1. The Field of the Invention
The present invention relates generally to implanting medical devices within a patient. More particularly, the present invention relates to the field of patent foramen ovale (“PFO”) closure devices and delivery devices therefore.
2. The Relevant Technology
Other problems with this condition are that a blood clot may travel freely between the left or right atria of the heart, and end up on the arterial side. This could allow the clot to travel to the brain, or other organs, and cause embolization, or even a heart attack. These and other similar defects (septal or otherwise), where some tissue needs to be closed to function properly include the general categories of atrial septal defects (“ASDs”), ventricular septal defects (“VSCs”) and patent ductus arterosus (“PDA”), and so forth.
The PFO, which is an open flap on the septum between the heart's right and left atria, is generally identified at 50. In a normal heart, left atrium 40 receives oxygenated blood from the lungs via pulmonary arteries 75 and then delivers the blood to the left ventricle 80 via the bicuspid valve 45. However, in heart 10 some systemic venous blood also passes from right atrium 30 through PFO 50, mixes with the oxygenated blood in left atrium 40 and then is routed to the body from left ventricle 80 via aorta 85.
During fetal development of the heart, the interventricular septum 70 divides right ventricle 60 and left ventricle 80. In contrast, the atrium is only partially partitioned into right and left chambers during normal fetal development as there is a foramen ovale. When the septum primum 52 incompletely fuses with the septum secundum 54 of the atrial wall, the result is a PFO, such as the PFO 50 shown in
A tunnel 58 is defined by portions of septum primum 52 and septum secundum 54 between the merger points 56a and 56p which have failed to fuse. The tunnel 58 is often at the apex of the septum secundum 54 as shown. When viewed within right atrium 30, the portion of septum secundum 54 to the left of tunnel 58, which is referred to herein as the posterior portion 57p of the septum secundum 54, is longer than the portion of the septum secundum 54 to the right of tunnel 58, which is referred to herein as the anterior portion 57a of the septum secundum 54. In addition to being typically longer, the left portion also typically has a more gradual taper than the right portion, as shown. The area defined by the overhang of the anterior portion 57a of septum secundum 54 and the septum primum 52 and extending from the anterior merger point 56a toward tunnel 58 is an anterior pocket 59a. Similarly, the area defined by the overhang of the posterior portion 57p of septum secundum 54 and the septum primum 52 and extending from the posterior merger point 56p toward tunnel 58 is a posterior pocket 59p.
Conventional treatments for PFO (and related conditions), have generally involved invasive surgery, which presents a different, new set of risks to a patient. Although there are some less invasive treatments for PFO, these have typically been less efficient at closing the PFO opening than techniques involving invasive surgery. Accordingly, there is a continuing need for improved methods and devices for closing the PFO opening. In particular, there is a need for improved methods and devices for deploying PFO closure anchors in a patient.
To further clarify the above and other advantages and features of the present invention, a more particular description of the invention will be rendered by reference to specific embodiments thereof which are illustrated in the appended drawings. It is appreciated that these drawings depict only typical embodiments of the invention and are therefore not to be considered limiting of its scope. The invention will be described and explained with additional specificity and detail through the use of the accompanying drawings in which:
The invention relates to a medical system for use in reducing the size of an internal tissue opening, such as a PFO. In one embodiment, the medical system can include a PFO closure device and a delivery device therefore. The PFO closure device can include left and right anchors connected by a stem. The proximal end of the stem can include a set of internal threads for use in selectively connecting and disconnecting the delivery device to the PFO closure device. The delivery device can enable a practitioner to efficiently secure the PFO closure device in an internal tissue opening. Furthermore, the delivery device can enable a practitioner to adjust and reposition the PFO closure device after left and right anchors are deployed by selectively retracting the right anchor. The ability to reposition the PFO closure device provides practitioners with the added ability of more effectively reducing the size of an internal tissue opening by being able to adjust the PFO closure device during insertion to achieve the best position.
