Blood pump housing component

Abstract

Providing a blood pump assembly, and a method for manufacturing and operating a blood pump assembly. [Solution] The blood pump assembly comprises a pump and an impeller blade rotatably coupled to the pump. The blood pump assembly also comprises a pump housing component, which is sized to pass through a body cavity and coupled to the pump. The pump housing component includes a circumferential wall extending around the axis of rotation of the impeller blade. The circumferential wall includes an inner circumferential wall surface and an outer circumferential wall surface. The circumferential wall also includes one or more blood drainage apertures. Each of the one or more blood drainage apertures is defined by an inner aperture portion and an outer aperture portion. Each inner aperture portion is chamfered between the inner circumferential wall surface and the outer circumferential wall surface.

Description

Technical Field

[0001] This application claims the benefit of priority under 35 U.S.C. § 119(e) to U.S. Provisional Patent Application No. 61 / 992,835, filed on May 13, 2014, the entire contents of which are incorporated herein by reference.

[0002] Technical Field The present disclosure relates to a blood pump assembly. More specifically, the present disclosure relates to a housing component of a blood pump assembly.

Background Art

[0003] Background Blood pump assemblies, such as intracardiac blood pump assemblies, are introduced into the heart to deliver blood from the heart to the arteries. The blood pump assembly draws blood from the left ventricle of the heart and expels the blood into the aorta. The blood pump assembly may be introduced percutaneously through the vasculature during a cardiac procedure. Specifically, this pump assembly may be inserted through the ascending aorta from the femoral artery and across the valve into the left ventricle by a catheter procedure. Pumping of the blood by the blood pump assembly may damage the blood or cause hemolysis when the blood is drawn through the blood pump assembly.

Summary of the Invention

[0004] Summary The devices and methods of manufacture described herein, as well as embodiments, provide a blood pump assembly having a housing component designed to reduce hemolysis and blood damage. The blood pump housing includes a drainage aperture designed to eject blood. The drainage aperture has an inner edge that is rounded by a chamfer or bevel. Rounding the inner edge of the aperture significantly reduces hemolysis. By using a chamfered inner edge for the drainage aperture, the blood can follow a flow pattern that can reduce shear stress compared to flow through an angular or unrounded edge. This reduces the number of red blood cells that rupture as the blood passes through the cannula and exits the blood pump housing, resulting in less hemolysis. For example, using a chamfered aperture inner edge for a blood pump housing can reduce hemolysis markers by more than 50% compared to a standard aperture edge.

[0005] In some embodiments, the non-adjacent inner and outer edges of the blood pump housing are chamfered. This reduces the profile of the struts of the blood pump housing component that are perpendicular to the direction of blood flowing out of the blood pump housing. Such a chamfered configuration significantly reduces the shear stress caused in the blood flowing out of the aperture and reduces the wake area caused in the blood flow by the struts of the pump housing. These effects can reduce hemolysis of the blood flow through the blood pump housing.

[0006] In some embodiments, the chamfered edge may include a 45° chamfer. In some embodiments, the chamfered edge may include chamfers of 10°, 20°, 30°, 40°, 50°, greater than 50°, or any other preferred angle. In some embodiments, the inner chamfered edge may include an alternative chamfer having two chamfered edges that are substantially parallel to the blood flow through the aperture, such that the two edges are positioned opposite each other on the support. In some embodiments, the inner edge of the aperture may be rounded instead of or in addition to being chamfered, or alternatively chamfered. In some embodiments, the rounded edge may include a radius of 40 to 105 micrometers. In some embodiments, the aperture edge may be rounded only in certain locations.

[0007] Various embodiments provide a blood pump assembly and a method for manufacturing a blood pump assembly. In one aspect, the blood pump assembly includes a pump and an impeller blade rotatably coupled to the pump. The blood pump assembly also includes a pump housing component, which is sized to pass through a body cavity and coupled to the pump. The pump housing component includes a circumferential wall having an inner surface and an outer surface. The circumferential wall includes one or more blood drainage apertures. Each blood drainage aperture is defined by an inner edge and an outer edge. Each inner edge of the blood drainage aperture includes a chamfered portion between the inner and outer surfaces.

