Disclosure of Invention
The application aims to provide a ventricular assist device for treating ventricular wall tumors, which can be tightly attached to the ventricular wall so as to reduce or even solve the problem of residual leakage after operation and reduce the risk of thrombus.
The technical scheme provided by the application is as follows:
A ventricular assist device useful for ventricular wall tumors, comprising:
a bracket;
The support is provided with a first end and a second end which are opposite, the first end of the support is attached with a high polymer film, the second end of the support is provided with a base, a stress part is formed between the first end and the second end, when the stress part is stressed and contracted in the radial direction, the support stretches along the axial direction, and,
The edge of the high polymer film is provided with a skirt edge, one end of the skirt edge, which is far away from the high polymer film, is reversely adhered to the high polymer film, and when the bracket enters the ventricle, the part, which is reversely adhered to the high polymer film, of the skirt edge is separated from the high polymer film and is adsorbed on the ventricular cavity wall.
In some embodiments, the skirt is made of polytetrafluoroethylene material and is temporarily and reversely adhered to the side of the polymeric membrane facing away from the second end of the stent by a hydrolytic adhesive.
In some embodiments, the stent comprises at least three alloy rings;
The alloy ring comprises a first supporting part and a second supporting part, wherein the first supporting part is provided with two ends in the axial direction of the first supporting part, the second supporting part is of an arc-shaped structure, and the two ends of the first supporting part are respectively connected with the two ends of the second supporting part in the length direction;
Each first supporting part is overlapped with two first supporting parts, all the first supporting parts form a first end of the bracket, each second supporting part is overlapped with two second supporting parts, and one end, deviating from the first supporting parts, of all the second supporting parts forms a second end of the bracket;
When the support is in an original state, the first support part is in a straight structure and is in a straight state, and when the second support part is radially stressed and contracted, the first support part is changed from the straight state to an arched state.
In some embodiments, the ventricular assist device useful for a ventricular tumor further comprises:
a loading head for interfacing with an external transport system;
The alloy rings are three in number, a mounting space is formed by surrounding the first supporting portions, the loading head is arranged on the first supporting portions and located in the mounting space, and one end of the loading head, deviating from the second end of the support, does not protrude out of the high-molecular polymer film.
In some embodiments, the alloy ring is made of round solid nickel titanium alloy wire with uniform diameter, or,
The alloy ring is made of round solid nickel-titanium alloy wires with gradually changed diameters, and the diameter of the part of the round solid nickel-titanium alloy wires close to the first end is smaller than that of the part of the round solid nickel-titanium alloy wires close to the second end, or,
The alloy ring is made of flat solid nickel-titanium alloy strips with consistent width, or,
The alloy ring is made of a flat solid nickel-titanium alloy strip with gradually changed width, and the diameter of the part of the flat solid nickel-titanium alloy strip close to the first end is not larger than that of the part of the flat solid nickel-titanium alloy strip close to the second end.
In some embodiments, the polymeric film comprises a first film and a second film;
the first film is positioned on one side of the first supporting part facing away from the second end, and the second film is positioned on one side of the first supporting part facing towards the second end;
the skirt edge is arranged at the edge of the first film.
In some embodiments, the first film comprises a micronanofiber layer, a first polytetrafluoroethylene layer, a first polyethylene terephthalate layer, and a second polytetrafluoroethylene layer in that order in the first end to the second end;
The second film comprises a third polytetrafluoroethylene layer, a second polyethylene terephthalate layer and a fourth polytetrafluoroethylene layer in sequence from the first end to the second end.
In some embodiments, the micro-nanofiber layer is a guiding fiber structure arranged in a radial manner, and the distance between two adjacent fiber filaments in the micro-nanofiber layer is not more than 100 micrometers.
In some embodiments, the second support portion is provided with an anchoring barb for securing the bracket.
In some embodiments, the base is made of a silicone material, or the base is made of a silicone material and a developing material.
