Rotationally torquable endovascular device with actuatable working end

An endovascular device including a hollow shaft having a proximal end and a distal end, and sized for insertion into a blood vessel, may be provided. The endovascular device may also include a control line configured to extend through the hollow shaft and an actuatable working portion situated distally from the distal end of the hollow shaft and configured to receive an actuation force transmitted via the control line. The endovascular device may further include an actuator configured to exert the actuation force on the control line to cause relative movement between the control line and the hollow shaft and to actuate the working portion. The endovascular device may also include a rotation restriction barrier configured to substantially impede the control line from rotating relative to the working portion, while permitting relative axial movement between the control line and the hollow shaft.

FIELD

This disclosure relates generally to endovascular devices.

SUMMARY

Endovascular devices may include a hollow elongated shaft connected to a working portion at its distal end, and an elongated control element which may be connected to a distal tip of the working portion. The control wire may be connected to a proximal actuator which can create a relative axial motion between the control wire and the working portion and the shaft. When the control wire is pulled by the actuator, for example, the distal tip of the working member is also pulled and a relative motion at the distal tip can be achieved. One example of such an endovascular device may include a wire mesh that expands when the control wire is pulled. Another example may include a guidewire tip which bends when the control wire is pulled.

An endovascular hollow shaft may be made in a number of different ways. For example, a hollow shaft may be made from a hollow metallic tube or a cable of wires. As another example, the hollow shaft may be made from layers of polymers such as polytetrafluoroethylene (PTFE) and PEBAX (available from Arkema) or with a combination of a reinforcement braid or coil and such polymers. As yet another example, an endovascular shaft may be made from a combination of any of the above. For example, the proximal 100 cm portion may be made from a metallic tube, then 30 cm of PTFE coated cable of wires can be bonded, and finally a single wire coil can be bonded to create a supple distal section.

The control wire may include several wires that collectively form a control cable. The control wire, for example, may be made of metal wires or materials, polymers or other materials. The control wires may also be made from a combination of the materials and components listed above, and may include different sections with different stiffness. In one example, the control wire may be made from a single wire which is grinded at its distal section to achieve flexibility of the wire.

The design of endovascular devices which incorporate a control wire, operate to help allow a physician to transfer a movement in a proximal actuator or handle to a distal working portion. The physician may control the handle outside of a patient's body with the working portion acting at a target location in the patient. While this design allows for the transmission of axial forces from the proximal handle to the distal working portion, because the elongated shaft is typically round and hollow and the control wire is hollow, it may be limited in its ability to transmit radial movement from the proximal to the distal end.

This limitation may be caused, for example, in view of the control wire and elongated shaft being connected only at the distal end. As a result, rotating the elongated shaft in its proximal part does not necessarily result in rotating of the control wire due to some of the radial torque transmitted to the shaft elastic deformation. In an exemplary endovascular device of the present disclosure, a fixture may enable transmission of the radial force of the elongated shaft to the control wire with a 1:1 ratio. This may be achieved, for example, by preventing the axial rotation between the control wire and the elongated shaft without preventing the axial movement between these two members.

Preventing axial rotation between the control wire and the elongated shaft without preventing the axial movement between these two members may be achieved, for example, by deforming at least a portion of the control wire and making at least a portion of the inner cross section of the round elongated shaft non-round, respectively. In accordance with exemplary embodiments of an endovascular device, there may be an overlap between the two rectangular portions even during axial movement of the control wire compare to the elongated shaft.

The disclosed embodiments may include an endovascular device including a hollow shaft having a proximal end and a distal end, and sized for insertion into a blood vessel. The endovascular device may also include a control line having a proximal end and a distal end, and extending through the hollow shaft. The endovascular device may also include an actuatable working portion located beyond the distal end of the hollow shaft, and configured to receive an actuation force transmitted via the distal end of the control line. The endovascular device may further include an actuator configured to exert the actuation force on the proximal end of the control line, to thereby cause relative movement between the control line and the hollow shaft and to actuate the working portion. The endovascular device may also include at least one control line rotation restrictor integral with the control line and located within the hollow shaft; and at least one rotation restrictor element associated with at least one of the hollow shaft and the working portion, and configured to engage with the control line rotation restrictor to thereby substantially impede the control line from rotating relative to the working portion, while permitting relative axial movement between the control line and the hollow shaft.

In another embodiment, the at least one control line rotation restrictor of the endovascular device includes at least one deformation of the control line. The at least one deformation may include at least one flattened portion of the control line.

In another embodiment, the control line of the endovascular device includes a region of round cross-section adjacent to the at least one deformation.

In another embodiment, the hollow shaft of the endovascular device may be formed of at least one wound wire.

In another embodiment, the hollow shaft of the endovascular device may include a cable formed of a plurality of wires.

