Abstract:
A device for suturing an opening in a tissue, having an elongated shaft, at least two arms movable to a deployed positioning which the arms are non-perpendicular to the shaft, the arms having needle receiving portions; and needles advanceable longitudinally along the shaft toward the needle receiving portions, the needles exiting through side walls of the shaft at a location proximal to the arms.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention relates generally to apparatus and methods for the suturing of body lumens. More particularly, the present invention relates to techniques for percutaneous closure of arterial and venous puncture sites, which are usually accessed through a tissue tract. 
         [0003]    A number of diagnostic and interventional vascular procedures are now performed translumenally. A catheter is introduced to the vascular system at a convenient access location and guided through the vascular system to a target location using established techniques. Such procedures require vascular access, which is usually established during the well-known Seldinger technique, as described, for example, in William Grossman&#39;s “Cardiac Catheterization and Angioplasty,” 3.sup.rd Ed., Lea and Febiger, Philadelphia, 1986, incorporated herein by reference. Vascular access is generally provided through an introducer sheath, which is positioned to extend from outside the patient body into the vascular lumen. 
         [0004]    When vascular access is no longer required, the introducer sheath is removed and bleeding at the puncture site stopped. One common approach for providing hemostasis (the cessation of bleeding) is to apply external force near and upstream from the puncture site, typically by manual or “digital” compression. This approach suffers from a number of disadvantages. It is time consuming, frequently requiring one-half hour or more of compression before hemostasis is assured. Additionally, such compression techniques rely on clot formation, which can be delayed until anticoagulants used in vascular therapy procedures (such as for heart attacks, stent deployment, non-optical PTCA results, and the like) wear off. This can take two to four hours, thereby increasing the time required before completion of the compression technique. The compression procedure is further uncomfortable for the patient and frequently requires analgesics to be tolerable. Moreover, the application of excessive pressure can at times totally occlude the underlying blood vessel, resulting in ischemia and/or thrombosis. Following manual compression, the patient typically remains recumbent from four to as much as twelve hours or more under close observation so as to assure continued hemostasis. During this time renewed bleeding may occur, resulting in blood loss through the tract, hematoma and/or pseudoaneurysm formation, as well as arteriovenous fistula formation. These complications may require blood transfusion and/or surgical intervention. 
         [0005]    The incidence of complications from compression-induced hemostasis increases when the size of the introducer sheath grows larger, and/or when the patient is anticoagulated. It is clear that the compression technique for arterial closure can be risky, and is expensive and onerous to the patient. Although the risk of complications can be reduced by using highly trained individuals, dedicating such personnel to this task is both expensive and inefficient. Nonetheless, as the number and efficacy of translumenally performed diagnostic and interventional vascular procedures increases, the number of patients requiring effective hemostasis for a vascular puncture continues to increase. 
         [0006]    To overcome the problems associated with manual compression, the use of bioabsorbable fasteners or sealing bodies to stop bleeding has previously been proposed. Generally, these approaches rely on the placement of a thrombogenic and bioabsorbable material, such as collagen, at the superficial arterial wall over the puncture site. While potentially effective, this approach suffers from a number of problems. It can be difficult to properly locate the interface of the overlying tissue and the adventitial surface of the blood vessel. Locating the fastener too far from that interface can result in failure to provide hemostasis, and subsequent hematoma and/or pseudo-aneurysm formation. Conversely, if the sealing body intrudes into the arterial lumen, intravascular clots and/or collagen pieces with thrombus attached can form and embolize downstream, causing vascular occlusion. Also, thrombus formation on the surface of a sealing body protruding into the lumen can cause a stenosis, which can obstruct normal blood flow. Other possible complications include infection, as well as adverse reaction to the collagen or other implant. 
         [0007]    A more effective approach for vascular closure has been proposed in U.S. Pat. Nos. 5,417,699, 5,613,974; and PCT published Patent Application No. PCT/US96/10271 filed on Jun. 12, 1996, the full disclosures of which are incorporated herein by reference. A suture-applying device is introduced through the tissue tract with a distal end of the device extending through the vascular puncture. One or more needles in the device are then used to draw suture through the blood vessel wall on opposite sides of the puncture, and the suture is secured directly over the adventitial surface of the blood vessel wall to provide highly reliable closure. 
