CN115430008B - Catheter sheath group convenient to operation - Google Patents

Abstract

The invention discloses a catheter sheath group convenient to operate, which comprises a sheath tube seat, wherein a catheter is sleeved in the sheath tube seat in a sliding manner, a guide wire is penetrated in the catheter, the distal end of the catheter is a pre-stress section, the pre-stress section is in a vortex state free from external force and a stress state in which the guide wire is penetrated, and the pre-stress section is adapted to the shape of the guide wire in the stress state. According to the catheter sheath group convenient to operate, the catheter enters the coronary artery opening under the action of the guide wire, at the moment, the prestress section at the distal end of the catheter is in a stress state, namely a curve shape suitable for the shape of the guide wire, when the guide wire is withdrawn out of the sheath tube seat, the prestress section at the distal end of the catheter is in a vortex state, and compared with a straight line state, the vortex state can be provided with more output holes in the same contrast region, so that more contrast agent is output, and the selection of a smaller type of catheter is possible.

Description

Catheter sheath group convenient to operation

Technical Field

The invention relates to the technical field of medical equipment, in particular to a catheter sheath group convenient to operate.

Background

Coronary artery disease, i.e. coronary heart disease, is one of the most mortality diseases, and coronary angiography is a main method for solving the coronary heart disease, and the coronary angiography step is performed by using a catheter such as a hairline to travel along the artificial entrance of the radial artery (wrist) or the femoral artery (thigh) to the coronary artery opening of the heart, and then injecting a contrast agent (visualized under X-rays) into the coronary artery, so that the internal form of the coronary artery can be displayed, for example, whether the coronary artery has stenosis, plaque, etc., but the heart form is basically unknown through the examination, and the internal form of the coronary artery and the blood flow velocity in the coronary artery are basically known.

If the authorized bulletin number is CN105498067a, the publication date is 2016, the name is "radial artery coronary angiography catheter and its using method" is 20, the catheter is composed of three sections of first catheter, second catheter and head catheter, the first catheter is straight tube, two 135 degree bends exist at one end of the second catheter connected with the first catheter, one end connected with the head catheter is perpendicular to the first catheter, the head catheter is reverse S shape, and side hole is set on the wall of the head catheter, its characterized in that: the first catheter is of an outer, middle and inner three-layer structure, the inner and outer layers are made of nylon, the middle layer is a metal woven mesh, the second catheter is made of nylon plastic, and the head catheter is made of soft nylon. The head catheter is made of soft nylon, has a soft structure, can reduce the damage of the head end of the catheter to blood vessels in the process of entering the coronary artery and the radiography process, adopts an inverse S-shaped structural design, is easier to enter the right coronary artery, avoids entering the branches of the right coronary artery, and avoids serious complications. The second conduit is made of nylon plastic and has moderate hardness as a connecting transition section of the first conduit and the head conduit. The radial artery coronary angiography catheter using method utilizes the guiding function of the sheath catheter holder and the guide wire on the coronary angiography catheter, and the catheter easily enters the coronary artery, so that the operation difficulty and the operation complications are reduced.

The operation method of the prior art for the angiography operation of the heart mainly comprises the steps of firstly feeding a guide wire into a blood vessel of a human body to the coronary artery opening of the heart through a sheath tube seat, guiding a catheter to the coronary artery opening of the heart through the guide wire, then retracting the guide wire, bending blood vessels in the heart, leading to thinner blood vessel walls, damaging the blood vessel walls in the process that the catheter enters the heart along the guide wire, and obviously, leading to the vascular perforation for serious patients with larger damage possibly caused by the thicker catheter, so that the operation is extremely difficult. So, where possible, finer catheters are better, but on the other hand, catheters are used to deliver contrast agent to the contrast area, which is not large (e.g. hemangiomas), and finer catheters in a limited space are limited to deliver contrast agent, thereby affecting the contrast effect, and on the basis of this, the prior art needs to select the finest catheter in satisfying the need for a limited spatial contrast agent delivery.

Disclosure of Invention

The present invention aims to provide a catheter sheath group which is convenient to operate, and aims to solve the above-mentioned disadvantages in the prior art.

