to pivot or flex about their roots. After suction is applied such that fingers  18  grip the tissue surrounding the arteriotomy, fingers  18  may be returned to a contracted configuration by releasing tension on filaments  44  and advancing delivery tube  24  and closure element  100  in a distal direction over outer surface  11  of central tube  12  as described above with respect to  FIGS. 4-6 . Closure element  100  is pushed or forced over filaments  44  and fingers  18  and is pushed off of distal tips  19  in order to permanently close the arteriotomy as described above. Filaments  44  may be of a fine diameter of the order of about 0.0015 to about 0.005 inch, and may be formed from polymers such as polypropylene, polyethylene terephthalate or nylon or from metals such as nitinol, nickel-cobalt-chromium-molybdenum superalloy, stainless steel or the like. Filaments  44  may be attached to fingers  18  by knotting, laser welding or other appropriate means for attachment as will be familiar to those skilled in the art. 
       FIG. 24  illustrates another embodiment of the invention including an arrangement of pull wires for deploying fingers  18 . In the embodiment of  FIG. 24 , filaments  44 A may be secured directly to a pull wire sheath  48  at attachment points  47 . Pull wire sheath  48  is slidably located over outer surface  11  of central tube  12  and may extend proximally to a control point at the proximal end of the system. During delivery, fingers  18  should be in the contracted, low profile configuration by distally advancing pull wire sheath  48  over fingers  18 . Once the device is located in the region of the arteriotomy, retraction of pull wire sheath  48  will tension filaments  44 A to expand fingers  18  as shown in  FIG. 24 . After suction is applied such that fingers  18  grip the tissue surrounding the arteriotomy, fingers  18  may be returned to a contracted configuration by distally advancing pull wire sheath  48 . Distally advancing pull wire sheath  48  pushes or forces fingers  18  into the contracted configuration. In another embodiment in which fingers  18  are formed resiliently biased to the contracted configuration, distally advancing pull wire sheath  48  merely releases tension in filaments  44 A to allow fingers  18  to close. Alternatively (not shown), fingers  18  may be returned to a contracted configuration by distally advancing delivery tube  24  and closure element  100  over outer surface  49  of pull wire sheath  48  and over filaments  44 A. Regardless of how fingers  18  are closed (via distal advancement of pull wire sheath  48  or delivery tube  24 ), delivery tube  24  and closure element  100  are then advanced in a distal direction over an outer surface  49  of pull wire sheath  48  in order to push or force closure element  100  off the distal end of the device to permanently close the arteriotomy. Filaments  44 A may be of a fine diameter of the order of about 0.0015 to about 0.005 inch, and may be formed from polymers such as polypropylene, polyethylene terephthalate or nylon or from metals such as nitinol, nickel-cobalt-chromium-molybdenum superalloy, stainless steel or the like. In addition, filaments  44 A may be attached to fingers  18  and pull wire sheath  48  by knotting, laser welding or other appropriate means for attachment as will be familiar to those skilled in the art. 
     If an arrangement of pull wires such as those described above with reference to  FIGS. 23-24  is used to maintain fingers  18  in the contracted position, it is not required to proximally withdraw delivery tube  24  to a point at which closure element  100  may be placed over outer surface  11  of central tube  12  distal of delivery tube  24 . Since retraction of delivery tube  24  is not required for causing deployment of fingers  18 , closure element  100  and delivery tube  24  may initially be positioned, or pre-loaded, over outer surface  11  of central tube  12  proximal to fingers  18 . After the pull wire arrangement is utilized for deploying fingers  18  to the radially expanded configuration, delivery tube  24  and closure element  100  are then advanced in a distal direction in order to push or force closure element  100  off the distal end of the device to permanently close the arteriotomy. 
       FIG. 25  illustrates one arrangement at the proximal end of the device by which the device may be controlled. The proximal end of the device may include a sealed housing  50  secured to the proximal end of delivery tube  24 . Housing  50  includes a suction port  52  that is connectible to a source of suction (not shown). Central tube  12  extends through a slidably sealed opening  54  in housing  50  and includes a proximally extending extension tube  56  adapted to receive a guidewire. The device also includes a manifold  58  that is secured to the proximal end of central tube  12 . Manifold  58  is in fluid communication with the proximal ends of suction lumens  22  in central tube  12 . When located within housing  50 , manifold  58  also is in fluid communication with the interior of housing  50  by one or more ports  60  so that when suction is applied to allow fingers  18  to grip the tissue surrounding the arteriotomy, the suction will be communicated from housing  50  to distal suction ports  20  through suction lumens  22 . Housing  50  and delivery tube  24  thus are movable together with respect to central tube  12  and manifold  58  in order to deliver closure element  100  over the distal end of the device, and also in order to expand and/or collapse the fingers at the distal end of the device. 
