An artificial heart pump impeller structure

Abstract

The present invention provides an artificial heart pump impeller structure, the impeller structure includes 2 groups of centrifugal pump blades, 2 centrifugal pump upper cover plates, 2 guide cones, and a corresponding shell, which includes an external shell, 1 to 2 groups of guide vanes and 1 to 2 guide cones, thereby forming a special structure of the present invention, which can realize the miniaturization of the artificial heart pump and optimize the blood compatibility. The present invention adopts a multi-stage centrifugal pump structure with a small appearance and good blood compatibility to construct a simple and compact artificial heart pump structure. The structure adopts multiple centrifugal pump blades connected in series, which can achieve more efficient blood pumping in a more compact space. At the same time, the addition of a guide cone structure can effectively improve the flow field structure of the heart pump and achieve a good transition of the flow fields of each centrifugal pump, thereby improving blood compatibility.

Description

Technical Field

[0001] The invention belongs to the technical field of medical equipment, and in particular relates to an artificial heart pump impeller structure. Background Art

[0002] Heart failure, also known as HF, refers to a group of clinical syndromes in which the venous return blood cannot be fully pumped out of the heart due to myocardial dysfunction. Heart failure is mostly caused by various cardiovascular diseases and is the terminal stage of heart disease development. The mortality rate and readmission rate are extremely high. The three-year readmission rate is higher than 50%, the five-year mortality rate is as high as 50%, and the ten-year mortality rate is as high as 90%, which is equivalent to malignant tumors or advanced cancer. It is considered to be "the fortress that has not yet been conquered in the cardiovascular field." According to global epidemiological surveys, on average, 3 to 5 people in every 100 people in the world suffer from heart failure to varying degrees. At the same time, 1 in every 5 people will experience heart failure to varying degrees at a certain age. With the rapid aggravation of the aging population problem worldwide, the number of people with heart failure will show a serious upward trend. In addition, due to life pressure and health problems, the number of patients with heart failure shows a worrying trend of younger age. In countries with advanced medical technology, the treatment level of acute cardiovascular diseases is high, but most of them cannot be cured and will bring many potential problems, thus inducing heart failure. Therefore, even in countries with highly developed medical technology, heart failure is still an extremely troubling medical problem.

[0003] On the other hand, there is an urgent need to develop technical means for the treatment of heart failure. Heart transplantation, the most effective traditional treatment option, is not universal due to the severe shortage of suitable heart donors. Most patients die before they can find a suitable match. As for drug treatment, there are currently no reports on the use of drug treatment to cure heart failure, and the effectiveness is poor. Therefore, neither heart transplantation nor drug treatment is suitable as a universal treatment for heart failure. With the development of artificial materials and biomechanical technology, artificial hearts are expected to become the most effective and reliable treatment for many heart failure patients.

[0004] An artificial heart is a mechanical device made of biomaterials that temporarily or permanently replaces the human heart to achieve the pumping function for patients with heart failure. Artificial hearts cover a wide range, with artificial heart pumps being the most important. They have the advantages of compact structure, reliable operation, and no need to remove the patient's own heart. In addition to being directly implanted in the human heart, they are also a key part of the extracorporeal membrane oxygenation (ECMO) system, which plays an important role in the treatment of the COVID-19 epidemic.

[0005] In the field of artificial heart pumps, there are mainly two types: centrifugal pumps and axial flow pumps, each with its own advantages and disadvantages. Due to the excellent properties of centrifugal pumps, the third generation of artificial heart pumps are almost all centrifugal pumps, but single-stage centrifugal pumps have low efficiency, large speed and volume. At present, in order to reduce surgical wounds and improve the quality of life of patients, miniaturization, lightweight and high biocompatibility are the research focuses in this field. Among them, optimizing the blood pumping efficiency and blood compatibility of heart pumps through special structural design is a major trend. Summary of the invention

[0006] In view of the shortcomings of the prior art, the object of the present invention is to provide an artificial heart pump impeller structure, which adopts the following technical solutions:

