CN110812552A - A miniature ventricular assist device with foldable impeller - Google Patents

Abstract

The invention discloses a miniature ventricular auxiliary device with a foldable impeller, comprising a motor and a pump casing. The shaft end of the motor is fixedly connected to a disc, and the disc is connected to one side of the pump casing through a connecting shaft; the side of the pump casing is axially opened with a At the mouth of the manipulator, the inner center of the pump casing is provided with a bearing seat along the axial direction. The bearing seat is provided with a rotating shaft. One end of the rotating shaft is fixed with a bearing, and the other end of the rotating shaft is connected with a spring. , a fixed plate and a rope sleeved on the rotating shaft, the fixed plate is fixed, the two sides of the rope are connected to the impeller, and the impeller is arranged in the impeller groove inside the pump casing; A spring plate is provided; the outer side of the pump casing is provided with three holes for the impeller to pop out; the invention relates to a foldable miniature ventricular auxiliary device of the impeller. The error rate is small.

Description

A miniature ventricular assist device with foldable impeller

technical field

The invention belongs to the field of Class III medical instruments of biomedical engineering, and relates to a miniature ventricular auxiliary device with a foldable impeller.

Background technique

Ventricular assist devices have become a treatment option for patients with severe heart failure and as a bridging therapy for patients awaiting transplant surgery. When the natural heart is partially or completely disabled due to disease and cannot maintain normal circulation throughout the body, ventricular assist devices can temporarily or permanently partially or completely replace the function of the heart and promote blood circulation. Implantability and blood compatibility of the impeller and the device have always been difficult to take into account when this mechanical auxiliary device is used clinically. If the impeller size is small, the motor speed of the device needs to be increased to meet the perfusion requirements, but high speed will inevitably increase the risk of blood cell damage and reduce its blood compatibility. If the impeller is too large, the device can operate at lower rotational speeds, but its implantability is reduced and cannot be implanted by minimally invasive surgery.

The existing foldable impeller artificial heart pump adopts a cage-like structure, such as a foldable minimally invasive implanted intraventricular axial blood pump designed by CN201410450242.0, which can contract its own pump shell when the heart pump is implanted. The purpose of the fold, but also has a drawback when the heart pump is taken out. Since the secondary shrinkage structure is not designed, it is difficult to take out. The present invention provides a miniature ventricular assist device and method with a foldable impeller, which includes a secondary folding structure, which can not only achieve the purpose of achieving the impeller contraction during implantation, but also realize the impeller when the ventricular assist device is taken out after use. contraction, so as to achieve the purpose of minimally invasive surgery.

SUMMARY OF THE INVENTION

In order to realize the ventricular assist device implanted by the minimally invasive technology, while meeting the required hydraulic performance, reduce the motor speed of the device and improve the blood compatibility, the present invention proposes a miniature ventricular assist device with a foldable impeller.

The technical solution adopted by the present invention to solve the technical problem is: a foldable impeller is designed on the basis of the original heart pump. That is to say, the diameter of the impeller is large, and it can achieve the hydraulic performance of cardiac assistance under the condition of low speed, such as no more than 10,000 revolutions per minute. The reduction of the speed reduces the shear stress on the edge of the blood pump blade and reduces the damage to blood cells. small, thus improving the blood compatibility of the blood pump. While meeting the required hydraulic performance, the speed of the blood pump is reduced, and the blood compatibility of the blood pump is improved.

