Pulmonary artery guide sheath and release and recovery method thereof

Abstract

The pulmonary artery guiding sheath comprises an inner tube and an outer tube, the inner tube is movably arranged in the outer tube in a penetrating mode, an elastic supporting structure is arranged at the front end of the inner tube, and the inner tube and the outer tube can move relatively to drive the elastic supporting structure to be switched between a storage state and a release state relative to the outer tube; when the elastic supporting structure is in the storage state, the elastic supporting structure is stored in the tube cavity of the outer tube; when the elastic supporting structure is in the release state, the elastic supporting structure expands outwards in the radial direction and is matched with the blood vessel wall in a supporting and positioning mode, and the elastic supporting structure in the release state is provided with a gap for blood circulation. The guide sheath has the advantages that the guide sheath has the anti-falling risk, the operation time is saved, the guide sheath is always located in the middle position relative to the pulmonary artery blood vessel so that smooth penetrating and withdrawing of the interventional instrument can be guaranteed, and the situation that the blood vessel wall is broken and damaged in the penetrating and withdrawing process of the interventional instrument is greatly reduced.

Description

Technical Field

[0001] The invention relates to the technical field of pulmonary artery treatment instruments, and in particular to a pulmonary artery guide sheath and a method for releasing and recovering the guide sheath. Background Art

[0002] Pulmonary embolism (PE) refers to a pathophysiological syndrome of pulmonary circulation disorder caused by endogenous or exogenous emboli blocking the pulmonary artery. It is a dangerous and severe clinical disease. The mortality rate of untreated pulmonary embolism is 20-30% (the 30-day mortality rate of high-risk pulmonary embolism patients is 22%; 7.7% for medium- and high-risk patients; 6.0% for medium- and low-risk patients). It is the top three causes of death among cardiovascular diseases. In recent years, my country has attached great importance to the prevention of pulmonary embolism. All major hospitals have built a venous thromboembolism (VTE) prevention and control system to prevent the occurrence of pulmonary embolism. However, there is still a lack of effective treatment for large-area pulmonary embolism that has already occurred.

[0003] There are more than 10 million cases of pulmonary embolism worldwide each year (50-200 / 100,000 people). Conventional anticoagulation and drug thrombolysis are the basic treatments for pulmonary embolism, which can control the progression of symptoms in patients with mild to moderate PE. However, thrombolysis cannot provide rapid and effective treatment for patients with large-area PE, and the risk of bleeding is high. Even if the patient survives, residual thrombus may lead to sequelae such as pulmonary hypertension (CTEPH), which seriously endangers the patient's health. More effective solutions specifically for acute large-area pulmonary embolism are urgently needed in the clinic to make up for this indispensable link in the prevention and treatment of VTE.

[0004] Pulmonary artery thrombectomy usually refers to pulmonary artery thrombectomy, which is a treatment method for acute pulmonary embolism. This surgery can be performed through a variety of routes, such as the inferior vena cava, right atrium, right ventricle, pulmonary artery, aorta and other parts, to remove the thrombus from the pulmonary artery or other parts, thereby restoring blood flow; at this stage, percutaneous catheter intervention can be used to remove the thrombus of acute pulmonary embolism. The intervention method includes hydraulic catheter device for thrombus rheolysis, suction catheter for thrombus aspiration and thrombus rotation, pigtail catheter or balloon catheter for thrombus fragmentation, etc., and the thrombectomy stent can also be used for mechanical thrombectomy of acute ischemic stroke. The guide sheath of the pulmonary artery can effectively help vascular intervention devices such as suction catheters and thrombectomy stents to establish vascular access to reach the lesion site, thereby performing interventional treatment of acute pulmonary embolism.

[0005] However, all the above-mentioned vascular interventional devices for surgical treatment require the introduction of a guide sheath or guide catheter into the lesion site in advance. The pulmonary artery guide sheath, as a type of peripheral vascular guide sheath, is usually used for pulmonary artery interventional surgery. Currently, a universal peripheral guide sheath is used clinically, and there is no guide sheath suitable for the shape of the pulmonary artery. In addition, the guide sheath or guide catheter in the prior art has the following disadvantages when performing interventional surgery:

[0006] 1. Clinically, it is impossible to use a pre-set guide sheath. In addition, the guide sheath does not have a suitable support point in the pulmonary artery. It is very easy for the guide sheath to fall off during surgery, resulting in suspension of the surgery. The interventional device needs to be removed and the guide sheath needs to be reinserted, which greatly prolongs the operation time. This may cause the golden time for emergency treatment to be missed, leading to syncope or even sudden death in patients. The mortality rate of acute pulmonary embolism is as high as 40% when there are syncope symptoms.

[0007] 2. When the interventional device enters, it will generate an outward reaction force on the guide sheath or guide catheter. Combined with the impact of blood flow, it is very easy to cause the guide sheath or guide catheter to slip out of the diseased blood vessel cavity or even fall out of the main blood vessel. This is also the most common adverse event of guide sheath and guide catheter vascular access in clinical practice.

[0008] 3. The current peripheral guide sheath relies on a predetermined catheter shape to ensure that the guide sheath has a support point on the back side of the blood vessel: that is, when the interventional device is inserted into the guide sheath, the guide sheath can rely on the blood vessel support point to resist the outward thrust. However, in emergency surgery for acute pulmonary embolism, since the back side of the pulmonary artery is the right ventricle of the heart, after the guide sheath is inserted and the interventional device is introduced, the guide sheath is subjected to the backward reaction force and blood flow impulse, which will cause the right ventricular wall to be subjected to the predetermined guide sheath pressure, which is likely to cause ventricular damage, palpitations, atrial fibrillation, heartbeat disorder and other serious clinical side effects.

