WO2022142663A1

WO2022142663A1 - Endocardial injection device and endocardial injection system

Info

Publication number: WO2022142663A1
Application number: PCT/CN2021/127124
Authority: WO
Inventors: Tingchao ZHANG; Yang Li; Zhenping Zhuang; Bobo Peng
Original assignee: Hangzhou Valgen Medtech Co., Ltd.
Priority date: 2020-12-30
Filing date: 2021-10-28
Publication date: 2022-07-07

Abstract

Disclosed is an endocardial injection device and an endocardial injection system. The endocardial injection device comprises: asleeve provided with a limiter at an inside distal end thereof; and an injection assembly slidably provided within the sleeve, aproximal end of the injection assembly is connected to an injection tube, and a distal end of the injection assembly pierces the limiter, wherein a proximal end of the limiter comprises a thrust surface in movable abutment with the injection assembly, and a distal end of the limiter is provided with a contact surface; the contact surface is provided with at least one first through hole, an inner wall of the sleeve is provided with at least one second through hole, and the first through hole and the second through hole are in fluid communication.

Description

ENDOCARDIAL INJECTION DEVICE AND ENDOCARDIAL INJECTION SYSTEM

CROSS-REFERENCE TO RELATED APPLICATIONS

The present disclosure claims all the benefits of the Chinese patent application No. 202011614657.9, filed on December 30, 2020 before the China National Intellectual Property Administration of the People’s Republic of China, entitled “Endocardial Injection Device and Endocardial Injection System” , and the Chinese Utility Model application No. 202023335527. X, filed on December 30, 2020 before the China National Intellectual Property Administration of the People’s Republic of China, entitled “Endocardial Injection Device and Endocardial Injection System” , which are explicitly incorporated herein by reference in their entirety.

FIELD

The present disclosure generally relates to a field of medical devices, in particular to an endocardial injection device and an endocardial injection system.

BACKGROUND

Myocardial infarction, chronic heart failure, myocarditis, and cardiac conduction system diseases seriously affect life quality and lifetime of people. Research data has shown that localized or diffuse necrosis and fibrosis occurred in myocardial cells may lead to decreased heart function, while mature myocardial cells lack regeneration capacity. At present, clinic lacks of fundamental therapeutic methods against myocardial regeneration and blood vessel reconstruction, but cell replacement therapy emerges and brings hope for patients of various advanced heart diseases. Cell replacement therapy refers to treatment methods in which pathological and injured cells in the body are replaced with functional normal cells, factors, drugs, and the like, thereby achieving function repair. One of critical steps in cell replacement therapy for myocardial regeneration is a pathway of implanting cells, factors, drugs, and the like into myocardium, and clinical research suggests that an endocardial injection method can make drugs and transplants easier to directly enter a target region without travelling a long distance, which is more conducive to the role of chemokines.

SUMMARY

In one aspect, the present disclosure relates to an endocardial injection device comprising:

a sleeve, the sleeve provided with a limiter at an inside distal end thereof; and

an injection assembly slidably provided within the sleeve, a proximal end of the injection assembly is connected to an injection tube, and a distal end of the injection assembly pierces the limiter, wherein

a proximal end of the limiter comprises a thrust surface in movable abutment with the injection assembly, and a distal end of the limiter is provided with a contact surface; the contact surface is provided with at least one first through hole, an inner wall of the sleeve is provided with at least one second through hole, and the first through hole and the second through hole are in fluid communication.

In some embodiments, the contact surface of the limiter is provided with a needle hole through which the injection assembly passes, and the thrust surface is provided at a proximal end of the needle hole.

In some embodiments, a sum of a cross-sectional area of the first through hole is greater than or equal to a sum of a cross-sectional area of the second through hole.

In some embodiments, the injection assembly comprises a needle hub and a needle tube, a distal end of the needle tube is provided with a tip, the needle hub comprises a needle tube connecting segment, a guide segment, and an injection tube connecting segment from the distal end to the proximal end, the needle tube connecting segment is fixed to a proximal end of the needle tube, and the guide segment movably abuts the thrust surface.

In some embodiments, the guide segment comprises a number of guide portions provided on a periphery of the needle tube, the guide portions extend along an axial direction of the needle tube, and a notch is formed between adjacent guide portions.

In some embodiments, the tip of the needle tube comprises a first inclined plane and two second inclined planes symmetrically provided on both sides of the first inclined plane, and the two second inclined planes extend to a distal end to form a puncturing tip.

In some embodiments, an angle between the puncturing tip and the axial direction of the needle tube ranges from 11° to 30°, an angle between the first inclined plane and the axial direction of the needle tube ranges from 11° to 20°, and an angle between each of the second inclined planes and the axial direction of the needle tube ranges from 11° to 45°.

In some embodiments, the injection tube comprises a first passage and a second passage, and the first passage and the second passage are provided side by side or coaxially along the axial direction.

In some embodiments, the distal end of the sleeve comprises a limiter mounting segment that is in interference fit with the limiter.

In some embodiments, the sleeve further comprises a body segment and a delivery catheter connecting segment connected to a proximal end of the limiter mounting segment, and the delivery catheter connecting segment has a size smaller than a size of the body segment.

In another aspect, the present disclosure relates to an endocardial injection system comprising an operation handle, a delivery catheter, and the endocardial injection device with the above structure, wherein the injection tube passes through the delivery catheter, a proximal end of the sleeve is fixedly connected to a distal end of the delivery catheter, and the operation handle drives the injection tube to drive the injection assembly to move axially, so that the injection assembly extends from or retracts into the sleeve.

In some embodiments, a proximal end of the operation handle comprises an injection portion in communication with the injection tube.

