Medical device release apparatus, systems and methods of use

Abstract

The present invention relates to a medical device delivery apparatus comprising a head element (11) at a proximal end of the apparatus, the head configured to extend through and protrude proximally from the medical device, the head element having one or more hook elements (13) for engaging a control loop coupled to the medical device, the one or more hook elements being axially fixed relative to the head element.

Description

[Technical field]

[0001] The present invention relates to a medical device release apparatus and method of use thereof. [Background technology]

[0002] In this regard, medical devices such as intravascular stent devices are commonly attached to their delivery systems using a combination of control loops, eyelets and release wires. As shown in Figures 1-3, this connection is achieved by threading the free end of the control loop 2 of the control thread through an eyelet 3 and securing the other end to the distal end of the delivery system. A release wire 4 is then passed through the open loop of the control thread, which is formed as the control thread passes through the eyelet, to prevent the control thread from being pulled back through the eyelet.

[0003] Removal of the release wire 4 allows the control loop 2 to be pulled back through the eyelet and the medical device 5 to be released from the delivery system, freeing the device from the delivery system.

[0004] Problems can arise with this configuration if the release wire becomes damaged and cannot be removed from the control loop, which would prevent the user from being able to remove the delivery system from the patient without additional rescue procedures or a full conversion to laparotomy.

[0005] Problems can also arise if the user forgets to remove the release wire before attempting to remove the delivery system, which can cause the device to move from the intended sealing area, destroying the seal and damaging the blood vessel in the process. Summary of the Invention [Problem to be solved by the invention]

[0006] The present invention provides an apparatus and method that aims to alleviate the problems of such known arrangements. [Means for solving the problem]

[0007] In accordance with the present invention, a medical device delivery apparatus is provided, the apparatus comprising a head element at a proximal end of the apparatus, the head configured to extend through and protrude proximally from the medical device, the head element having one or more hook elements for engaging a control loop coupled to the medical device, the one or more hook elements being axially fixed to the head element.

[0008] In this manner, the medical device may be released simultaneously as the delivery system is withdrawn, without additional mechanical manipulation of the apparatus.

[0009] Preferably, the one or more hook elements face forward, with a free end of the one or more hook elements extending in a direction toward the proximal end of the head element.

[0010] Conveniently, the head element has two hook elements.

[0011] Preferably, the hook elements are provided on diametrically opposite sides of the head element.

[0012] Conveniently, one or more hook elements extend proximally and project radially outwardly from the longitudinal profile of the head element.

[0013] Preferably, the one or more hook elements are provided at a distal end of the head element.

[0014] Conveniently, the one or more hook elements are each in the form of an angled slot, open at a proximal end and closed at a distal end.

[0015] Preferably, each slot has a tapered profile.

[0016] Conveniently, the head element comprises a head body and a head plate connected to a distal end of the head body to define said one or more hook elements between the head body and the head plate.

[0017] Preferably, the head body is chamfered at a distal end thereof to define said one or more hook elements.

[0018] Conveniently, the device further comprises one or more attachment points for the ends of the control loop.

[0019] Preferably, the one or more attachment points are provided on the head element proximal to the one or more hook elements.

[0020] Conveniently, the one or more hook elements are movable between a deployed position and a non-deployed position.

[0021] Preferably, the one or more hook elements are pivotable between a deployed position and a non-deployed position.

[0022] Conveniently, the one or more hook elements are retractable so as to be substantially flush with the longitudinal profile of the device.

[0023] Preferably, the one or more hook elements are profiled such that rotation of the head element facilitates release of any control loop engaged by the one or more hook elements.

[0024] Preferably, the one or more hook elements comprise an angled portion having a radially extending portion, the radially extending portion configured to engage the control loop.

[0025] The apparatus preferably further comprises alignment means for aligning said one or more hook elements with one or more eyelets of a medical device.

[0026] According to a further aspect of the present invention, there is provided a medical device deployment system for deploying a medical device, the medical device deployment system comprising a medical device delivery apparatus having a head element at a proximal end of the apparatus, the head configured to extend through and protrude proximally from the medical device, the head element having one or more hook elements for engaging a control loop coupled to the medical device, the one or more hook elements being axially secured to the head element.

[0027] According to yet another aspect of the present invention, there is provided a method of deploying a medical device using the claimed delivery device or deployment system, the method comprising the steps of passing the delivery device through a medical device and protruding from a proximal end of the medical device, coupling the medical device to one or more hook elements of the delivery device using one or more control loops, advancing the device to a deployment site, deploying the medical device at the site, and retracting the delivery device, wherein the one or more control loops are released from the one or more hook elements, and the one or more hook elements are axially secured to the head element.

[0028] Preferably, the one or more control loops are attached to a head element of a delivery apparatus, pass through one or more eyelets on the medical device, then pass around the one or more hook elements before passing through the one or more eyelets again.

