Background
Pulmonary artery embolism (abbreviated as pulmonary embolism pulmonary embolism, PE) is caused by the fact that peripheral deep venous thrombosis or thrombus of a right heart chamber fall off into pulmonary circulation to block pulmonary artery or branches thereof, and a series of clinical pathophysiological changes mainly caused by pulmonary circulation dysfunction are further caused, and sudden death is seriously caused. Studies show that the emboli causing PE to occur mainly originate from thrombus shed by deep veins of limbs or pelvic veins, accounting for 60% -90% of the emboli sources. The deep venous thrombosis is a common disease which is harmful to human health, the incidence rate rises year by year, and an important complication is repeated shedding of the thrombus, so that pulmonary arterial embolism and pulmonary infarction are caused, the mortality rate is extremely high, and the life of a patient is seriously endangered. The traditional operation treatment is adopted, the wound surface is large, the risk is high, the interventional treatment is adopted in recent years, the percutaneous inferior vena cava filter implantation is adopted by a percutaneous puncture method, a metal filter is placed in the inferior vena cava through a sheath conveyer, and the filter can prevent thrombus from ascending and prevent or reduce pulmonary arterial thromboembolism. Percutaneous vena cava filter placement is simple, safe, and effective compared to conventional surgical procedures, and has been widely used in recent years.
Medical sheath tubes are often used in the minimally invasive interventional therapy operation to establish a delivery channel from outside to inside of the vena cava filter. All kinds of sheath pipes for vena cava filter transportation which are put into clinical use at present are linear, when the sheath pipes run in blood vessels, the distal ends of the sheath pipes cannot be positioned in the center of vena cava due to the action force of the blood vessels caused by the natural physiological bending of the blood vessels, and the problem causes that when the filter is released, the filter cannot be accurately released along the long axis of the vena cava, and then the filter is possibly unstable to be fixed, so that complications such as later-stage filter displacement, wall attachment, vein wall puncture and the like occur. If the distal direction of the sheath can be regulated and controlled during the filter delivery process, the sheath can be accurately positioned in the long axis direction of the vena cava after being moved to the target position, the success rate of filter release can be effectively increased, and the complication occurrence rate can be reduced.
Although the bending angle of the distal end of the sheath tube can be adjusted, in the prior art, the distal end of the sheath tube is fixed at a certain point in the prior art, when the distal end of the sheath tube is pulled by a traction wire at the proximal end of the sheath tube, the end part of the sheath tube is often bent first, and then the rear section is slowly driven to perform arc transition bending, so that the filter conveying function cannot be realized. Thus, the prior art does not meet the above-described requirements for parallel placement of filters.
How to solve the problem that the release filter cannot be parallel to the inferior vena cava is a problem which needs to be solved by the person skilled in the art at present.
Disclosure of Invention
The invention aims to provide an adjustable bent sheath tube and a lower vena cava filter conveying device, which can release a filter at the position of the long axis center line of the lower vena cava, thereby improving the safety and effectiveness of filter release.
In order to achieve the above purpose, the present invention mainly provides the following technical solutions:
in one aspect, the invention provides an adjustable bend sheath comprising a sheath body, an adjusting wire and a regulator, wherein,
The sheath tube body is made of flexible materials, and can bend along with the trend of a blood vessel under the action of a guide wire after entering the body;
A channel penetrating along the length direction of the sheath tube body is arranged in a tube wall interlayer of the sheath tube body, the adjusting wire penetrates from the proximal end of the channel, reaches the distal end of the channel and is fixed with a fixing section arranged at the distal end of the sheath tube body, the adjusting wire is fixed with the whole section of the sheath tube body along the length of the fixing section, and the fixing section is in a straight line state in a natural state;
the proximal end of the adjusting wire is connected with an adjusting unit of the adjuster, and the adjusting wire deflects the whole fixed section by an angle under the pulling of the adjusting unit.
Preferably, the number of the adjusting wires is more than two, and the adjusting wires are symmetrically distributed in the pipe wall of the sheath pipe body along the center of the section of the sheath pipe body.
Preferably, the device further comprises a connector, wherein the connector at least comprises three passages which are communicated with each other, a first passage is connected with the sheath tube body, a second passage is connected with the regulator, and the regulating wire enters the second passage from the first passage and is connected with the regulating unit.
Preferably, the first, second and third passages form a Y-or T-shaped structure.
Preferably, the regulator is manually or automatically controlled.