In some embodiments, the operation handle further comprises a drive portion, wherein the drive portion is connected to a proximal end of the injection tube, and rotation of the drive portion drives the injection tube and the injection assembly to spirally move along an axial direction of the sleeve.

In some embodiments, the operation handle is further provided with a fluid guide port in communication with the delivery catheter, and the fluid guide port is provided with a valve body for controlling on-off of the fluid guide port.

In another aspect, the present disclosure relates to an endocardial injection method comprising:

puncturing a guide sheath from a femoral artery into a body to reach a left ventricle via an aortic arch;

inserting a delivery catheter sleeved with an adjustable sheath into the body along an inner cavity of the guide sheath to the left ventricle;

adjusting a distal surface of the endocardial injection device with the above structure to substantially perpendicular to a free wall of the left ventricle under aid of the guide sheath and the adjustable sheath;

advancing the endocardial injection device slowly, and determining whether the endocardial injection device abuts the free wall by a motion state of the delivery catheter connected to a sleeve under guide of angiography or ultrasonography;

opening a valve body of a fluid guide port at a proximal end of an operation handle, and flowing contrast media through the delivery catheter surrounding an injection tube when the endocardial injection device has fit the free wall;

driving a drive portion on the operation handle to cause a needle tube to puncture the free wall when the device is in tight touch with the free wall;

injecting an appropriate amount of contrast media into the injection tube by an injection portion of the operation handle; and

retracting the needle tube into the sleeve after completing the injection.

In the endocardial injection device and the endocardial injection system of the present disclosure, the endocardial injection device comprising a sleeve and an injection assembly, the injection assembly is slidably disposed within the sleeve, a limiter is provided at an inside distal end of the sleeve, and when the injection assembly moves to the thrust surface of the limiter, the limiter enables a limit on the injection assembly to control the maximum depth at which the injection assembly punctures the ventricular wall. In addition, since the endocardium itself may change the location with beating of the heart, a fitting state of the contact surface of the limiter of the injection device with the ventricular wall may be determined by a flowing state of the contrast media within the sleeve before injection, thereby avoiding puncturing error or drug contamination; when the contrast media is ejected from the first through hole of the contact surface of the limiter, the injection assembly does not fit or fully fit the ventricular wall; when the contrast media only flows from the second through hole of the sleeve but is not ejected from the first through hole of the limiter, the injection assembly fully fits the ventricular wall, thereby enabling the injection assembly to puncture a proper site of the endocardium to reduce unnecessary injury to the endocardium. In the present disclosure, an extension length of the injection assembly is controlled by the limiter inside the device, a fit state with the ventricular wall is determined and adjusted by the contact surface of the limiter outside the device, and the inside and outside limiting controls enable precise control of the depth or injection site at which the injection assembly ultimately punctures the ventricular wall, achieving surgical effects of controllable injection and reduced injury.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 is an overall view of an endocardial injection system of an example of the present disclosure.

Fig. 2 is a longitudinal cross-sectional view of an endocardial injection device of an example of the present disclosure in a retracted state.

Fig. 3 is a longitudinal cross-sectional view of an endocardial injection device of an example of the present disclosure in an extended state.

Fig. 4 is a schematic structural view of an endocardial injection device of an example of the present disclosure puncturing a ventricular wall.

Fig. 5 is a structure exploded view of an endocardial injection device of an example of the present disclosure.

Fig. 6 is a perspective view of a limiter of an example of the present disclosure.

Fig. 7 is a front cross-sectional parameter view of a limiter of an example of the present disclosure.

Fig. 8 is a front view of a sleeve of an example of the present disclosure.

Fig. 9 is a front cross-sectional view of a sleeve of an example of the present disclosure.

Fig. 10 is a front cross-sectional view of a needle hub of an example of the present disclosure.

Fig. 11 is a front view of a needle hub of an example of the present disclosure.

Fig. 12 is a front cross-sectional parameter view of a needle hub of an example of the present disclosure.

Fig. 13 is a right view of a needle hub of an example of the present disclosure.

Fig. 14 is a perspective view of a needle tube of an example of the present disclosure.

Fig. 15 is an oblique parameter view of a needle tube of an example of the present disclosure.

Fig. 16 is a rear parameter view of a needle tube of an example of the present disclosure.

Fig. 17 is a left view of a needle tube of an example of the present disclosure.

Fig. 18 is a schematic diagram of a needle tube of an example of the present disclosure puncturing a ventricular wall.

Fig. 19 is a longitudinal cross-sectional view of an injection assembly of an example of the present disclosure.

Fig. 20 is a right view of Fig. 19.

Fig. 21 is a longitudinal cross-sectional view of an injection assembly of another example of the present disclosure.

Figs. 22 to 28 are schematic diagrams illustrating a process of using an endocardial injection system of the present disclosure for endocardial injection, wherein:

Fig. 22 is a schematic diagram showing that a guide sheath enters a heart via an aortic arch and establishes a path.

Fig. 23 is a schematic diagram showing that an endocardial injection device reaches an expected site along the guide sheath.

Fig. 24 is a schematic diagram showing that a distal surface of the endocardial injection device is adjusted to be substantially perpendicular to a ventricular wall.

Fig. 25 is a schematic diagram showing that the endocardial injection device uses contrast media for wall touch determination.

Fig. 26 is a schematic diagram showing that the endocardial injection device uses a limiter to control an injection depth.

Fig. 27 is a schematic diagram showing that the endocardial injection device injects hydrogel into the ventricular wall after determining a correct site using the contrast media.

Fig. 28 is a schematic diagram showing that a needle tube is retracted into a sleeve after the endocardial injection device completes injection.