In another embodiment, the working portion of the endovascular device includes a bendable tip formed of a coiled wire section beyond the distal end of the hollow shaft.

In another embodiment, the coiled wire section of the endovascular device has a flexibility greater than a flexibility of the hollow shaft.

In another embodiment, the actuator of the endovascular device includes a control handle configured to transmit at a ratio of approximately 1:1, rotational force exerted on the control handle to rotational force on the working portion.

In another embodiment, the at least one rotation restriction barrier of the endovascular device may include at least one deposit of material within at least one of the hollow shaft and the working portion, and wherein the deposit of material narrows a portion of a channel in at least one of the hollow shaft and the working portion. The deposited material may be a polymer.

In another embodiment, the at least one rotation restriction barrier of the endovascular device may include a first rotation restriction barrier in the hollow shaft and a second rotation restriction barrier in a channel of the working portion.

In another embodiment, the at least rotation restriction barrier of the endovascular device may include a first rotation restriction barrier in the hollow shaft and a second rotation restriction barrier in the coiled wire section.

In another embodiment, the control handle of the actuator is configured to enable pulling of the control line, to thereby cause the coiled section to bend and to transmit rotational torque to the bent coiled section when the control handle is rotated.

In another embodiment, the control line rotation restrictor and the rotation restriction barrier of the endovascular device may each have an axial length, such that when axially moved relative to each other, the control line rotation restrictor and the rotation restrictor element remain engaged.

In another embodiment, the endovascular device may be configured to permit a user to exert an applied relative rotational force of between the distal tip and a control line to the control handle, and the control line rotation restrictor and the rotation restriction barrier are configured to transmit the applied force to the working portion without substantial slippage between the control line rotation restrictor and the rotation restriction barrier.

In another embodiment, the hollow shaft of the endovascular device includes a hollow metallic tube and the working portion includes a coiled wire distal to the hollow metallic tube.

In another embodiment, the hollow shaft of the endovascular device includes a polymeric tube and the working portion includes a coiled wire distal to the polymeric tube.

In another embodiment, the control line of the endovascular device is formed of a single wire and wherein the at least one control line rotation restrictor includes at least one deformation in a cross-sectional area of the single wire.

In another embodiment, the at least one control line rotation restrictor of the endovascular device includes at least a first deformation in an elongated region of the control line within the hollow shaft, and at least a second deformation of the control line in an elongated region of the working portion.

Annotations appearing in the figures are exemplary only, and are not restrictive of the invention as claimed.

DETAILED DESCRIPTION

Reference will now be made in detail to the present embodiments (exemplary embodiments) of the disclosure, examples of which are illustrated in the accompanying drawings.

FIG. 1illustrates a control line101(e.g., a control wire) of an exemplary endovascular device in accordance with the disclosure, which may be deformed or flattened in two zones that form control line rotation restrictors101-3, and may be round in other areas along its axis101-2.FIG. 2illustrates an exemplary endovascular device201using control line101in accordance with the disclosure. (Solely to illustrate the position of zone101-2and control line rotation restrictor101-3in endovascular device201, with the understanding that control line101is part of endovascular device201,FIG. 2also separately depicts control line101ofFIG. 1, with control line rotation restrictors101-3and zone101-2generally aligned to endovascular device201.) As shown inFIG. 2, endovascular device201may also include an elongated shaft204which may include a tube205, a cable of wires206, and a working portion207(e.g., a single wire coil as shown inFIG. 2). A distal tip210of the elongated shaft204may be attached to control line101, for example. At a proximal end of the elongated shaft204, the control line101may be connected to a slider211of an actuator209(e.g., a handle as shown inFIG. 2), with the elongated shaft204connected to the actuator209to facilitate the relative movement. (InFIG. 2, actuator209is not depicted to the same scale as that of elongated shaft204.) In accordance with at least some embodiments, two rotation restriction barriers208(e.g., polymers) may be inserted between the elongated shaft204and the control line101to prevent the radial movement between the control line101and the elongated shaft204.

Consistent with the embodiment shown inFIGS. 9 and 10, in at least some embodiments of an exemplary endovascular device of the disclosure, the cable of wires206and the working portion207of the elongated shaft204may be elliptical. This elliptical shape resists relative rotation of the elongated shaft204and the control line101, enabling torqueing of the device. Alternatively, other non-symmetrical shapes (e.g., cross-sections) may be employed, consistent with the invention to resist rotation and to permit torqueing.

At least some embodiments of an exemplary endovascular device of the disclosure may encompass a fixture enabling transmission of a radial force of the elongated shaft204to the control line101with 1:1 ratio. This may be achieved, for example, by preventing axial rotation between the control line101and the elongated shaft204without preventing the axial movement between the control line101and the elongated shaft204. And such axial rotation prevention (without axial movement prevention) may be achieved, for example, by deforming at least a portion of the control line101and making at least a portion of the inner cross section of the round elongated shaft204non-round, respectively. For example, there may be an overlap between the two rectangular (or flattened) portions that form control line rotation restrictors101-3even during axial movement of the control line101compared to the elongated shaft204.