[0009] 4. Clinically, if the tip of the guide sheath is kept in the center of the blood vessel, it is conducive to the penetration of the instrument and reduces the contact between the instrument and the blood vessel wall, reducing the damage to the blood vessel wall and the occurrence of vascular dissection. In actual use, due to the effect of gravity, the tip of the guide sheath is usually close to the blood vessel wall, which greatly increases the contact probability between the interventional instrument and the blood vessel wall, which may cause the instrument to damage the blood vessel wall, leading to blood vessel wall damage and vascular dissection, and causing serious complications. Summary of the invention

[0010] The purpose of the present invention is to provide a pulmonary artery guide sheath and a method for releasing and recovering the guide sheath, which has the effects of preventing the guide sheath from falling off, saving operation time, and keeping the guide sheath in a central position relative to the pulmonary artery blood vessel, thereby ensuring smooth penetration and retrieval of interventional instruments, and greatly reducing the occurrence of rupture and damage to the blood vessel wall during the penetration and retrieval process of the interventional instrument.

[0011] The above technical objectives of the present invention are achieved through the following technical solutions: A pulmonary artery guide sheath comprises an inner tube and an outer tube, wherein the inner tube is movably arranged inside the outer tube, an elastic support structure is arranged at the front end of the inner tube, and the inner tube and the outer tube can move relative to each other, driving the elastic support structure to switch between a storage state and a release state relative to the outer tube;

[0012] When the elastic support structure is in the stored state, the elastic support structure is stored in the lumen of the outer tube;

[0013] When the elastic support structure is in a released state, the elastic support structure is radially expanded outward and cooperates with the blood vessel wall support positioning, and the elastic support structure in the released state is provided with a gap for blood circulation.

[0014] By adopting the above technical solution, in the initial state, the inner tube and the elastic support structure are wrapped in the lumen of the outer tube, and the elastic support structure is in the storage state at this time. The guide sheath with the elastic support structure in the storage state is extended into the pulmonary artery and reaches the expected surgical focus position near the disease, and then the outer tube is pulled back to the outside of the human body by a predetermined length relative to the inner tube, so that the elastic support structure at the end of the inner tube extends from the front end of the outer tube. At this time, the elastic support structure uses its own elastic expansion force to expand radially outward, so that the outer wall of the elastic support structure can be elastically supported with the inner wall of the pulmonary artery to achieve positioning. When the elastic support structure is positioned with the pulmonary artery, the gap of the elastic support structure in the released state is used to achieve continuous blood circulation, so that the release of the elastic support structure is achieved, and then the interventional surgery is performed using the guide sheath in the positioning state with the inner wall of the pulmonary artery; when the guide sheath is recovered, the outer tube is first pushed relative to the inner tube toward the human body by a predetermined length, driving the elastic support structure to undergo elastic deformation and be compressed and stored in the lumen of the outer tube, so as to achieve the storage of the elastic support structure, and finally the guide sheath is withdrawn from the human body as a whole. The present invention utilizes the radial expansion force of the elastic support structure itself in a released state and the elastic support between the inner wall of the blood vessel to achieve support positioning between the end of the guide sheath and the inner wall of the blood vessel, which can effectively prevent the guide sheath from being displaced or detached from the blood vessel due to the pulling or pushing force along the blood vessel direction during the operation using the guide sheath, thereby ensuring the smooth progress of the pulmonary artery intervention operation; and the elastic support structure always maintains a high degree of concentricity with the inner tube and the outer tube, so that the guide sheath is always in the center of the blood vessel during the interventional treatment, which is conducive to the penetration of the interventional instrument, and at the same time greatly reduces the possibility of contact between the interventional instrument and the blood vessel wall, which can greatly reduce the situation of rupture and damage of the blood vessel wall during the process of the interventional instrument penetrating into the pulmonary artery or being withdrawn from the pulmonary artery through the guide sheath, and has the effects of preventing the guide sheath from falling off, saving operation time, and the guide sheath is always in the center position relative to the pulmonary artery, thereby ensuring the smooth penetration and withdrawal of the interventional instrument, and greatly reducing the situation of rupture and damage of the blood vessel wall during the penetration and withdrawal of the interventional instrument.

[0015] The present invention is further configured as follows: the elastic support structure includes a self-expanding stent with radial expansion force, the outer tube has a radial restraining force, and when the elastic support structure is in a stored state, the outer tube relies on the radial restraining force to wrap the inner tube and the self-expanding stent therein.

[0016] By adopting the above technical solution, in the initial state, the elastic support structure is compressed inside the outer tube. When the elastic support structure extends from the end of the outer tube, the self-expanding stent can automatically release and expand outward by relying on its own high expansion coefficient and be tightly positioned against the inner wall of the pulmonary artery. In addition, when the elastic support structure is stored after the interventional surgery is completed, in the process of pushing the outer tube toward the human body relative to the inner tube, the radial restraint force of the outer tube can be used to squeeze and shrink the self-expanding stent radially inward, so that the elastic support structure can be stored in the lumen of the outer tube to reduce the overall volume of the elastic support structure, thereby facilitating the removal of the guide sheath from the human body.

[0017] The present invention is further configured as follows: the self-expanding stent is configured as a spring helical tube having radial elasticity and stretchability and is made by spirally winding a metal wire.

[0018] By adopting the above technical solution, when the spring spiral tube extends out of the outer tube, the radial expansion force of the spring spiral tube can be used to automatically expand the self-expanding stent outward, so that the outer wall of the spring spiral tube and the inner wall of the pulmonary artery are supported and positioned to prevent the guide sheath from slipping relative to the pulmonary artery; in addition, the pitch of the spring spiral tube in the released state forms a gap for blood circulation, which can ensure the circulation of blood in the pulmonary artery.