DETAILED DESCRIPTION

To make the objects, technical solutions, and advantages clearer, the technical solutions of the present disclosure are described below clearly and completely with reference to the drawings. Obviously, the described are only part of examples of the present disclosure, rather than all of the examples. Based on the examples in the present disclosure, all other examples obtained by one skilled in the art without involving inventive work fall within the protection scope of the present disclosure.

In the present disclosure, an orientation or position relationship indicated by “front” , “back” , “upper” , “lower” , “left” , “right” , “longitudinal” , “transverse” , “vertical” , “horizontal” , “top” , “bottom” , “inner” , “outer” , “head” , “tail” , and the like is an orientation or position relationship shown in the drawings, and construction and operation in a specific orientation is merely for convenience of describing the present technical solutions, rather than indicating that the device or element referred to must have a specific orientation, and thus should not be construed as limiting the present disclosure.

In the present disclosure, terms such as “mount” , “connected to” , “connect” , “fix” , “dispose” , and the like should be understood broadly unless expressly specified or defined. For example, it may be a fixed connection, a detachable connection, or an integration; it may be a direct connection, an indirect connection by an intermediary, or an internal communication or interaction relationship between two elements. When an element is referred to as being “above” or “under” another element, the element may be “directly” or “indirectly” on another element, or there may be one or more intervening elements. Specific meanings of the above terms in the present disclosure can be understood by one skilled in the art in light of specific circumstances.

In description of the present disclosure, it should still be noted that a proximal end refers to an end of a device or component near an operator, and a distal end refers to an end of the device or component away from the operator; and an axial direction refers to a direction parallel to a center line between the distal end and the proximal end of the device or component, a radial direction refers to a direction perpendicular to the axial direction, and a circumferential direction refers to a direction around the axial direction.

This is to overcome the defect in the prior art that the injection device that uses a screw for endocardial injection cannot precisely control a puncturing depth while causing large injury to the endocardium. The present disclosure exemplarily discloses an endocardial injection device for injecting a drug or graft into the endocardium, facilitating regeneration and function repair of diseased and injured myocardial cells in the heart, thereby treating heart diseases such as necrosis of the myocardial cells, myocardial infarction resulting from fibrosis, and chronic heart failure. Examples of the present disclosure are described in detail below with reference to the drawings.

Referring to Figs. 1 to 7, the endocardial injection device 100 comprises a sleeve 110 and an injection assembly 130. A limiter 120 is provided at the inner distal end of the sleeve 110. The injection assembly 130 is slidably provided within the sleeve 110, the proximal end of the injection assembly 130 is connected to an injection tube 210, and the distal end of the injection assembly 130 pierces the limiter 120. The proximal end of the limiter 120 comprises a thrust surface 121 in movable abutment with the injection assembly 130, the distal end of the limiter 120 is provided with a contact surface 122, and the contact surface 122 is provided with at least one first through hole 123 (referring to Figs. 6 and 7) . The inner wall of the sleeve 110 is provided with at least one second through hole 114 (referring to Fig. 5) , and the first through hole 123 is in fluid communication with the second through hole 114.

In some embodiments, the injection assembly 130 serves to puncture the ventricular wall 561, and the drug, graft, or the like in the injection tube 210 enters the ventricular wall 561 through the injection assembly 130. The ventricular wall 561 comprises an endocardium, a myocardium, and an epicardium from inside to outside, and the injection assembly 130 enters the ventricle through a passage and injects the drug or graft to the myocardium from inside to outside. The injection assembly 130 is slidably provided within the sleeve 110, the limiter 120 is provided within the sleeve 110, and when the injection assembly 130 moves to the thrust surface 121 of the limiter 120, the limiter 120 realizes limit of the injection assembly 130 to control the maximum depth at which the injection assembly 130 punctures the ventricular wall 561. To further ensure a limiting effect of the limiter 120, at least a part of the thrust surface 121 should match a corresponding contact position of the injection assembly 130 to form line contact or face contact.

In some embodiments, referring to Fig. 4, the contact surface 122 fits the ventricular wall 561 and provides a force bearing carrier for the injection assembly 130, so that the injection assembly 130 remains stable during injection. In addition, since the endocardium itself may change its position with the beating of the heart, a fitting state of the contact surface 122 of the limiter 120 of the endocardial injection device 100 with the ventricular wall 561 may be determined by a flowing state of the contrast media within the sleeve 110 before injection, thereby avoiding puncturing error or drug contamination. When the contrast media is ejected from the first through hole 123 of the contact surface 122 of the limiter 120, the injection assembly 130 does not fit or fully fit the ventricular wall 561; when the contrast media only flows from the second through hole 114 of the sleeve 110 but is not ejected from the first through hole 123 of the limiter 120, the injection assembly 130 fully fits the ventricular wall 561, thereby enabling the injection assembly 130 to puncture a proper site of the endocardium to reduce unnecessary injury to the endocardium.

In some embodiments, an extension length of the injection assembly 130 is controlled by the limiter 120 inside the device 100, a fit state with the ventricular wall 561 is determined and adjusted by the contact surface 122 of the limiter 120 outside the device, and the inside and outside limiting controls enable precise control of the depth or injection site at which the injection assembly 130 ultimately punctures the ventricular wall 561, achieving surgical effects of controllable injection and reduced injury.

In some embodiments, referring to Figs. 6 and 7, the limiter 120 comprises an arc segment 1201 primarily for reducing injury thereto when the device is in contact with the ventricular wall 561 and a sleeve connecting segment 1202 primarily for connecting with the sleeve 110. In some embodiments, the outer end surface of the arc segment 1201 is the contact surface 122, the contact surface 122 is provided with a needle hole 124 through which the injection assembly 130 passes, and the needle hole 124 serves to allow the injection assembly 130 to pass through along the puncturing direction, and the proximal end of the needle hole 124 is provided with the thrust surface 121. The thrust surface 121 and the contact surface 122 are respectively located at both ends of the needle hole 124, so that the limiting direction of the thrust surface 121 is opposite to the fitting direction of the contact surface 122. The thrust surface 121 and the contact surface 122 of the limiter 120 interact with the injection assembly 130 and the ventricular wall 561 respectively to ensure that the limiter 120 always plays a limiting role during injection.