[0008] In some embodiments, the blood pump assembly includes an inner edge with a chamfer of about 45°. In other embodiments, the blood pump assembly includes an outer edge that is rounded between the inner and outer surfaces of the wall. In certain embodiments, the rounded outer edge has a radius of 40 micrometers or greater than 40 micrometers. In other embodiments, the rounded outer edge has a radius of 105 micrometers or greater than 105 micrometers. In some embodiments, the blood pump assembly has an outer edge that is rounded overall. The blood pump assembly may be polished by electropolishing, mechanical polishing, or any other preferred method. In some embodiments, the blood pump assembly may include an inner edge having a first chamfered portion having a first chamfer angle and a second chamfered portion having a second chamfer angle greater than the first chamfer angle. The blood pump assembly may include an impeller blade positioned at least partially within the pump housing component. The blood pump assembly may include a pump housing component that is connected to the pump at a first end and to a cannula at a second end opposite the first end. The cannula component includes a blood inlet manifold. In some embodiments, the blood pump assembly also includes a pigtail extension connected to the blood inlet manifold.

[0009] In another aspect, the blood pump assembly includes a pump and an impeller blade rotatably connected to the pump. The blood pump assembly also includes a pump housing component, which is sized to pass through a body cavity and is connected to the pump. The pump housing component includes a circumferential wall having an inner surface and an outer surface. The circumferential wall includes a plurality of struts. Each strut has a first inner edge and a second inner edge, as well as a first outer edge and a second outer edge. Each first inner edge and second outer edge is chamfered between the inner and outer surfaces, and the first inner edge and the second inner edge are not adjacent. The circumferential wall also includes one or more blood drainage apertures. Each blood drainage aperture is positioned between pairs of struts.

[0010] In some embodiments, the first inner edge and the second outer edge of each of the multiple supports have a chamfer angle of about 45°. The blood pump assembly may be polished by electropolishing, mechanical polishing, manual polishing, or any preferred method. The blood pump assembly includes an impeller blade positioned at least partially within the pump housing component. The pump housing component is connected to the pump at a first end. The pump housing component is connected to the cannula component at a second end opposite to the first end. In some embodiments, the cannula component includes a blood inlet manifold. The blood pump assembly may include a pigtail extension connected to the blood inlet manifold.

[0011] In another aspect, a method for manufacturing a blood pump assembly includes the step of rotatably connecting an impeller blade to a pump. The method also includes the step of connecting the pump to a pump housing component. The pump housing component includes a circumferential wall extending around the axis of rotation of the propeller blade. The circumferential wall includes an inner surface and an outer surface located outside the inner surface in a radial direction with respect to the axis of rotation of the impeller. The method also includes the step of forming a plurality of blood drainage apertures in the circumferential wall. Each blood drainage aperture is defined by an inner edge and an outer edge. The inner edge of a blood drainage aperture includes a rounded edge portion and a chamfered edge portion.

[0012] In some embodiments, the method of connecting the pump to the pump housing component includes the step of positioning the impeller blades, which are rotatably connected to the pump, at least partially within the pump housing component. In some embodiments, the step of forming a plurality of blood drainage apertures includes forming the outer edges by tumbling. In certain embodiments, the outer edges are formed by rolling or by removing right-angle edges. In some embodiments, the step of forming a plurality of blood drainage apertures includes rounding the entire outer edge of the apertures between the inner and outer surfaces. In certain embodiments, the inner edges are rounded or chamfered by tumbling, rolling, or any other preferred method for removing right-angle edges. In some embodiments, the pump housing component is connected to the pump at a first end of the pump housing component, and the cannula component is connected to a second end of the pump housing component opposite to the first end. The cannula component includes a blood inlet manifold. In some embodiments, a pigtail extension may be connected to the blood inlet manifold. In some embodiments, the pump housing components are electropolished.

[0013] In another aspect, a method for operating a blood pump assembly includes the steps of rotating an impeller around a rotation axis to draw blood into the cannula portion of the blood pump assembly in a blood inlet manifold using a pump motor connected to the cannula portion by a pump housing component, and ejecting blood from the blood pump assembly through a plurality of drainage apertures in the circumferential wall. The pump housing component includes a circumferential wall extending around the rotation axis of the impeller blade. The circumferential wall includes an inner surface and an outer surface located outside the inner surface radially with respect to the rotation axis. Each of the plurality of drainage apertures is defined by an inner and outer aperture, the inner surface including a chamfered edge portion chamfered between the inner and outer surfaces. In some embodiments, the impeller blade is positioned at least partially within the pump housing component. In certain embodiments, the blood inlet manifold includes a plurality of inlet openings. In some embodiments, the method further includes the step of connecting the pigtail extension to a blood inlet manifold.