[0007] An artificial heart pump impeller structure comprises two groups of centrifugal pump blades, two centrifugal pump upper cover plates and two centrifugal pump guide cones; a corresponding shell is arranged outside the impeller structure, and the shell comprises an outer shell body, 1 to 2 groups of guide vanes and 1 to 2 guide cones of the guide vanes; the centrifugal pump blades, the centrifugal pump upper cover plates and the centrifugal pump guide cones are combined into an inseparable integral impeller, or are mutually fixed to form an integral impeller through a key or pin structure through a central axis; 1 to 2 groups of guide vanes and 1 to 2 groups of guide cones of the guide vanes are fixed inside the shell; the centrifugal pump blades and the guide vanes appear alternately from the inlet to the outlet, and the centrifugal pump blades are closer to the inlet side.

[0008] Furthermore, a certain gap is left between the guide vane fixed on the casing and the guide cone of the guide vane and the impeller to prevent the impeller from colliding with the casing when rotating.

[0009] Furthermore, the outer side surface of the centrifugal pump guide cone is specially designed to achieve a good transition of each stage of the centrifugal pump and optimize blood compatibility;

[0010] The special design of the outer side of the guide cone is that the inlet, each stage of centrifugal pump blades and each stage of guide vanes are equipped with separate guide cones, and the guide cones are concave, straight, protruding or a combination of the three.

[0011] Further, the number of blades and guide vanes of the centrifugal pump is fixed, and the number of blades and guide vanes of the centrifugal pump is equal or unequal;

[0012] The number of blades of the centrifugal pump is 2 to 8.

[0013] Furthermore, the centrifugal pump blade and the adjacent guide vane have opposite rotation directions in a top view.

[0014] Compared with the prior art, the present invention has the following beneficial effects:

[0015] (1) The impeller of the artificial heart pump of the present invention is combined with the corresponding housing to form a complete flow-through portion of the artificial heart pump, i.e., the main portion of the heart pump that contacts the blood. This portion has a decisive influence on the blood compatibility and volume of the artificial heart pump. The special structure of the present invention improves the blood pumping efficiency of the artificial heart pump, thereby achieving high-efficiency blood pumping in a smaller volume. At the same time, it has good blood compatibility and a lower probability of hemolysis and thrombosis.

[0016] (2) When two groups of centrifugal pump blades, the centrifugal pump front cover plate and the guide cone form an inseparable whole, the guide cone can be a hollow structure as the central axis. Compared with the solid impeller shaft, the hollow structure uses less shaft material of the same strength, which is helpful for the lightweight of the impeller.

[0017] (3) The artificial heart pump of the present invention has a compact and reasonable structure, and has a small number of simple components. Since the inlet and outlet of the artificial heart pump are connected to a soft catheter, the use of a two-stage centrifugal pump will not significantly increase the height of the traditional centrifugal artificial heart pump. On the contrary, it will reduce the outer diameter of the traditional centrifugal artificial heart pump due to the improvement of blood pumping efficiency, and the outer diameter of the artificial heart pump is the largest factor affecting the appearance and volume of the artificial heart pump;

[0018] (4) In addition to the special design of the impeller geometry and the housing, the main working principle of the heart pump of the present invention is almost the same as that of the common centrifugal artificial heart pump. The control strategy, design method, optimization method, etc. of the common centrifugal artificial heart pump (such as periodically adjusting the impeller speed to achieve pulsatile blood pumping, etc.) can also be applied to the present invention, which has good portability and universality.