Preferably, the adjuster comprises a self-locking device.
On the other hand, the invention also provides a inferior vena cava filter conveying device which comprises the adjustable bent sheath tube, a filter and a filter releasing unit, wherein the filter releasing unit carries the filter to be conveyed into a body from the lumen of the adjustable bent sheath tube along the direction from the proximal end to the distal end and is released.
Preferably, the filter further comprises a recovery hook disposed at the tail end of the filter.
The beneficial effects are that:
According to the technical scheme, the through channel which is penetrated along the length direction is arranged in the pipe wall interlayer of the sheath pipe body, the regulating wire penetrates through the proximal end of the channel, reaches the distal end of the channel and is fixed with the fixing section which is arranged at the distal end of the sheath pipe body, the regulating wire is fixed with the whole section of the sheath pipe body along the length of the fixing section, and the fixing section is a straight line section which is different from a point, so that when the regulating wire is fixed with the whole fixing section, the fixing section is still in a straight line state in a natural state, and meanwhile, the proximal end of the regulating wire is connected with the regulating unit of the regulator, the regulating wire can enable the whole fixing section to deflect by an angle with other sheath pipe parts which are connected with the regulating wire under the pulling of the regulating unit, and therefore, the sheath pipe body can be in a state parallel to a long vena cava when the filter is released after the junction of left and right iliac veins is bent upwards, and the filter is released, and the filter can be placed in the optimal position when the filter is placed along the releasing direction.
The foregoing description is only an overview of the present invention, and is intended to provide a better understanding of the present invention, as it is embodied in the following description, with reference to the preferred embodiments of the present invention and the accompanying drawings.
Drawings
FIG. 1 is a schematic view showing the overall structure of an adjustable curved sheath according to an embodiment of the present invention;
FIG. 2 is a schematic cross-sectional view of an adjustable curved sheath according to an embodiment of the present invention;
FIG. 3 is a schematic diagram of another implementation of an adjustable bend sheath according to an embodiment of the present invention;
FIG. 4 is a schematic view of the disassembled structure of FIG. 3;
FIG. 5 is a view showing the structure of FIG. 3 with the anchor section tilted under tension;
FIG. 6 is a schematic diagram showing an embodiment of an adjustable bend sheath according to the present invention;
Fig. 7 is a schematic structural view of a inferior vena cava filter delivery device according to another embodiment of the invention.
The reference numerals are as follows:
Sheath tube 10, channel 11, fixed section 12, adjusting wire 20, adjuster 30, adjusting unit 31, guide groove 32, rotary cylinder 33, end cap 34, strut 35, graduation 331, connector 40, first passage 41, second passage 42, third passage 43, filter 1, adjustable bent sheath tube 2, filter releasing unit 3, and recovery hook 4.
Detailed Description
The following examples are illustrative of the invention and are not intended to limit the scope of the invention. The technical means used in the examples are conventional means well known to those skilled in the art unless otherwise indicated.
Example 1
As shown in fig. 1 to 6, one embodiment of the present invention provides an adjustable bend sheath including a sheath body 10, an adjusting wire 20, and a regulator 30. The sheath tube body 10 is made of flexible materials, comprises a hollow tube cavity, and a guide wire passes through the tube cavity to guide the sheath tube body 10 to enter the body, and can bend along the trend of a blood vessel under the action of the guide wire, so that the guide wire can advance along the wall of the blood vessel. The proximal end of the sheath tube body 10 is exposed outside the body and fixedly connected with the regulator 30, so as to facilitate the operation of an operator. Hereinafter, the end farther from the operator is referred to as the distal end, and the end closer to the operator is referred to as the proximal end, based on the position of the operator.
The sheath tube body 10 is characterized in that a channel 11 penetrating along the length direction is arranged in a tube wall interlayer of the sheath tube body 10, the adjusting wire 20 penetrates from the proximal end of the channel 11, reaches the distal end of the channel 11 and is fixed with the fixing section 12 arranged at the distal end of the sheath tube body 10, and the adjusting wire 20 is fixed with the whole fixing section 12, so that the fixing section 12 is in a straight line state in a natural state.
As shown in fig. 4, the proximal end of the adjusting wire 20 is connected to the adjusting unit 31 of the adjuster 30, and the adjusting wire 20 deflects the whole of the fixing segment 12 by an angle (as shown in fig. 5) by pulling the adjusting unit 31. When the tension of the adjusting wire 20 is released, the sheath tube 10 can be restored to a natural state under the elastic action of itself.