The specific implementation structure is as follows: a miniature ventricular auxiliary device with a foldable impeller, comprising a motor (1) and a pump casing (6), the shaft end of the motor (1) is fixedly connected to a disk, and the disk passes through the connecting shaft (7) One side of the pump casing (6) is connected; the side of the pump casing (6) is axially opened with a mechanical arm port (8), and the mechanical arm port (8) is axially opposite to the inner pump casing (6) with a rotating A shaft (17), one end of the rotating shaft (17) is fixed with a bearing, and the other end of the rotating shaft (17) is connected with a spring (20). 4) and the rope (12) sleeved on the rotating shaft (17), the fixed plate (4) is fixed, and the two sides of the rope (12) are connected to the impeller (5), and the impeller (5) is located at the Inside the impeller groove (11) inside the pump casing (6); the impeller groove (11) is also provided with a spring sheet (3) along the radial direction; the outer side of the pump casing (6) is provided with three supply impellers (5) along the circumference The ejected hole; in the absence of external force of the mechanical arm, the impeller (5) will be ejected through the hole of the pump casing (6) under the action of the spring plate (3); when the impeller (5) needs to be retracted into the impeller groove ( 11), the mechanical arm penetrates into one end of the rotating shaft (17) through the mechanical arm port (8), and the mechanical arm rotates one end of the rotating shaft (17), which can drive the rope (12) to wrap around the rotating shaft (17). and drive the impeller (5) to be completely retracted into the impeller groove (11), and then the mechanical arm pushes the rotating shaft (17) in the axial direction, thereby driving the gear (13) to slide to the fixed plate (4), and finally embedded in the The fixing of the impeller (5) in the impeller groove (11) is realized in the concave-shaped clamping block (14) of the fixing plate (4).

Further, the rotating shaft (17) can be fixed by a cylindrical bearing seat provided on the inner side of the pump casing (6) along the axial direction, and the two ends of the bearing seat are connected with the pump casing (6) by welding; the pump casing (6) is coated with biological Compatible coating and having anti-coagulation channel (9), the anti-coagulation channel (9) is located inside the impeller groove (11), which can be realized by the channel in the radial direction opened on the bearing seat, and the anti-coagulation channel (9) is located inside the impeller groove (11). One end of the channel (9) is communicated with the impeller groove (11), and the other end of the anticoagulation channel (9) can be administered externally.

Further, the two sides of the impellers (5) and the rope connection are punched symmetrically to realize the connection of the rope (12) and the impeller (5), and the rope (12) can pass through the anticoagulation channel (9) and be connected to the rotating shaft. (17).

Further, when the mechanical arm pushes the rotating shaft (17) in the axial direction, the spring (20) at the other end of the rotating shaft (17) will be compressed, and when the axial thrust of the mechanical arm is removed, the spring (20) will push the rotation The shaft (17) is restored.

Further, the manipulator port (8) is provided with a top slot (18) that can be used to control the rotating shaft by the manipulator, and the top slot (18) can be jammed by the manipulator. After turning, the rotating shaft (17) is locked and fixed by the top slot (18).

Further, the outer ring of the fixed disk (4) is fixed on the bearing seat, and a center ball bearing (19) of the fixed disk is arranged between the inner ring of the fixed disk (4) and the rotating shaft (17). When moving or rotating, the fixed plate does not follow the action of the rotating shaft (17); the fixed plate (4) is surrounded by three concave-shaped clamping blocks (14), and each concave-shaped clamping block (14) has two protrusions (15), there is a magnet at the bottom of the protrusion (15), the gear (13) has three gear teeth (16) with magnets, the fixing plate (4) and the gear (13) cooperate to complete the pairing of the rope (12) Retraction restrictions.

Further, the motor (1) is fixed in the motor casing, the motor casing is provided with a through hole on the side close to the pump casing (6), the ball bearing (10) is embedded in the through hole, and the inner ring of the ball bearing (10) is embedded with a disc , the disc is connected with the motor shaft, and the side of the disc close to the pump casing (6) is welded with four connecting shafts (7) evenly distributed along the circumference. The connecting shaft (7) is fixedly connected to the pump casing (6), and the rotation of the motor shaft It can drive the rotation of the pump casing (6).

Further, the impeller groove (11) is coated with a biocompatible coating, and the bottom is provided with a spring sheet (3), which can make the impeller (5) pop out when the heart pump implantation operation is performed.

Further, the impeller (5) is coated with a biocompatible material.

In this device, the relationship between the pump head and the impeller diameter is: H=(U ₂ *V _u2 -U ₁ V _u1 )/g, which can be simplified as H=U2*U2/2g, U ₂ =π*D2*n /60, D ₂ is the outer diameter of the impeller, and n is the rotational speed. The impeller diameter of the pump in this product is twice the diameter of the original impeller after expansion, so the lift performance can reach four times that of the original impeller. And the outer diameter of the impeller increases, which can reduce the rotational speed in actual use, which not only keeps the power stable without affecting the flow and head of the pump, but also reduces the required rotational speed of the impeller of the pump, thereby causing the heart pump to destroy blood cells. decrease.