[0019] (5) The blades and guide vanes at each level of the present invention are all equipped with guide cones, which can achieve effective and smooth transition of the flow field of each level of the centrifugal pump, and can also optimize the flow field structure of the artificial heart pump and improve biocompatibility;

[0020] (6) The present invention specially combines two sets of centrifugal pumps and guide cones connected in series to construct a simple and compact artificial heart pump structure, which can achieve more efficient blood pumping in a more compact space. At the same time, the addition of the guide cone structure can effectively improve the flow field structure of the heart pump and achieve a good transition of the flow fields of the centrifugal pumps at all levels. In addition, according to the same method of the present invention, more than two sets of centrifugal pumps can be connected in series. The specific number of series connections is determined according to the patient's physical condition and the placement of the artificial heart pump. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 1 / 2 longitudinal cross-sectional view of the artificial heart pump impeller structure of Example 1 of the present invention;

[0022] Figure 2FIG. 1 is a structural diagram of the internal part of the artificial heart pump impeller structure of Example 1 of the present invention;

[0023] Figure 3 This is an overall appearance diagram of the artificial heart pump according to Embodiment 1 of the present invention;

[0024] Figure 4 FIG. 2 is a structural diagram of the internal part of the artificial heart pump impeller structure of Embodiment 2 of the present invention;

[0025] Figure 5 This is an overall appearance diagram of an artificial heart pump according to Embodiment 2 of the present invention;

[0026] Figure 6 A top view of a portion of the structure of an artificial heart pump impeller structure according to Embodiment 3 of the present invention;

[0027] Figure 7 Schematic diagram of the second-stage guide vane B of the artificial heart pump impeller structure of Example 3 of the present invention.

[0028] Among them, 1-inlet; 2-first-stage centrifugal pump upper cover plate; 3-first-stage centrifugal pump blades; 4-first-stage centrifugal pump guide cone; 5-first-stage guide vane; 6-second-stage centrifugal pump upper cover plate; 7-second-stage centrifugal pump blades; 8-second-stage centrifugal pump guide cone; 9-second-stage guide vane A; 10-outlet; 11-outer casing; 12-guide cone of second-stage guide vane A; 13-guide cone of first-stage guide vane; 14-second-stage guide vane B. DETAILED DESCRIPTION

[0029] It should be understood that, in the description of the present invention, the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first", "second", etc. are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0030] It should be noted that in the description of the present invention, unless otherwise clearly specified and limited, the terms "disposed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood by specific circumstances.

[0031] Those skilled in the art should understand that the present invention necessarily includes necessary pipelines, conventional valves and general pump equipment for realizing a complete process, but the above content does not belong to the main inventive point of the present invention. Those skilled in the art can add layouts on their own based on the process flow and equipment structure selection, and the present invention does not make special requirements and specific limitations on this.

[0032] The technical solution of the present invention is further described below with reference to the accompanying drawings and through specific implementation methods.

[0033] Example 1

[0034] This embodiment provides an artificial heart pump impeller structure, such as Figure 1-3 As shown, the impeller structure includes a first-stage centrifugal pump upper cover plate 2, first-stage centrifugal pump blades 3, first-stage centrifugal pump guide cone 4, second-stage centrifugal pump upper cover plate 6, second-stage centrifugal pump blades 7, second-stage centrifugal pump guide cone 8 and an outer shell. Among them, the bottom surface of the first-stage centrifugal pump guide cone 4 and the second-stage centrifugal pump guide cone 8 also serves as the lower cover plate of each stage of the impeller. In addition to the outer shell 11, the outer shell also includes the first-stage guide vane 5, the second-stage guide vane A 9, the guide cone 12 of the second-stage guide vane A and the guide cone 13 of the first-stage guide vane fixed thereon. The outer shell is divided into two parts, the left outer shell and the right outer shell can be combined to form an internal chamber, an inlet 1 and an outlet 10. The overall appearance of the artificial heart pump is as follows Figure 3 shown.

[0035] The outlets of the two-stage impellers of this embodiment both have a certain inclination angle. The first-stage centrifugal pump impeller is composed of the first-stage centrifugal pump upper cover plate 2, the first-stage centrifugal pump blades 3 and the first-stage centrifugal pump guide cone 4, and the inclination angle of its outlet is 25.7°. The second-stage centrifugal pump impeller is composed of the second-stage centrifugal pump upper cover plate 6, the second-stage centrifugal pump blades 7 and the second-stage centrifugal pump guide cone 8, and the inclination angle of its outlet is 13.1°. The second-stage centrifugal pump impeller is the main impeller with an outlet diameter of 25mm, and the first-stage centrifugal pump impeller is the auxiliary impeller with an outlet diameter of 12mm.