[0014] Those skilled in the art will likely recall variations and modifications after reviewing this disclosure. The disclosed features may be implemented in any combination and subcombinations (including multiple dependent and subcombinations) with one or more other features described herein. The various features described or illustrated above, including any of their components, may be combined or integrated into other systems. Furthermore, certain features may be omitted or not implemented at all. [Invention 1001] Pump and The pump is rotatably connected to an impeller blade, A pump that is sized to pass through a body cavity and is connected to the pump. A housing component that extends around the rotation axis of the impeller blade Including a wall, the surrounding wall is Inner self, Outer surface, and One or more drainage apertures, each defined by an inner and outer border. Blood drainage aperture It has, Each inner edge is chamfered between the inner surface and the outer surface. Pump housing components and A blood pump assembly comprising: [Invention 1002] A blood pump assembly according to the present invention 1001, wherein each inner edge includes a chamfered portion of approximately 45°. [Invention 1003] Each outer edge is rounded between the inner surface and the outer surface, according to the present invention 1001 or 1002. Blood pump assembly. [Invention 1004] Each rounded outer edge has a radius of approximately 40 micrometers or more than approximately 40 micrometers. A blood pump assembly according to any of the present invention 1001 to 1003. [Invention 1005] Each rounded outer edge has a radius of approximately 10⁵ micrometers or more than approximately 10⁵ micrometers. A blood pump assembly having any of the present invention 1001 to 1004. [Invention 1006] Each outer edge is rounded, according to any of the blood pump assemblies of the present invention 1001 to 1005. Nburi. [Invention 1007] The pump housing component is electropolished, according to any of the inventions 1001 to 1006. A blood pump assembly. [Invention 1008] Each inner edge has a first chamfered portion having a first chamfer angle, and a portion that is greater than the first chamfer angle. Any of the present invention 1001 to 1007, including a second chamfered portion having a large second chamfer angle. That blood pump assembly. [The present invention 1009] The impeller blade is at least partially positioned within the pump housing component The blood pump assembly according to any one of the present inventions 1001 to 1008 [The present invention 1010] The pump housing component is connected to the pump at a first end and the pump housing component is connected to a cannula component at a second end opposite the first end The blood pump assembly according to any one of the present inventions 1001 to 1009 [The present invention 1011] The cannula component includes a blood inlet manifold, the blood pump assembly according to any one of the present inventions 1001 to 10 10 [The present invention 1012] The blood pump assembly according to any one of the present inventions 1001 to 1011 further includes a pigtail extension connected to the blood inlet manifold [The present invention 1013] A pump An impeller blade rotatably connected to the pump A pump housing component sized to pass through a body cavity and connected to the pump, the pump housing component extending around the axis of rotation of the impeller blade and including a peripheral wall The peripheral wall includes An inner surface An outer surface Each of a plurality of struts has a first inner edge portion, a second inner edge portion, a first outer edge portion, and A second outer edge portion, the first inner edge portion and the second outer edge portion are chamfered between the inner surface and the outer surface of the peripheral wall, and the first inner edge portion and the second outer edge portion are not adjacent The plurality of struts, and ​​​​Each of the one or more blood drainage apertures is positioned between the pair of the multiple support columns. or one or more blood drainage apertures including, Pump housing components and A blood pump assembly comprising: [Invention 1014] Each of the first inner edge and each of the second outer edges of the plurality of support columns has a chamfer angle of approximately 45°. , blood pump assembly according to the present invention 1013. [Invention 1015] The pump housing component is electropolished, according to the present invention 1013 or 1014. Blood pump assembly. [Invention 1016] The impeller blades are at least partially inside the pump housing component. A blood pump assembly according to any of the present invention 1013 to 1015, positioned at [location]. [Invention 1017] The pump housing component is connected to the pump at the first end. Furthermore, the pump housing component is located at the second end opposite the first end. In this, the blood of any of the inventions 1013 to 1016 is connected to the cannula component. Liquid pump assembly. [Invention 1018] The cannula component includes a blood inlet manifold, according to the present invention 1013-10. One of 17 blood pump assemblies. [Invention 1019] This invention further comprises a pigtail extension connected to the aforementioned blood inlet manifold. A blood pump assembly from either Meiji 1013-1018. [Invention 1020] The step of rotatably connecting the impeller blades to the pump; In the step of connecting the pump to the pump housing component, the pump housing The impeller component includes a peripheral wall that extends around the rotation axis of the impeller blade, The peripheral wall comprises an inner surface and an outer surface located outside the inner surface in a radial direction with respect to the rotation axis of the impeller. Stages including; and A step of forming multiple blood drainage apertures on the peripheral wall, the multiple blood drainage apertures Each drainage aperture is defined by an inner and outer edge, the inner edge being a rounded edge. A step including one of a portion and a chamfered edge portion. A method for manufacturing a blood pump assembly, including the following: [Invention 1021] The step of connecting the pump to the pump housing component is performed on the pump. The impeller blades, which are possibly connected, are at least partially connected to the pump housing. Manufacturing a blood pump assembly of the present invention 1020, including positioning within a poronid. method. [Invention 1022] The step of forming the plurality of blood drainage apertures is performed by tumbling the outer edge A method for manufacturing a blood pump assembly of the present invention 1020 or 1021, comprising forming a [part of the present invention]. [Invention 1023] The step of forming the plurality of blood drainage apertures involves rolling the outer edge portion A method for manufacturing any of the blood pump assemblies of the present invention 1020 to 1022, including forming Law. [Invention 1024] The step of forming the plurality of blood drainage apertures is performed by removing the right-angled edges. A blood pump assembly according to any of invention 1020 to 1023, including forming the outer edge portion The method of manufacture. [Invention 1025] The step of forming the plurality of blood drainage apertures is the outer edge between the inner surface and the outer surface. A blood pump assembly according to any of invention 1020 to 1024, including rounding the entire part. A method for manufacturing li. [Invention 1026] The pump housing component is the first of the pump housing component The end is connected to the pump, and the method is a cannula component The first end is connected to the second end of the pump housing component, opposite to the first end. A blood pump assembly according to any of the inventions 1020-1025 is manufactured, further comprising the step of manufacturing method. [Invention 1027] The cannula component includes a blood inlet manifold, according to the present invention 1020-10 A method for manufacturing any of the 26 blood pump assemblies. [Invention 1028] This further includes the step of connecting the pigtail extension to the blood inlet manifold. A method for manufacturing a blood pump assembly according to any of inventions 1020 to 1027. [Invention 1029] The present invention further includes the step of electropolishing the pump housing component, as described in invention 1020~ A method for manufacturing any of the 1028 blood pump assemblies. [Invention 1030] The pump housing component connects to the cannula portion of the blood pump assembly. Using a connected pump motor, the cannula portion in the blood inlet manifold In order to draw blood into the pump, the impeller is rotated around the rotating shaft, The housing component includes a peripheral wall extending around the rotation axis of the impeller blade. Furthermore, the peripheral wall is located on the outer side of the peripheral wall surface in a radial direction with respect to the axis of rotation. A stage including the exterior surface of the wall; and Blood is ejected from the blood pump assembly through multiple drainage apertures on the peripheral wall. In this stage, each of the multiple blood drainage apertures is located at the inner edge of the aperture. and defined by the outer edge of the aperture, the inner edge of the aperture is defined by the inner surface of the peripheral wall and the outer surface of the peripheral wall. Steps including chamfered edges between surfaces A method for operating a blood pump assembly, including [specific details omitted]. [Invention 1031] The impeller blades are at least partially inside the pump housing component. A method for operating the blood pump assembly of the present invention 1030, which is positioned as follows. [Invention 1032] The blood inlet manifold includes a plurality of inlet openings, according to the present invention 1030 or How to operate the 1031 blood pump assembly. [Invention 1033] This further includes the step of connecting the pigtail extension to the blood inlet manifold. A method for operating a blood pump assembly according to any of inventions 1030 to 1032. [Brief explanation of the drawing]