The application has the technical effects that:
1. In the application, the support is provided with a stress part, when the stress part is stressed and contracted in the radial direction, the support stretches along the axial direction, and when the external force disappears, the stress part is not stressed in the radial direction, and the support returns to the original state. In this way, the stent is able to spontaneously adapt to the systolic and diastolic movements of the heart. In addition, the edge of the high polymer membrane attached to the first end of the bracket is provided with the skirt edge, and when the bracket enters the ventricle, the skirt edge can be adsorbed on the wall of the ventricle cavity, so that the ventricular assist device can be tightly attached to the wall of the ventricle cavity, thereby reducing or even solving the problem of residual leakage after operation and reducing the risk of thrombus.
2. In the application, the bracket comprises three alloy rings, the first supporting parts of the three alloy rings are overlapped with each other, and the second supporting parts of the three alloy rings are overlapped with each other, so that a bracket structure similar to a cage can be formed, the characteristics of high deformation and quick reset exist, the left ventricular expansion tumor can be isolated, the residual leakage after operation is reduced, the ventricular contraction can be assisted, and the mechanical compensation of heart pump failure can be realized. Especially when the alloy ring is made of round solid nickel-titanium alloy wires with gradually changed diameters or flat solid nickel-titanium alloy strips with gradually changed widths, the first supporting part can have larger deformation proportion and faster deformation speed so as to adapt to the rapid contraction and relaxation of the left chamber wall cardiac muscle.
3. In the application, the high polymer film attached to the first end of the bracket comprises a first film, wherein the outermost layer of the first film is a micro-nano fiber layer, the micro-nano fiber layer is in a guiding fiber structure which is radially arranged, and the distance between two adjacent fiber filaments in the micro-nano fiber layer is not more than 100 micrometers. Therefore, the dense radial fiber filaments on the micro-nano fiber layer can play a role in migration and guiding of endothelial cells on the wall surface of the ventricle, accelerate endothelialization speed and reduce thrombus and bleeding risks related to the instrument.
Drawings
The application is described in further detail below with reference to the attached drawings and detailed description:
FIG. 1 is a schematic perspective view of a ventricular assist device in a raw state according to an embodiment of the present application;
FIG. 2 is a schematic perspective view of a ventricular assist device of FIG. 1 for ventricular tumors with polymeric membranes and skirts removed;
FIG. 3 is a schematic perspective view of a ventricular assist device according to an embodiment of the present application in a radially stressed and contracted state after removing a polymeric film and a skirt;
FIG. 4 is a schematic perspective view of a skirt according to an embodiment of the present application reversely adhered to a polymeric film;
FIG. 5 is a schematic perspective view of a skirt according to an embodiment of the present application, which is not anti-adhered to a polymeric membrane;
FIG. 6 is a schematic view of an assembly of an alloy ring and a loading head provided by one embodiment of the present application;
FIG. 7 is a partial cross-sectional view of a polymeric membrane and alloy ring provided in accordance with one embodiment of the present application;
FIG. 8 is an enlarged partial schematic view of FIG. 7 at A;
FIG. 9 is a schematic perspective view of a round solid nickel titanium alloy wire of uniform diameter according to one embodiment of the present application;
FIG. 10 is a schematic perspective view of a diameter graded round solid NiTi alloy wire according to one embodiment of the present application;
FIG. 11 is a schematic perspective view of a flat solid nickel titanium alloy strip of uniform diameter according to one embodiment of the present application;
fig. 12 is a schematic perspective view of a flat solid nickel-titanium alloy strip with gradually changed diameters according to an embodiment of the present application.
Reference numerals illustrate:
100. the device comprises a bracket, 110, an alloy ring, 111, a first supporting part, 112, a second supporting part, 120, an installation space, 130 and an anchoring barb;
200. Polymer film, 210, first film, 211, micro-nano fiber layer, 212, first polytetrafluoroethylene layer, 213, first polyethylene terephthalate layer, 214, second polytetrafluoroethylene layer, 220, second film, 221, third polytetrafluoroethylene layer, 222, second polyethylene terephthalate layer, 223, fourth polytetrafluoroethylene layer;
300. a skirt edge;
400. A base;
500. A loading head;
600. round solid nickel-titanium alloy wire;
700. flat solid nickel-titanium alloy strip.
