Patent Application
20240315842
This invention relates to an implant delivery device and an implant delivery system.
Heart valves are openable and closeable flap-like structures in the organs of humans and some animals. The human heart has four valves: the aortic valve connecting the left ventricle to the aorta; the pulmonary valve connecting the right ventricle to the pulmonary artery; the mitral valve connecting the left atrium to the left ventricle; and the tricuspid valve connecting the right atrium to the right ventricle. All these valves function like one-way valves which allow blood flow in the forward direction but prevent its backward flow.
With the development of social economy and the aging of population, the incidence of valvular heart disease has increased significantly. Studies have shown that this figure has reached up to 13.3% among those 75 years or older. At present, traditional surgical treatment remains first choice for patients with severe valvular disease. However, for those with advanced ages, complications in multiple organs, a history of thoracotomy or poor heart functions, the traditional surgical approach is associated with high risk and high mortality or even precludes some patients.
Transcatheter valve replacement usually makes use of a venous vascular access and often requires controllable bending of a delivery device at a large angle after it is inserted into the heart. For example, tricuspid valve replacement may involve inserting a delivery device through the inferior vena cava into the right atrium. This requires the device to be bendable at a large angle within a narrow space in a controlled manner. Conventional delivery devices can barely meet this requirement due to their limited controllable bending angles.
It is an object of the present invention to overcome the problem of limited controllable bending angles associated with existing delivery devices by presenting an implant delivery device and an implant delivery system.
To this end, according to a first aspect of the present invention, there is provided an implant delivery device comprising a delivery assembly, a first flexible catheter and a second flexible catheter,
Optionally, in the implant delivery device, the delivery assembly may comprise a forward-backward driving unit and a loading unit,
Optionally, in the implant delivery device, the forward-backward driving unit may comprise a first delivery catheter and a second delivery catheter, and the loading unit may comprise a first loading tube and a second loading tube,
Optionally, in the implant delivery device, a radial outer dimension of the first loading tube may be greater than the radial inner dimension of the first flexible catheter and may be not greater than a radial outer dimension of the first flexible catheter.
Optionally, in the implant delivery device, the radial outer dimension of the second loading tube may be equal to the radial outer dimension of the first flexible catheter.
Optionally, in the implant delivery device, each of the first and second delivery catheters and the first and second flexible catheters may be a double-layer catheter, and wherein a braid wire is provided between the double-layer.
Optionally, in the implant delivery device, both the first and second loading tubes may be double-layer tubes.
Optionally, in the implant delivery device, the loading unit may further comprise a stent holder, wherein the stent holder is fixedly coupled to the loading unit and is used to engage with attachment lugs of the implant.
Optionally, the implant delivery device may further comprise a third delivery catheter, which is movably inserted in the delivery assembly along the axial direction of the first flexible catheter.
To the above end, according to a second aspect of the present invention, there is provided an implant delivery system comprising the implant delivery device as defined above and a driving device coupled to a proximal end of the delivery device. The driving device is configured to drive the first and second flexible catheters to bend respectively.
In summary, the present invention provides an implant delivery device and an implant delivery system. The implant delivery device includes a delivery assembly, a first flexible catheter and a second flexible catheter. At least a part of the delivery assembly is movably inserted in the first flexible catheter along an axial direction thereof, and both the first flexible catheter and the delivery assembly are movably inserted in the second flexible catheter along an axial direction thereof and are configured to protrude out of the second flexible catheter from its distal end. The first and second flexible catheters are configured to bend independently. The delivery assembly changes its direction of extension when bent shapes of the first and second flexible catheters vary.
With this arrangement, the first flexible catheter is movably inserted in the second flexible catheter, and the first and second flexible catheters may bend independently. Thus, through section-wise bending of these flexible catheters, a large controllable bending angle can be achieved, solving the problems of difficult controllable bending and limited controllable bending angles associated with conventional delivery devices. As a result, implant release can be achieved in a narrow space in a safe and accurate manner, reducing the chance of paravalvular leakage and other issues that may arise from inaccurate release during surgery.
Those of ordinary skill in the art would appreciate that the accompanying drawings are provided to facilitate a better understanding of the present invention and do not limit the scope thereof in any sense, in which:
In these figures,
Objects, advantages and features of the present invention will become more apparent upon reading the following more detailed description of the present invention with reference to the accompanying drawings. Note that the figures are provided in a very simplified form not necessarily drawn to exact scale and for the only purpose of facilitating easy and clear description of the embodiments. In addition, structures shown in the figures are usually a part of actual structures. In particular, as the figures tend to have distinct emphases, they are often drawn to different scales.