In one embodiment, the delivery device can include a tether shaft for removably coupling the delivery device to the PFO closure device. The tether shaft can include a first rigid portion and a second flexible portion, wherein the flexible second portion can be coupled to the stem of the PFO closure device through a threaded arrangement. Furthermore, one or more filaments can be coupled to a movable filament operating shaft and looped around one or more arms of the right anchor. Movement of the filament operating shaft can cause movement of the right anchor between a deployed and retracted position. Thus, a practitioner can move the filament operating shaft with respect to the PFO closure device to selectively deploy and/or retract the right anchor of the PFO closure device.
To facilitate disconnecting the delivery device and the PFO closure device, the tether shaft can be selectively linked to the filament operating shaft. In one embodiment, the tether shaft can be rotatably coupled to a shuttle block and the filament operating shaft can be coupled to a filament drive rod. The filament drive rod can be linked to the shuttle block by two rod pins, each positioned in the filament drive rod on opposing side of the shuttle block. As the filament drive rod moves in a distal direction, one of the rod pins contacts and engages the shuttle block, thus causing the shuttle block to move within a housing. However, prior to the rod pin contacting and engaging the shuttle block, movement of the filament drive rod in the distal direction can cause the one or more filaments to slacken, thus deploying the right anchors.
Linking of the tether shaft to the filament operating shaft can be facilitated by the configuration of the housing. The housing can be configured such that as the shuttle block moves in the distal direction, a pin, which can be located in an aperture or opening in the shuttle block, can be forced into a recess in the filament drive rod. As such, movement of the pin into the recess of the filament drive rod links the tether shaft to the filament operating shaft via the shuttle block. In this manner, a practitioner can safely move the tether shaft and the filament operating shaft in concert without concern that the right anchor will be inadvertently retracted by the delivery device.
These and other objects and features of the present invention will become more fully apparent from the following description and appended claims, or may be learned by the practice of the invention as set forth hereinafter.
The present invention extends to systems, methods, and apparatus for deploying a device that can be suitable for reducing the size of an internal tissue opening. By way of explanation, the devices disclosed herein can be used for any internal tissue opening, although frequent reference is made herein to closing a PFO opening of a heart tissue using right atrial anchors and left atrial anchors for purposes of simplicity. Accordingly, it will be understood that references to PFO openings are not limiting of the invention.
In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. It will be obvious, however, to one skilled in the art that the present invention may be practiced without these specific details. In other instances, well-known aspects of PFO closure devices or medical devices in general have not been described in particular detail in order to avoid unnecessarily obscuring the present invention. In addition, it is understood that the drawings are diagrammatic and schematic representations of certain embodiments of the invention, and are not limiting of the present invention nor are they necessarily drawn to scale.
The invention extends to systems, methods, and apparatus for deploying a device that can be suitable for reducing the size of an internal tissue opening. An apparatus for reducing the size of an internal tissue opening, such as a PFO closure device, can include a left atrial anchor and a right atrial anchor. The PFO closure device can be deployed by use of a delivery device. In one embodiment, the delivery device can be removably coupled to the PFO closure device by a threaded arrangement. In addition to being selectively removable from the PFO closure device, the delivery device can be configured to enable a practitioner to adjust and selectively manipulate the right anchor of the PFO closure device.
In one embodiment, the delivery device can include a tether shaft for removably coupling the delivery device to the PFO closure device and a housing enclosing at least a portion of the tether shaft. The tether shaft can include a first rigid portion and a second flexible portion, wherein the flexible second portion can be coupled to the stem of the PFO closure device through a threaded arrangement. However, the tether shaft can also be configured to have substantially the same rigidity along its length. Furthermore, the delivery device can be connected to the PFO closure device by one or more filaments. The filaments can be linked to the right and/or left anchor(s) such that movement of the filaments can cause movement of the respective anchor. In this manner, the anchor(s) of the PFO closure device can be selectively deployed and thereafter adjusted by a practitioner.
In one embodiment, the tether shaft can be selectively linked to the filaments to facilitate disconnecting the delivery device from the PFO closure device. For example, the tether shaft can be coupled to a movable member, such as a shuttle block, which in turn can be linked to a filament member, such as a filament drive rod or a filament operating shaft. The filament member can be coupled to the housing and can be linked to the shuttle block by a movable pin within the shuttle block. In one embodiment, the pin can move into an aperture or recess in the filament member, thus linking the filament member to the shuttle block. In this manner, the tether shaft can be linked to the filaments, such that movement of the filament member in a distal direction causes movement of the tether shaft in the distal direction.