Detailed Description
In the following description, for purposes of explanation and not limitation, specific details are set forth such as the particular system architecture, techniques, etc., in order to provide a thorough understanding of the embodiments of the present application. It will be apparent, however, to one skilled in the art that the present application may be practiced in other embodiments that depart from these specific details. In other instances, detailed descriptions of well-known systems, devices, circuits, and methods are omitted so as not to obscure the description of the present application with unnecessary detail.
In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following description will explain the specific embodiments of the present application with reference to the accompanying drawings. It is evident that the drawings in the following description are only examples of the application, from which other drawings and other embodiments can be obtained by a person skilled in the art without inventive effort.
For the sake of simplicity of the drawing, the parts relevant to the present application are shown only schematically in the figures, which do not represent the actual structure thereof as a product. Additionally, in order to simplify the drawing for ease of understanding, components having the same structure or function in some of the drawings are shown schematically with only one of them, or only one of them is labeled.
In this context, it should be noted that the term "coupled" is to be interpreted in a broad sense, unless explicitly stated and defined otherwise, as being either fixedly coupled, or detachably coupled, or integrally coupled, or mechanically coupled, or electrically coupled, or indirectly coupled via an intermediate medium, for example. The specific meaning of the above terms in the present application will be understood in specific cases by those of ordinary skill in the art.
In the embodiment shown in the drawings, the indications of orientation (such as up, down, left, right, front, back, etc.) are not absolute, but rather relative, in describing the structure and movement of the various components and are not intended to limit the orientation of the product in actual use.
In addition, in the description of the present application, ordinal words such as "first," "second," and the like are merely used to distinguish between the description of the associated objects and are not to be construed as indicating or implying a relative importance or order between the associated objects.
In the prior art, left ventricular isolation devices have mostly comprised a flexible membrane that can be implanted in the ventricle in a lateral position during surgery and which is supported by an umbrella-like support. However, the tight fit between the circular diaphragm and the umbrella-shaped support and the irregular ventricular cavity wall cannot be ensured, and residual leakage after operation often occurs, so that thrombus risks are caused, and certain trouble and risks are brought to the rehabilitation of patients.
First, the presence of residual leaks may result in an increased cardiac burden. The heart is an important organ of the human body and is a driving force for blood circulation, and when a defect exists in the ventricular septum and the residual leakage exists, blood flows into the left ventricle and the right ventricle through the notch, so that the blood volume of the left ventricle is increased, and the heart burden is increased. In the long term, this condition may lead to left ventricular hypertrophy, impaired cardiac function, and even the development of heart failure.
Second, residual leakage also increases the risk of infection. The presence of residual leakage after surgical trauma can result in the heart chamber compartment failing to close completely, thereby increasing the likelihood of infection. Once the heart is infected, the patient may develop symptoms such as fever, weakness, palpitations, etc., and require long-term antibiotic treatment, which is very detrimental to the patient's recovery.
Accordingly, referring to fig. 1-5, in view of the problem of how to reduce residual leakage after surgery, the present application provides a ventricular assist device, particularly including a stent 100, that can be used for ventricular wall tumors. The bracket 100 has a first end and a second end opposite to each other, the first end is attached with the polymeric film 200, the second end is provided with a base 400, and a stress portion is formed between the first end and the second end. When the force-bearing part is radially stressed and contracted, the support 100 is axially stretched, when the external force is lost, and when the force-bearing part is not radially stressed, the support 100 is restored to the original state, and the shape of the support 100 in the original state is closest to the shape of the support 100 in diastole after being implanted into a ventricular cavity.