[0015] Those skilled in the art will understand that the accompanying drawings are for illustrative purposes only and are not intended to limit the scope of the subject matter described herein. The drawings are not necessarily to a uniform scale, and in some cases, different aspects of the subject matter disclosed herein may be exaggerated or enlarged in the drawings to aid in the understanding of different features. In the drawings, similar reference symbols generally refer to similar features (e.g., functionally similar elements and / or structurally similar elements). [Figure 1]A perspective view of a blood pump housing component including a chamfered edge is shown according to an exemplary embodiment. [Figure 2] A top cross-sectional view of an impeller including rounded edges and chamfered edges is provided according to an exemplary embodiment. [Figure 3] This shows the shear stress related to blood passing through pump housing supports with different cross-sectional geometric shapes. [Figure 4] This shows the shear stress related to blood passing through pump housing supports with different cross-sectional geometric shapes. [Figure 5] This shows the shear stress related to blood passing through pump housing supports with different cross-sectional geometric shapes. [Figure 6] This shows the shear stress related to blood passing through pump housing supports with different cross-sectional geometric shapes. [Figure 7] The box plot shows a reduction in hemolysis associated with chamfered housing components. [Figure 8] A perspective view of a blood pump assembly according to an exemplary embodiment is shown. [Figure 9] A method for manufacturing a blood pump assembly according to an exemplary embodiment is illustrated.