The configuration the housing can facilitate linking of the tether shaft to the filament operating shaft. The housing can be configured such that as the shuttle block moves in the distal direction, a pin, which can be located in an aperture or opening in the shuttle block, can be forced into a recess in the filament drive rod. In this manner, the filament drive rod links the tether shaft to the filaments via the filament operating shaft, the pin and the shuttle block. In this manner, a practitioner can safely move the tether shaft and the filament operating shaft in concert with a reduced concern that the right anchor will be inadvertently retracted by the delivery device.
With reference now to
In the illustrated embodiment, PFO closure device 200 can include a stem 210, a right anchor 220 linked to stem 210 via a right anchor hub 222, and a left anchor 230 linked to stem 210 via a left anchor hub 232. Right and left anchors 220, 230 may include one or more arms 220a, b and 230a, b configured to engage the tissues of the heart 10. It will be understood that left anchor 230 and right anchor 220 can include more than the two arms and may have any of a variety of shapes known in the art. For example, U.S. patent application Ser. No. 11/102,095, filed Apr. 8, 2005 and incorporated herein by reference, discloses various compatible shapes and configurations for left and right anchors.
As further illustrated in
Filament control system 310 facilitates selective deployment of right anchor 220 and selective repositioning of right anchor 220 after right anchor 220 has been deployed. As such, filament control system 310 enables right anchor 220 to be selectively deployed and selectively retracted by a practitioner using delivery device 300. Likewise, handle 380 can work in conjunction with filament control system 310 to enable a practitioner to position PFO closure device 200 inside an internal tissue opening and to remove delivery device 300 when PFO closure device 200 is appropriately positioned.
As shown in the illustrated embodiment, a tether shaft 320 can extend through handle 380 in an arrangement such that tether shaft 320 is capable of rotational movement within handle 380. A filament drive rod 316 couples to handle 380 and terminates at the proximal end within handle 380 such that a filament cutting shaft 340 can be exposed therefrom within handle 380. Coupled to handle 380 adjacent a proximal end of filament cutting shaft 340 is a filament cutting handle 348. Filament cutting handle 348 can be pivotally coupled to handle 380 such that movement of a handle portion 348a about a pivot point 348c in a direction away from filament drive rod 316 causes a portion of filament cutting handle 348 to rotate. Rotation of filament cutting handle 348 in this manner causes an engagement portion 348b to contact filament cutting shaft 340. Continued rotation of filament cutting handle 348 in this direction will cause filament cutting shaft 340 to translate and move distally through filament drive rod 316.
While handle 380 is illustrated as being substantially hollow in construction, it will be appreciated that handle 380 can be constructed to be substantially solid with recesses of sufficient size and configuration so as to allow filament cutting handle 348 and filament cutting shaft 340 to operate as described herein. Furthermore, a pin can be implemented at pivot point 348c so as to pivotally couple filament cutting handle 348 to handle 380 and to enable filament cutting handle 348 to pivot about pivot point 348c. Furthermore, it will be appreciated by one of ordinary skill in the art in view of the disclosure provided herein that filament cutting handle 348 may alternatively be positioned in housing 312, or may be integrally coupled into filament cutting shaft 340 such that filament cutting shaft 340 and filament cutting handle 348 form a single piece.
In the illustrated embodiment, filament control system 310 can include a housing 312, a shuttle block 314 positioned in housing 312 and moveable along at least a part of the length of housing 312, filament drive rod 316 and a filament operating shaft 318 coupled to filament drive rod 316. In one embodiment, housing 312 can include a cylindrical tube having an elongate hollow portion extending at least partially along the length of housing 312 and configured to house various elements of filament control system 310.
In the illustrated embodiment, filament drive rod 316 and tether shaft 320 connect housing 312 to handle 380. Tether shaft 320 extends through handle 380 and can be capable of rotational movement therein. Filament drive rod 316 can be fixed to handle 380 such that movement of handle 380 causes movement of filament drive rod 316. Collars 322a, b are coupled to tether shaft 320, each on opposite sides of shuttle block 314 such that movement of tether shaft 320 causes movement of shuttle block 314.