In this embodiment, referring to fig. 2 and 3, the transverse diameter (the dimension of the stent 100 in the direction perpendicular to the connection line between the first end and the second end) and the longitudinal diameter (the dimension of the stent 100 in the direction perpendicular to the connection line between the first end and the second end) of the stent 100 can be changed in equal proportion in opposite directions according to the change of the external force, so that the stent 100 can spontaneously adapt to the systolic and diastolic movements of the heart.
In addition, in the present embodiment, referring to fig. 1, 4 and 5, the edge of the polymeric film 200 is further provided with a skirt 300, and an end of the skirt 300 away from the polymeric film 200 is reversely adhered to the polymeric film 200. After the stent 100 enters the ventricle, the part of the skirt 300 reversely adhered to the high polymer film 200 is separated from the high polymer film 200 and is adsorbed on the ventricular cavity wall, so that the ventricular assist device provided by the application can be tightly adhered to the ventricular cavity wall, thereby effectively reducing or even solving the problem of residual leakage after operation, reducing the risk of thrombus and accelerating the rehabilitation process of a patient.
Specifically, the skirt 300 is made of polytetrafluoroethylene material and is temporarily and reversely adhered to the side of the polymeric membrane 200 facing away from the second end of the holder 100 by means of a hydrolytic adhesive. The self-dissolving time of the hydrolytic gel is about 30-60 minutes, and after the hydrolytic gel is dissolved in blood, the skirt 300 can be attached to the gap between the bracket 100 and the ventricular wall along with the pressure of blood flow, thereby being self-adsorbed on the ventricular cavity wall and reducing residual leakage after operation.
In one example embodiment, referring to fig. 1-3 and 6, the stent 100 includes at least three alloy rings 110, and each alloy ring 110 includes a first support 111 and a second support 112. Specifically, the first supporting portion 111 has two ends in the axial direction thereof, the second supporting portion 112 has an arc-shaped structure, and the two ends of the first supporting portion 111 are respectively connected to the two ends of the second supporting portion 112 in the length direction. In the original state, the first supporting portion 111 has a linear structure, and at this time, each alloy ring 110 has a flat-top and pointed-bottom semi-elliptical structure. When the parts of the second supporting portion 112 connected to the first supporting portion 111 are folded, the two ends of the first supporting portion 111 are driven by the second supporting portion 112 to approach each other, and at this time, the first supporting portion 111 arches in a direction away from the second supporting portion 112.
In this embodiment, each first supporting portion 111 overlaps two first supporting portions 111, and all the first supporting portions 111 together form a first end of the bracket 100. In contrast, each second support portion 112 overlaps two second support portions 112, and the ends of all second support portions 112 facing away from the first support portion 111 together form the second end of the bracket 100.
When the stress portion of the support 100 is stressed and contracted radially, that is, the second supporting portion 112 is stressed and contracted radially, the first supporting portion 111 is changed from a flat state (i.e., a linear structure) to an arched state at this time, and when the stress portion of the support 100 is not stressed radially, that is, the second supporting portion 112 is not stressed by force, at this time, the first supporting portion 111 is changed from the arched state to the flat state again.
The whole support 100 provided in this embodiment is of a cage-like support 100 structure, and has the characteristics of high deformation and quick reset, so that not only can the left ventricular bulge be isolated, residual leakage after operation be reduced, but also ventricular contraction can be assisted, and mechanical compensation of heart pump failure can be realized.
In the above embodiment, referring to fig. 6, the first supporting portions 111 of all the alloy rings 110 are overlapped to form a mounting space 120, and the mounting space 120 has a polygonal structure and can be used to install a loading head 500, and the ventricular assist device is abutted to the external conveying system through the loading head 500. For example, when the number of the alloy rings 110 is three, the first supporting portions 111 of the three alloy rings 110 are overlapped to form a triangular installation space 120, if the number of the alloy rings 110 is four, a quadrangular installation space 120 is formed, and if the number of the alloy rings 110 is five, a pentagonal installation space 120 is formed, which is not described in detail herein, and is within the scope of the present application.