[0019] The present invention is further configured as follows: the spring spiral tube includes a connecting spiral portion and a supporting spiral portion that are integrally coiled, one end of the connecting spiral portion is fixedly connected to the end of the inner tube, the diameters of the supporting spiral portions are equal, and the diameter of the connecting spiral portion gradually decreases from one end close to the supporting spiral portion toward one end away from the supporting spiral portion.

[0020] By adopting the above technical solution, relying on the setting of the connecting spiral part with a gradually decreasing diameter, the process of retracting the connecting spiral part into the outer tube cavity is smoother. In addition, the supporting spiral part with the same diameter can also be against the inner wall of the pulmonary artery after being unfolded, thereby ensuring the firm positioning between the spring spiral tube and the pulmonary artery after being released.

[0021] The present invention is further configured as follows: the diameter of the metal wire is set between 0.1-2 mm, and the number of turns of the metal wire of the spring spiral tube is set between 2-20 turns.

[0022] The present invention is further configured as follows: the self-expanding stent comprises a plurality of layers of braided mesh tubes braided by braided wires.

[0023] By adopting the above technical solution, the side wall of the braided mesh tube after expansion can be abutted against the inner wall of the pulmonary artery blood vessel to achieve positioning, and the mesh holes of the braided mesh tube after expansion can allow blood to flow in the blood vessel.

[0024] The present invention is further configured as follows: the braided mesh tube comprises at least one radial expansion portion, and when the elastic support structure is in a released state, the radial expansion portion automatically expands outward into a disc shape.

[0025] By adopting the above technical solution, the radially expanded portion that is in a disc shape after expansion can abut against the inner wall of the pulmonary artery to achieve positioning.

[0026] The present invention is further configured as follows: the braided wire of the braided mesh tube is woven from polymer materials, the number of braided strands of the braided mesh tube is set between 2-128, and the braiding density of the braided mesh tube is set between 10-1000PPI.

[0027] The present invention is further configured as follows: the braided mesh tube includes a braided support portion and a braided connection portion that are integrally woven, one end of the braided connection portion is fixedly connected to the end of the inner tube, the diameters of the braided support portions are equal, and the diameter of the braided connection portion gradually decreases from one end close to the braided support portion toward one end away from the braided support portion.

[0028] By adopting the above technical solution, the braided connection part with a gradually smaller diameter makes the process of retracting the braided connection part into the outer tube lumen smoother. In addition, the braided support part with the same diameter can also be against the inner wall of the pulmonary artery after unfolding, ensuring the firm positioning between the braided mesh tube and the pulmonary artery after release.

[0029] The present invention is further configured as follows: the braided wire of the braided mesh tube is made of a plurality of metal wires, the metal wire material is any one of elastic medical metal materials such as nickel-titanium alloy and platinum-tungsten alloy, and the number of metal wire strands of each braided wire is set between 2-128, and the diameter of the metal wire is set between 0.01-10 mm.

[0030] The present invention is further configured as follows: the elastic support structure further comprises a layer of coating film with elastic stretching force wrapped outside the braided mesh tube.

[0031] By adopting the above technical solution, the setting of the covering film can prevent the braided wire of the braided mesh tube from squeezing and scratching the inner wall of the pulmonary artery. In addition, due to the existence of the mesh holes of the braided mesh tube, a gap exists between the covering film at the mesh position and the inner wall of the pulmonary artery, and the gap allows blood to pass through.

[0032] The present invention is further configured as follows: the coating film is made of one or more materials selected from polytetrafluoroethylene, dacron, polyester, and polyurethane, and the thickness of the coating film is set between 0.1-2 mm.

[0033] By adopting the above technical solution, the coating film prepared by using polytetrafluoroethylene, polyester, polyester, and polyurethane can play a good lubricating and protective role on the inner wall of the blood vessel.

[0034] The present invention is further configured as follows: one end of the elastic support structure is connected to the end of the inner tube by welding or a fastener.

[0035] By adopting the above technical solution, the elastic support structure and the end of the inner tube can be firmly connected together by welding or physical fixing with fasteners, which can effectively avoid the separation between the elastic support structure and the inner tube during use.

[0036] The present invention is further configured as follows: a locking structure is provided between the outer tube and the inner tube, and the locking structure can control the inner tube and the outer tube to switch between a locked state and an unlocked state.

[0037] By adopting the above technical solution, when the elastic support structure is in a stored state or a released state relative to the outer tube, the inner tube and the outer tube can be locked and fixed by using a locking structure, so that the inner tube and the outer tube remain fixed and prevent the inner tube and the outer tube from sliding against each other.

[0038] The present invention is further configured as follows: the locking structure includes a positioning seat, a screw sleeve, an annular pressure block and a hose, the positioning seat is provided with a channel extending therethrough in the axial direction, one end of the outer tube is fixedly connected to the positioning seat so that the lumen of the outer tube is connected to the channel, the hose sleeve is arranged outside the outer tube, the positioning seat is threadedly connected to the screw sleeve, the screw sleeve is provided with a pressing portion, the annular pressure block and the hose are coaxially inserted into the channel, the pressing portion is pressed and matched with the annular pressure block, and drives the hose to undergo elastic deformation radially inward.

[0039] By adopting the above technical scheme, the pressing part is moved closer to or away from the annular pressing block by rotating the screw sleeve relative to the positioning seat. When the pressing part presses the annular pressing block, the annular pressing block will press the hose downward. At this time, since the hose is restricted by the inner wall of the channel of the positioning seat on all sides, the hose can only be elastically deformed inward after being squeezed, thereby pressing the outer tube and locking it with the inner tube. When the pressing part is away from the annular pressing block, the pressing force of the annular pressing block on the hose disappears, and the hose resets upward by its own elastic restoring force, so that the channel is conductive. In this way, the locking between the outer tube and the inner tube is achieved by rotating the screw sleeve and using the annular pressing block to press the hose inward to deform it.

[0040] The present invention is further configured as follows: a control base is provided at one end of the inner tube away from the elastic support structure, and the control base is provided with a hemostatic valve connected to the end of the inner tube.