In order to achieve the above object, the present invention provides the following technical solutions:

the utility model provides a catheter sheath group convenient to operation, includes the sheath tube seat, the slip in sheath tube seat has the pipe, wear to be equipped with the seal wire in the pipe, the distal end of pipe is the prestressing force section, the prestressing force section has the vortex state that does not receive external force and wears to be equipped with the stress state of seal wire under the stress state, the prestressing force section adaptation in the appearance of seal wire.

The catheter sheath group convenient to operate is characterized in that the prestress section is provided with a plurality of liquid discharge holes.

The catheter sheath group convenient to operate is provided with the first groove on the inner wall of the sheath tube seat, the first groove is a circular groove adapting to the inner wall of the sheath tube seat, the groove body with one third of circular arc on the circumferential length of the first groove is in a closed shape, the elastic ring is connected with the first groove in a rotating mode, and the rotating amplitude of the elastic ring is enabled to be not more than 240 degrees by the closed groove body.

The above-mentioned catheter sheath group convenient to operation, the elasticity ring include elasticity inner ring and elasticity outer loop, elasticity outer loop elasticity cup joint in on the elasticity inner ring, elasticity inner ring cup joint in the proximal end of pipe, circumference is provided with a plurality of blocks on the elasticity outer loop, be provided with a plurality of second recesses on the block, a plurality of the interval of second recess equals, be provided with protruding annular portion on the elasticity inner ring, protruding annular portion with second recess one-to-one.

In the catheter sheath group convenient to operate, the elastic inner ring is provided with an axial extension part, and the elastic inner ring extends out of the sheath tube seat through the extension part.

In the catheter sheath group convenient to operate, the catheter rotates to drive the elastic inner ring to rotate, and the elastic inner ring drives the elastic outer ring to rotate.

The catheter sheath group convenient to operate is characterized in that the groove wall of the first groove is extruded to be tightly attached to the elastic outer ring, the extension part of the elastic inner ring extending out of the sheath tube seat is rotated, and the elastic inner ring rotates to enable the convex annular part on the elastic inner ring to pass through the second groove on each block body so as to realize the adjustment of the inner diameter of the elastic inner ring.

In the catheter sheath group convenient to operate, four blocks are circumferentially arranged on the elastic outer ring.

In the catheter sheath group convenient to operate, the block body is provided with three second grooves.

In the catheter sheath group convenient to operate, the second groove is an annular groove.

In the above technical solution, according to the catheter sheath group convenient to operate provided by the embodiment of the invention, the catheter enters the coronary artery opening under the action of the guide wire, at this time, the prestress section at the distal end of the catheter is in a stress state, namely in a curve shape suitable for the shape of the guide wire, and when the guide wire is withdrawn from the sheath tube seat, the prestress section at the distal end of the catheter is in a vortex state, and compared with a straight line state, more output holes can be formed in the same contrast area in the vortex state, so that more contrast agent is output, and the selection of a smaller type of catheter becomes possible.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings that are needed in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments described in the present invention, and other drawings may be obtained according to these drawings for a person having ordinary skill in the art.

FIG. 1 is a schematic view of a catheter sheath assembly according to an embodiment of the present invention;

FIG. 2 is a schematic diagram of a structure of a prestress of a catheter sheath set in a stress state, which is convenient to operate and provided by an embodiment of the invention;

FIG. 3 is a schematic illustration of a structure of a prestress of a catheter sheath set in a vortex state for easy operation according to an embodiment of the present invention;

FIG. 4 is a schematic view of a catheter sheath assembly according to another embodiment of the present invention;

FIG. 5 is a partial cross-sectional view of a catheter sheath assembly according to yet another embodiment of the present invention for ease of handling;

FIG. 6 is a schematic view of the structure of the elastic inner ring and the elastic outer ring of the catheter sheath assembly according to yet another embodiment of the present invention;

fig. 7 is a schematic view showing the cooperation of the second groove and the convex ring portion according to still another embodiment of the present invention.

Reference numerals illustrate:

1. a guide wire; 2. a conduit; 3. a sheath holder; 4. a pre-stress section; 5. a first groove; 6. a boss; 7. an elastic ring; 8. an elastic inner ring; 9. an elastic outer ring; 10. a convex annular portion; 11. a block; 12. and a second groove.

Detailed Description

In order to make the technical scheme of the present invention better understood by those skilled in the art, the present invention will be further described in detail with reference to the accompanying drawings.