[0029] Conveniently, one or more control loops are attached to the medical device and pass around one or more hook elements.

[0030] Preferably, the medical device has a wavy proximal end profile and the one or more control loops are attached to a proximal peak of the medical device.

[0031] Conveniently, one or more hook elements are moved to facilitate disengagement of one or more control loops.

[0032] Preferably, one or more hook elements are pivoted rearward to facilitate disengagement of one or more control loops.

[0033] Conveniently, the head element rotates about a longitudinal axis of the head element to facilitate disengagement of one or more control loops. [Brief description of the drawings]

[0034] [Figure 1] FIG. 1 illustrates a known arrangement for delivering a medical device to a site. [Diagram 2] FIG. 2 illustrates a known configuration for delivering a medical device to a site. [Diagram 3] FIG. 3 shows a known arrangement for delivering a medical device to a site. [Figure 4] 4a to 4d show a first embodiment of the present invention. [Diagram 5] 5a to 5e show a second embodiment of the present invention. [Figure 6] 6a to 6c show a third embodiment of the present invention. [Figure 7] 7a and 7b show a fourth embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0035] Embodiments of the invention will now be described by way of example and with reference to the accompanying drawings, in which:

[0036] 1-3, as discussed above, relate to conventional delivery systems for intravascular devices. Such systems can experience problems if the release wire is damaged or if the user forgets to remove the release wire before attempting to remove the delivery system.

[0037] Accordingly, the present invention seeks to provide a medical device delivery system that does not require a release wire.

[0038] In this regard, as shown in Figures 4a-4d, the delivery device 10 includes a tip or head element 11 at a proximal end of a longitudinal axis 12. The head element has a hook element 13 that projects radially outward and forward toward the proximal end of the head element. The hook element may be formed in any suitable manner, and in this embodiment is formed by chamfering the distal end of the head element to form a slot 15 and coupling a plate 14 thereto. As shown, an end 16 of the plate preferably projects radially outward of the general outer longitudinal profile of the head element 11.

[0039] As shown, the head element is arranged to extend through the interior of a medical device 17, such as an intravascular stent, such that in use the head element 11 projects from the proximal end of the medical device 17. For clarity, the structure of the medical device is not shown in detail in the figures, but may comprise an expandable stent device having an undulating proximal end, generally designated 17. In the embodiment of Figures 4a-d, a control loop 19 is attached at one end to the head element at an attachment point 20 above the hook element, i.e. near the proximal end of the head element.

[0040] Each control loop extends rearward and passes through an eyelet 21 which is connected to a medical device. The loop then returns to the head element, loops around the hook element 11, returns to the eyelet and then ascends towards the proximal end of the apparatus.

[0041] Figures 4a-4d show the progression of the head element relative to the medical device 17. In Figure 4a, the medical device has been moved into the correct position relative to the site where it can be fixed in place. This can be done by expanding the device to seal against the interior surface of the vessel in which it is deployed.

[0042] Once properly secured in place, the delivery device is retracted as shown in Figures 4b-4d, passing rearward within the device towards the distal end of the device.

[0043] Once the eyelet is level with the hook element 11, the control loop is no longer pulled downward into the hook element and therefore may begin to disengage from the hook element as shown in Figures 4b and 4c. Then, in Figure 4d, the control loop is no longer hooked around the hook element and can pass through the eyelet as the delivery device is retracted.

[0044] The design of the head element eliminates the need for release wires in the attachment method and allows the device to be released as soon as the delivery system is removed from the patient, without requiring any additional action from the user.

[0045] As mentioned above, this can be accomplished by increasing the length of the control loop and incorporating two hooks collinear with the control loop, one on each side of the head element or tip. To assemble the device into a delivery system, the control loop is fed through an eyelet and then the free end is attached to the hook on the tip.

[0046] When the eyelet of the device is lower than the tip, the control loop remains attached to the hook, thus allowing the device to remain attached to the delivery system during compression and unsheathing, but when the tip moves below the eyelet (e.g., when the delivery system is removed from the device), the control loop disengages from the hook and can be pulled out of the eyelet, freeing the device from the delivery system.

[0047] Such an arrangement of the invention means that no separate mechanical step is required to withdraw the device: the device is released simply by withdrawing the head element, i.e. the tip of the delivery system.

[0048] In this regard, the hook elements are axially fixed in place at the tip of the delivery system, and the relative position of the graft to the hooks secures or releases the device.

[0049] In this regard, the hook element / slot should preferably be integrated into the delivery system, at a height above the device, and angled towards the device so that the "closed" portion of the hook / slot is closest to the device, with one end open and the control loop free to move away. The control loop is preferably long enough to be attached to the delivery system at one end (leaving the other end free) and looped through an eyelet to attach to the hook. The eyelet is preferably attached to the device.