A control line101with at least some flat or rectangular section or sections may be achieved by, for example, selectively pressing the control line101, by adhesion of additional materials to form a non-round shape, or by other means.

Achieving a non-round inner cross section may be achieved, for example, by attaching rectangular shaped rotation restriction barriers208to an inner wall of the elongated shaft204. As another example, a rotation restriction barriers208may include a polymer inserted through the wire cable to create a non-round cross section. The polymer of the rotation restriction barriers208may be heated and inserted through holes in the wall of the elongated shaft204and shaped as needed by a rectangular mandrel.

As shown inFIG. 3, which illustrates an inner cross section A-A of a section of exemplary endovascular device201, the control line101may be made from 0.14 mm Nitinol wire. A distal tip of the control line101may be gradually grinded to an outer diameter of about 70 um. The elongated shaft204may be made from a 130 cm Nitinol tube with an inner diameter of 0.18 mm which may be bonded to a PTFE covered cable of ten 70 um Nitinol wires and the distal section may be a single 70 um wire which may be coiled.

As shown inFIG. 4, which illustrates an inner cross section B-B of a section of exemplary endovascular device201, the control line101may be pressed to create flat sections that form control line rotation restrictors101-3of about 0.16 mm×0.12 mm of 30 mm of length. Using a rectangular mandrel, a rotation restriction barrier208(e.g., a polymer) may be inserted through the wire cable206to create a non-round cross section in areas that overlap the non-round sections of the control line101. As a result, relative axial movement between the control line101and the elongated shaft204may be maintained while the axial rotation between the control line101and the elongated shaft204(which includes cable206) may be prevented.

FIG. 5illustrates an inner cross section C-C of a section of exemplary endovascular device201, similar to cross section B-B ofFIG. 4. Again, as a result, relative axial movement between the control line101and the elongated shaft204may be maintained while the axial rotation between the control line101and the elongated shaft204(which includes working portion207) may be prevented.

In a further embodiment,FIG. 6illustrates a control line601(e.g., a control wire) of an exemplary endovascular device in accordance with the disclosure, which may be deformed or flattened in a zone that forms control line rotation restrictor601-3, and may be round in other areas along its axis601-2.FIG. 7illustrates an exemplary endovascular device701using control line601in accordance with the disclosure. (Solely to illustrate the position of zone601-2and control line rotation restrictor601-3in endovascular device701, with the understanding that control line601is part of endovascular device701,FIG. 7also separately depicts control line601ofFIG. 6, with control line rotation restrictor601-3and zone601-2generally aligned to endovascular device701.) As shown inFIG. 7, endovascular device701may also include an elongated shaft704which may include a tube705, a cable of wires706, and a working portion707(e.g., a single wire coil as shown inFIG. 7). A distal tip710of the elongated shaft704may be attached to control line601, for example. At a proximal end of the elongated shaft704, the control line601may be connected to a slider211of an actuator209, with the elongated shaft704connected to the actuator209to facilitate the relative movement. (InFIG. 7, actuator209is not depicted to the same scale as that of elongated shaft704.)

FIG. 8illustrates an inner cross section D-D of a section of exemplary endovascular device701. The control line601may be made from 0.14 mm Nitinol wire. A distal tip of the control line601may be gradually grinded to an outer diameter of about 70 um. The elongated shaft704may be made from a 130 cm Nitinol tube with an inner diameter of 0.18 mm which may be bonded to a PTFE covered cable of ten 70 um Nitinol wires and the distal section may be a single 70 um wire which may be coiled.

As shown inFIGS. 9 and 10, which illustrates inner cross sections E-E and F-F of a section of exemplary endovascular device701, the control line601may be pressed to create flat sections that form control line rotation restrictors101-3of about 0.16 mm×0.12 mm of 30 mm of length. As mentioned above, inFIGS. 9 and 10, the cable of wires706and the working portion707of the elongated shaft704may be elliptical. This elliptical shape resists relative rotation of the elongated shaft704and the control line601, enabling torqueing of the device; that is, the elliptical cable of wires706and working portion707may form a rotation restriction barrier in some embodiments. Alternatively, other non-symmetrical shapes (e.g., cross-sections) may be employed, consistent with the invention to resist rotation and to permit torqueing.

In other embodiments, a single wire coil may be provided, extending from a multi-wire cable with a control wire that runs through the core of both. This enables the control wire to steer the more flexible coiled end of the coil, without causing the multi-wire cable to appreciably bend.