In various embodiments of the present invention, "proximal" and "distal" are relative orientations, relative positions, directions of elements or actions relative to one another from the perspective of a physician using the medical device, although "proximal" and "distal" are not intended to be limiting, and "proximal" generally refers to the end of the medical device that is proximal to the physician during normal operation, and "distal" generally refers to the end that is distal to the physician that first enters the patient, the forward and reverse rotations indicated by the present invention are not in a plain sense, but are rotation in two opposite directions.

Referring to fig. 1-7, the catheter sheath group provided by the embodiment of the invention comprises a sheath tube seat 3, a catheter 2 is sleeved in the sheath tube seat 3 in a sliding manner, a guide wire 1 is sleeved in the catheter 2 in a sliding manner, the distal end of the catheter 2 is a pre-stress section 4, the pre-stress section 4 has a vortex state free from external force and a stress state in which the guide wire 1 is penetrated, and the pre-stress section 4 is adapted to the shape of the guide wire 1 in the stress state.

Specifically, as shown in fig. 1, the distal end of the sheath tube holder 3 (i.e. the end entering the human body) is used for being placed in an artery, the proximal end of the sheath tube holder 3 is located outside the body, the inside of the sheath tube holder 3 is formed with an axial through hole for the catheter 2 to enter the arterial vessel, the catheter 2 is internally provided with the guide wire 1 in a penetrating manner, the guide wire 1 is then withdrawn from the lesion from the human body vessel under the guidance of the guide wire 1, and then contrast agent is injected into the lesion through the catheter 2, the distal end of the catheter 2 is a pre-stressed section 4, the pre-stressed section 4 refers to that the part is applied with pre-stress during manufacturing so as to enable the part to have elasticity so as to be in a vortex shape, namely an inner roll shape, the catheter 2 in the prior art is in a straight shape or basically straight shape, the embodiment applies pre-stress to be arranged in a vortex shape on the basis of the distal end during manufacturing, but the pre-stress is smaller, or the pre-stress section 4 has a smaller elastic coefficient, when the guide wire 1 is arranged in the catheter 2 in a penetrating manner, and the guide wire 1 is located in the lesion section 4, the pre-stress section 1 is in a state, the pre-stress section 4 is in which the hardness is larger than the guide wire 1 is in a state, and the pre-stress section 4 is in a state, and the pre-stress section is forced to be in a state of being in which the line is in which the pre-stress section 4 is in a state of being in a stress state of being in which the pre-stress is in a stress. In the stress state, the prestress section 4 is adapted to the shape of the guide wire 1, for example, the guide wire 1 is linear, the prestress section 4 is also linear, and in the vortex state, the prestress section 4 is not subjected to external force, and naturally bends into a vortex shape, because the guide wire 1 is inside and the elastic coefficient of the prestress section 4 is smaller than that of the guide wire 1. In this embodiment, the prestressing segment 4 is provided with a plurality of liquid discharge holes, during the operation, the vortex formed by the prestressing segment 4 is arranged to the position for discharging the contrast agent, then the contrast agent is synchronously output from the plurality of liquid discharge holes through the catheter 2, the vortex structure can be provided with more liquid discharge holes in the same area, and more contrast agent meeting the output speed is conveyed in the unit area by increasing the flow rate of the liquid in the catheter; moreover, when the contrast agent is released, the pre-stress section 4 has elasticity, so that the pre-stress section 4 can have a swinging motion under the impact of the contrast agent during the releasing process, and the contrast agent with high concentration can be more uniformly distributed to the contrast area.

According to the catheter sheath group convenient to operate, the catheter enters the coronary artery opening under the action of the guide wire, at the moment, the prestress section at the distal end of the catheter is in a stress state, namely a curve shape suitable for the shape of the guide wire, when the guide wire is withdrawn out of the sheath tube seat, the prestress section at the distal end of the catheter is in a vortex state, and compared with a straight line state, the vortex state can be provided with more output holes in the same contrast area, so that more contrast agent is output, and the selection of a smaller type of catheter is possible.