As shown in the illustrated embodiment, shuttle block 314 includes an aperture or opening 324 in which a pin 326 is received. Pin 326 can be utilized to link tether shaft 320 to one or more filaments 322. Filament drive rod 316 can include a first rod pin 330a and a second rod pin 330b positioned in and extending through the sidewalls of filament drive rod 330. Rod pins 330a, b are utilized in connection with safety features of delivery device 300, as will be discussed hereinafter.
In one embodiment, pusher catheter 332 can be a double-lumen catheter with tether shaft 320 being housed in a first lumen of pusher catheter 332 and filament operating shaft 318 being housed in a second lumen of pusher catheter 332. Tether shaft 320 can be capable of rotational and translational movement within pusher catheter 332. Likewise, filament operating shaft 318 can be capable of translational movement within pusher catheter 332. In this manner, a user of delivery device 300 can rotate tether shaft 320 about its central axis relative to pusher catheter 332. Also, a practitioner can move the distal end of filament operating shaft 318 closer to or further away from PFO closure device 200. The ability to move the distal end of filament operating shaft 318 closer or further away from PFO closure device 200 enables the practitioner to selectively control deployment of an atrial anchor, such as right anchor 220, of PFO closure device 200.
In the illustrated embodiment, pusher catheter 332 can be coupled to the distal end of housing 312 and can extend to substantially the distal end of delivery device 300. Pusher catheter 332 can include a pusher catheter extending shaft 334 and a pusher catheter tip 336 at the distal end of pusher catheter extending shaft 334. Pusher catheter extending shaft 334 can be configured to provide some degree of rigidity to a flexible second portion 320b of tether shaft 320 to facilitate placement of PFO closure device 200. Pusher catheter extending shaft 334 can extend from the distal end of filament operating shaft 318 and can terminate at pusher catheter tip 336.
Pusher catheter tip 336 can be configured to engage a proximal end of stem 210 of PFO closure device 200. Furthermore, pusher catheter tip 336 can be configured to be repositionable over stem 210 after pusher catheter tip 336 has been disengaged from stem 210. This can be done by a user moving tether shaft 320 in the proximal direction with respect to housing 312. With the pusher catheter 332 coupled to housing 312 and pusher catheter tip 336 coupled to pusher catheter 332, movement of tether shaft 320 in this manner would force the proximal end of stem 210 back into pusher catheter tip 336.
As shown in the illustrated embodiment, tether shaft 320 can include a first portion 320a and a second portion 320b coupled thereto. First portion 320a can include a resilient rod configured to be rotatable and provide enough stiffness to delivery device 300 so as to substantially prevent bucking of delivery device 300 as it is being used to deliver a PFO closure device 200. First portion 320a of tether shaft 320 further can include a threaded portion at the distal end which can be configured to be received within and engage internal threads of the second portion 320b of tether shaft 320. While the illustrated embodiment demonstrates that first and second portions 320a,b may be coupled through use of threads, it will be understood that a variety of types of connection means may be employed to connect first portion 320a to second portion 320b.
Second portion 320b can include a flexible rod comprising a shape memory material such as a shape memory alloy, a shape memory polymer, or the like. In one embodiment, the shape memory material can be NITINOL. Furthermore, coupled to the distal end of second portion 320b can be a threaded portion 320c. Threaded portion 320c can be configured to correspond to a set of internal threads 212 at the proximal end of stem 210. As will be appreciated, rotation of tether shaft 320 with respect to PFO closure device 200 will cause threaded portion 320c of tether shaft 320 to disengage from the internal threads 212 of stem 210. In this manner, delivery device 300 can be disengaged from PFO closure device 200 subject to connection by one or more filaments 322.
Furthermore, it will be understood by one of ordinary skill in the art in view of the disclosure provided herein that a variety of types of connection means may be employed to selectively couple tether shaft 320 to PFO closure device 200. For example, in an alternative embodiment, tether shaft 320 can be coupled to PFO closure device 200 by a hook and latch. Furthermore, it will be understood by one of ordinary skill in the art that a securing agent, such as an adhesive, can be applied between first portion 320a and second portion 320b of tether shaft 320 such that rotation of tether shaft 320 can cause disengagement of PFO closure device 200 from tether shaft 320 rather than disengagement of first portion 320a from second portion 320b. Alternatively, reverse threads can be utilized in one of the two coupling arrangements.