[0036] Blood flows in from the inlet 1 of the pump body, passes through the blunt tip of the first-stage centrifugal pump guide cone 4 and is guided to the first-stage centrifugal pump blade 3. The blood is accelerated by the centrifugal force of the impeller to obtain kinetic energy, then flows into the first-stage guide vane 5, where the kinetic energy is converted into pressure energy, then flows into the second-stage centrifugal pump blade 7 to obtain kinetic energy, and finally passes through the second-stage guide vane A 9, where the obtained kinetic energy is converted into pressure energy and flows out through the outlet 10.

[0037] The first-stage centrifugal pump blades 3, the second-stage centrifugal pump blades 7, the first-stage centrifugal pump upper cover plate 2, the second-stage centrifugal pump upper cover plate 6, the first-stage centrifugal pump guide cone 4 and the second-stage centrifugal pump guide cone 8 can be combined into an inseparable impeller, or can be fixed to each other through the central axis through structures such as keys and pins to form an integral impeller.

[0038] Example 2

[0039] This embodiment provides a second artificial heart pump impeller structure, such as Figure 4-5 As shown, compared with Example 1, the outlet of the second-stage centrifugal pump blade 7 is not inclined, and it does not have the second-stage guide vane A 9 and the guide cone 12 of the second-stage guide vane A, and the outer shell is adjusted. The outer shell of this Example 2 is still divided into two parts, the left and right parts, which are combined to form an internal chamber and an inlet 1. The outlet 10 is located on the right half of the outer shell. The upper half of the outer shell is the same as Example 1, which is approximately a straight cylinder, and the lower half is a volute structure, which serves as a kinetic energy conversion device for the last stage impeller. The internal structure of this embodiment is as shown in FIG. Figure 4 As shown, the overall appearance is Figure 5 shown.

[0040] In this embodiment, blood flows into the pump body from the inlet 1, and the first half of the blood flow is the same as that in Embodiment 1, except that after flowing through the second-stage impeller, the blood flows directly into the vortex chamber in the form of a volute, and the vortex chamber part realizes the conversion of kinetic energy into pressure energy, and finally flows out from the outlet 10.

[0041] Example 3

[0042] like Figure 6-7 As shown, compared with Example 2, this embodiment only adds a second-stage guide vane B14 to the outer ring of the second-stage centrifugal pump impeller. The second-stage guide vane B14 is fixed to the housing. The appearance of the second-stage guide vane B14 is as shown in FIG. Figure 7 As shown, two types of guide vanes, open and closed, can be used. In the figure, the lower cover plate of the second-stage guide vane B14 is a part of the outer shell.

[0043] The blood flow condition of this embodiment is similar to that of Embodiment 2, except that the guide vanes and the volute together serve as the kinetic energy conversion device of the second-stage impeller.

[0044] For Examples 1-3:

[0045] Preferably, the centrifugal pump blades and guide vanes appear alternately from the inlet to the outlet, and the centrifugal pump blades are closer to the inlet.

[0046] Preferably, a certain gap is left between the guide cone and the guide vanes fixed on the casing and the impeller to prevent the impeller from colliding with the casing when rotating.

[0047] Preferably, the outer side of the guide cone is specially designed to achieve a good transition of each stage of the centrifugal pump and optimize blood compatibility. The special design of the outer side of the guide cone is that the inlet, each stage of the centrifugal pump blades and each stage of the guide vane are equipped with a separate guide cone, and the guide cone can be concave, straight, protruding or a combination of the three.

[0048] Preferably, the number of blades and guide vanes of the centrifugal pump is fixed, and the number of blades and guide vanes of the centrifugal pump is equal or unequal.

[0049] Preferably, the number of centrifugal pump blades is 2 to 8.

[0050] Preferably, the centrifugal pump blade and the adjacent guide vane have opposite rotation directions in a top view.