As used herein, the singular forms “a”, “an” and “the” include plural referents, unless the context clearly dictates otherwise. As used herein, the term “or” is generally employed in the sense of “and/or”, “several” is generally employed in the sense of “at least one” and “at least two” is generally employed in the sense of “two or more”, unless the context clearly dictates otherwise. Additionally, the use of the terms “first”, “second” and “third” herein is intended for illustration only and is not to be construed as denoting or implying relative importance or as implicitly indicating the numerical number of the referenced item. Accordingly, defining an item with “first”, “second” or “third” is an explicit or implicit indication of the presence of one or at least two of the items. As used herein, the term “proximal end” generally refers to an end closer to an operator, and the term “distal end” generally refers to an end closer to a lesion in a patient. The terms “one end” and “the other end”, as well as “proximal end” and “distal end”, are generally used to refer to opposite end portions including the opposite endpoints, rather than only to the endpoints. The terms “mounting”, “coupling” and “connection” should be interpreted in a broad sense. For example, a connection may be a permanent, detachable or integral connection, a direct or indirect connection with one or more intervening media, or an internal communication or interaction between two units. As used herein, when an unit is referred to as being “disposed on” another unit, this is generally intended to only mean that there is a connection, coupling, engagement or transmission relationship between the two units, which may be either direct or indirect with one or more intervening units, and should not be interpreted as indicating or implying a particular spatial position relationship between the two units, i.e., the unit may be located inside, outside, above, under, beside, or at any other location with respect to the other unit, unless the context clearly dictates otherwise. Those of ordinary skill in the art can understand the specific meanings of the above-mentioned terms herein, depending on their context.
The present invention seeks to overcome the problem of limited controllable bending angles associated with existing delivery devices by presenting an implant delivery device and an implant delivery system.
This invention will be described below with reference to the accompanying drawings.
Reference is now made to
However, as shown in
On the basis of the above analysis, in embodiments of the present invention, there is provided an implant delivery device 10 suitable for use with various prosthetic valve stents. Referring to
Referring to
The following description is set forth with reference to
The loading section 084 is configured to be connected with the delivery device 10, ensuring that the prosthetic tricuspid valve stent 08 is maintained stationary with respect to the delivery device 10 during loading of the valve into the delivery device 10, release and separation of the valve from the delivery device 10 and movement of the valve being loaded in the delivery device 10 within the patient's body. The loading section 084 is provided with connecting structures for connecting it to the delivery device 10, such as attachment lugs 085 (see
Optionally, the stent 081 may be made of, for example, nitinol, a titanium alloy, a cobalt-chromium alloy, MP35n, 316 stainless steel, L605, Phynox/Elgiloy, a platinum-chromium alloy, or another biocompatible metal known to those skilled in the art. Optionally, the stent 081 may be alternatively made of an elastic or plastically deformable material, such as a balloon expandable material, or a shape memory alloy which can transition in response to temperature changes between a collapsed configuration for delivery and an expanded or unfolded configuration. Preferably, the stent 081 is fabricated by cutting a nickel-titanium alloy tube with an outer diameter of 5-15 mm. The stent 081 may have a final diameter chosen according to the actual demand.
The valve includes at least two prosthetic leaflets, which may be made of, for example, animal pericardium or another biocompatible polymeric material. Each prosthetic leaflet is directly or indirectly attached to the stent 081 firmly at one end and free at the other end. During operation of the valve, the prosthetic leaflets open and close the blood flow passageway in place of the native leaflets of the tricuspid valve.
The skirt covers the inner and/or outer surface(s) of the stent 081, providing a sealing effect which ensures one-way blood flow from an inflow end to outflow end of the stent. The skirt may be made of, for example, pericardium or another biocompatible polymeric material commonly used in the art, such as polyethylene terephthalate (PET), polytetrafluoroethylene (PTFE). However, the present invention is not limited to any particular material of the skirt. It is to be noted that the above-discussed prosthetic tricuspid valve stent 08 is merely a non-limiting example of the implant, and those skilled in the art can understand and modify its structure and operating mechanism based upon common general knowledge in the art. In some other embodiments, those skilled in the art may select other suitable implant, such as the prosthetic mitral valve disclosed in Chinese Patent Publication No. CN204709077U or the prosthetic aortic valve disclosed in Chinese Patent Publication No. CN104000672A. The entire contents of these applications are hereby incorporated by reference herein. It would be understood that the delivery device 10 of this embodiment is also applicable to other implants such as prosthetic mitral valves and prosthetic aortic valves, and the present invention is not limited in this regard.