As shown in the illustrated embodiment, filament operating shaft 318 can be connected to arm 220b of right anchor 220 by filament 322b. In this manner, movement of filament operating shaft 318 causes movement of right anchor 220, specifically arm 220b, when filament 322b is taut. Filament operating shaft 318 can include openings 318a, b through which one or more filaments 322 pass.
Openings 318a, b in filament operating shaft 318 can be configured to facilitate severing of filaments 322 in preparation of removal of delivery device 300 from a patient. Openings 318a, b can be sized and configured to allow one or more filaments 322 to be positioned therethrough. Openings 318a, b can be positioned and located at the distal end of filament operating shaft 318. At the distal end of filament operating shaft 318 and adjacent to openings 318a, b, is a rounded portion that provides a rounded surface for filaments 322, such that when tension is induced on filaments 322, filaments 322 are not severed by a sharp outside edge of openings 318a, b.
Filament 322b can be coupled on one end to filament operating shaft 318 then pass through openings 318a, b, loop around arm 320b and then can be fixed to the delivery device 300. In this manner, as filament operating shaft 318 is moved in the distal direction with respect to housing 312, at least one end of filament 322b moves towards PFO closure device 200, thus enabling arm 220b to deploy. Likewise, as filament operating shaft 318 is moved in the proximal direction with respect to housing 312, at least one end of filament 322b moves away from PFO closure device 200, thus retracting arm 220b of right anchor 220 toward pusher catheter shaft 334.
Filament cutting shaft 340 can be housed within filament operating shaft 318 and can be capable of translational and/or rotational movement therein. In the illustrated embodiment, a filament cutting shaft can include a filament cutting portion 338 at the distal end of filament cutting shaft 340. Filament cutting portion 338 may be a sharp tip on the terminating distal end of filament cutting shaft 340 or may be a separate piece connected to the distal end of filament cutting shaft 340. Filament cutting portion 338 can be configured to sever filaments 320, which are positioned in openings 318a, b. In the illustrated embodiment, filament cutting portion 338 can include a substantially cylindrical member whose outer diameter substantially corresponds with the inner diameter of filament operating shaft 318. In this manner, as filament cutting portion 338 moves past openings 318a, b, filaments 322 are severed by a sharp leading edge of filament cutting portion 338.
It will be understood by one of ordinary skill in the art in view of the disclosure provided herein that filaments 322 can be actuated and/or severed by a variety of different configurations. For example, in one embodiment, filaments 322 can be coupled to filament cutting shaft 340, wherein filament cutting shaft can be rotated thus causing filaments 322 to be wound around filament cutting shaft 340. In this embodiment, an atrial anchor, such as a right anchor, which is looped by a filament, can be selectively moved between the deployed and retracted orientation by rotating filament cutting shaft. In an alternative embodiment, filaments 322 can be fixed to filament operating shaft 318, wherein filament operating shaft 318 can be rotated in a similar manner, thus causing filaments 322 to wind around filament operating shaft 318.
In an alternative embodiment, filaments 322 can selectively be disconnected from PFO closure device 200 by rotating filament cutting shaft 340. In this alternative embodiment, filament cutting shaft 340 can include an aperture through which one end of a filament 322 is received. Filament 322 can then be wrapped around filament cutting shaft 340 so as to secure the end of filament 322. After PFO closure device 200 has been placed, a practitioner could disconnect filament 322 from right anchor 220 by unwrapping filament 322 from filament cutting shaft 340. Filament 322 can be unwrapped by rotating filament cutting shaft 340. The atrial anchors can be manipulated and the filaments can be severed by a variety of different mechanisms and/or configurations as will be appreciated by one of ordinary skill in the art in view of the disclosure provided herein.