         [0008]    While a significant improvement over the use of manual pressure, clamps, and collagen plugs, certain design criteria have been found to be important to successful suturing to achieve vascular closure. For example, it is highly beneficial to properly direct the needles through the blood vessel wall at a significant distance from the puncture so that the suture is well anchored in the tissue and can provide tight closure. It is also highly beneficial to insure that the needle deployment takes place when the device is properly positioned relative to the vessel wall. The ease of deployment and efficacy of the procedure can further be enhanced by reducing the cross-section of that portion of the device, which is inserted into the tissue tract and/or the vessel itself, which may also allow closure of the vessel in a relatively short amount of time without imposing excessive injury to the tissue tract or vessel. 
         [0009]    For the above reasons, it would be desirable to provide improved devices, systems, and methods for suturing vascular punctures. The new device should have the capability of delivering a pre-tied knot to an incision site. It would be particularly beneficial if these improved devices provided some or all of the benefits while overcoming one or more of the disadvantages discussed above. 
         [0010]    2. Description of the Background Art 
         [0011]    U.S. Pat. Nos. 5,700,273, 5,836,956, and 5,846,253 describe a wound closure apparatus and method in which needles are threaded with suture inside a blood vessel. U.S. Pat. No. 5,496,332 describes a wound closure apparatus and method for its use, while U.S. Pat. No. 5,364,408 describes an endoscopic suture system. 
         [0012]    U.S. Pat. No. 5,374,275 describes a surgical suturing device and method of use, while U.S. Pat. No. 5,417,699 describes a device and method for the percutaneous suturing of a vascular puncture site. An instrument for closing trocar puncture wounds is described in U.S. Pat. No. 5,470,338, and a related device is described in U.S. Pat. No. 5,527,321. U.S. Pat. No. 5,507,757 also describes a method of closing puncture wounds. 
         [0013]    U.S. Pat. No. 6,245,079, describes another suturing system, the complete disclosure of which is incorporated herein by reference in its entirety for all purposes. 
       SUMMARY OF THE INVENTION 
       [0014]    The present invention provides a device for suturing an opening in a tissue. In various embodiments, the device includes an elongated shaft with a pair of deployable arms. When deployed, these arms are non-perpendicular to the longitudinal axis of the shaft. In one embodiment, the arms are independently deployable. In one embodiment, a first arm is an anterior arm which is deployed by being rotated less than 90 degrees to the longitudinal axis of the shaft, and the second arm is a posterior arm which is deployed by being rotated more than 90 degrees to the longitudinal axis of the shaft. A pivot stop may be provided on the elongated shaft to limit rotation of the arms when they reach their fully deployed position. Each of the first and second arms may include a needle receiving portion thereon. Needles may be advanced longitudinally along the shaft toward the needle receiving portions on the arms. The needles may exit through a side wall of the shaft at a location proximal to the arms. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0015]      FIG. 1  is a cross-sectional view of a suturing system with its distal end inserted through an arterial wall. ( FIG. 1  corresponds to FIG. 41 of U.S. Pat. No. 6,245,079). 
           [0016]      FIG. 2  is a cross-sectional view of the device of  FIG. 41  in a partially deployed state. ( FIG. 2  corresponds to FIG. 42 of U.S. Pat. No. 6,245,079). 
           [0017]      FIG. 3  is cross-sectional view of the device of  FIG. 1  with the suture clasp member fully deployed. ( FIG. 3  corresponds to FIG. 47 of U.S. Pat. No. 6,245,079). 
           [0018]      FIG. 4A  is a front plan view of the present invention in its compact position (i.e. prior to deployment). 
           [0019]      FIG. 4B  is a left side elevation view of the present invention prior to deployment. 
           [0020]      FIG. 5A  is a front plan view of the present invention after deployment. 
           [0021]      FIG. 5B  is a right side elevation view of the present invention after deployment. 