The implant delivery device 10 of this embodiment is further described below with reference to
Referring to
Referring to
The following description is set forth in the context of all the first delivery catheter 141, the second delivery catheter 142 and the first flexible catheter 11 being implemented as round tubes as an example. The second delivery catheter 142 has an inner diameter greater than an outer diameter of the first delivery catheter 141, and inner surface of the distal end of the first delivery catheter 141 is adhesively bonded to the stent holder 153. Once the stent holder 153 is attached to the implant, as a result of proximal movement of the first delivery catheter 141 (e.g., to the right in
Referring to
The following description is set forth with reference to
In the embodiment shown in
A comparison is drawn between the embodiments shown in
Further, a radial outer dimension of the first loading tube 151 is greater than the radial inner dimension of the first flexible catheter 11 and is not greater than a radial outer dimension of the first flexible catheter 11. With the radial outer dimension of the first loading tube 151 being greater than the radial inner dimension of the first flexible catheter 11, a distal space of the first flexible catheter 11 can be fully used. Moreover, with the radial outer dimension of the first loading tube 151 being not greater than the radial outer dimension of the first flexible catheter 11, an excessively large outer diameter of the first loading tube 151, and hence an excessively large outer diameter of the second loading tube 152, can be avoided, dispensing with the need to increase the inner diameter of the second flexible catheter 12. Preferably, the second loading tube 152 has the same outer diameter as the first flexible catheter 11, while the outer diameter of the first loading tube 151 is slightly greater than the inner diameter of the first flexible catheter 11. With this arrangement, outer surfaces of the second loading tube 152 and the first flexible catheter 11 will be flush with each other, allowing the second flexible catheter 12 to have a relatively small inner diameter.
It would be appreciated that, while the first delivery catheter 141, the second delivery catheter 142, the first loading tube 151 and the second loading tube 152 have been described in the above embodiment as round tubes, the present invention is not so limited. In practice, those skilled in the art may replace one or more of them with tubes having other cross-sectional shapes, such as oblong tubes, without departing from the scope of the present invention. Optionally, both the first delivery catheter 141 and the second delivery catheter 142 are double-layer catheters, and a braid wire is sandwiched between the two layers. In this case, controllable bending of the first delivery catheter 141 and the second delivery catheter 142 can be achieved in an active manner to make adjustments to their distal bent shapes by manipulating the proximal driving device. Preferably, both the first loading tube 151 and the second loading tube 152 are double-layer tubes. The first loading tube 151 may be of the same structure and fabricated from the same material as the first delivery catheter 141 and differ therefrom only in having a different diameter. The second loading tube 152 may be of the same structure and fabricated from the same material as the second delivery catheter 142 and differ therefrom only in having a different diameter.
In an exemplary embodiment, inner layers of the first delivery catheter 141 and the first loading tube 151 may be made of a material selected from, for example, PE, PP, PI, PEEK, Pebax, PA, TPU or PC, and their outer layers may be made of a material selected from, for example, PE, PP, PI, PEEK, Pebax, PA11, PA12, TPU or PC. The first loading tube 151 is preferred to have an inner diameter lying between 7 mm and 9 mm, and the first delivery catheter 141 is preferred to have an inner diameter lying between 6 mm and 8 mm. The inner and outer layers of the second delivery catheter 142, the second loading tube 152, the first flexible catheter 11 and the second flexible catheter 12 may be made of at least one selected from PE, PP, PI, PEEK, Pebax, PA11, PA12, TPU and PC. It would be appreciated that the second delivery catheter 142, the second loading tube 152, the first flexible catheter 11 and the second flexible catheter 12 may be made of either the same or different materials. Moreover, the inner and outer layers of each of the second delivery catheter 142, the second loading tube 152, the first flexible catheter 11 and the second flexible catheter 12 may be made of either the same or different materials. The second loading tube 152 is preferred to have an inner diameter lying between 8 mm and 11 mm, and the inner diameter of the second delivery catheter 142 is preferred to lie between 6 mm and 9 mm. The inner diameter of the first flexible catheter 11 is preferred to lie between 8 mm and 11 mm, and the inner diameter of the second flexible catheter 12 is preferred to lie between 9 mm and 12 mm. The second flexible catheter 12 is preferred to have an outer diameter lying between 10 mm and 13 mm. Further, in each of the double-layer first delivery catheter 141, double-layer second delivery catheter 142, double-layer first loading tube 151, double-layer second loading tube 152, double-layer first flexible catheter 11 and double-layer second flexible catheter 12, the braid wire provided between the two layers may be chosen as a polymeric wire made of PA or PET, or as a metallic wire made of SS304 or SS316 stainless steel or the like. The braid wire is preferred to have a diameter lying between 0.1 mm and 1 mm. It would be appreciated that the materials and dimensions of the first delivery catheter 141, the second delivery catheter 142, the first loading tube 151, the second loading tube 152, the first flexible catheter 11 and the second flexible catheter 12 described in the above exemplary embodiment is merely for illustration, and the present invention is not limited to any particular materials or dimensions of these components. Those skilled in the art can modify the materials and dimensions of the tubes to adapt them to practical needs.