Rod pin ramp 342 can be configured to force pin 326 out of recess 341 to enable a user to retract right anchors 220 as will be discussed more fully herein. Rod pin ramp 342 defines a distal portion of recess 341 and can be of sufficient pitch so as to cause pin 326 to move upward toward a first top surface 312a of housing 312 when filament drive rod 316 is moved in the proximal direction with respect to shuttle block 314.
Filament drive rod 316 can be coupled to handle 380 such that movement of handle 380 causes movement of filament drive rod 316. In one embodiment, filament drive rod 316 can include a hollow substantially rigid shaft. First rod pin 330a can be configured and positioned in filament drive rod 316 so as to cause filament drive rod 316 to engage shuttle block 314 as filament drive rod 316 is moved in the distal direction with respect to housing 312. Furthermore, first rod pin 330a can be configured to facilitate placement of pin 326 in recess 341.
First rod pin 330a can be positioned in and can extend through the sidewalls of filament drive rod 316. First rod pin 330a can be of sufficient length such that as filament drive rod 316 is advanced through shuttle block 314, first rod pin 330a can contact first side 314a of shuttle block 314. First rod pin 330a can be positioned along the length of filament drive rod 316, such that as first rod pin 330a contacts first side 314a of shuttle block 314, opening 328 substantially aligns with recess 341 as illustrated. In this manner, as filament drive rod 316 moves in the distal direction with respect to housing 312, the top portion of pin 326 can contact a housing pin ramp 344, thus forcing pin 326 into recess 341 of filament drive rod 316.
Linking of tether shaft 320 to filaments 322 in this manner provides safety benefits. Specifically, linking of tether shaft 320 to filaments 322 enables pusher catheter tip 336 to be disengaged from stem 210 without concern that filaments 322 are manipulating the position of right anchor 220, namely inadvertently deploying and/or retracting right anchor 220.
Second rod pin 330b can be positioned in filament drive rod 316 and configured to reduce the risk that filaments 322 are prematurely severed due to a user pulling handle 380 in the proximal direction. Second pin rod 330b can be positioned in and extend through the sidewalls of filament drive rod 316. Second pin rod 330b can be positioned in filament drive rod 316 such that as filament drive rod 316 is advanced through shuttle block 314 in the proximal direction with respect to shuttle block 314, second rod pin contacts a second side 314b of shuttle block 314.
Second pin rod 330b can be positioned along the length of filament drive rod 316 so as to substantially prevent a user from inducing tension in filaments 322 sufficient to break filaments 322. For example, when right anchor 220 is completely retracted due to the tension in filaments 322, second rod pin 330b can be in contact with and engage second side 314b of shuttle block 314. In this manner, movement of filament drive rod 316 in a proximal direction with respect to housing 312 corresponds with movement of tether shaft 320 in the proximal direction with respect to housing 312, thus preventing filaments 322 from being stretched to failure.
In the illustrated embodiment, housing 312 can include a first top surface 312a, a second top surface 312b, a bottom surface 312c and a housing pin ramp 344 connecting first top surface 312a to second top surface 312b. First top surface 312a can be a surface on which pin 326 can slide when pin 326 is not within recess 341 of filament drive rod 316. Second top surface 312b can be positioned below first top surface 312a and can provide a surface on which shuttle block 314 can slide. Bottom surface 312c provides a surface on which a bottom surface of shuttle block 314 can slide. The distance between second top surface 312b and bottom surface 312c can correspond to the height of shuttle block 314, such that as pin 326 is received within recess 341 of filament drive rod 316, second top surface 312b helps to maintain pin 326 within recess 341 as shuttle block 314 moves in housing 312.
Housing pin ramp 344 can be configured to position pin 326 in recess 341 as filament drive rod 316 is advanced in the distal direction with respect to housing 312. Housing pin ramp 344 can be positioned in housing 312 so as to facilitate the linking of tether shaft 320 to one or more filaments 322 after right anchor 220 has been deployed in preparation for removal of delivery device 300 from a patient. The linking of tether shaft 320 to filaments 322 can be advantageous for safety concerns. For example, linking in this manner reduces risks to patients because the only connection between PFO closure device 200 and delivery device 300 are flexible portion 320b of tether shaft 320 and filaments 322.