[0041] By adopting the above technical solution, the control base makes it convenient for operators to rotate, push or pull the inner tube, and the addition of the hemostatic valve can prevent blood from flowing out of the body through the lumen of the inner tube.

[0042] The present invention is further configured as follows: the control base is provided with a limit buckle.

[0043] By adopting the above technical solution, the limit buckle can limit the distance that the outer tube moves forward and backward relative to the inner tube, thereby preventing surgical hazards caused by excessive relative sliding between the outer tube and the inner tube.

[0044] Another technical purpose of the present invention is to provide a method for releasing and recovering a pulmonary artery guide sheath, comprising the following steps:

[0045] S1: In the initial state, the inner tube and the elastic support structure are wrapped in the lumen of the outer tube, and the elastic support structure is in a retracted state;

[0046] S2: Extend the introducer sheath with the elastic support structure in the retracted state into the pulmonary artery and reach the expected surgical focus near the lesion;

[0047] S3: Pull the outer tube back to a predetermined length relative to the inner tube toward the outside of the human body, so that the elastic support structure at the end of the inner tube extends out from the front end of the outer tube. At this time, the elastic support structure uses its own elastic expansion force to expand radially outward, so that the outer wall of the elastic support structure can be positioned with the inner wall elastic support of the pulmonary artery;

[0048] S4: When the elastic support structure is positioned and matched with the pulmonary artery, the gap of the elastic support structure in the released state is used to achieve continuous blood circulation;

[0049] S5: Interventional surgery is performed using an introducer sheath that is positioned with the inner wall of the pulmonary artery.

[0050] S6: pushing the outer tube relative to the inner tube toward the human body by a predetermined length, driving the elastic support structure to undergo elastic deformation and be compressed and stored in the lumen of the outer tube, thereby achieving storage of the elastic support structure;

[0051] S7: Withdraw the introducer sheath.

[0052] In summary, the present invention has the following beneficial effects:

[0053] The inner tube is movably inserted into the lumen of the outer tube, and a self-expanding stent is welded to the front end of the inner tube. The self-expanding stent can be switched between being stored in the lumen of the outer tube and being in a stored state or extending out of the outer tube and automatically expanding radially to a released state. In addition, one end of the outer tube is fixedly connected to a positioning seat, and the positioning seat is provided with a channel connected to the lumen of the outer tube. An annular pressure block and a hose are arranged in the channel, and a screw sleeve is threadedly connected to the positioning seat. By rotating the screw sleeve, the pressing part of the screw sleeve is moved close to or away from the annular pressure block. When the pressing part presses the annular pressure block, the annular pressure block presses the hose downward. At this time, since the hose is restricted by the inner wall of the channel of the positioning seat, As a result, the rubber tube can only undergo elastic deformation inward after being squeezed, thereby pressing the outer tube and locking it with the inner tube. When the elastic support structure is positioned with the pulmonary artery, the gap in the elastic support structure in the released state is used to achieve continuous blood circulation, thereby achieving the release of the elastic support structure, and then the interventional surgery is performed using the guide sheath that is in a positioned state with the inner wall of the pulmonary artery. When the guide sheath is recovered, the outer tube is first pushed relative to the inner tube toward the human body by a predetermined length, driving the elastic support structure to undergo elastic deformation and be compressed and stored in the lumen of the outer tube, thereby achieving the storage of the elastic support structure, and finally the guide sheath is withdrawn from the human body as a whole. The present invention utilizes the radial expansion force of the elastic support structure itself in the released state to provide elastic support between the inner wall of the blood vessel, thereby achieving support positioning between the end of the guide sheath and the inner wall of the blood vessel, which can effectively prevent the guide sheath from being displaced or detached from the blood vessel due to the pulling or pushing force along the length direction of the blood vessel during the operation using the guide sheath, thereby ensuring the smooth progress of the pulmonary artery intervention operation; and the elastic support structure always maintains a high degree of concentricity with the inner tube and the outer tube, so that the guide sheath is always in the center of the blood vessel during the interventional treatment, which is conducive to the penetration of the interventional instrument, and at the same time greatly reduces the possibility of contact between the interventional instrument and the blood vessel wall, which can greatly reduce the situation of rupture and damage of the blood vessel wall during the process of the interventional instrument penetrating into the pulmonary artery or being withdrawn from the pulmonary artery through the guide sheath, and has the effects of preventing the guide sheath from falling off, saving operation time, and the guide sheath is always in the center position relative to the pulmonary artery, thereby ensuring the smooth penetration and withdrawal of the interventional instrument, and greatly reducing the situation of rupture and damage of the blood vessel wall during the penetration and withdrawal of the interventional instrument. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] Figure 1 It is a structural diagram of the present invention.

[0055] Figure 2 It is a view showing the inner tube and the outer tube of the present invention separated from each other.

[0056] Figure 3 It is a structural diagram of the elastic support structure in the first specific embodiment of the present invention.

[0057] Figure 4It is a structural diagram of the elastic support structure in the second specific embodiment of the present invention.

[0058] Figure 5 It is a structural diagram of the elastic support structure in the third specific embodiment of the present invention.

[0059] Figure 6 It is a structural diagram of the braided mesh tube of the present invention when it is accommodated in the lumen of the outer tube.

[0060] Figure 7 The present invention Figure 6 A partial enlarged view of area A.

[0061] Figure 8 It is a structural diagram of the elastic support structure in the fourth specific embodiment of the present invention.

[0062] Fig. 9 It is a cross-sectional view of the positioning seat with the outer tube installed and the screw cap separated from each other.

[0063] Fig.10 It is an exploded view of the locking structure of the present invention.

[0064] Fig.11 It is a cross-sectional view of the control base of the present invention.