In some embodiments, the thrust surface 121 is a tapered surface with an angle that can reduce the risk of jamming resulting from abutment on the limiter 120 during pushout of the injection assembly 130 while forming a barrier and limit to the injection assembly 130. When the distal end of the injection assembly 130 touches the tapered surface of the thrust surface 121 and cannot move forward, the needle tube 132 just extends beyond the distal surface of the limiter 120 at a suitable puncturing depth. Moreover, a compression amount of such structure does not change with contraction of the heart, i.e., the puncturing depth of the needle tube 132 is always constant, which makes the drug less likely to leak.

In some embodiments, the at least one first through hole 123 is provided on the contact surface 122 between the needle hole 124 and the peripheral surface of the limiter 120 for quickly determining whether the entire device 100 is in tight touch with an endocardial free wall based on actual outflow of the contrast media from the through hole 123, typically with the cross-sectional area of the through hole 123 as a performance index. In some embodiments, the through hole 123 may be circular, square, or special-shaped, and with the circular shape as an example, the hole diameter is generally 0.5 mm to 1.0 mm, and other shapes are converted to equal cross-sectional areas. This example uses circular holes, and the number of the holes is 4. It can be understood that in other examples, the number of through holes may also be other positive integers greater than 1 such as 2, 3, and 5.

The material of the limiter 120 is associated with the connection means. In this example, the limiter 120 is connected to the sleeve 110 in a welding manner, so that the material of the limiter 120 may select a metal material, such as 304 stainless steel, 316 stainless steel, or Nitinol. 316 stainless steel is selected in this example.

Referring to Fig. 5 and Figs. 10 to 17, the injection assembly 130 comprises a needle hub 131 and a needle tube 132. The needle hub 131 comprises a needle tube connecting segment 1311, a guide segment 1312, and an injection tube connecting segment 1313 from the distal end to the proximal end. The distal end of the needle tube connecting segment 1311 is fixed to the proximal end of the needle tube 132 for connecting the needle tube 132; the guide segment 1312 movably abuts the thrust surface 121 for abutting against the thrust surface 121 of the limiter 120 to realize limiting; the injection tube connecting segment 1313 is used for communicating with the injection tube 210. The distal end of the needle tube 132 is provided with a tip 1320 for puncturing the ventricular wall 561; the proximal end of the needle tube 132 communicates with the injection tube 210 through the needle hub 131 to facilitate entry of the drug or graft into the needle tube 132 and final injection into the ventricular wall 561.

In some embodiments, the needle tube connecting segment 1311 is a cylinder with uniform wall thickness, and an inner hole is used for installing the needle tube 132. Therefore, an inner diameter d ₂ of the needle tube connecting segment 1311 is equal to the outer diameter of the needle tube 132 plus twice of a unilateral assembly gap. An outer diameter D ₂ and a length L ₂ of the needle tube connecting segment 1311 are related to the connection means. The connection needs to have sufficient connection strength and leak proofness, and thus use the means of whole circumference welding.

In some embodiments, the structure of the guide segment 1312 can be further adjusted. The guide segment 1312 comprises several guide portions 13121 provided at the periphery of the needle tube 132, the guide portions 13121 extends along the axial direction of the needle tube 132, with notches 13122 formed between adjacent guide portions 13121. The guide portion 13121 serves to abut and limit the inner wall of the sleeve 110, keep the needle tube 132 moving axially within the sleeve 110, and reduce radial run-out of the needle tube 132. The notch 13122 is used for passage of the contrast media, so that the contrast media can fill an inner cavity of the sleeve 110. The notch 13122 is in fluid communication with the first through hole 123 and the second through hole 114 to quickly determine whether the entire device 100 is completely in tight touch with the endocardial free wall based on actual outflow of the contrast media from the through hole. In some embodiments, the guide segment 1312 is a cylinder with an outer diameter of D ₃ and a length of L ₃ that is cut out with four axially symmetric notches 13122 being commonly circular, square, or special-shaped. The size of the notch 13122 only needs to meet the passage performance of the contrast media under the premise of ensuring a sufficiently large guide width.

In some embodiments, regarding an internal structure of the needle hub 131, the inner cavity is generally divided into four segments, a needle tube mounting cavity 1314, a positioning step 1315, a tapered cavity 1316, and an injection tube connecting cavity 1317. The needle tube mounting cavity 1314 serves to accommodate the needle tube 132. The positioning step 1315 serves to position the needle tube 132, so that an inner diameter d ₃ of the positioning step 1315 should be greater than or equal to an inner diameter d ₁ of the needle tube 132, and d ₃=d ₁ in this example. The tapered cavity 1316 serves to flow a fluid medium from the larger injection tube connecting cavity 1317 to the smaller needle tube mounting cavity 1314, and an angle δ thereof is theoretically as small as possible. However, the smaller the δ is, the longer the tapered cavity 1316 is, and the overlong tapered cavity 1316 is not conducive to downsize the product and decreasing assembly difficulty, so δ is typically between 30° and 60°, and δ=45° in this example. The injection tube connecting cavity 1317 serves to communicate with the injection tube 210. In this example, the needle hub 131 is connected to the needle tube 132 in a welding manner. The material of the needle hub 131 may select a metal material, such as 304 stainless steel, 316 stainless steel, or Nitinol, and 316 stainless steel is selected in this example.