Specifically, referring to fig. 9 and 11, the alloy ring 110 may employ a round solid nitinol wire 600 having a uniform diameter, and in this case, the round solid nitinol wire 600 has an outer diameter ranging from 0.1 to 0.8mm. In addition, the alloy ring 110 can be made of flat solid nickel titanium alloy strips 700 with uniform width, and the thickness of the flat solid nickel titanium alloy strips 700 is about 0.02-0.1mm and the width is about 0.05-0.1mm.
Of course, referring to fig. 10, in actual production, the alloy ring 110 may also be made of a round solid nitinol wire 600 with a gradually changing diameter, and the diameter of the round solid nitinol wire 600 near the first end is smaller than the diameter of the round solid nitinol wire 600 near the second end. Specifically, the diameter-graded round solid nitinol wire 600 has an outer diameter of 0.1-0.8mm near the second end and 0.05-0.5mm near the first end.
In addition, referring to fig. 12, the alloy ring 110 may be made of a flat solid nitinol strip 700 with gradually changed width, and the diameter of the portion of the flat solid nitinol strip 700 near the first end is not larger than the diameter of the portion of the flat solid nitinol strip 700 near the second end. Specifically, the width of the flat solid nickel titanium alloy strip 700 with gradually changed width is 0.05-0.1mm near the second end, the thickness is 0.02-0.1mm, the width near the first end is 0.02-0.1mm, and the thickness is 0.02-0.1mm.
When the alloy ring 110 is made of the round solid nickel-titanium alloy wire 600 with gradually changed diameter or the flat solid nickel-titanium alloy strip 700 with gradually changed width, the cage body formed by the first supporting portion 111 has a larger deformation proportion and a faster deformation speed. In this way, when the cage body formed by the second supporting parts 112 receives the ventricular wall contraction force, the deformation force generated by the myocardial contraction can be more instantaneously transferred to the cage body formed by the first supporting parts 111, and the radial deformation of the cage body formed by the first supporting parts 111 is brought. Meanwhile, when the ventricular wall cardiac muscle is converted from a contracted state to a relaxed state, the bracket 100 with a cage-shaped structure, which is made of the circular solid nickel-titanium alloy wire 600 with gradually changed diameter or the flat solid nickel-titanium alloy strip 700 with gradually changed width, can rebound more rapidly so as to adapt to the rapid contraction and relaxation of the ventricular wall cardiac muscle, and the structural arrangement is more reasonable and has strong practicability.
In one embodiment, referring to fig. 1-3 and 6, a ventricular assist device that may be used for a ventricular tumor further includes a loading head 500 for interfacing with an external delivery system. The loading head 500 is preferably in a cylindrical structure, and in this case, the number of the alloy rings 110 is preferably three, and the first supporting portions 111 of the three alloy rings 110 together enclose the installation space 120 formed in a triangular structure.
Because each triangle has an inscribed circle, the outer side wall of the loading head 500 can be fixedly connected with the three first supporting parts 111 at the same time no matter how the three alloy rings 110 are arranged, so that the structure of the ventricular assist device is more stable. Meanwhile, the cost of the ventricular assist device can be reduced to a certain extent by only adopting three alloy rings 110, and the structure is more reasonable and simple.
Specifically, the stent 100 in a "cage" configuration is interwoven with three alloy rings 110 paraxial (an axis being understood to be the central axis of the loading head 500).
In a preferred embodiment, referring to fig. 1-3, the end of the loading head 500 facing away from the second end of the holder 100 does not protrude beyond the polymeric membrane 200, i.e., the loading head 500 is integrally embedded and secured within the holder 100 in a "cage" configuration. A spiral needle penetrates the polymeric membrane 200 to connect the loading head 500 to the delivery system, and when the ventricular assist device is released in place, the spiral needle is separated from the loading head 500, and only a small pinhole remains in the polymeric membrane 200.