The heart pump includes an impeller, a pump casing, and a motor. The impeller includes an impeller shaft and a foldable foldable blade arranged on the impeller shaft. One end of the folded pump casing with a blood pump inlet is connected to the outer casing of the motor. Fold the inside of the pump casing. The impeller is retracted in the pump when not in use, and the bottom of the impeller is supported by a spring sheet, the spring sheet is in a retracted state, and a rope is radially linked to the rotating shaft at the bottom of the impeller. The outer casing of the pump has a sleeve that wraps the impeller to shrink it. The pump is sent into the human heart through minimally invasive surgery, and the mantle is pulled out. At this time, the spring leaf at the bottom of the impeller returns to its shape, and the impeller is ejected to reach the impeller length required for normal heart pump operation. normal work in the heart. When the heart pump has finished its work and is about to be taken out, the impeller can be re-contracted by rotating the rotating shaft, so that the heart pump can be taken out again through minimally invasive surgery without causing secondary damage.

Compared with the prior art and method, the present invention has the following advantages:

1. The present invention relates to a miniature ventricular assist device and method with a foldable impeller. The folded blade is a rigid blade with a mechanical structure, which is easy to manufacture, has a simple mechanical structure, and has a small error rate in use.

2. The present invention relates to a miniature ventricular auxiliary device and method with a foldable impeller. During implantation, the folded impeller can be folded, which reduces the volume of the minimally invasive implantation, thereby reducing the surgical risk and reducing the pain of the patient.

3. The present invention relates to a miniature ventricular auxiliary device and method with a foldable impeller. The folded impeller is unfolded after being implanted in the heart, which can achieve the requirement of pumping blood without destroying blood cells.

4. The present invention relates to a miniature ventricular assist device and method with a foldable impeller. The folded pump casing is coated with a layer of blood-compatible flexible material, and the surface of this structure and composition interacts with the physiological environment and will not adsorb and interact. Deposition of protein will not trigger platelet activation, lead to coagulation and other adverse reactions, and has good blood compatibility.

5. The present invention relates to a miniature ventricular assist device and method with a foldable impeller, which can be minimally invasively entered into the left ventricle through a small incision in the chest and implanted in the position of the aortic valve. situation to assist other relevant positions of the heart.

6. The present invention relates to a miniature ventricular assist device and method with a foldable impeller, which is provided with an anticoagulant delivery channel, which can be used to inject anticoagulant during the operation of the heart pump to prevent the generation of thrombus in the heart pump, and at the same time, it can be Medications such as saline are injected to prevent the heart pump from overheating.

7. The present invention relates to a miniature ventricular assist device and method with a foldable impeller, which can be retracted and taken out after use, so that the purpose of minimally invasive surgery can also be achieved when taking out.

Description of drawings

1 is a schematic cross-sectional view of the overall structure of a miniature ventricular assist device with a foldable impeller of the present invention.

Figure 2 is a left side view of the overall structure of a miniature ventricular assist device with a foldable impeller of the present invention.

Fig. 3 is a schematic diagram of the contracting structure of a miniature ventricular assist device with a foldable impeller of the present invention.

FIG. 4 is a schematic structural diagram of a concave block of a miniature ventricular assist device with a foldable impeller of the present invention.

Fig. 5 is a working flow chart of the specific implementation of a miniature ventricular assist device with foldable impeller of the present invention.

In the figure, 1. Motor; 3. Leaf spring; 4. Fixed plate; 5. Impeller; 6. Pump casing; 7. Connecting shaft; . Impeller groove; 12. Rope; 13. Gear; 14. Concave block; 15. Protrusion; 16. Gear tooth; 17. Rotating shaft; 18. Top slot; 19. Fixed disc center ball bearing; 20. Spring.