[0065] In the figure: 1. inner tube; 2. outer tube; 3. self-expanding stent; 31. spring spiral tube; 311. connecting spiral part; 312. supporting spiral part; 32. braided mesh tube; 320. radial expansion part; 321. braided support part; 322. braided connecting part; 4. covering film; 5. positioning seat; 5a. channel; 6. screw sleeve; 61. pressing part; 7. annular pressure block; 8. hose; 9. control base; 91. hemostatic valve; 92. limit buckle. DETAILED DESCRIPTION

[0066] The present invention will be further described below in conjunction with the accompanying drawings. Specific embodiment 1

[0068] A pulmonary artery introducer sheath, such as Figure 1-3As shown, it includes an inner tube 1 and an outer tube 2, the inner tube 1 is movably arranged in the outer tube 2, and an elastic support structure is provided at the front end of the inner tube 1. The inner tube 1 and the outer tube 2 can move relative to each other, driving the elastic support structure to switch between a storage state and a release state relative to the outer tube 2; when the elastic support structure is in the storage state, the elastic support structure is stored in the lumen of the outer tube 2; when the elastic support structure is in the release state, the elastic support structure is radially expanded outward and cooperates with the blood vessel wall support positioning, and the elastic support structure in the release state is provided with a gap for blood circulation; the elastic support structure includes a self-expanding stent 3 with radial expansion force, and the outer tube 2 has a radial restraining force. When the elastic support structure is in the storage state When the outer tube 2 is inserted into the human body, the outer tube 2 wraps the inner tube 1 and the self-expanding stent 3 therein by means of the radial restraint force. In the initial state, the elastic support structure is compressed inside the outer tube 2. When the elastic support structure extends out from the end of the outer tube 2, the self-expanding stent 3 can automatically release and expand outward by means of its own high expansion coefficient and be tightly positioned against the inner wall of the pulmonary artery. In addition, when the elastic support structure is stored after the interventional surgery is completed, in the process of pushing the outer tube 2 toward the human body relative to the inner tube 1, the radial restraint force of the outer tube 2 can be used to squeeze and shrink the self-expanding stent 3 radially inward, so that the elastic support structure can be stored in the lumen of the outer tube 2 to reduce the overall volume of the elastic support structure, thereby facilitating the removal of the guide sheath from the human body.

[0069] like Figure 1-2 and Fig.11 As shown, one end of the elastic support structure is connected to the end of the inner tube 1 by welding or fasteners. The elastic support structure and the end of the inner tube 1 can be firmly connected by welding or fasteners. The elastic support structure and the end of the inner tube 1 can be effectively prevented from being separated from each other during use. A control base 9 is provided at the end of the inner tube 1 away from the elastic support structure. The control base 9 is provided with a hemostatic valve 91 connected to the end of the inner tube 1. The control base 9 is convenient for operators to rotate or push and pull the inner tube 1. The addition of the hemostatic valve 91 can prevent blood from flowing out of the body through the lumen of the inner tube 1. The control base 9 is provided with a limit buckle 92. The limit buckle 92 can limit the distance that the outer tube 2 moves forward and backward relative to the inner tube 1, thereby preventing surgical hazards caused by excessive relative sliding between the outer tube 2 and the inner tube 1.

[0070] like Figure 9-10As shown, a locking structure is provided between the outer tube 2 and the inner tube 1, and the locking structure can control the switching between the inner tube 1 and the outer tube 2 between the locked state and the unlocked state. When the elastic supporting structure is in the storage state or the released state relative to the outer tube 2, the inner tube 1 and the outer tube 2 can be locked and fixed by using the locking structure, so that the inner tube 1 and the outer tube 2 remain fixed to prevent the inner tube 1 and the outer tube 2 from sliding against each other; the locking structure includes a positioning seat 5, a screw sleeve 6, an annular pressing block 7 and a hose 8, the positioning seat 5 is provided with a channel 5a axially through it, one end of the outer tube 2 is fixedly connected to the positioning seat 5, so that the lumen of the outer tube 2 is connected to the channel 5a, the hose 8 is sleeved on the outside of the outer tube 2, the positioning seat 5 is threadedly connected to the screw sleeve 6, the screw sleeve 6 is provided with a pressing portion 61, the annular pressing block 7 and the hose 8 are coaxially penetrated in the channel 5a The pressing portion 61 is pressed and matched with the annular pressing block 7, and drives the rubber tube 8 to elastically deform radially inward. The pressing portion 61 is moved closer to or away from the annular pressing block 7 by rotating the screw sleeve 6 relative to the positioning seat 5. When the pressing portion 61 presses the annular pressing block 7, the annular pressing block 7 presses the rubber tube 8 downward. At this time, since the rubber tube 8 is restricted by the inner wall of the channel 5a of the positioning seat 5 on all sides, the rubber tube 8 can only be elastically deformed inward after being squeezed, thereby pressing the outer tube 2 and locking with the inner tube 1. When the pressing portion 61 is away from the annular pressing block 7, the pressing force of the annular pressing block 7 on the rubber tube 8 disappears, and the rubber tube 8 resets upward by its own elastic restoring force, so that the channel 5a is conductive. In this way, the locking between the outer tube 2 and the inner tube 1 is achieved by rotating the screw sleeve 6 and using the annular pressing block 7 to press the rubber tube 8 inward to deform it.