It will be understood by one of ordinary skill in the art in view of the disclosure provide herein that a variety of configurations of filament control system 310 may be utilized without departing from the scope and spirit of the invention. For example, in one embodiment, tether shaft 320 can be linked to filament drive rod 316 by a linkage positioned outside of housing 312 which couples tether shaft 320 to filament drive rod 316. Alternatively, a linking assembly can be utilized so as to selectively couple tether shaft 320 to filament drive rod 316 when filament drive rod 316 and tether shaft 320 are in a particular orientation with respect to each other. Furthermore, in an alternative embodiment, filament drive rod 316 and filament operating shaft 318 comprise a single element.
Filament operating shaft 318 can be configured to facilitate movement of one or more filaments 322 to selectively deploy and retract right anchor 220. Filament operating shaft 318 can be coupled to filament drive rod 316, such that movement of filament drive rod 316 causes movement of filament operating shaft 318. In this manner, handle 380 can be linked to filament operating shaft 318, such that movement of handle 380 results in movement of filament operating shaft 318. In one embodiment, filament operating shaft 318 can include a hollow shaft extending from filament drive rod 316 to the distal portion of delivery device 300. In the illustrated embodiment, filament operating shaft 318 can be at least partially housed by filament drive rod 316 and can extend to handle 380. As a matter of clarification, in the illustrated embodiment, filament operating shaft 318 is cross-sectioned with respect to handle 380, but is not shown in cross-section with respect to filament control system 310.
Collars 324a, b are configured to link tether shaft 320 to shuttle block 314. Collars 324a, b are located on opposite sides of shuttle block 314 and are fixed to tether shaft 320. In one embodiment, collars 324a, b are compressed onto tether shaft 320 in an interference fit type arrangement. In an alternative embodiment, collars 324a, b are fixed to tether shaft 320 by an adhesive, or alternatively, by screws positioned through collars 324a, b, respectively, to tether shaft 320. Collar 324a can be positioned on the first side 314a of shuttle block 314 and collar 324b can be positioned on second side 314b of shuttle block 314. In this manner, tether shaft 320 can be capable of rotating within shuttle block 314, but translation of tether shaft 320 with respect to shuttle block 314 can be substantially prohibited.
Handle 380 can be configured to facilitate placement of PFO closure device 200. Handle 380 can be of sufficient size and shape to allow a practitioner to hold and move handle 380. Handle 380 can be connected to filament control system 310 via tether shaft 320 and filament drive rod 316. Handle 380 can be configured to enable tether shaft 320 to rotate therein and translate at least partially therethrough. Tether shaft 320 can be prevented from pulling through handle 380, at least in part, by knob 346. Knob 346 can be coupled to the proximal end of tether shaft 320. Knob 346 can be configured to facilitate removal of tether shaft 320 from PFO closure device 200. Knob 346 can be coupled to the proximal end of first portion 320a of tether shaft 320. Rotation of knob 346 causes rotation of tether shaft 320.
Knob 346 can also serve to reduce the likelihood of filaments 322 being damaged. For example, the length of tether shaft 320 can be such that as handle 380 is moved in the proximal direction, knob 346 will contact handle 380 when filaments 322 are taut and right anchor 220 is in a fully retracted orientation. In this manner, knob 346 can serve to substantially prevent filaments 322 from being damaged due to movement of handle 380.
Housed within and coupled to handle 380 can be filament drive rod 316 and filament cutting handle 348. Housed within filament drive rod 316 can be filament operating shaft 318 and filament cutting shaft 340. Filament cutting handle 348 can be the actuation mechanism utilized to sever filaments 322 upon disconnecting delivery device 300 from PFO closure device 200. Filament cutting handle 348 can be rotatably or pivotally coupled to handle 380. Filament cutting handle 348 can be of a sufficient length to actuate filament cutting shaft 340 when filament cutting handle 348 is rotated or pivoted, as discussed above. As filament cutting handle 348 is rotated in the direction shown, a portion of filament cutting handle 348 contacts filament cutting shaft 340 causing filament cutting shaft 340 to translate through filament operating shaft 318. As filament cutting shaft 340 is translated through or moves through filament operating shaft 318, filament cutting portion 338 can move to sever filaments 322 at openings 318a, b in filament operating shaft 318.