Detailed ways

1 and 2, FIG. 1 is a schematic cross-sectional view of the overall structure of a miniature ventricular assist device with a foldable impeller of the present invention, and FIG. 2 is a left view of the overall structure of a miniature ventricular assist device with a foldable impeller of the present invention. The device comprises a motor (1) and a pump casing (6), the shaft end of the motor (1) is fixedly connected to a disc, and the disc is connected to one side of the pump casing (6) through a connecting shaft (7); A manipulator port (8) is opened in the side axial direction, and a rotating shaft (17) is arranged inside the pump casing (6) which is axially opposite to the manipulator port (8), and one end of the rotating shaft (17) is fixed with a bearing, The other end of the rotating shaft (17) is connected with the spring (20), and the rotating shaft (17) is sleeved with a gear (13), a fixed disk (4) and a rope (12) sleeved on the rotating shaft (17) in turn in the axial direction. ), the fixed plate (4) is fixed, the two sides of the rope (12) are connected to the impeller (5), and the impeller (5) is arranged in the impeller groove (11) inside the pump casing (6); The impeller groove (11) is also provided with a spring sheet (3) along the radial direction; the outer side of the pump casing (6) is provided with three holes for the impeller (5) to eject; (5) will be ejected through the holes of the pump casing (6) under the action of the spring plate (3); when the impeller (5) needs to be retracted into the impeller groove (11), the mechanical arm will penetrate deep through the mechanical arm port (8) To one end of the rotating shaft (17), rotating one end of the rotating shaft (17) by the mechanical arm can drive the rope (12) to wrap around the rotating shaft (17), and drive the impeller (5) to fully retract into the impeller groove ( 11), and then the mechanical arm pushes the rotating shaft (17) in the axial direction, thereby driving the gear (13) to slide to the fixed plate (4), and finally embedded in the concave block (14) of the fixed plate (4). , to realize the fixation of the impeller (5) in the impeller groove (11).

The above-mentioned motor 1 adopts a brushless DC motor, which is composed of a motor stator and a motor rotor, which provides power for the rotation of the folding blood pump. The mechanical arm port 8 is an opening that allows the mechanical arm to pass through. The connecting shaft 7 provides power for the rotation of the pump casing 6 . The pump casing 6 is a cylindrical structure made of metal, and a layer of flexible material is adhered to the outside. The flexible material is made of polyurethane material to improve blood compatibility. The inside is coated with a layer of polyurethane to improve the sealing of the blood pump. The center of the pump casing 6 is hollow, with an impeller groove 11 in the middle, and an anticoagulant channel 9 is opened in the bearing seat inside the pump casing 6 along the radial direction. The impeller 5 is contracted in the impeller groove 11 on the pump casing 6, and the impeller groove 11 is provided with a small protrusion to prevent the impeller 5 from flying out. The bottom of the impeller groove 11 is stuck with a spring plate 3, and the spring plate 3 is coated with a biocompatible material.

As shown in Fig. 1-2, as a specific embodiment of the present invention, the above-mentioned rotating shaft (17) can be fixed by a cylindrical bearing seat provided in the inner side of the pump casing (6) along the axial direction, and the two ends of the bearing seat are connected to the pump casing (6) Connected by welding; the pump casing (6) is coated with a biocompatible coating and has an anticoagulation channel (9), which is located inside the impeller groove (11), which can be opened by opening the bearing seat. One end of the anticoagulation channel (9) is communicated with the impeller groove (11), and the other end of the anticoagulation channel (9) can be administered externally.

As a specific embodiment of the present invention, the above-mentioned two sides of the impeller (5) and the rope connection are punched symmetrically to realize the connection of the rope (12) and the impeller (5). ) through and is connected to the rotating shaft (17).

As a specific embodiment of the present invention, when the mechanical arm pushes the rotating shaft (17) in the axial direction, the spring (20) at the other end of the rotating shaft (17) will be compressed. The spring (20) will push the rotating shaft (17) back to its original position.

As a specific embodiment of the present invention, the above-mentioned manipulator port (8) is provided with a top slot (18) that can be used to control the rotating shaft by the manipulator, and the top slot (18) can be jammed by the manipulator. After the arm completes the rotation of the rotating shaft (17), the rotating shaft (17) is clamped and fixed by the locking groove (18) at the top.

As a specific embodiment of the present invention, the above-mentioned motor (1) is fixed in a motor casing, a through hole is formed on the side of the motor casing close to the pump casing (6), the ball bearing (10) is embedded in the through hole, and the ball bearing ( 10) A disc is embedded in the inner ring, and the disc is connected with the motor shaft. The side of the disc close to the pump casing (6) is welded with four connecting shafts (7) evenly distributed along the circumference, and the connecting shaft (7) is fixedly connected to the pump casing. (6), the rotation of the motor shaft can drive the rotation of the pump casing (6).