[0071] like Figure 3As shown, the self-expanding stent 3 is configured as a spring spiral tube 31 with radial elasticity and stretchability made by spirally winding a metal wire. When the spring spiral tube 31 extends out of the outer tube 2, the radial expansion force of the spring spiral tube 31 can automatically expand the self-expanding stent 3 outward, so that the outer wall of the spring spiral tube 31 and the inner wall of the pulmonary artery are supported and positioned to prevent the guide sheath from slipping relative to the pulmonary artery. In addition, the spring spiral tube 31 also has a circumferential elastic expansion force, so that the spring spiral tube 31 can be axially deformed when switching between the storage state and the release state; in addition, the pitch of the spring spiral tube 31 in the release state forms a gap for blood circulation, which can ensure the circulation of blood in the pulmonary artery; the spring spiral tube 31 includes an integrally coiled arrangement The connecting spiral portion 311 and the supporting spiral portion 312, one end of the connecting spiral portion 311 is fixedly connected to the end of the inner tube 1, the diameter of the supporting spiral portion 312 is equal, and the diameter of the connecting spiral portion 311 gradually decreases from the end close to the supporting spiral portion 312 to the end away from the supporting spiral portion 312. Relying on the setting of the connecting spiral portion 311 with a gradually decreasing diameter, the process of the connecting spiral portion 311 being retracted into the lumen of the outer tube 2 is smoother. In addition, the supporting spiral portion 312 with the same diameter can also be against the inner wall of the pulmonary artery after being unfolded, thereby ensuring the firm positioning between the spring spiral tube 31 and the pulmonary artery after release; the diameter of the metal wire is set between 0.1-2mm, and the number of turns of the metal wire of the spring spiral tube 31 is set between 2-20 turns.

[0072] The basic working principle of the present invention is as follows: in the initial state, the inner tube 1 and the elastic support structure are wrapped in the lumen of the outer tube 2, at which time the elastic support structure is in a retracted state, and the locking structure is in a locked state; the guide sheath with the elastic support structure in the retracted state is extended into the pulmonary artery and reaches the expected surgical focus position near the disease; the locking structure is switched to the unlocked state by rotating the screw cap, and the outer tube 2 is pulled back relative to the inner tube 1 toward the outside of the human body by a predetermined length, so that the elastic support structure at the end of the inner tube 1 extends from the front end of the outer tube 2, and at this time the elastic support structure is expanded radially outward by its own elastic expansion force, so that the outer wall of the elastic support structure can be aligned with the pulmonary artery. The inner wall of the pulmonary artery is elastically supported to achieve positioning; when the elastic support structure is positioned in coordination with the pulmonary artery, the gap of the elastic support structure in the released state is used to achieve continuous blood circulation, and the locking structure is switched to the locked state by rotating the screw cap in the reverse direction, so that the inner tube 1 and the outer tube 2 are locked and fixed to prevent the inner tube 1 and the outer tube 2 from moving relative to each other during the interventional surgery; the interventional surgery is performed using the guide sheath in the positioning state with the inner wall of the pulmonary artery; the screw cap is rotated to switch the locking structure to the unlocked state, and the outer tube 2 is pushed relative to the inner tube 1 into the human body by a predetermined length, so that the elastic support structure is elastically deformed and compressed and stored in the outer The elastic support structure is stored in the lumen of tube 2; the locking structure is switched to the locking state by rotating the screw cap in the opposite direction again, and the guide sheath is withdrawn from the human body as a whole; the radial expansion force of the elastic support structure in the released state is used to elastically support the inner wall of the blood vessel, so as to realize the support positioning between the end of the guide sheath and the inner wall of the blood vessel, which can effectively prevent the guide sheath from being displaced or separated from the blood vessel due to the pulling or pushing force along the length direction of the blood vessel during the operation using the guide sheath, thereby ensuring the smooth progress of the pulmonary artery intervention operation; and the elastic support structure and the inner tube 1 and the outer tube 2. Always maintain a high degree of concentricity so that the guide sheath is always in the center of the blood vessel during the interventional treatment, which is conducive to the penetration of the interventional device and greatly reduces the possibility of contact between the interventional device and the blood vessel wall. It can greatly reduce the rupture and damage of the blood vessel wall during the process of the interventional device passing through the guide sheath into the pulmonary artery or being withdrawn from the pulmonary artery. It has the effect of preventing the guide sheath from falling off, saving operation time, and the guide sheath is always in the center position relative to the pulmonary artery to ensure the smooth penetration and withdrawal of the interventional device, and greatly reducing the rupture and damage of the blood vessel wall during the penetration and withdrawal of the interventional device.

[0073] The present invention provides a method for releasing and recovering a guide sheath of a pulmonary artery guide sheath, comprising the following steps:

[0074] S1: In the initial state, the inner tube and the elastic support structure are wrapped in the lumen of the outer tube, at which time the elastic support structure is in a retracted state, and the locking structure is in a locked state;

[0075] S2: Extend the introducer sheath with the elastic support structure in the retracted state into the pulmonary artery and reach the expected surgical focus near the lesion;

[0076] S3: rotating the screw cap to switch the locking structure to the unlocking state, pulling the outer tube back relative to the inner tube to a predetermined length outside the human body, so that the elastic support structure at the end of the inner tube extends from the front end of the outer tube. At this time, the elastic support structure uses its own elastic expansion force to expand radially outward, so that the outer wall of the elastic support structure can be positioned with the inner wall elastic support of the pulmonary artery;

[0077] S4: When the elastic support structure is positioned and matched with the pulmonary artery, the gap of the elastic support structure in the released state is used to realize the continuous circulation of blood, and the locking structure is switched to the locked state by rotating the screw cap in the reverse direction, so that the inner tube and the outer tube are locked and fixed to prevent the inner tube and the outer tube from moving relative to each other during the interventional surgery;

[0078] S5: Interventional surgery is performed using an introducer sheath that is positioned with the inner wall of the pulmonary artery.

[0079] S6: rotating the screw cap to switch the locking structure to an unlocked state, pushing the outer tube relative to the inner tube toward the human body by a predetermined length, driving the elastic support structure to undergo elastic deformation and be compressed and stored in the lumen of the outer tube, thereby achieving storage of the elastic support structure;

[0080] S7: Rotate the screw cap in the reverse direction again to switch the locking structure to the locked state, and withdraw the guide sheath as a whole from the human body.