According to the technical scheme, the through channel which is penetrated along the length direction is arranged in the pipe wall interlayer of the sheath pipe body, the regulating wire penetrates through the proximal end of the channel, reaches the distal end of the channel and is fixed with the fixing section which is arranged at the distal end of the sheath pipe body, the regulating wire is fixed with the whole section of the sheath pipe body along the length of the fixing section, and the fixing section is a straight line section which is different from a point, so that when the regulating wire is fixed with the whole fixing section, the fixing section is still in a straight line state in a natural state, and meanwhile, the proximal end of the regulating wire is connected with the regulating unit of the regulator, the regulating wire can enable the whole fixing section to deflect by an angle with other sheath pipe parts which are connected with the regulating wire under the pulling of the regulating unit, and therefore, the sheath pipe body can be in a state parallel to a long vena cava when the filter is released after the junction of left and right iliac veins is bent upwards, and the filter is released, and the filter can be placed in the optimal position when the filter is placed along the releasing direction.
In a preferred embodiment, for convenience of operation, the number of the adjusting wires 20 may be more than two, and the more than two adjusting wires 20 are symmetrically distributed in the wall of the sheath tube body 10 along the center of the cross section of the sheath tube body 10. The cross-sectional profile of two wires 20 is shown in fig. 2.
In a preferred embodiment, as shown in fig. 3, 4 and 5, a connector 40 may be further included, where the connector 40 includes at least three passages and communicates with each other. As shown in fig. 4, the first passage 41 is connected to the sheath tube body 10, the second passage 42 is connected to the regulator 30, and the regulator wire 20 enters the second passage 42 from the first passage 41 and is connected to the regulator unit 31. As shown in fig. 3, 4 and 5, the connector 40 includes three passages. Wherein the third passageway 43 may be used to deliver or retrieve a device, introduce a drug or withdraw a body fluid, etc.
One specific implementation of the regulator 30 is that, as shown in fig. 3,4 and 5, the regulator 30 includes a rotating cylinder 33, a support post 35, a guide groove 32, and an end cover 34. Manipulation of the knob 33 may drive the adjustment wire 20 and change the inclination of the fixed segment 12, as shown in fig. 5.
The second passage 42 of the connector 40 is axially connected to the post 35, and a guide groove 32 is disposed along the axis of the post 35, preferably the length of the guide groove 32 is 30% -90% of the length of the post 35, and the guide groove 32 may penetrate through two opposite sides of the post 35 to form a long and narrow frame shape. The adjusting unit 31 shown in fig. 3-5 is a lock slide, which is placed in the guide groove 32 and can translate along the guide groove 32. The rotary cylinder 33 is sleeved on the guide groove 32, and the rotary cylinder 33 is connected with the lock control sliding block through threads. The rotary cylinder 33 can be freely rotated around the support post 35 and closes the guide groove 32. An end cap 34 is secured to the end of the post 35 to prevent the spin basket 33 from being removed from the post 35, but not to prevent free rotation of the spin basket 33. One end of the adjusting wire 20 arranged in the sheath tube body 10 penetrates out of the side wall of the sheath tube body 10 and then is connected with the lock control sliding block. The lock slide is mounted in the guide slot 32, and the lock slide surface has teeth. The inner wall of the rotary cylinder 33 is provided with a spiral tooth slot matched with the tooth of the lock control sliding block, the lock control sliding block is driven by the rotary cylinder 33 to do linear reciprocating motion, and the adjusting wire 20 connected with the lock control sliding block is pulled to enable the whole fixed section 12 of the sheath tube body 10 to incline.
Graduations 331 (e.g., dots, lines, or other symbols) may be formed on the side surface of barrel 33 to indicate the position of the lock slide within guide 32. In order to allow the graduations 331 to be viewed from different directions, each graduation 331 is preferably circumferentially disposed on the side surface of the barrel 33.
Preferably, when the scale 331 corresponds to the pitch of the tooth slot of the rotary cylinder 22, the lock control slider moves one scale, and the rotary cylinder 33 just rotates one turn, so that the operation is more convenient. Alternatively, the distance traveled by the lock slide may be more accurately observed when the pitch is an integer multiple of the pitch of the scale 331.
In a preferred embodiment, the first, second and third passages 41, 42 and 43 may form a Y-type or T-type structure, but are not limited thereto.