[0016] The features and advantages of the concept of the present invention disclosed herein will become clearer upon reading the following description in conjunction with these drawings. [Modes for carrying out the invention]

[0017] Detailed Description The following is a more detailed description of various concepts of the system and method of the present invention for providing a blood pump assembly, and of embodiments of the system and method of the present invention. The disclosed concepts are not limited to any particular form of embodiment, and it should be understood that the various concepts outlined above and described in more detail below may be implemented in any of the many possible methods. Examples of specific embodiments and applications are provided primarily for illustrative purposes.

[0018] The systems, devices, and methods described herein reduce hemolysis and similar blood damage caused by blood flow through a blood pump. Among various design aspects, the use of the blood pump assembly reduces the occurrence of hemolysis by adjusting the aperture edge of the blood pump housing or by making additional adjustments to the housing to ensure proper positioning.

[0019] Figure 1 shows a diagram of a blood pump housing component 102 including chamfered inner edges 105c-f according to an exemplary embodiment. The pump housing component includes an upstream end 110, a downstream end 111, a peripheral wall 115, an inner surface 107, an outer surface 108, a plurality of aperture surrounding surfaces 104 extending between the inner surface 107 and the outer surface 108, inner edges 116 and outer edges 118 defining blood drainage apertures 103a-f, and supports 106a-f. The downstream end 111 of the pump housing component 102 is configured to connect to a pump (not shown in the figure), and the upstream end 110 is configured to connect to a cannula (not shown in the figure). In some embodiments, the pump housing component 102 is configured to enclose the pump and house an impeller rotatably connected to the pump. The peripheral wall 115 of the pump housing component 102 is substantially cylindrical and extends around the axis 101 from the downstream end 111 to the upstream end 110. In some embodiments, the axis 101 is the rotation axis of an impeller rotatably connected to a microaxial flow pump connected to the pump housing component 102 and positioned within the pump housing component 102. The blood drainage apertures 103a-f are configured to eject the blood drawn into a cannula connected to the pump housing component by the pump and the impeller connected to the pump. Six apertures are shown in the figure, but any preferred number of apertures (e.g., 1, 2, 3, 4, 5, 7, 8, 10, more than 10, or any preferred number) may be included. The blood drainage apertures 103a-f include apertures having rounded corner portions 112a-f, but in some embodiments, the apertures may include rounded apertures, circular apertures, or apertures of any preferred shape. The blood drainage apertures 103a-f extend from the inner surface 107 to the outer surface 108 through the peripheral wall 115 of the pump housing component 102. The aperture periphery surfaces 104a-f of the blood drainage apertures 103a-f each include rounded edge portions 105a-f.The rounded edge portions 105a-f may include an inner edge portion 116 formed by the inner surface 107 and the aperture surrounding surfaces 104a-f. The rounded edge portions 105a-f may include an outer edge portion 118 formed by the outer surface 108 and the aperture surrounding surfaces 104a-f, instead of, or in addition to, the inner edge portion 116. The rounded edge portions 105a-f may extend from the inner surface 107 to the outer surface 108. The inner edge portion 116 or outer edge portion 118 of the blood drainage aperture 103a-f is chamfered to form chamfered surfaces 105c-f. In certain embodiments, the chamfered surfaces 105c-f are bordered on one or both sides by a lark'stongue 117. In some embodiments, the aperture periphery surfaces 104a-f are rounded along the entire inner edge 116 or outer edge 118. In certain embodiments, the aperture periphery surfaces 104a-f are rounded along only a portion of the inner edge 116 or outer edge 118. The support columns 106a-f are located between the blood drainage apertures 103a-f along a portion of the aperture periphery surfaces 104a-f. In some embodiments, the geometry of the support columns 106a-f located between the blood drainage apertures 103a-f varies depending on the size, number, and distribution of the blood drainage apertures 103a-f and the rounded or chamfered edges 105c-f of the blood drainage apertures 103a-f. The geometry of the support column 106 may also vary by changing the curvature or chamfer of the inner edge 116 and outer edge 118.