[0081] In the above-mentioned method for releasing and recovering the guide sheath, the outer wall of the elastic support structure can be elastically supported by the inner wall of the pulmonary artery to achieve positioning, thereby preventing the inner tube from slipping toward the heart relative to the pulmonary artery during surgical treatment assisted by the guide sheath, thereby effectively avoiding stimulation of the heart to cause ventricular damage, palpitations, atrial fibrillation, heartbeat disorder and other serious clinical side effects. It should also be pointed out that in the present invention, the predetermined length of the outer tube moving relative to the inner tube toward the inside or outside of the human body just meets the release and storage of the elastic support structure. Specific embodiment 2

[0083] A pulmonary artery introducer sheath, such as Figure 4As shown, the difference between this embodiment and the specific embodiment 1 is that: the self-expanding stent 3 includes a plurality of layers of braided mesh tubes 32 woven by braided wires, and a plurality of quadrilateral units are formed on the surface of the braided mesh tube 32. The plurality of quadrilateral units cooperate to improve the elastic deformation capacity of the braided mesh tube 32. The side wall of the braided mesh tube after expansion can be against the inner wall of the pulmonary artery blood vessel to achieve positioning. In addition, the mesh of the braided mesh tube 32 after expansion can allow blood to flow in the blood vessel; the braided mesh tube 32 includes at least one radial expansion portion 320. When the elastic support structure is in a released state, the radial expansion portion 320 automatically expands outward into a disc shape The disc-shaped radial expansion portion 320 after expansion can be abutted against the inner wall of the pulmonary artery to achieve positioning. In addition, the outer edge of the disc-shaped radial expansion portion 320 is in a circular arc transition, which is different from the outer edge setting of the radial expansion portion 320 with a sharp edge. The outer edge of the radial expansion portion 320 of this embodiment adopts an arc transition setting, so that the outer wall of the radial expansion portion 320 fits more safely with the inner wall of the blood vessel; the braiding wire of the braided mesh tube 32 is woven with a polymer material, and the number of braided strands of the braided mesh tube 32 is set between 2-128, and the braiding density of the braided mesh tube 32 is set between 10-1000PPI.

[0084] The other structures of this embodiment are consistent with those of the first embodiment and will not be described in detail here. Specific embodiment three

[0086] A pulmonary artery introducer sheath, such as Figure 5-7 As shown, the difference between this embodiment and the specific embodiment 1 is that the self-expanding stent 3 includes a plurality of layers of braided mesh tubes 32 woven by braided wires, the braided mesh tube 32 includes a braided support portion 321 and a braided connection portion 322 that are integrally woven, one end of the braided connection portion 322 is fixedly connected to the end of the inner tube 1, the diameters of the braided support portions 321 are equal, and the diameter of the braided connection portion 322 gradually decreases from one end close to the braided support portion 321 to the end away from the braided support portion 321, and the braided connection portion 322 is gradually reduced in diameter, so that the braided connection portion 322 is The process of the connecting part 322 being retracted into the lumen of the outer tube 2 is smoother. In addition, the braided support part 321 with the same diameter can also be against the inner wall of the pulmonary artery after being unfolded, thereby ensuring the firm positioning between the braided mesh tube 32 and the pulmonary artery after release. The braiding wire of the braided mesh tube 32 is woven from a plurality of metal wires, and the metal wire material is any one of medical metal materials such as nickel-titanium alloy, platinum-tungsten alloy, etc. with certain elasticity, and the number of metal wire strands of each braided wire is set between 2-128, and the diameter of the metal wire is set between 0.01-10mm.

[0087] The other structures of this embodiment are consistent with those of the first embodiment and will not be described in detail here. Specific embodiment 4

[0089] A pulmonary artery introducer sheath, such as Figure 8 As shown, the difference between this embodiment and the specific embodiment three is that the elastic support structure also includes a layer of elastically stretchable coating film 4 wrapped around the braided mesh tube 32. The coating film 4 can prevent the braided wire of the braided mesh tube 32 from squeezing and scratching the inner wall of the pulmonary artery. In addition, due to the mesh of the braided mesh tube, there is a gap between the mesh position of the coating film 4 and the inner wall of the pulmonary artery, and the gap allows blood to pass through. The coating film 4 is made of one or more materials selected from polytetrafluoroethylene, polyester, polyester, and polyurethane, and the thickness of the coating film 4 is set between 0.1-2mm. The coating film 4 prepared using polytetrafluoroethylene, polyester, polyester, and polyurethane can play a good lubricating and protective role on the inner wall of the blood vessel.

[0090] The other structures of this embodiment are consistent with those of the third embodiment and will not be described again here.

[0091] The above description is only a preferred embodiment of the present invention, so all equivalent changes or modifications made according to the structure, characteristics and principles described in the scope of the patent application of the present invention are included in the scope of the patent application of the present invention.

Claims

1. A pulmonary artery guide sheath, characterized in that: The invention comprises an inner tube (1) and an outer tube (2), wherein the inner tube (1) is movably inserted into the outer tube (2), and an elastic support structure is provided at the front end of the inner tube (1). The inner tube (1) and the outer tube (2) can move relative to each other, so as to drive the elastic support structure to switch between a storage state and a release state relative to the outer tube (2); When the elastic support structure is in a retracted state, the elastic support structure is retracted into the lumen of the outer tube (2); When the elastic support structure is in a released state, the elastic support structure is radially expanded outward and cooperates with the blood vessel wall support positioning, and the elastic support structure in the released state is provided with a gap for blood circulation.

2. A pulmonary artery guide sheath according to claim 1, characterized in that: The elastic support structure comprises a self-expanding stent (3) having a radial expansion force, and the outer tube (2) has a radial restraining force. When the elastic support structure is in a retracted state, the outer tube (2) wraps the inner tube (1) and the self-expanding stent (3) therein by means of the radial restraining force.