Illustratively, referring to fig. 7, the polymeric film 200 includes a first film 210 and a second film 220. The first film 210 is located at a side of the first supporting portion 111 facing away from the second end, the second film 220 is located at a side of the first supporting portion 111 facing toward the second end, and the first film 210 and the second film 220 are bonded by an adhesive to form the polymeric film 200.
Specifically, referring to fig. 8, the first film 210 includes a four-layer structure, from a first end to a second end, a micro-nanofiber layer 211, a first polytetrafluoroethylene layer 212, a first polyethylene terephthalate layer 213, and a second polytetrafluoroethylene layer 214 in this order, wherein the first polyethylene terephthalate layer 213 is an intermediate network structure made of polyethylene terephthalate. In contrast, the second film 220 comprises a three-layer structure, from the first end to the second end, a third polytetrafluoroethylene layer 221, a second polyethylene terephthalate layer 222 and a fourth polytetrafluoroethylene layer 223 in sequence, and the second polyethylene terephthalate layer 222 is an intermediate net structure made of polyethylene terephthalate.
At this time, the skirt 300 is provided at the edge of the first film 210, and is a continuation of the first film 210, and has a single-layer polytetrafluoroethylene structure.
Preferably, referring to fig. 4 and 5, the micro-nanofiber layer 211 on the outermost layer of the first film 210 has a guiding fiber structure arranged radially, and the distance between two adjacent fiber filaments in the micro-nanofiber layer 211 is not more than 100 micrometers. The dense radial fiber filaments can play a role in migration and guiding endothelial cells on the wall surface of a ventricle, accelerate endothelialization speed and reduce the related thrombus and bleeding risks of the instrument.
For example, referring to fig. 1 to 3, the second support 112 is provided with an anchoring barb 130, and the anchoring barb 130 is positioned at a position of the second support 112 corresponding to the maximum transverse dimension of the stent 100, and the stent 100 is fixed to the ventricle by an expansion anchoring technique. Specifically, two anchoring barbs 130 are provided on each of the second support portions 112, and all of the anchoring barbs 130 are located on the plane of maximum transverse diameter of the stent 100.
Specifically, the base 400 at the second end of the stent 100 is made of a silicone material, wherein the base 400 is preferably made of a low density silicone material to reduce metal contact stress damage due to the thinning of a portion of the diseased apex wall.
In addition, the base 400 may be mixed with developing material during the manufacturing process, i.e. the base 400 is made of silica gel material and developing material, so that the medical staff can observe the position of the ventricular assist device in surgery to determine whether the ventricular assist device is in place.
The ventricular assist device of the present application is used to assist in improving cardiac pump failure by implantation into the heart ventricle (typically the left ventricle). When in actual use, the radial artery/femoral artery is firstly taken to establish a vascular access, the vascular access is sent into the guide wire and the pigtail catheter, transvalve and left ventricular radiography is completed, the guide wire is reserved to the left ventricle, and the guide sheath is sent to the lower 1/3 of the left ventricle along the guide wire. After loading the ventricular assist device onto the delivery system and confirming its release properties in vitro, the delivery system loaded with the ventricular assist device is delivered to the left ventricular target site along the introducer sheath, and the ventricular assist device is slowly released, so that its "cage" stent 100 is fully deployed and anchored to the ventricular wall, and released after being secured. The ventricular assist device not only can isolate left ventricular swelling tumor, reduce residual leakage after operation, but also can assist ventricular contraction, realizes mechanical compensation of heart pump failure, and has better practical significance.
In the foregoing embodiments, the descriptions of the embodiments are focused on, and the parts of a certain embodiment that are not described or depicted in detail may be referred to in the related descriptions of other embodiments.
It should be noted that the above embodiments can be freely combined as needed. The foregoing is merely a preferred embodiment of the present application and it should be noted that modifications and adaptations to those skilled in the art may be made without departing from the principles of the present application, which are intended to be comprehended within the scope of the present application.