           [0022]      FIG. 6  is an illustration of the system of  FIG. 5B  deployed at a non-perpendicular angle relative to the axis of a blood vessel while the first and second arms  610  and  620  are positioned longitudinally along the inside of the wall of blood vessel. 
           [0023]      FIG. 7  is an embodiment of the present split arm invention, incorporating a pre-tied knot. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0024]      FIGS. 1 ,  2  and  3  show a suturing device corresponding to the suturing device described in U.S. Pat. No. 6,245,079, the complete disclosure of which is incorporated herein by reference in its entirety for all purposes. Specifically,  FIGS. 1 ,  2 , and  3  correspond to FIGS. 41, 42 and 47 of U.S. Pat. No. 6,245,079. 
         [0025]    Referring to  FIG. 1 , distal portion of the suturing device  520  is positioned in femoral artery  16 . Suturing device  520  comprises a suture introducer head  522  attached to the distal end of a hollow elongated body  514 . Suture clasp member  500  and the needles  546  reside in the same longitudinal space. In other words, the needles  546  share the same housing as the suture clasp member  500  (while they are all in their retracted state), but are higher up (proximally) in the suturing device  520  than the suture clasp member  500 . Flexible needles  546  bend outward, away from the axis of the device  520 , when in the extended position (as shown in  FIG. 3 ). 
         [0026]    As shown in  FIGS. 2 and 3 , the suture introducer head  522  has two needle ports or apertures  510  formed therein (one per needle  546 ) proximal to the suture clasp arms  524 . Each needle port includes a needle guiding portion  512  (“needle guide”), in the form of an outwardly curved groove or channel, which guides the corresponding needle  546  along a particular path. The needle guides  512  may be formed within the suture introducer head  522  (as shown in  FIG. 1 ) as part of a mold, or may be separate pieces (not shown) that are inserted into the suture introducer head  522  during manufacture. 
         [0027]    Bleed back is accomplished by the hole  540  at the distal end  504  of the suture introducer head  522 , the suture clasp arm apertures  508  and any other openings in the suture introducer head  522 . The direction of blood flow for bleed back is shown by the dashed arrows in  FIG. 1 . 
         [0028]    Suture  40  closes the artery vessel opening  26  transverse to the flow of blood. Proper insertion of the needles  546  reduces the risk of damage to the vessel walls  22 ,  506 . 
         [0029]    Suturing device  520  includes a single, resilient suture clasp member  500  attached to the actuating rod  50 . The suture clasp member  500  comprises a center or hinge portion  542  and two suture clasp arms  524  (one for each needle  546 ). Each suture clasp arm  524  has a suture clasp  544  at the end thereof. 
         [0030]    The hinge portion  542  of the suture clasp member  500  acts as a “living hinge” because it has a memory which causes the member  500  to return to a partially open, unretracted position ( FIG. 2 ) when a force (applied via rod  50 ) is released. This can be seen in  FIGS. 1 and 2 . In  FIG. 2 , the suture clasp member  500  is deployed in the artery  16  in its predisposed (relaxed or natural) position. In  FIG. 1 , the suture clasp member  500  is retracted into the suture introducer head  522  in its compressed (stressed or tensed) position. The arms  524  are moved to the retracted position by applying a distal force to the actuator rod  50 , which causes the arms to contact deflection surfaces  518  ( FIG. 2 ). 
         [0031]    This suture clasp member  500  is preferably composed of a resilient shape memory material such as NITENOL, but may alternatively be composed of another material with spring-like characteristics, such as plastic, spring steel, stainless steel or any variations thereof. Further, the suture clasp member  500  could be composed of two arms that are hingedly connected to the actuating rod  50  without the use of a resilient hinge. 
         [0032]    Needles  546  are flexible and preferably made from a material with shape memory, such as SUPERFLEX NITENOL. Alternatively, the needles  546  may be composed of spring steel, surgical stainless steel or any variation thereof. 