[0020] The pump housing component 102 may be made of metal. In some embodiments, the pump housing component 102 is electropolished. The rounded edge portions 105a to f of the aperture periphery surfaces 104a to f may be formed by tumbling, rolling, machining, or any other suitable material removal process such that the aperture periphery surfaces 104a to f are rounded in the region between the inner surface 107 and the outer surface 108. Before rounding a portion of the inner edge 116 or outer edge 118, the aperture periphery surfaces 104a to f and the inner surface 107 or outer surface 108 may include edges that are chamfered or configured at a 90-degree angle. Thus, the aperture periphery may be rounded or chamfered to remove right-angle edges.

[0021] Figure 2 provides a top cross-sectional view of a blood pump housing component 102 including a rounded edge according to an exemplary embodiment. As shown in Figure 1, the blood drainage aperture defined in cross-section by struts 206a-f includes chamfered inner edges 209a-f and rounded outer edges 205a-f. In exemplary embodiments, both the inner and outer edges may be chamfered, both rounded, or the inner edges may be rounded and the outer edges may be chamfered. In some embodiments, the inner edges may have a radius including, but not limited to, 40 micrometers. In some embodiments, the outer edges may have a radius including, but not limited to, 105 micrometers.

[0022] Figures 3-6 show the results of computer tests of shear stress related to blood flow around supports with different cross-sectional geometric shapes. Each figure illustrates the flow of blood exiting the blood pump housing 102 through the drainage aperture 103 and support 106, such that the appearance of Figures 3-6 corresponds to a portion of the cross-sectional view shown in Figure 2. In each figure, the blood flow is generally from left to right, from the inside to the outside of the blood pump housing. As illustrated, the blood is not purely discharged radially from the inside of the blood pump housing, but also has a considerable tangential velocity component. The direction of blood flow and shear stress perceived at each point is illustrated in each figure by arrows. The magnitude of the shear stress at each point is indicated by the shading of the arrows. Brighter shading indicates lower shear stress, and darker shading indicates higher shear stress.

[0023] Figure 3 shows a column cross-section 302 having angular corners 303a to d, which create a wake 304 with a width of 306. The column cross-section 302 creates a region 308 with relatively high stress within the blood flow. Figure 4 shows a column cross-section 402 having chamfered corners 403a to 403b and angular corners 403c to d. The column cross-section 402 creates a wake 404 with a width of 406, creating a region 408 with relatively high stress within the blood flow. Figure 5 shows a column cross-section 502 having rounded corners 503a to d, which create a wake 504 with a width of 506. The column cross-section 502 creates a region 508 with relatively high stress within the blood flow. Figure 6 shows a support column, which has a cross section 602 having chamfered corners 603a-b and angular corners 603c-d, where corners 603a and 603b are not adjacent. The column cross section 602 creates a wake 604 with a width 606. The column cross section 602 creates a region 608 in the blood flow where shear stress is increased. As illustrated in Figures 3-6, the cross-sectional shape of the column affects the shear stress and direction of the blood flow exiting the drainage aperture. This is because the blood flowing from the inside to the outside of the blood pump housing must face the column and flow around it. As a result, areas of high stress 308, 408, 508, and 608 are created when the blood separates around the column. In addition, this causes wakes 304, 404, 504, and 604 behind the column. The size of each wake can accommodate the disruption of the flow pattern induced by the geometry of each support. Reducing the shear stress on red blood cells exiting the blood pump housing lowers the traumatic nature of the flow pattern, thus reducing the likelihood of cell damage and rupture (e.g., hemolysis). This also allows the cells to maintain their shape and elasticity without cell rupture.

[0024] As illustrated in Figures 3-6, different column geometry shapes result in different flow patterns and associated stresses. Column cross section 302 causes relatively large flow collapse due to its right-angle corners 303a-d. The high-stress region 308 along the lower edge of column cross section 302 indicates a high-pressure area where blood moves along the long side of the column inside the blood pump housing and is forced to deviate from its path as it turns around the angular corner 303d of column 302 and passes through the drainage aperture. Outside the blood pump housing, the wake 304 behind the column is large compared to the size of column 302. Column cross section 502 with rounded corners 503a-d also has a similar relatively high-stress region 508 as blood turns around the column and flows out through the drainage aperture. Outside the blood pump housing, the wake behind the rounded strut 504 is narrower than that of strut 302. The chamfered strut 402 has a high-stress area 408 and a relatively large wake behind strut 404, which indicates that this geometry causes relatively significant obstruction to blood flow.