Preferably, the delivery device 10 further includes a third delivery catheter 143, which is movably inserted in the delivery assembly along the axial direction of the first flexible catheter 11. More particularly, the third delivery catheter 143 may be movably inserted in the first delivery catheter 141 along the axial direction of the first flexible catheter 11. The third delivery catheter 143 is configured for passage of a guidewire therethrough and for guidance of advancement and retraction of the guidewire during delivery. In an exemplary embodiment, the third delivery catheter 143 is a single-layer catheter made of a material selected from PE, PP, PI, PEEK, Pebax, PA11, PA12, TPU, PC and the like, and the present invention is not particularly limited in this regard. The third delivery catheter 143 has an inner diameter preferred to lie between 2 mm and 6 mm.
Steps in a process for implanting the prosthetic tricuspid valve stent 08 using the delivery device 10 of the present embodiment are described below as an example.
In step 1, referring to
In step 2, referring to
In step 3, the prosthetic tricuspid valve stent 08 is released. A distal portion of the delivery assembly is adjusted in position so that the prosthetic tricuspid valve stent 08 is aligned with the target site. After that, the first delivery catheter 141 is maintained axially stationary, and the second delivery catheter 142 is proximally retracted, releasing the flange section 082 of the prosthetic tricuspid valve stent 08 from the second loading tube 152. The flange section 082 then radially expands and anchors to the annulus of the native tricuspid valve. Afterwards, the second delivery catheter 142 is further retracted, releasing the middle section 083 of the prosthetic tricuspid valve stent 08 from the second loading tube 152. Subsequently, the first delivery catheter 141 is proximally retracted to detach the attachment lugs 085 from the stent holder 153, completing the release of the prosthetic tricuspid valve stent 08.
The prosthetic tricuspid valve stent 08 can be retrieved by steps similar to the above implantation and release steps. First of all, the delivery device 10 is inserted into the right atrium through the inferior vena cava. The first flexible catheter 11 and the second flexible catheter 12 are then successively controllably bent, and the distal portion of the delivery assembly is adjusted in position so that it is aligned with the prosthetic tricuspid valve stent 08. The first delivery catheter 141 is then distally pushed, engaging the stent holder 153 with the attachment lugs 085 of the prosthetic tricuspid valve stent 08. Subsequently, the prosthetic tricuspid valve stent 08 is loaded into the second loading tube 152 by distally pushing the second delivery catheter 142 and proximally retracting the first delivery catheter 141. The delivery device 10 is then withdrawn, completing the retrieval of the prosthetic tricuspid valve stent 08.
In this embodiment, there is also provided an implant delivery system, which includes the implant delivery device 10 as defined above and a driving device (not shown) coupled to a proximal end of the delivery device 10. The driving device is used to drive the first flexible catheter 11 and the second flexible catheter 12 to bend. The driving device may be, for example, a handle or another component. It may be coupled to both the braid wires in the first flexible catheter 11 and the second flexible catheter 12 so as to be able to drive and cause bending of the first flexible catheter 11 and the second flexible catheter 12. In addition, the driving device may be further used to control and drive bending of the first delivery catheter 141 and the second delivery catheter 142 so as to enable positional adjustments to the distal end of the delivery assembly. These skilled in the art can configure the structure of the driving device based on common general knowledge in the art, and further description thereof is omitted herein. Since the delivery system incorporates the above-discussed delivery device 10, it has the benefits that the delivery device 10 provides.
In summary, the present invention provides an implant delivery device and an implant delivery system. The implant delivery device includes a delivery assembly, a first flexible catheter and a second flexible catheter. At least a part of the delivery assembly is movably inserted in the first flexible catheter along an axial direction thereof, and both the first flexible catheter and the delivery assembly are movably inserted in the second flexible catheter along an axial direction thereof and configured to protrude out of the second flexible catheter from its distal end. The first and second flexible catheters are configured to bend independently. The delivery assembly changes its direction of extension when bent shapes of the first and second flexible catheters vary. With this arrangement, the first flexible catheter is movably inserted in the second flexible catheter, and the first and second flexible catheters are bendable independently. Thus, through section-wise bending of these flexible catheters, a large controllable bending angle can be achieved, solving the problems of difficult controllable bending and limited controllable bending angles associated with conventional delivery devices. As a result, implant release can be achieved in a narrow space in a safe and accurate manner, reducing the chance of paravalvular leakage and other issues that may arise from inaccurate release during surgery.
It is to be noted that the foregoing several embodiments are not limited to be used alone but can be combined. The present invention is not limited in this regard. The description presented above is merely that of some preferred embodiments of the present invention and does not limit the scope thereof in any sense. Any and all changes and modifications made by those of ordinary skill in the art based on the above teachings are intended to fall within the scope of the present invention.
| Number | Date | Country | Kind |
|---|---|---|---|
| 202110672196.9 | Jun 2021 | CN | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/CN2021/113828 | 8/20/2021 | WO |