In some embodiments, the needle tube 132 comprises a needle body 1324 having a length in addition to the tip 1320, and an end surface of the needle body 1324 is a plane perpendicular to the central axis. In the same case, the larger the inner diameter d ₁ of the different needle tubes 132, the lower the delivery resistance, but an increased outer diameter D ₁ results in an increase in a puncture area, which increases the risk of the injected fluid medium being back-leaked along a gap between a puncture surface and the outer surface of the needle tube 132 in addition to increasing the injury to the tissue. In general, the outer diameter D ₁ of a needle tube of an interventional injection system is between 0.4 mm and 0.7 mm, and taking small delivery resistance and low risk of back-leakage into account, the needle tube also needs to have certain anti-folding strength, D ₁=0.5 mm, and d ₁=0.35 mm in this example.

In some embodiments, the structure of the needle tube 132 is further adjusted. The tip 1320 of the needle tube 132 comprises a first inclined plane 1321 and two second inclined planes 1322 symmetrically provided on both sides of the first inclined plane 1321, and two second inclined planes 1322 extend to the distal end to form a puncturing tip 1323. During the puncturing process of the needle tube 132, the two second inclined planes 1322 first enter the ventricular wall 561, and as the puncturing depth increases, the first inclined plane 1321 then enters the ventricular wall 561. Since the first inclined plane 1321 smoothly transitions to the proximal ends of the two second inclined planes 1322, the needle body 1324 of the needle tube 132 smoothly punctures the ventricular wall 561 along the tip 1320, which causes little injury.

In some embodiments, an angle between the puncturing tip 1323 and the central axis of the needle body 1324 is θ, the smaller an angle α of the first inclined plane 1321, the longer the length L ₁ of the tip 1320, and θ ranges from 11° to 30°. The angle between the first inclined plane 1321 and the central axis of the needle body 1324 is α, which ranges from 11° to 20°. The angle and size of the second inclined plane 1322 directly affects the magnitude of a puncturing force, the angle between each second inclined plane 1322 and the central axis of the needle body 1324 is β, which ranges from 11° to 45°, and the angles satisfy α<θ. The basis for this setting is: the angle θ of the puncturing tip 1323 and the angle β of the two second inclined planes 1322 primarily affect the magnitude of the puncturing force of the needle tube 132, the smaller the angle θ of the puncturing tip 1323 and the larger the angle β of the second inclined plane 1322, the smaller the puncturing force of the needle tube 132 but the weaker the strength of the needle hub 131.

In some embodiments, referring to Fig. 18, a depth at which the needle tube 132 punctures the ventricular wall 561 is a puncturing depth H, and an effective depth h=H-L ₁. To prevent the needle tube 132 from piercing the ventricular wall 561, the puncturing depth H ranges from 3.5 mm to 4.5 mm, and H=4.0 mm in this example. Considering effects of the angle α of the first inclined plane 1321 and the angle β of the second inclined plane 1322 on the length L ₁ of the tip 1320 and the strength of the tip 1320, in a case where H=4 mm, to ensure a sufficient effective depth h, α=20°, θ=30°, and β=45° in this example.

In some embodiments, in addition to sufficient strength, the needle tube 132 needs to have certain ray detectability to assist the operator in identifying the location of the needle tube 132 and improving safety of the operation, and thus the material of the needle tube 132 may be 304 stainless steel, 316 stainless steel, Nitinol, or the like, and 316 stainless steel is selected in this example, and the needle hub 131 and the needle tube 132 may be made of the same material.

In some embodiments, the structure of the sleeve 110 can be further adjusted. Referring to Figs. 8 and 9, the distal end of the sleeve 110 comprises a limier mounting segment 111 that is in interference fit with the limiter 120. The interference fit between the sleeve 110 and the limiter 120 can effectively ensure that the limiter 120 remains relatively fixed with the sleeve 110, so that the limiter 120 can provide a stable support force for the injection assembly 130. In some embodiments, the sleeve connecting segment 1202 of the limiter 120 is in interference fit with the limiter mounting segment 111, the limiter mounting segment 111 is a cylinder with a uniform wall thickness, and an outer diameter D ₇ of the sleeve connecting segment 1202 of the limiter 120 is equal to an inner diameter d ₅ of the limiter mounting segment 111 of the sleeve 110 minus twice a unilateral assembly gap.

In some embodiments, the sleeve 110 further comprises a body segment 112 and a delivery catheter connecting segment 113 that are connected in sequence to the proximal end of the limiter mounting segment 111. In some embodiments, the body segment 112 and the delivery catheter connecting segment 113 are cylinders with a uniform wall thickness, and it is sufficient that the length of the body segment 112 can accommodate the needle tube 132 and the needle hub 131 while retaining a certain length of safe space. The inner diameter of the delivery catheter connecting segment 113 is smaller than the inner diameter of the body segment 112 to ensure smooth withdrawal of the device. The body segment 112 transitions to the delivery catheter connecting segment 113 in a tapered surface, the smaller an angle γ of the tapered surface, the longer the tapered surface, but the excessively long tapered surface affects bending properties of the product, so the angle γ is generally 30° to 60°. In some embodiments, the outer diameter D ₅ of the limiter mounting segment 111 is equal to the body segment 112. This example uses the fixing means of welding, and the delivery catheter connecting segment 113 may be adhesively fixed to a delivery catheter 200 using glue. In some embodiments, a connection hole 115 may be provided on the delivery catheter connecting segment 113 to facilitate glue connection.