         [0033]    When the needles  546  are advanced distally and come in contact with the needle insertion guides  512 , the needle insertion guides cause the needles  546  to bend radially outward. The needles  546  also preferably further bend slightly (radially outward) when they come in contact with the angled surfaces  545  of the suture clasp arms  524 , as shown in  FIG. 3 . When the needles  546  are retracted into the needle lumens  516 , they resume a straight configuration as a result of their resiliency. 
         [0034]    The proximal portion of the suturing device  520  preferably includes a handle which allows the physician to externally operate the suture clasp arms  524  and the needles  546  inside the blood vessel  16 . This handle preferably has three actions: a first action in which the actuating rod  50  applies a proximal force to the hinge portion  542  to deploy and maintain arms  524  in a fully outward position ( FIG. 3 ); a second action to advance the needles  546  distally ( FIG. 3 ) and pull the needles  546  back proximally using one or more springs; and a third action in which the actuating rod  50  applies a distal force to the hinge portion  542  to retract the arms  524  ( FIG. 1 ). 
         [0035]    The locked position of the suture clasp arms  524  provides a stable base or foundation for holding the looped ends of the suture  40  while the needles  546  come in contact with the suture clasp arms  524  and capture the suture  40 . The suture clasp arms  524  are locked in the locked position by the proximal force of the actuating rod  50 , the stationary inside edges  536  of the apertures  508  and the protrusions  528  at the ‘elbow’ end of each arm  524  ( FIG. 3 ). Specifically, when the suture clasp arms  524  become substantially parallel with each other (i.e., each arm  524  is at an angle of approximately 90 degrees from the actuating rod  50 ), the protrusions  528  at the ‘elbow’ end of each arm  524  come into contact with each other and prevent the arms  524  from bending any further than the configuration shown in  FIG. 3 . The suture clasp member  500  cannot open any farther, even when the needles  546  are inserted distally and come in contact with the suture clasp arms  524 . The protrusions  528  prevent the suture clasp member  500  from moving unintentionally (opening any farther) when the needles  546  come in contact with the suture clasp arms  524 . This reduces the risk of the looped ends of the suture  40  being accidentally displaced from the suture clasps  544  when the needles  546  engage the suture clasps  544 . Thus, the combination of forces asserted by the actuating rod  50 , the proximal inside edges  536  of the aperture  508  and the two protrusions  528  sustain the suture clasp arms  524  in a rigid, locked position to facilitate the proper removal of the suture looped ends from the suture clasps  544 . 
         [0036]    The slits of the suture clasps  544  are angled in a proximal, radially inward direction. Thus, the face of the looped ends of the suture  40  face in a proximal, radially inward direction. In this configuration, there is less chance of the looped ends of the suture  40  falling off the suture clasps  544  improperly or prematurely. When the needles  546  engage the suture clasp arms  524 , the only direction the looped ends may move is in a proximal, radially inward direction, which is in the opposite direction of the inserted needles  546 . When the needles  546  retract proximally (as shown in  FIG. 3 ), the looped ends reliably fall into the suture catches  38  of the needles  546 . It is the proximal movement of the needles  546  which causes the suture catches  38  on the needles  546  to catch the looped ends of the suture  40 . This configuration does not rely on a radially outward tension in the looped ends to fasten the looped ends onto the suture catches  38  when the needles  546  are inserted distally. 
         [0037]    The description of each of introducer sheath  6 , suture catches  38 , needle incisions  248 , pivot pin  502  and lumen  530  is provided by reference to identically numbered elements in U.S. Pat. No. 6,245,079. 
         [0038]    A first important disadvantage of the suturing system illustrated in  FIGS. 1 ,  2  and  3  is that both of the arms  524  deploy to a position that is exactly 90 degrees from the axis of suturing device. This is because protrusions  528  abut one another when suture clasp  500  is fully opened (as shown in  FIG. 3 ). As described above, and in U.S. Pat. No. 6,245,079, it is an advantage of the system of  FIGS. 1 to 3  that arms  542  of suture clasp  500  do not open more than 90 degrees to reduce the risk of the looped ends of the suture  40  being accidentally displaced from the suture clasps  544  when the needles  546  engage the suture clasps  544 . 