       FIGS. 26-29  illustrate, diagrammatically, the manner in which the device may cause approximation of the edges of the arteriotomy without directly engaging the vessel wall. As shown on  FIG. 26 , after the vascular procedure has been completed, guidewire  16  is placed (or left in place) through a tissue track  70  and into a vessel  76  and the introducer (not shown) then is withdrawn. Tissue track  70  extends through skin  72 , subcutaneous and connective tissue  74 , including fascia and the femoral sheath which are attached to the outer adventitia of vessel  76 .  FIG. 27  illustrates the distal portion of the device advanced along indwelling guidewire  16  through tissue track  70  as it approaches connective tissue  74  disposed about the region of an arteriotomy  78 . Delivery tube  24  is positioned over outer surface  11  of central tube  12  in order to maintain fingers  18  in the contracted or collapsed configuration. When the device is positioned proximally of an arteriotomy  78 , delivery tube  24  is retracted to enable or cause the fingers to be deployed radially outward into engagement with connective tissue  74  about and proximally of the puncture in the vessel wall as shown in  FIG. 28 . Suction then is applied to cause connective tissue  74  to be drawn securely against the suction ports. The connection between connective tissue  74  and the wall of vessel  76  is such that connective tissue  74  can be drawn while maintaining its attachment to the vessel wall. 
     As previously explained with relation to  FIGS. 3-4 , it may be required to proximally withdraw delivery tube  24  until the distal end thereof is released from central tube  12  and/or guidewire  16 . If so required, delivery tube  24  is removed and closure element  100  is positioned over the proximal end of outer surface  11  of central tube  12 . In addition, delivery tube  24  is also positioned over the proximal end of outer surface  11  of central tube  12 , proximal to closure element  100 . Delivery tube  24  is advanced distally in order to push or force closure element  100  over outer surface  11  of central tube  12 . As delivery tube  24  and closure element  100  are advanced over fingers  18 , fingers  18  radially collapse inwardly into the contracted configuration such that the connective tissue  74  gripped by fingers  18  will also be drawn together and that, in turn, draws edges  80  of arteriotomy  78  toward each other by reason of the connection between connective tissue  74  and the wall of vessel  76  (see  FIG. 29 ). With connective tissue  74  so held by the device, guidewire  16  may be withdrawn and closure element  100  is distally advanced by delivery tube  24  until it is pushed or forced over or past the distal tips of fingers  18  such that closure element  100  engages the puckered connective tissue  74  as illustrated in  FIG. 29 . The suction or aspiration force is terminated so that fingers  18  release connective tissue  74 , and central tube  12  and delivery tube  24  are withdrawn. Closure element  100  remains around the puckered connective tissue  74  in order to secure permanent closure of arteriotomy  78 . After removal of the delivery device, a short duration of external pressure may be desirable as a precaution. 
     The invention also may be practiced in conjunction with a stabilizing device, for example, of the type described in U.S. Pat. No. 6,767,356 (Kanner). As shown in  FIG. 30 , wire-like stabilizers  82  may extend through central tube  12 . The distal ends of stabilizers  82  are configured to be placed through arteriotomy  78  into the lumen of vessel  84 . Stabilizers  82 , which are inserted in a linear configuration, then are operated to an enlarged configuration, as illustrated in  FIGS. 30  or  31 , so that they cannot be withdrawn through arteriotomy  78 . Stabilizers  82  thus provide a stable platform with which central tube  12  can be held in centered position over the region of the arteriotomy. Stabilizers  82  may include a guide  86  that may be secured to tube  12  and through which stabilizer  82  may be advanced or retracted when in its linear, non-deployed configuration. Reference is made to the Kanner &#39;356 patent for additional details concerning various constructions and embodiments of the stabilizing system, which are incorporated by reference herein, in their entirety. 
     While various embodiments according to the present invention have been described above, it should be understood that they have been presented by way of illustration and example only, and not limitation. It will be apparent to persons skilled in the relevant art that various changes in form and detail can be made therein without departing from the spirit and scope of the invention. Thus, the breadth and scope of the present invention should not be limited by any of the above-described exemplary embodiments, but should be defined only in accordance with the appended claims and their equivalents. It will also be understood that each feature of each embodiment discussed herein, and of each reference cited herein, can be used in combination with the features of any other embodiment. All patents and publications discussed herein are incorporated by reference herein in their entirety.