[0050] A second embodiment of the present invention will now be described with reference to Figures 5a to 5e.

[0051] In this embodiment, the control loop 30 is attached to a peak 31 of the first ring of the medical device. When the device is assembled into a delivery system, the control loop is simply latched onto a hook element 32 provided on the tip. This attachment method works in the same way as described above for the first embodiment (the relative position of the tip to the control loop attachment point determines whether the device is attached to the delivery system). However, in this embodiment, the control loop attached to the device is left in place.

[0052] The hook element can be provided with a second configuration that allows it to be detached from the head element or tip while leaving the control loop free to pull from the eyelet. This is useful in any situation where the control loop becomes caught in the hook element and the device cannot be released.

[0053] Figures 6a-6c show a third embodiment in which the hook elements 40 can be retracted to release the device.

[0054] As shown in the fourth embodiment of Figures 7a and 7b, the hook elements 50 can be angled or shaped so that rotation of the head element 11 also causes the control loop to exit the hook, or makes it easier for the control loop to exit the hook.

[0055] The control loop 52 may extend the length of the delivery system and can be cut and removed to free the device from the delivery system, which acts as a fail-safe in case the control loop gets caught on the hook element.

[0056] Various embodiments of the present invention maintain the advantages of tethering the top of a medical device to a delivery system for more accurate deployment and easier manufacturing, but they eliminate any additional steps required for the user to remove the device from the delivery system, such as removing release wires, top caps, etc. associated with known methods.

Claims

1. 1. A medical device delivery apparatus, comprising: a head element at a proximal end of the device; one or more hook elements of the medical device delivery apparatus projecting radially outward and forwardly toward a proximal end of the head element; the head element of the medical device delivery apparatus is configured to extend through and protrude proximally from the medical device; the one or more hook elements on the head element engage a control loop that is coupled to the medical device; one end of the one or more hook elements is secured to a distal end of the head element and another end of the one or more hook elements projects proximally; An apparatus comprising at least one of the control loops of the medical device delivery apparatus having a first end attached to the head element and a second end that is a free end engageable with the hook element.

2. the one or more hook elements face proximally; The device of claim 1 , wherein a free end of the one or more hook elements extends in a direction toward the proximal end of the head element.

3. The device of claim 1 , wherein the head element has two hook elements.

4. The device of claim 3 , wherein the hook elements are provided on diametrically opposite sides of the head element.

5. The device of claim 1 , wherein the one or more hook elements extend proximally and project radially outward from a side of the head element.

6. The device of claim 1 , wherein the one or more hook elements are provided on the distal end of the head element.

7. The device of claim 1 , wherein the one or more hook elements are each in the form of an angled slot, open at a proximal end and closed at a distal end.

8. The apparatus of claim 7 , wherein each slot has a tapered profile.

9. the head element comprises a head body and a head plate; The device of claim 1 , wherein the head plate is coupled to a distal end of the head body to define the one or more hook elements between the head body and the head plate.

10. The device of claim 9 , wherein the head body is chamfered at the distal end of the head body.

11. The apparatus of claim 1, wherein the head element has one or more attachment points for attaching the first end of the control loop to the head element.

12. The device of claim 11 , wherein the one or more attachment points are provided on the head element and proximal to the one or more hook elements.

13. The device of claim 1 , wherein the one or more hook elements are movable relative to the head element between a deployed position and a non-deployed position.

14. The device of claim 13 , wherein the one or more hook elements are pivotable between the deployed and undeployed positions.

15. The device of claim 13 , wherein the one or more hook elements are retractable relative to the head element.

16. The device of claim 1 , wherein the one or more hook elements are profiled such that rotation of the head element about a longitudinal axis of the head element facilitates release of any control loop engaged by the one or more hook elements.

17. the one or more hook elements include an angled portion having a radially extending portion; The apparatus of claim 16 , wherein the radially extending portion is configured to engage a control loop.

18. The apparatus of claim 16 , wherein the head element is configured to move toward the medical device such that the one or more hook elements are aligned with one or more eyelets on the medical device.

19. 1. A medical device deployment system for deploying a medical device, the medical device deployment system comprising: a medical device delivery apparatus having a head element, one or more hook elements, at least one control loop, and a medical device; the head element is located at a proximal end of the medical device delivery apparatus; the head element is configured to extend through and protrude proximally from the medical device; the head element having one or more hook elements of the medical device delivery apparatus projecting radially outward and forwardly toward a proximal end of the head element; the one or more hook elements engage a control loop that is coupled to the medical device; one end of the one or more hook elements is secured to a distal end of the head element and another end of the one or more hook elements projects proximally; The at least one control loop has a first end attached to the head element and a second end that is a free end engageable with the hook element.

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