         [0039]    Unfortunately, this is particularly problematic when suturing inside a blood vessel, since it may be preferred to enter the blood vessel at a non-perpendicular (e.g.: oblique) angle. In the system of  FIGS. 1 to 3 , the distal end of the suturing device must therefore be extended to some distance into the blood vessel during operation. 
         [0040]    A first feature of the embodiments of the present split arm suturing device is that each of its arms may be extended to different angles from the body of the device. In various embodiments, such angles are non-perpendicular to the longitudinal axis of the suturing device. More particularly, one arm may be extended to a position less than 90 degrees to the body of the device, whereas the other arm may be extended to a position more than 90 degrees to the body of the device. 
         [0041]    A second feature of various embodiments of the present split arm suturing device is that each of its arms may be extended one at a time. 
         [0042]    Separately, or taken together, these two features of the present invention provide a system which may be conveniently positioned to enter the blood vessel at a non-perpendicular angle, thus minimizing the potential for damage to the blood vessel, while ensuring proper placement of the suture. Thus, an operator can gain better access to smaller arteries and maintain a smaller elbow height, as compared to the suturing device of  FIGS. 1 to 3 . Thus, the present independently operable split arm suturing device offers significantly increased flexibility to the operator, as compared to the suturing device of  FIGS. 1 to 3 . 
         [0043]    Referring first to  FIGS. 4A and 4B , split arm suturing device  600  is shown prior to deployment (i.e. in its compact position). Suturing device  600  has moveable arms  610  and  620  which can be pivoted relative to the longitudinal axis L of suturing device  600 . Arms  610  and  620  may be independently moveable. As will be shown herein, when deployed, arm  610  will preferably be deployed in an anterior direction, and arm  620  will preferably be deployed in a posterior direction. 
         [0044]    Anterior arm  610  and posterior arm  620  may be made independently moveably by any of a variety of mechanisms, all keeping within the scope of the present invention. In the illustrated embodiments, arms  610  and  620  are independently actionable (i.e. moveable between compact and deployed positions) by flexible linkages in tension or compression. It is to be understood, however, that any push pull wire, gear or cam system, or any other suitable actuation system may be used, all keeping within the scope of the present invention. As illustrated in  FIG. 5B , arm  610  may be deployed by moving linkage  612 , and arm  620  may be deployed by moving linkage  622 . Specifically, by pulling linkage  612  proximally, anterior arm  610  rotates around pivot  614  until finger  611  contacts pivot stop  625 . Similarly, by pulling linkage  622  proximally, posterior arm  620  rotates (in an opposite direction) around pivot  624  until stop surface  621  contacts pivot stop  625 . Specifically, anterior arm  610  moves through angle A 1  when moved from its compact position to its deployed position. Referring to  FIG. 6 , posterior arm  620  moves through angle A 2  when moved from its compact position to its deployed position. As can be appreciated, by instead distally pushing linkages  612  and  622 , arms  610  and  620  can be moved back to their compact (i.e.: non-deployed) position. 
         [0045]    After deploying arms  610  and  620  (by retracting linkages  612  and  622 ) a first needle  616 , and a second needle  626  can then be advanced toward the distal ends of arms  610  and  620 , respectively to retrieve opposite ends of a suture  40 . In various embodiments, needles  616  and  626  are longitudinally advanceable along the shaft  601  of suturing device  600 , and exit through side wall openings  630  and  640  at locations proximal to the arms  610  and  620 , respectively. 
         [0046]      FIG. 6  shows an embodiment of the present invention deployed at a non-perpendicular angle relative to the axis of a blood vessel BV while the anterior arm  610  and posterior arm  620  are positioned longitudinally along the inside of the wall of blood vessel BV. Specifically, the distal end of suturing device  600  is positioned though a puncture P in blood vessel BV. 
         [0047]    Needles  616  and  626  are advanced longitudinally along through shaft, and exit through side wall openings  630  and  640 , and then puncture through respective needle punctures NP 1  and NP 2  in the wall of blood vessel BV. Thereafter, needles  616  and  626  can be retracted pulling the opposite ends of suture  40  upwardly through punctures NP 1  and NP 2  in the wall of blood vessel BV. 