[0051] It should be clear that the artificial heart pump model described in the specific implementation mode of this patent is not the optimal model described in this patent, but is only used as an example to more clearly express the content of this patent. According to the results of computational simulation or extracorporeal circulation experiments, by optimizing the blade shape, guide cone shape, impeller closure method, guide vane shape, guide vane number, impeller outer diameter, etc., an artificial heart pump model with a smaller appearance and better blood flow field can also be obtained.

[0052] In addition, in the specific implementation of the present invention, the energy fractions shared by the two-stage impellers are not equal, and the second-stage impeller as the main impeller has a larger impeller outer diameter. In practice, two impellers with the same outer diameter may be used according to the patient's physical condition, the placement of the heart pump in the body, and the operation conditions. At the same time, the number of impellers connected in series is not limited to 2.

[0053] The present invention does not specify the specific working mode of the artificial heart pump. Magnetic suspension, liquid suspension, magnetic liquid hybrid suspension and non-suspension bearing support used by the second generation artificial heart pump can be used. It only needs to add corresponding components used for support or suspension. The conventional flow guide groove (generally an arc-shaped groove on the outer surface of the flow guide cone) used to optimize the flow field structure can also be applied to the present invention.

[0054] The applicant declares that the above is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention shall fall within the protection scope and disclosure scope of the present invention.

Claims

1. An artificial heart pump impeller structure, characterized in that: The impeller structure includes two-stage centrifugal pump blades, two centrifugal pump upper cover plates and two-stage centrifugal pump guide cones; the impeller includes a corresponding outer shell on the outside, the outer shell includes an outer shell body, and 1 to 2 groups of guide vanes and 1 to 2 guide cones of the guide vanes are fixed inside; the centrifugal pump blades, the centrifugal pump upper cover plate and the centrifugal pump guide cone are combined into an inseparable impeller, or are fixed to each other through a central axis through a key or pin structure to form an integral impeller; the centrifugal pump blades and guide vanes appear alternately from the inlet to the outlet, and the centrifugal pump blades are closer to the inlet side; the two-stage centrifugal pump guide cone is arranged inside the outer shell as the lower cover plate of each stage of the impeller, and the guide cone of the guide vane is arranged below the centrifugal pump guide cone; The blood flows in from the inlet of the pump body, passes through the blunt tip of the first-stage centrifugal pump guide cone and is guided to the first-stage centrifugal pump blades. The blood is accelerated by the centrifugal force of the impeller to gain kinetic energy, then flows into the first-stage guide vanes, where the kinetic energy is converted into pressure energy, and then flows into the second-stage centrifugal pump blades to gain kinetic energy. Finally, it passes through the second-stage guide vanes A, where the kinetic energy is converted into pressure energy and flows out through the outlet. The combination of the impeller and the housing of the artificial heart pump constitutes the complete flow-through part of the artificial heart pump, i.e., the part in contact with the blood in the heart pump; The centrifugal pump guide cone adopts a hollow structure as the central axis.

2. The artificial heart pump impeller structure according to claim 1, characterized in that: A certain gap is left between the guide vane fixed on the casing and the guide cone of the guide vane and the impeller to prevent the impeller from colliding with the casing when rotating.

3. The artificial heart pump impeller structure according to claim 1 or 2, characterized in that: The outer side surface of the centrifugal pump guide cone is specially designed to achieve a good transition of each level of centrifugal pumps and optimize blood compatibility; The special design of the outer side of the guide cone is that the inlet, each stage of centrifugal pump blades and each stage of guide vanes are equipped with separate guide cones, and the guide cones are concave, straight, protruding or a combination of the three.

4. The artificial heart pump impeller structure according to claim 1, characterized in that: The number of blades and guide vanes of the centrifugal pump is fixed, and the number of blades and guide vanes of the centrifugal pump is equal or unequal; The number of blades of the centrifugal pump is 2 to 8.

5. The artificial heart pump impeller structure according to claim 1 or 4, characterized in that: The centrifugal pump blade and the adjacent guide vane have opposite rotation directions in a top view.

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