In one embodiment provided by the present invention, as shown in fig. 3, the prestress section 4 is provided with a plurality of liquid discharge holes (not shown in the figure), the contrast medium can be injected into the lesion of the coronary artery through the liquid discharge holes, in the prior art, for the selection of the catheter during the contrast operation, the catheters of 4F and 5F are commonly used, the advantage of the catheters of the relative 4F catheter 2 and the 5F catheter 2,4F is that the small-caliber catheter 2 has small damage to the blood vessel, especially in the radial artery (wrist), the blood vessel of the radial artery is thinner than other blood vessels in the human body, the diameter of the 4F catheter, namely the small-caliber catheter, can reduce the radial artery spasm and the radial artery vascular damage, the advantage of the 5F catheter is that the caliber is larger but the damage to the blood vessel is larger, the contrast medium injected into the lesion by the 5F catheter 2 in the same lesion and in the same time period is larger than the contrast medium injected into the lesion by the 4F catheter in the contrast region, the catheter 2 with a linear distal end has a limited opening, the contrast medium output by the 4F catheter 2 is obviously less than that output by the 5F catheter 2, and may not be able to achieve a satisfactory contrast effect for some patients, in this embodiment, a plurality of drainage holes are provided in the pre-stress section 4, and contrast medium can be injected into the coronary artery through the drainage holes, at the same lesion, the pre-stress section 4 is provided with a plurality of drainage holes for enabling the distal end of the catheter to have a larger contrast medium inlet relative to the catheter at the linear end, so that the 4F catheter can also provide the same or similar contrast medium amount as the 5F catheter 2, and the contrast medium is instantaneously flushed out of the catheter into the lesion, the pre-stress section 4 can be forced to swing during the flushing of the contrast medium, at this time, the lesion area can be displayed more and the specific condition of the lesion can have a clear response, the advantage of arranging the liquid discharge hole in the prestress section 4 is that the catheter with small caliber can be selected during the radiography operation, and the better radiography effect can be achieved.

In another embodiment provided by the invention, as shown in fig. 4 and 5, a first groove 5 is arranged on the inner wall of the sheath tube seat 3, the first groove 5 is an arc groove adapting to the inner wall of the sheath tube seat 3, namely, the first groove is not a complete annular groove, for example, the circumferential length of the first groove is two thirds of an arc, the corresponding part of the other third of the arc is a closed shape, the sheath tube seat 3 is rotationally connected with an elastic ring 7, the elastic ring 7 is made of elastic material, the elastic ring 7 is also in a circular shape adapting to the shape of the catheter 2, the radial dimension of the elastic ring 7 is arranged to be elastically sleeved on the catheter 2, namely, the radial dimension of the inner wall of the elastic ring 7 is smaller than the radial dimension of the outer wall of the catheter 2, thus, when the catheter 2 is rotated, the elastic ring 7 also rotates in the same direction, a convex part 6 is also arranged on the elastic ring 7, and the convex part 6 is movably connected in the first groove 5, the catheter 2 drives the elastic ring 7 to rotate when rotating, the elastic ring 7 drives the bulge 6 to rotate in the groove when rotating, the bulge 6 on the elastic ring 7 is also driven to rotate in the rotating process of the catheter 2, obviously, when the bulge 6 rotates to the closed end of the first groove 5, the closed end of the first groove 5 can block the bulge 6 to resist the rotating resistance so as not to rotate, doctors know that the catheter 2 is subject to the rotating resistance, at the moment, the doctors can rotate the catheter 2 reversely for a plurality of angles and then forward rotate, so that the catheter 2 can continuously enter or exit the human blood vessel, the closed third arc corresponding to the first groove 5 can limit the rotating range of the elastic ring 7 third, so that the first groove limits the rotating range of the catheter, the operation steps of feeding or withdrawing the catheter into or from the blood vessel of the human body are that the catheter rotates in one direction for a period of time and then rotates in the other direction, the operation steps are summarized in practice of a plurality of doctors, the rotation amplitude cannot exceed 240-270 degrees, otherwise, the catheter 2 is easily broken and damaged, when the doctor repeatedly rotates and feeds or withdraws the catheter 2, the rotation amplitude cannot exceed 240 degrees, in actual operation, each forward rotation is inconsistent with the reverse rotation amplitude, a certain accumulated rotation amplitude is caused after each rotation, the doctor can rotate in the forward rotation or reverse rotation angle by training and working experience, the difference of the rotation angle of the catheter is possibly small, such as the rotation amplitude of the catheter is only 60 degrees after each forward rotation, but the accumulated rotation amplitude of the catheter 2 is possibly exceeding 270 degrees at the operation tail section due to overlong length of the catheter, the sealed section is arranged in the first groove, the bulge part on the elastic ring is enabled to be subjected to rotation resistance when rotating, so that the operator knows that the accumulated rotation amplitude is overlarge, the bulge part on the elastic ring is inverted, any position in the first groove 5 can be obtained at this moment, and the bulge part 6 can be repeatedly rotated in the direction of the first groove 5, so that the rotation angle of the bulge part 7 can be repeatedly fed into or withdrawn from the human body in the direction of the human body.