3. A pulmonary artery guide sheath according to claim 2, characterized in that: The self-expanding stent (3) is a spring spiral tube (31) made by spirally winding a metal wire and having radial elasticity and stretchability.

4. A pulmonary artery guide sheath according to claim 3, characterized in that: The spring spiral tube (31) comprises a connecting spiral portion (311) and a supporting spiral portion (312) which are arranged in an integral manner, one end of the connecting spiral portion (311) is fixedly connected to the end of the inner tube (1), the diameters of the supporting spiral portions (312) are equal, and the diameter of the connecting spiral portion (311) gradually decreases from an end close to the supporting spiral portion (312) to an end away from the supporting spiral portion (312).

5. A pulmonary artery guide sheath according to claim 3, characterized in that: The diameter of the metal wire is set between 0.1 and 2 mm, and the number of turns of the metal wire of the spring spiral tube (31) is set between 2 and 20.

6. A pulmonary artery guide sheath according to claim 2, characterized in that: The self-expanding stent (3) comprises a plurality of layers of braided mesh tubes (32) braided from braided wires.

7. A pulmonary artery guide sheath according to claim 6, characterized in that: The braided mesh tube (32) comprises at least one radial expansion portion (320), and when the elastic support structure is in a released state, the radial expansion portion (320) automatically expands outward into a disc shape.

8. A pulmonary artery introducer sheath according to claim 6, characterized in that: The braided wire of the braided mesh tube (32) is braided with a polymer material, the number of braided strands of the braided mesh tube (32) is set between 2 and 128, and the braiding density of the braided mesh tube (32) is set between 10 and 1000 PPI.

9. A pulmonary artery guide sheath according to claim 6, characterized in that: The braided mesh tube (32) comprises a braided support portion (321) and a braided connection portion (322) which are integrally braided and formed, one end of the braided connection portion (322) being fixedly connected to the end of the inner tube (1), the diameters of the braided support portions (321) being equal, and the diameter of the braided connection portion (322) gradually decreasing from an end close to the braided support portion (321) toward an end away from the braided support portion (321).

10. A pulmonary artery introducer sheath according to claim 9, characterized in that: The braided wire of the braided mesh tube (32) is braided from a plurality of metal wires, the metal wire material being any one of elastic medical metal materials such as nickel-titanium alloy and platinum-tungsten alloy, and the number of metal wire strands of each braided wire is set between 2 and 128, and the diameter of the metal wire is set between 0.01 and 10 mm.

11. A pulmonary artery introducer sheath according to claim 8, characterized in that: The elastic support structure also includes a layer of coating film (4) with elastic stretchability wrapped outside the braided mesh tube (32).

12. A pulmonary artery introducer sheath according to claim 11, characterized in that: The coating film (4) is made of one or more materials selected from the group consisting of polytetrafluoroethylene, dacron, polyester, and polyurethane, and the thickness of the coating film (4) is set between 0.1 and 2 mm.

13. A pulmonary artery introducer sheath according to claim 1, characterized in that: One end of the elastic support structure is connected to the end of the inner tube (1) by welding or fasteners.

14. A pulmonary artery introducer sheath according to claim 1, characterized in that: A locking structure is provided between the outer tube (2) and the inner tube (1), and the locking structure can control the inner tube (1) and the outer tube (2) to switch between a locked state and an unlocked state.

15. A pulmonary artery introducer sheath according to claim 14, characterized in that: The locking structure comprises a positioning seat (5), a screw sleeve (6), an annular pressure block (7) and a rubber tube (8); the positioning seat (5) is provided with a channel (5a) extending through the positioning seat along the axial direction; one end of the outer tube (2) is fixedly connected to the positioning seat (5) so that the lumen of the outer tube (2) is communicated with the channel (5a); the rubber tube (8) is sleeved outside the outer tube (2); the positioning seat (5) is threadedly connected to the screw sleeve (6); the screw sleeve (6) is provided with a pressing portion (61); the annular pressure block (7) and the rubber tube (8) are coaxially inserted into the channel (5a); the pressing portion (61) is pressed and matched with the annular pressure block (7) and drives the rubber tube (8) to elastically deform radially inward.

16. A pulmonary artery introducer sheath according to claim 1, characterized in that: A control base (9) is provided at one end of the inner tube (1) away from the elastic support structure, and the control base (9) is provided with a hemostatic valve (91) connected to the end of the inner tube (1).

17. A pulmonary artery introducer sheath according to claim 16, characterized in that: The control base (9) is provided with a limit buckle (92).

18. A method for releasing and recovering a pulmonary artery guide sheath according to any one of claims 1 to 17, characterized in that: The following steps are involved: S1: In the initial state, the inner tube and the elastic support structure are wrapped in the lumen of the outer tube, and the elastic support structure is in a retracted state; S2: Extend the introducer sheath with the elastic support structure in the retracted state into the pulmonary artery and reach the expected surgical focus near the lesion; S3: Pull the outer tube back to a predetermined length relative to the inner tube toward the outside of the human body, so that the elastic support structure at the end of the inner tube extends out from the front end of the outer tube. At this time, the elastic support structure uses its own elastic expansion force to expand radially outward, so that the outer wall of the elastic support structure can be positioned with the inner wall elastic support of the pulmonary artery; S4: When the elastic support structure is positioned and matched with the pulmonary artery, the gap of the elastic support structure in the released state is used to achieve continuous blood circulation; S5: Interventional surgery is performed using an introducer sheath that is positioned with the inner wall of the pulmonary artery. S6: pushing the outer tube relative to the inner tube toward the human body by a predetermined length, driving the elastic support structure to undergo elastic deformation and be compressed and stored in the lumen of the outer tube, thereby achieving storage of the elastic support structure; S7: Withdraw the introducer sheath.

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