In some embodiments, at least one second through hole 114 is provided on the circumferential side wall of the body segment 112 for passing the contrast media to quickly determine whether the entire device 100 is in tight touch with the endocardial free wall based on actual outflow of the contrast media from the through hole, typically with the cross-sectional area of the through hole as a performance index. In some embodiments, the second through hole 114 may be circular, square, or special-shaped, and with the circular shape as an example, the hole diameter is generally 0.5 mm to 1.0 mm, and other shapes are converted to equal cross-sectional areas. This example uses circular holes, the number of the holes is 2, and a hole diameter D ₆=0.85 mm.

In some embodiments, in order to quickly determine whether the entire device 100 is in tight touch with an endocardial free wall based on actual outflow of the contrast media from the through hole, the sum of the cross-sectional areas of the first through holes 123 on the contact surface 122 of the limiter 120 is set to be greater than or equal to the sum of the cross-sectional areas of the second through holes 114 provided on the side wall of the sleeve 110. The sum of the cross-sectional areas of the first through holes 123 is greater than or equal to the sum of the cross-sectional areas of the second through holes 114 of the sleeve 110 to ensure that in a normal flowing state, the contrast media can preferentially flow out of the first through hole 123 of the limiter 120 after filling the inner cavity of the sleeve 110. When the contrast media is ejected from the first through hole 123 of the contact surface 122 of the limiter 120, the injection assembly 130 does not fit or fully fit the ventricular wall 561; when the contrast media only flows from the second through hole 114 of the sleeve 110 but is not ejected from the first through hole 123 of the limiter 120, the injection assembly 130 fully fits the ventricular wall 561, so that it is possible to determine whether the limiter 120 is in tight touch with the endocardial free wall, i.e., to quickly determine whether the entire device 100 is in tight touch with the endocardial free wall based on actual outflow of the contrast media from the through hole.

In some embodiments, the sleeve 110 may be made of metal or non-metal, such as 304 stainless steel, 316 stainless steel, Nitinol, or PC, and this example selects 316 stainless steel as the material of the sleeve 110.

In some embodiments, referring to Fig. 5, the endocardial injection device 100 further comprises at least one injection tube 210 in communication with the needle tube 132. The injection tube 210 serves to connect the needle hub 131, which allows the drug to enter the needle tube 132. In some embodiments, the injection tube 210 may be a tube made of a PEEK tube, a PI tube, or other polymer materials (e.g., HDPE) which is required to have sealing performance, softness, and certain push performance and bending resistance, and this example selects a PI tube.

In some embodiments, in order to further increase space utilization of the injection tube connecting segment 1313 of the needle hub 131, to determine in advance whether an injection site avoids blood vessels inside the myocardium, and to prevent the injected drug from flowing away from the blood vessel into body circulation and even causing embolization, the injection tube 210 is provided as dual inner cavities in communication with each port on an operation handle 300, i.e., the injection tube 210 comprises two inner cavities provided side by side or coaxially. The newly added passage may serve to inject the contrast media through the needle tube 132 to determine in advance whether the injection site avoids the blood vessels inside the myocardium, under observation of a digital subtraction angiography (DSA) image, if the contrast media disperses or flows away in a certain direction, the needle tube 132 may penetrate into the groove of pectinate muscles or penetrate into a blood vessel, which does not meet conditions for injecting substances such as drugs, and only when the contrast media forms a bulk and beats with a heart 500 under the DSA image, the injection site avoids the blood vessel inside the myocardium, at which time the injection tube 210 may inject the needed drug, thereby avoiding unnecessary injury to the human body.

In some embodiments, referring to Figs. 19 and 20, the injection tube 210 comprises a first passage 211 (for flowing contrast media) and a second passage 212 (for flowing drugs or the like) provided side by side along the axial direction.

In some embodiments, the outer diameter of the injection tube 210 is reduced to half of an inner diameter d ₄ of the injection tube connecting segment 1313, and an outer diameter of the injection tube connecting segment 1313 is D ₄, so that the delivery catheter 200 can accommodate both the first passage 211 and the second passage 212. A gap is formed between the first passage 211 as well as the second passage 212 and the delivery catheter 200 for flowing the contrast media to determine whether the limiter 120 at the distal end of the sleeve 110 is in tight touch with the free wall. The passages provided side by side along the axial direction may achieve dual tube injection, the added first passage 211 may serve to inject a contrast media to determine in advance whether the injection site avoids the blood vessel inside the myocardium, prevent the injected drug from flowing away from the blood vessel into body circulation, and even cause embolization.

In some embodiments, the injection tube 210 may be multi-cavity tubes integrated together side by side in addition to a combination of the two separate tubes to facilitate connecting different syringes for separate injection of multi-component drugs.

In some embodiments, referring to Fig. 21, the injection tube 210 employs an arrangement of coaxial dual cavities, the injection tube 210 comprises the first passage 211 (for flowing contrast media) and the second passage 212 (for flowing drugs or the like) , the first passage 211 and the second passage 212 are coaxially arranged, and the delivery catheter 200 accommodates both the first passage 211 and the second passage 212. The smaller second passage 212 penetrates the first passage 211, and the circumference of the injection tube connecting segment 1313 is provided with at least one fluid hole 1318 which may be a round hole, square hole, or special-shaped hole to communicate the first passage 211 with the needle hub 131 to facilitate flowing and injecting the contrast media. The distal end of the injection tube connecting segment 1313 is connected to the needle hub 131 and cannot cover the fluid hole 1318 when connected to the second passage 212.

Referring to FIG. 1, the present disclosure also discloses an endocardial injection system comprising the operation handle 300, the delivery catheter 200, and the endocardial injection device 100 with a structure described above. The injection tube 210 passes through the delivery catheter 200, the proximal end of the sleeve 110 is fixedly connected to the distal end of the delivery catheter 200, the operation handle 300 drives the injection tube 210 to drive the injection assembly 130 to move axially, so that the injection assembly 130 extends out or retracts into the sleeve 110.