In a further embodiment, one end of the protruding portion 6 is connected to a microprotrusion at the arc-shaped middle of the groove wall of the first groove 5 through a tearing portion, the tearing portion is of a structure with connection strength smaller than that of the protruding portion 6, for example, a structure with thickness of half or even one third of the protruding portion is easy to tear and break, the elastic ring 7 is directly connected to the middle of the first groove 5 through the protruding portion 6 in an initial state, positioning is facilitated, the elastic ring 7 cannot rotate by itself, then in use, the tearing portion is broken by forcefully rotating the elastic ring 7, the tearing portion connection force is small and easy to break, in use, the tearing portion of the protruding portion 6 has an obvious click feeling when passing through the microprotrusions, and a doctor can be reminded that the doctor is supposed to rotate the middle portion of a rotating stroke, and the probability that the protruding portion 6 rotates to an extreme position is reduced.

In another embodiment provided by the invention, as shown in fig. 6, the elastic ring 7 comprises an elastic inner ring 8 and an elastic outer ring 9, the elastic outer ring 9 is sleeved in the first groove 5, the elastic outer ring 9 is elastically sleeved on the elastic inner ring 8, the elastic inner ring 8 is elastically sleeved on the catheter 2, the distal end of the elastic inner ring 8 extends to the outside of the sheath tube socket 3, a plurality of blocks 11 are circumferentially arranged on the inner wall of the elastic outer ring 9, preferably, four blocks 11 are circumferentially arranged on the elastic outer ring 9, the blocks 11 are in a triangular (circumferentially three-face) structure, one face of each block is attached to the inner wall face of the outer ring, the other face is an inclined face, the other face is a radial face, a plurality of second grooves 12 are arranged on the inclined face of each block 11, each second groove 12 is elastic, preferably, three second grooves 12 are arranged on one block 11, the shapes of the second grooves 12 are annular grooves, the elastic inner ring 8 is provided with a convex annular part 10 made of soft elastic materials, preferably, the convex annular part 10 is annular, the convex annular part 10 corresponds to the second grooves 12 one by one, the convex annular part 10 is limited in the second grooves 12, the convex annular part 10 has obvious click feeling when completely entering the second grooves 12, so that doctors know that the convex annular part 10 passes through the second grooves 12 when rotating the inner ring, the convex annular part 10 on the elastic inner ring 8 rotates and passes through each second groove 12 sequentially when rotating, obviously, when the convex annular part 10 is positioned in different second grooves 12, the radial sizes of channels on the inner side of the elastic inner ring 8 are different, the radial sizes of channels of the catheter 2 on the inner side of the inner ring can be adjusted by adjusting the relative positions of the elastic inner ring 8 and the elastic outer ring 9, the corresponding blood vessel sizes are different in different operation, the inner diameters of the required catheters 2 are different, so that the rotatable inner ring is provided to adjust the inner ring sizes of the catheters 2 with different calibers, when the convex annular part 10 passes through three annular grooves, the inner diameters of the catheters 2 are correspondingly different, correspondingly, the groove walls of the positions of the sheath tube base 3 opposite to the elastic outer ring 9 are made of elastic materials, namely, when a doctor needs to adjust, the doctor presses the groove walls of the elastic materials on the sheath tube base 3 by one hand to tightly fit the elastic outer ring 9 so as to limit the elastic outer ring 9, then the other hand only needs to rotate the extending part of the elastic inner ring 8 extending out of the sheath tube base 31, and the convex annular part 10 on the elastic inner ring 8 rotates to adjust the inner diameters of the catheters 2 with different radial sizes, such as catheters with 3F-5F, when passing through the annular grooves.