As a specific embodiment of the present invention, the above-mentioned impeller groove (11) is coated with a biocompatible coating, and the bottom is provided with a spring sheet (3), during the heart pump implantation operation, the spring sheet (3) can be Pop the impeller (5) out.

As shown in Figures 3-4, as a specific embodiment of the present invention, the outer ring of the fixed disk (4) is fixed on the bearing seat, and the center ball of the fixed disk is provided between the inner ring of the fixed disk (4) and the rotating shaft (17). The bearing (19), when the rotating shaft (17) moves axially or rotates, the fixed plate does not follow the action of the rotating shaft (17); the fixed plate (4) is surrounded by three concave blocks (14), each concave There are two protrusions (15) on the type clamping block (14), the bottom of the protrusions (15) has magnets, the gear (13) has three gear teeth (16), and there are magnets, the fixed plate ( 4) Cooperate with the gear (13) to complete the retraction restriction of the rope (12).

1 , 2 , 3 , 4 , and 5 , FIG. 5 is a working flow chart of the specific implementation of a miniature ventricular assist device with a foldable impeller of the present invention. A miniature ventricular assist device with a foldable impeller of the present invention is implanted through a chest incision, and the pump casing 6 is wrapped by a mantle. After implanting the ventricle, the mantle is removed, and the impeller 5 can be expanded due to the contracted spring sheet 3 at the bottom of the impeller 5, and the impeller 5 works to pump blood. In order to prevent blood from entering the heart pump to form thrombus and block the heart pump during working state, anticoagulant and normal saline can be delivered through the anticoagulant delivery channel 9 to avoid thrombosis, and the working temperature of the heart pump can be appropriately lowered. After the work is completed, use the mechanical arm to enter the mechanical arm port 8, and the mechanical arm is stuck into the slot 18 at the top of the rotating shaft. At this time, rotating the mechanical arm can make the rotating shaft 17 rotate so that the rope 12 is wound on the rotating shaft 17, and drives the impeller. 5 retracts back to the impeller groove 11, at this time the bottom spring plate 3 of the impeller 5 is compressed. Then push the mechanical arm along the ① direction in FIG. 3 to the ② direction. At this time, the bottom spring plate 3 of the rotating shaft 17 is compressed, and the gear teeth 16 are clamped into the two protrusions 15 of the concave block 14 on the fixed plate 4 . The bottom of the protrusion 15 and the gear teeth 13 are provided with magnets. At this time, the bottom spring sheet 3 of the impeller 5 and the bottom spring sheet of the rotating shaft 17 contract, so that the impeller 5 rebounds. However, due to the blocking of the concave block 14 and the protrusion 15 and the fixing of the magnet, the impeller 5 cannot rebound, and the shrinking process of the impeller 5 is completed. The ventricular assist device is then removed and the surgery is completed.

In the description of this specification, reference to the terms "one embodiment," "some embodiments," "exemplary embodiment," "example," "specific example," or "some examples", etc., is meant to incorporate the embodiments A particular feature, structure, material, or characteristic described by an example or example is included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

Although embodiments of the present invention have been shown and described, it will be understood by those of ordinary skill in the art that various changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, The scope of the invention is defined by the claims and their equivalents.

Claims (9)

1. A mini-type ventricle auxiliary device with a foldable impeller is characterized by comprising a motor (1) and a pump shell (6),

the shaft end of the motor (1) is fixedly connected with a disc, and the disc is connected with one side of the pump shell (6) through a connecting shaft (7); a mechanical arm opening (8) is axially formed in the side of the pump shell (6), the mechanical arm opening (8) axially faces a rotating shaft (17) arranged in the pump shell (6), one end of the rotating shaft (17) is fixed through a bearing, the other end of the rotating shaft (17) is connected with a spring (20), the rotating shaft (17) is sequentially sleeved with a gear (13), a fixed disc (4) and a rope (12) sleeved on the rotating shaft (17) along the axial direction, the fixed disc (4) is fixed, two sides of the rope (12) are connected with impellers (5), and the impellers (5) are arranged in impeller grooves (11) in the pump shell (6); a spring piece (3) is also arranged in the impeller groove (11) along the radial direction; the outer side of the pump shell (6) is provided with three holes for the impeller (5) to pop up along the circumference;