The delivery catheter 200 connected to the sleeve 110 serves to accommodate the injection tube 210, the gap between the injection tube 210 and the delivery catheter 200 serves as a passage for flowing the contrast media. In some embodiments, the delivery catheter 200 has certain softness, push performance, and bending resistance, and may be a tube made of a metal cutting hose, a braided net tube, or other polymeric materials (e.g., HDPE) . A metal braided net tube is selected in this example.

In some embodiments, the proximal end of the operation handle 300 comprises an injection portion 310 in communication with the injection tube 210. The injection portion 310 serves to connect with a syringe, and realize the injection of drug or injection of contrast media along the injection tube 210 via the needle tube 132 into the endocardium. The injection portion 310 is configured to match an injection head of the syringe, ensuring that liquid within the syringe enters the injection tube 210 and reducing the case where liquid leaks outside the operation handle 300.

In some embodiments, the operation handle 300 further comprises a drive portion 320 connected to the proximal end of the injection tube 210, and rotation of the drive portion 310 drives the injection tube 210 and the injection assembly 130 to rotate along the axial direction of the sleeve 110. In some embodiments, the drive portion 320 may be provided as a rotatably operated knob structure that translates the rotation of itself into an axial and spiral combined movement of the injection assembly 130.

In some embodiments, the operation handle 300 is further provided with a connection portion 330 for connecting to the proximal end of the delivery catheter 200 which keeps stationary relative to the operation handle 300 during operation. In some embodiments, the operation handle 300 is further provided with a fluid guide port 340 in communication with the delivery catheter 200, which is provided with a valve body 341 for controlling on-off thereof. In some embodiments, the fluid guide port 340 can be provided on the connection portion 330. The fluid guide port 340 serves to introduce contrast media filled in the inner cavity of the sleeve 110, and the valve body 341 may be used to facilitate controlling on-off of the contrast media. When the delivery catheter 200 filled with the contrast media serves to determine whether the limiter 120 at the distal end of the sleeve 110 is in tight touch with the free wall, the valve body 341 of the fluid guide port 340 on the operation handle 300 is first opened, the contrast media enters through the valve body 341 and then flows within the gap between the injection tube 210 and the delivery catheter 200. Since the guide segment 1312 of the needle hub 131 is provided with four axially symmetric notches 13122 for passing the contrast media, the flowing contrast media fills space of the entire sleeve 110. It is determined with the DSA image whether the limiter 120 at the distal end of the sleeve 110 is in tight touch with the free wall; if the contrast media is ejected from the first through hole 123 on the limiter 120, the device is not in tight touch with the free wall; if the contrast media is ejected from the side hole, i.e., the second through hole 114 on the sleeve 110, the device is in tight touch with the free wall.

The following briefly describes a use process of the endocardial injection device and the endocardial injection system of the present disclosure. Firstly, in order to clearly describe a workflow of the present disclosure, the structure of a heart 500 is now briefly described. Referring to Fig. 22, the heart 500 comprises a right atrium 510, a right ventricle 530, a left atrium 540, and a left ventricle 560, a tricuspid valve 520 of the right ventricle 530 serves to ensure blood circulation from the right atrium 510 to the right ventricle 530. A mitral valve 550 of the left ventricle 560 serves to cause blood to flow from the left ventricle 560 to aorta while the left ventricle 560 contracts, preventing the blood from flowing back to the left atrium 540. An aortic arch 570 rises from the left ventricle 560. In the examples of the present disclosure, the endocardial injection device 100 enters the left ventricle 560 via the aortic arch 570 and then performs injection on the endocardium.

An injection process that the endocardial injection system actually controls the injection depth and determines the correct site on the endocardium in the examples is set forth in detail below by taking the injection of hydrogel 600 into the myocardium as an example:

S1: performing standard femoral puncture, puncturing a guide sheath 400 from a femoral artery into the body to reach the left ventricle 560 via the aortic arch 570, referring to Fig. 22;

S2: inserting the delivery catheter 200 sleeved with an adjustable sheath into the body along the inner cavity of the guide sheath 400 to the left ventricle 560, referring to Fig. 23;

S3: adjusting the distal surface of the endocardial injection device 100 to substantially perpendicular to the free wall of the left ventricle under the aid of the guide sheath 400 and the adjustable sheath, referring to Fig. 24;

S4: advancing the overall endocardial injection device 100 slowly, and determining whether the endocardial injection device 100 abuts the free wall by a motion state of the delivery catheter 200 connected to the sleeve 110 under the guide of angiography or ultrasonography, referring to Fig. 25;

S5: when the endocardial injection device 100 has fit the free wall, opening the valve body 341 of the fluid guide port 340 at the proximal end of the operation handle 300, and flowing contrast media through the delivery catheter 200 surrounding the injection tube 210. Since the guide segment 1312 of the needle hub 131 is provided with four axially symmetric notches 13122 for passing the contrast media, the flowing contrast media fills the entire space of the sleeve 110. It is determined with the DSA image whether the contact surface 122 of the limiter 120 is in tight touch with the free wall, and if the contrast media is ejected from the first through hole 123 on the limiter 120, the device is not in tight touch with free wall; if the contrast media is ejected from the second through hole 114 on the sleeve 110 instead of being ejected from the first through hole 123 on the limiter 120, the device is in tight touch with the free wall, and the next step can be performed, or steps S2 and S3 need to be repeated, until the device is in tight touch with the free wall, referring to Fig. 25;