In a preferred embodiment, the regulator 30 may be manually or automatically controlled. Fig. 1 shows a manual dial control mode, and fig. 3 to 5 show a manual rotary control mode of the rotary drum 33. It is also possible to design the control automatically, for example by means of a switch, to cause the adjusting unit 31 to pull the adjusting wire 20 to the desired state.
In a preferred embodiment, the regulator 30 may include a self-locking device. For example, in the structures shown in fig. 3 and 4, according to the known inclined plane friction statics analysis, for the maximum static friction coefficient μ between teeth and tooth grooves, as long as the inner diameter D of the rotary cylinder 33 and the pitch D of the tooth grooves satisfy the physical relationship D < pi μ D, the tension in the adjusting wire 20 will keep the static friction state between teeth and tooth grooves, and at this time, the rotary cylinder 33 and the lock slide are in static balance, which is a self-locking state. When the fixed section 12 of the sheath tube body 10 is inclined to a required state, an operator can directly loosen the rotary cylinder 33, the inclination angle of the fixed section 12 is kept unchanged, and the self-locking function can be realized without other auxiliary actions, so that the doctor can conveniently operate other matched instruments simultaneously. When the external force rotates the rotary cylinder 33, the static friction balance between the teeth and the tooth grooves is broken, and the inclination angle of the fixed section 12 of the pipe body can be changed. The rotating cylinder 33 which is not subjected to external force has a self-locking function at any position, and the rotating cylinder 33 can release self-locking at any time, so that great convenience is brought to operation. In practice, the self-locking means may be designed according to the specific form of the regulator 30 being designed.
Example 2
As shown in fig. 7, another embodiment of the present invention provides a inferior vena cava filter delivery device comprising the above-mentioned adjustable curved sheath 2, a filter 1 and a filter release unit 3, wherein the filter release unit 3 carries the filter 2 from the lumen of the adjustable curved sheath 1 into the body in a proximal-to-distal direction and releases it.
The adjustable bent sheath tube comprises a sheath tube body, an adjusting wire and an adjuster, wherein,
The sheath tube body is made of flexible materials, and can bend along with the trend of a blood vessel under the action of a guide wire after entering the body;
A channel penetrating along the length direction of the sheath tube body is arranged in a tube wall interlayer of the sheath tube body, the adjusting wire penetrates from the proximal end of the channel, reaches the distal end of the channel and is fixed with a fixing section arranged at the distal end of the sheath tube body, the adjusting wire is fixed with the whole section of the sheath tube body along the length of the fixing section, and the fixing section is in a straight line state in a natural state;
the proximal end of the adjusting wire is connected with an adjusting unit of the adjuster, and the adjusting wire deflects the whole fixed section by an angle under the pulling of the adjusting unit.
In a preferred embodiment, the filter 1 may further comprise a recovery hook 4, the recovery hook 4 being arranged at the tail end of the filter 1. The trailing end of the filter 1 faces in the distal direction. After the filter 1 is placed in the body for a certain period of time, the filter can be recovered by the recovery hook 4. The recovery hook 4 may be annular as shown in fig. 7, or may be hook-shaped.
According to the technical scheme, the through channel which is penetrated along the length direction is arranged in the pipe wall interlayer of the sheath pipe body, the regulating wire penetrates through the proximal end of the channel, reaches the distal end of the channel and is fixed with the fixing section which is arranged at the distal end of the sheath pipe body, the regulating wire is fixed with the whole section of the sheath pipe body along the length of the fixing section, and the fixing section is a straight line section which is different from a point, so that when the regulating wire is fixed with the whole fixing section, the fixing section is still in a straight line state in a natural state, and meanwhile, the proximal end of the regulating wire is connected with the regulating unit of the regulator, the regulating wire can enable the whole fixing section to deflect by an angle with other sheath pipe parts which are connected with the regulating wire under the pulling of the regulating unit, and therefore, the sheath pipe body can be in a state parallel to a long vena cava when the filter is released after the junction of left and right iliac veins is bent upwards, and the filter is released, and the filter can be placed in the optimal position when the filter is placed along the releasing direction.
While the invention has been described in detail in the foregoing general description and with reference to specific embodiments thereof, it will be apparent to one skilled in the art that modifications and improvements can be made thereto. Accordingly, such modifications or improvements may be made without departing from the spirit of the invention and are intended to be within the scope of the invention as claimed.