It will be appreciated by one of ordinary skill in the art in view of the disclosure provided herein that filament cutting shaft 340 can be actuated by alternative configurations. For example, in an alternative embodiment, filament cutting shaft 340 comprises a handle member coupled thereto such that movement of the handle member is the distal direction causes the filament cutting shaft 340 to slide or move within filament operating shaft 318 to sever filaments 322. In an alternative embodiment, a button or knob can be coupled to filament cutting shaft 340 through filament drive rod 316 and filament operating shaft 318. In this embodiment, a slot can be formed in filament drive rod 316 and filament operating shaft 318 sufficient to allow movement of the button or knob to in turn move filament cutting shaft 340 to sever filaments 322.
With reference to
Once the distal end of delivery sheath 400 is positioned at the end of tunnel 58 as illustrated in
A practitioner is able to utilize housing 312 to advance PFO closure device 200 through delivery sheath 400 by moving housing 312 in the distal direction. As will be appreciated, if a practitioner simply pushes on handle 380 to advance PFO closure device 200 through delivery sheath 400, pin 326 may contact housing pin ramp 344 and be inadvertently forced into recess 341.
In the event that the user or practitioner wishes to reposition PFO closure device 200, a user would simply move the handle 380 in the proximal direction with respect to housing 312 so as to move filament operating shaft 318 in the proximal direction. Movement in this manner causes filaments 322 to pull on arms of right anchor 220, thus moving the ends of arms of right anchor 220 in the proximal direction. In this manner, the user would be able to reposition and move the PFO closure device 200 and then again deploy right anchor 220 by moving handle 380 in the distal direction until the practitioner is satisfied with the location of PFO closure device 200.
Once right and left anchors 220, 230 are deployed and PFO closure device 200 is in a satisfactory position, the practitioner can disengage pusher catheter tip 336 from the proximal end of stem 210. This is done by moving the handle 380 in the distal direction with respect to housing 312 until pin 326 moves from the first to the second position, as shown in
Furthermore, should PFO closure device 200 require repositioning, a user would have the option of repositioning PFO closure device 200. Repositioning can be effectuated by reengaging pusher catheter tip 336 with the proximal end portion of stem 210 and inducing tension in filaments 322 by moving proximally filament operating shaft 318. Pusher catheter tip 336 can be reengaged with stem 210 by a user grasping knob 346 and moving tether shaft 320 in the proximal direction with respect to housing until pusher catheter tip 336 moves over and mates with the outer surface of stem 210. Furthermore, right anchors 220 can be retracted by a user moving handle 380 in the proximal direction with respect to housing 312, thus causing filament operating shaft 318 to translate proximally.
A user can disengage pusher catheter tip 336 from stem 210 by observing the following procedure. Once PFO closure device 200 is in position and filaments 322 are slackened, a user moves handle 380 toward housing 312 until first rod pin 330a contacts and engages first side 314a of shuttle block 314. As a user continues to move handle 380 toward housing 312, first rod pin 330a causes shuttle block 314 to move in the distal direction. As shuttle block 314 moves in the distal direction, the top portion of pin 326 will contact housing pin ramp 344, thus forcing pin 326 into recess 341 of filament drive 316. Once pin 316 is in recess 341, tether shaft 320 is linked to filaments 322 by filament drive rod 316 and filament operating shaft 318. A user would then continue to move handle 380 toward housing 312, and at the same time move housing 312 and handle 380 in the proximal direction so as to prevent right anchor 220 from being pushed into left atrium 40.
The present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative and not restrictive. Exemplary claims have been included herein to illustrate embodiments of the invention. Although exemplary claims are presented, the invention is not limited to these claims, and the applicant reserves the right to present different or other claims in the future in view of the embodiments of the invention described herein.
This application claims benefits from U.S. Provisional Patent Application, Ser. No. 60/720,911, filed on Sep. 26, 2005, entitled “DELIVERY SYSTEM FOR PFO CLOSURE DEVICE”, the disclosure of which is hereby incorporated by reference.
Number | Date | Country | |
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60720911 | Sep 2005 | US |