[0025] The column cross-section 602 causes less flow disruption, resulting in lower shear stress compared to column cross-sections 302, 402, and 502 (e.g., 10%, 20%, 30%, or less). As blood flows around the column and through the drainage aperture, the angular leading edge 603c directed inward into the blood pump housing and the chamfered edges 603a-b substantially parallel to the flow of blood exiting the blood pump housing create a relatively small area 608 with increased shear stress. The wake 604 downstream of column 602 is relatively small (e.g., about 50%, 30%, 20%, or less than 20% of the size of the wake 304) and is accompanied only by a relatively small flow collapse area. Thus, the chamfered geometric shape of the support column 604 results in relatively little flow collapse, which can reduce hemolysis compared to the support column cross-sections 302, 402, and 502.

[0026] Figure 7 shows a box plot 700 comparing the results of a hemolysis test between a blood pump assembly with a standard right-angle drainage aperture edge 704 and a blood pump assembly with a chamfered inner aperture edge 707 such that the cross-sectional geometry of the support column is similar to the geometry shown in Figure 4. The blood pump assembly with the right-angle drainage aperture edge was electropolished. The blood pump assembly with the chamfered edge, which was created by machining, was electropolished and tumbling. These blood pump assemblies were identical in all respects except for the geometry of the drainage aperture and the method of forming those geometry. The blood pump assemblies with the right-angle drainage aperture and the blood pump assemblies with the chamfered drainage aperture were mounted in the same HemolysisMockLoops, part number 0046-6667. This loop draws blood from a main reservoir heated to 37°C ± 2°C by a constant temperature bath. Blood is pumped through the blood pump housing by a blood pump while maintaining a pressure difference. The conditions selected for the test are chosen to represent the worst-case scenario expected to occur during device operation. Hemolysis tests were performed according to ASTM Standard F1841-97 (2005). Plasma free hemoglobin concentration and hematocrit were assessed at the start and end of the test according to the cyanohemoglobin method. The y-axis 702 shows the modified hemolysis index (MIH), which is the amount of hemoglobin released into the plasma normalized by the amount of hemoglobin contained in the total volume of blood pumped through the device. Box plot 700 shows that the mean MIH was reduced by more than 50% by the use of a chamfered edge compared to a standard right-angle drainage aperture. Thus, hemolysis is significantly reduced by the use of a chamfered aperture design without changing the geometry of the impeller blade or other aspects of the pump design.

[0027] The aforementioned blood pump housing component may be incorporated into a blood pump assembly. Figure 8 shows such a blood pump assembly 800 according to a particular embodiment. The blood pump assembly 800 includes a blood pump 801, a housing component 802, an impeller blade 803, a cannula 804, a blood inlet manifold 805, and a pigtail extension 806. The blood pump 801 is connected to the cannula 804 via the housing component 802. The features of the housing component are similar to those of housing components 102 and 202 in Figures 1 and 2, respectively. The housing component 802 includes one or more apertures 103 having an inner edge 116 and an outer edge 118. In some embodiments, either or both of the inner edge 116 and the outer edge 118 may include a rounded edge portion or a chamfered edge portion 105 that helps reduce hemolysis. According to some embodiments, the rounded edge portion or chamfered edge portion may be obtained by machining the chamfer or radius, or by tumbling. The chamfered edge portion may include a symmetrical chamfer or an asymmetrical chamfer. The chamfer may, in no particular way, include a 45° chamfer.

[0028] The blood pump assembly 801 includes a catheter 807 connected to the blood pump 801. In some embodiments, the blood pump 801 includes a motor. In such cases, the catheter 807 may house wires connecting the pump motor to one or more electrical controllers or other sensors. In certain embodiments, the blood pump is driven by an external pump portion (e.g., via a flexible drive shaft). The catheter 807 may also house other components, such as a purging fluid conduit or other conduit configured to receive a guidewire. The housing component 802 includes one or more apertures or openings configured to eject or discharge blood drawn into the cannula 804 out of the blood pump assembly 800. In some embodiments, the housing component 802 encloses the blood pump 801. In some embodiments, the blood pump 801 includes a microaxial flow pump having a pumping capacity that non-limitingly includes ranges of 5 L / min and 2.5 L / min. In some embodiments, the blood pump 801 includes a microaxial flow pump having a diameter that non-limitingly includes a range of 21 Fr to 10 Fr.