S6: when it is determined that the device is in tight touch with the free wall, driving the drive portion 320 on the operation handle 300 to cause the needle tube 132 to puncture the free wall, and when the needle hub 131 touches the thrust surface 121 of the limiter 120, the needle tube 132 cannot advance further, thus limiting the injection depth, and preventing the ventricular wall 561 from being pierced, referring to Fig. 26;

S7: injecting an appropriate amount of contrast media into the injection tube 210 again by the injection portion 310 of the operation handle 300, and in the DSA image, if the contrast media disperses or flows away in a certain direction, the needle tube 132 may penetrate into the groove of pectinate muscles or penetrate into the blood vessel, at which time the conditions of injecting the hydrogel 600 is not met, it is necessary to retract the needle tube 132 and repeat the previous operation until the injection conditions are met; in the DSA image, the contrast media forms a bulk and beats with the heart 500, at which time a certain amount of the hydrogel 600 may be injected into the injection tube 210 at one end of the injection portion 310, referring to Fig. 27;

S8: after completing the injection, retracting the needle tube 132 into the sleeve 110, referring to Fig. 28. The above operation is repeated for the second injection site and so on, and until the number of injection sites that meets clinical needs, the devices are withdrawn sequentially to complete the entire injection.

Claims

An endocardial injection device comprising:

a sleeve, the sleeve provided with a limiter at an inside distal end thereof; and

an injection assembly slidably provided within the sleeve, a proximal end of the injection assembly is connected to an injection tube, and a distal end of the injection assembly pierces the limiter, wherein

a proximal end of the limiter comprises a thrust surface in movable abutment with the injection assembly, and a distal end of the limiter is provided with a contact surface; the contact surface is provided with at least one first through hole, an inner wall of the sleeve is provided with at least one second through hole, and the first through hole and the second through hole are in fluid communication.
The endocardial injection device of claim 1, wherein the contact surface of the limiter is provided with a needle hole through which the injection assembly passes, and the thrust surface is provided at a proximal end of the needle hole.
The endocardial injection device of claim 1 or 2, wherein a sum of a cross-sectional area of the first through hole is greater than or equal to a sum of a cross-sectional area of the second through hole.
The endocardial injection device of any one of claims 1 to 3, wherein the injection assembly comprises a needle hub and a needle tube, a distal end of the needle tube is provided with a tip, the needle hub comprises a needle tube connecting segment, a guide segment, and an injection tube connecting segment from the distal end to the proximal end, the needle tube connecting segment is fixed to a proximal end of the needle tube, and the guide segment movably abuts the thrust surface.
The endocardial injection device of claim 4, wherein the guide segment comprises a number of guide portions provided on a periphery of the needle tube, the guide portions extend along an axial direction of the needle tube, and a notch is formed between adjacent guide portions.
The endocardial injection device of claim 4 or 5, wherein the tip of the needle tube comprises a first inclined plane and two second inclined planes symmetrically provided on both sides of the first inclined plane, and the two second inclined planes extend to a distal end to form a puncturing tip.
The endocardial injection device of claim 6, wherein an angle between the puncturing tip and the axial direction of the needle tube ranges from 11°to 30°, an angle between the first inclined plane and the axial direction of the needle tube ranges from 11°to 20°, and an angle between each of the second inclined planes and the axial direction of the needle tube ranges from 11°to 45°.
The endocardial injection device of any one of claims 1 to 7, wherein the injection tube comprises a first passage and a second passage, and the first passage and the second passage are provided side by side or coaxially along the axial direction.
The endocardial injection device of any one of claims 1 to 8, wherein the distal end of the sleeve comprises a limiter mounting segment that is in interference fit with the limiter.
The endocardial injection device of claim 9, wherein the sleeve further comprises a body segment and a delivery catheter connecting segment connected to a proximal end of the limiter mounting segment, and the delivery catheter connecting segment has a size smaller than a size of the body segment.
An endocardial injection system comprising an operation handle, a delivery catheter, and the endocardial injection device of any one of claims 1 to 10, wherein the injection tube passes through the delivery catheter, a proximal end of the sleeve is fixedly connected to a distal end of the delivery catheter, and the operation handle drives the injection tube to drive the injection assembly to move axially, so that the injection assembly extends from or retracts into the sleeve.
The endocardial injection system of claim 11, wherein a proximal end of the operation handle comprises an injection portion in communication with the injection tube.
The endocardial injection system of claim 11 or 12, wherein the operation handle further comprises a drive portion, wherein the drive portion is connected to a proximal end of the injection tube, and rotation of the drive portion drives the injection tube and the injection assembly to spirally move along an axial direction of the sleeve.
The endocardial injection system of any one of claims 11 to 13, wherein the operation handle is further provided with a fluid guide port in communication with the delivery catheter, and the fluid guide port is provided with a valve body for controlling on-off of the fluid guide port.
An endocardial injection method comprising:

puncturing a guide sheath from a femoral artery into a body to reach a left ventricle via an aortic arch;

inserting a delivery catheter sleeved with an adjustable sheath into the body along an inner cavity of the guide sheath to the left ventricle;

adjusting a distal surface of the endocardial injection device of any one of claims 1 to 10 to substantially perpendicular to a free wall of the left ventricle under aid of the guide sheath and the adjustable sheath;

advancing the endocardial injection device slowly, and determining whether the endocardial injection device abuts the free wall by a motion state of the delivery catheter connected to a sleeve under guide of angiography or ultrasonography;

opening a valve body of a fluid guide port at a proximal end of an operation handle, and flowing contrast media through the delivery catheter surrounding an injection tube when the endocardial injection device has fit the free wall;

driving a drive portion on the operation handle to cause a needle tube to puncture the free wall when the device is in tight touch with the free wall;

injecting an appropriate amount of contrast media into the injection tube by an injection portion of the operation handle; and

retracting the needle tube into the sleeve after completing the injection.