Further, as shown in fig. 7, the extending direction of the second groove 12 is the axial position of the catheter and the sheath tube socket 1, the protruding annular portion 10 is configured as a half boss structure, that is, the radial dimension of the protruding annular portion 10 from one end to the other end along the axial direction of the elastic inner ring 8 is gradually smaller, the axial dimension of the half boss structure is more than three times of the axial dimension of the second groove 12, and in the initial position, the half boss structure is inserted into the second groove 12 with the middle portion thereof, so that the portion of the elastic inner ring 8 matched with the second groove 12 is enlarged or reduced by pulling the elastic inner ring 8 axially, so that for each catheter 2, the radial dimension of the elastic inner ring 8 can be finely adjusted by pulling the inner ring axially, that is, the magnitude of the friction force between the elastic inner ring 8 and the catheter can be adjusted, so that a doctor can adjust the drawing resistance of the catheter 2 relative to the elastic inner ring 8 within a certain range.

While certain exemplary embodiments of the present invention have been described above by way of illustration only, it will be apparent to those of ordinary skill in the art that modifications may be made to the described embodiments in various different ways without departing from the spirit and scope of the invention. Accordingly, the drawings and description are to be regarded as illustrative in nature and not as restrictive of the scope of the invention, which is defined by the appended claims.

Claims (9)

1. The catheter sheath group convenient to operate comprises a sheath tube seat, a catheter is sleeved in the sheath tube seat in a sliding manner, a guide wire is penetrated in the catheter, the catheter is characterized in that the distal end of the catheter is a prestress section, the prestress section has a vortex state free from external force and a stress state penetrated by the guide wire, the prestress section is adapted to the shape of the guide wire in the stress state,

the inner wall of the sheath tube seat is provided with a first groove, the first groove is an arc groove which is suitable for the inner wall of the sheath tube seat, the circumferential length of the first groove is two thirds of an arc, the part of the other third of the arc is closed, the sheath tube seat is rotationally connected with an elastic ring, the radial dimension of the elastic ring is set to be capable of being elastically sleeved on a catheter, the elastic ring can also generate the same-direction rotation when the catheter is rotated, the elastic ring is also provided with a protruding part which is movably connected in the first groove, the catheter drives the elastic ring to rotate when rotating, the protruding part is driven to rotate in the first groove when rotating, the protruding part on the elastic ring is also driven to rotate when rotating,

one end of the protruding portion is connected to a microprotrusion at the arc-shaped middle part of the groove wall of the first groove through the tearing portion, the tearing portion is of a structure with connection strength smaller than that of the protruding portion, the elastic ring is directly connected to the middle part of the first groove through the protruding portion in an initial state, the elastic ring cannot rotate automatically, then the tearing portion is broken through the elastic ring by forceful rotation when the elastic ring is used, and in the use process, the tearing portion of each protruding portion has a clamping feeling when passing through the microprotrusions.

2. The easy-to-handle catheter sheath set of claim 1, wherein the pre-stressing section is provided with a plurality of weep holes.

3. The catheter sheath group convenient to operate according to claim 1, wherein the elastic ring comprises an elastic inner ring and an elastic outer ring, the elastic outer ring is elastically sleeved on the elastic inner ring, the elastic inner ring is sleeved on the proximal end of the catheter, a plurality of blocks are circumferentially arranged on the elastic outer ring, a plurality of second grooves are arranged on the blocks, the distances between the plurality of second grooves are equal, and a convex annular part is arranged on the elastic inner ring and corresponds to the second grooves one by one.

4. The steerable catheter sheath assembly of claim 3, wherein the resilient inner ring has an axial extension through which the resilient inner ring extends outside the sheath hub.

5. The steerable catheter sheath assembly of claim 4, wherein the catheter rotation rotates the inner resilient ring, which rotates the outer resilient ring.

6. The steerable catheter sheath assembly of claim 5, wherein the walls of the first groove are compressed to tightly fit the outer resilient ring and the extension of the inner resilient ring beyond the sheath hub is rotated, the inner resilient ring rotating such that the raised annular portion on the inner resilient ring passes through the second groove on each of the blocks to effect adjustment of the inner resilient ring diameter.

7. The easy to handle catheter sheath assembly of claim 6, wherein four blocks are circumferentially disposed on the resilient outer ring.

8. The steerable catheter sheath assembly of claim 7, wherein three second grooves are provided on the block.

9. The easy to handle catheter sheath assembly of claim 8, wherein the second groove is an annular groove.

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