under the condition that no mechanical arm external force is applied, the impeller (5) can be ejected out through the hole of the pump shell (6) under the action of the spring piece (3); when impeller (5) need be withdrawed impeller recess (11) in, the arm is deepened the one end of rotation axis (17) through arm mouth (8), the one end of this rotation axis (17) is rotatory through the arm, can drive rope (12) winding on rotation axis (17), and drive impeller (5) and withdraw impeller recess (11) completely in, then the arm promotes rotation axis (17) along the axial, and then drive gear (13) and slide to fixed disk (4), and finally inlay in concave type fixture block (14) of fixed disk (4), realize the fixed of impeller (5) in impeller recess (11).

2. A mini ventricular assist device with a foldable impeller according to claim 1, wherein the rotating shaft (17) can be fixed by a cylindrical bearing seat axially arranged inside the pump casing (6), and two ends of the bearing seat are connected with the pump casing (6) by welding; the pump shell (6) is coated with a biocompatible coating and is provided with an anticoagulation channel (9), the anticoagulation channel (9) is positioned on the inner side of the impeller groove (11) and can be realized through a channel in the radial direction formed on the bearing seat, one end of the anticoagulation channel (9) is communicated with the impeller groove (11), and the other end of the anticoagulation channel (9) can be dosed from the outside.

3. A mini ventricular assist device with foldable impeller according to claim 2, wherein the connection between the impeller (5) and the rope is symmetrically perforated to realize the fastening between the rope (12) and the impeller (5), and the rope (12) can pass through the anticoagulation channel (9) and is connected to the rotation shaft (17).

4. A miniature ventricular assist device with foldable impeller according to claim 1, wherein when the mechanical arm pushes the rotary shaft (17) in the axial direction, the spring (20) at the other end of the rotary shaft (17) will be compressed, and when the pushing force of the mechanical arm in the axial direction is removed, the spring (20) will push the rotary shaft (17) to restore.

5. A mini ventricular assist device with foldable impeller according to claim 1, wherein the mechanical arm port (8) is provided with a top end slot (18) for operating the rotation shaft by using the mechanical arm, the top end slot (18) can be blocked by the mechanical arm, and the rotation shaft (17) is blocked and fixed by the top end slot (18) after the mechanical arm completes the rotation of the rotation shaft (17).

6. A mini ventricular assist device with foldable impeller according to claim 1, wherein the outer ring of the fixed disk (4) is fixed on the bearing seat, a fixed disk center ball bearing (19) is arranged between the inner ring of the fixed disk (4) and the rotating shaft (17), and the fixed disk does not follow the rotating shaft (17) when the rotating shaft (17) moves axially or rotates; there are three concave type fixture block (14) around fixed disk (4), have two archs (15) on every concave type fixture block (14), there is magnet protruding (15) bottom, there are three teeth of a cogwheel (16) on gear (13), and have magnet, fixed disk (4) and gear (13) cooperate and accomplish the restriction of receiving and releasing to rope (12).

7. The mini ventricular assist device with the foldable impeller as claimed in claim 1, wherein the motor (1) is fixed in a motor box, a through hole is formed in one side of the motor box close to the pump housing (6), the ball bearing (10) is embedded in the through hole, a disc is embedded in an inner ring of the ball bearing (10), the disc is connected with a motor shaft, four connecting shafts (7) are uniformly welded along the circumference on one side of the disc close to the pump housing (6), the connecting shafts (7) are fixedly connected with the pump housing (6), and the rotation of the motor shaft can drive the pump housing (6) to rotate.

8. A collapsible mini-ventricular assist device according to claim 1, wherein the impeller recess (11) is coated with a biocompatible coating and the bottom is provided with a leaf spring (3), and the leaf spring (3) can make the impeller (5) pop up when performing the heart pump implantation procedure.

9. A foldable impeller mini-ventricular assist device according to claim 1, wherein the impeller (5) is coated with a biocompatible material.

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