         [0048]    In various embodiments, cuffs  618  and  628  can be provided at opposite ends of suture  40  to ensure that the distal ends of needles  616  and  626  connect securely onto the opposite ends of suture  40 . Various embodiments of cuffs, links, barbs, fasteners, or combinations thereof are also contemplated to ensure that the distal ends of needles  616  and  626  connect securely onto the opposite ends of suture  40 . Thus, cuffs  618  and  628  may be any of a variety of different designs. 
         [0049]    Referring again to  FIGS. 5A and 5B , by moving linkages  612  and  622  independently, and to different distances, arms  610  and  620  may be independently deployed to different angles relative to the longitudinal axis L of the body of suturing device  600 . For example, as shown in  FIGS. 5A and 5B , arm  610  may be rotated less than 90 degrees from the axis of the elongated body of suturing device  600 , whereas  620  may be rotated more than 90 degrees from the axis of the elongated body of suturing device  600 . 
         [0050]    As shown in  FIG. 6 , this advantageously allows the elongated body of suturing device  600  to be positioned through tissue Tract T (entering through skin S) at a non-perpendicular angle relative to the axis of a blood vessel BV while the first and second arms  610  and  620  are positioned longitudinally along the inside of the wall of blood vessel BV for placement of the suture axially along the blood vessel and across the puncture. Specifically, suturing device  600  can be used to position the ends of suture  40  at locations such that they can be retrieved by needles  616  and  626 , and pulled upwardly through needle punctures NP 1  and NP 2 , respectively. 
         [0051]    In various embodiments, the elongated body of suturing device  600  is sufficiently rigid to maintain alignment of needles  616  and  626  with arms  610  and  620 , respectively. As can be seen, in various embodiments, needles  616  and  626  may be of different lengths. 
         [0052]    As shown in  FIG. 7 , a pre-tied knot feature may also be incorporated into suturing device  600 . The pre-tied knot may initially be positioned wrapped around an exterior surface of the suturing device. Specifically, a length of suture  40  having opposite ends and a bight  680  of suture therebetween may be provided with bight  680  being disposed around an exterior surface of device  600 . Bight  680  may alternately be pre-arranged around one of the needles and within the elongated body. 
         [0053]    Bight  680  includes one or more loops of suture that form a pre-tied knot  690  when one or more ends of suture  40  are advanced through bight  680 . Bight  680  of suture may be prearranged in any of several configurations on the device. For example, bight  680  may be pre-arranged so as to define a square knot, a clinch knot or a variety of known or new surgical knots. 
         [0054]    In various embodiments, suture  40  is arranged to provide the pre-tied knot  680  that automatically travels down from the shaft of the device  600  where it is stored prior to delivery to the tissue wall. In various embodiments, to distinguish the ends of suture  40 , during deployment, the ends of the suture may be distinguished from each other by changing the color of one end (e.g. with dye), providing an attachment on one end (e.g. shrink wrap tubing, a bead, etc.) or with the suture itself (e.g. tying a knot in one end). 
         [0055]    In accordance with the present invention, suture bight  680  is disposed on the outside surface of device  600 , as shown. In this embodiment, suture  40  does not pass through the interior of the device. It should be understood, however, that other embodiments of the invention may include suture  40  and bight  680  stored inside the shaft or housing of the device rather than on the outside. Yet other configurations may include detachable tips and connecting filaments to enable a pre-tied knot. 
         [0056]    After needles  616  and  626  retrieve opposite ends of suture  40 , and pull these ends of the suture back up through the center of bight  680  to define the pre-tied knot  690 , and arms  610  and  620  are rotated back to a non-deployed position, device  600  may be removed from the patient. Pre-tied knot  690  will slide down the shaft, resulting in a suture pattern in which the opposite ends of suture  40  pass upwardly through the center of bight  680 . 
         [0057]    While embodiments and applications of this invention have been shown and described, it will be apparent to those skilled in the art that various modifications are possible without departing from the scope of the invention. It is, therefore, to be understood that within the scope of the appended claims, this invention may be practiced otherwise than as specifically described.