[0029] The blood pump 801 includes an impeller blade 803 rotatably connected to the blood pump 801. The cannula 804 may include an elongated flexible hose portion, and may also include a shape memory coil, such as a nitinol coil. In some embodiments, the cannula 804 is made of polyurethane material at least partially. In some embodiments, the cannula 804 has a diameter that is not limited to the range of 12 Fr to 9 Fr. In some embodiments, the cannula 804 includes a 45° bend. The cannula 804 includes a blood inlet manifold 805 connected to the cannula 804 at its proximal end to receive blood flow into the blood pump assembly 800. The blood inlet manifold 805 includes one or more blood inlet openings located within the inlet manifold 805. The blood inlet manifold 805 has a pigtail extension 806 connected to the cannula 804. In some embodiments, the pigtail extension has a diameter of 6 Fr. In some embodiments, the pigtail extension has a diameter in the range of 4 to 8 Fr.

[0030] The pigtail extension 806 assists in stabilizing the blood pump assembly 800 and positioning it correctly within the left ventricle. In some embodiments, the blood pump assembly 800 is inserted percutaneously through the femoral artery and into the left ventricle. When properly positioned, the blood pump assembly 800 delivers blood from the inlet area of ​​the blood inlet manifold 805 located inside the left ventricle, through the cannula 804, to the outlet opening of the housing component 802 positioned within the ascending aorta.

[0031] According to several embodiments, the pigtail extension 806 can be configured from a straight configuration to a partially curved configuration. Thus, the pigtail extension 806 may be composed of a flexible material at least partially. According to several embodiments, the pigtail extension 806 may have dual rigidity. More specifically, in some embodiments, the pigtail extension 806 includes a distal portion 810 composed of a material that is softer or less rigid than the proximal portion 808 of the pigtail extension 806. The proximal portion may be composed of a different material from the blood inlet manifold 805 and the cannula 804, and may have a different structure from them. The proximal portion 808 may be sufficiently rigid to substantially prevent buckling of the proximal portion 808, thereby reducing the possibility of the blood outlet opening or drainage aperture of the housing component 802 moving into the aortic valve or ventricle of the heart, while keeping the blood inlet opening of the blood inlet manifold 805 outside the ventricular apex. The distal portion 810 of the pigtail extension 806 is flexible relative to the proximal portion 808 to provide a non-traumatic tip for contacting the ventricular wall and to allow for guidewire loading. In some embodiments, the proximal portion 808 and distal portion 810 of the pigtail extension are made of different materials having different rigidities. In some embodiments, the proximal portion 108 and distal portion 810 of the pigtail extension are made of the same material having different rigidities.

[0032] Figure 9 illustrates a method 900 for manufacturing a blood pump assembly according to a particular embodiment. Method 900 may be carried out to manufacture a blood pump assembly 800 in any of the embodiments described above, which non-limitingly include a blood pump assembly having a blood drain aperture having a rounded edge, a chamfered rounded edge, or any combination thereof, wherein the edge formed by the peripheral and inner surfaces of the aperture, by the peripheral and outer surfaces of the aperture, or both, may be rounded. Method 900 may be carried out to manufacture a blood pump assembly having a blood drain aperture having a chamfered or rounded edge, where only the entire or some portion of the peripheral edge and inner or outer surface is chamfered or rounded. Method 900 may be carried out to manufacture a blood pump assembly having a blood drain aperture having a chamfered or rounded edge. In step 904, the blood pump is connected to a pump housing, such as a pump housing 802. The pump housing includes a circumferential wall extending around the rotation axis of the impeller blades, the circumferential wall including an inner surface and an outer surface located outside the inner surface radially with respect to the rotation axis of the impeller. In step 906, several blood drainage apertures, such as a blood drainage aperture 803, are formed in the wall of the blood pump housing 802. Each of the multiple blood drainage apertures is defined by an inner aperture portion and an outer aperture portion, the inner aperture portion including one of a rounded edge portion and a chamfered edge portion. Depending on the embodiment, the pump housing components may be made of metal. In some embodiments, the pump housing components are electropolished. The chamfered edge portion of the aperture periphery surface may be formed by tumbling, rolling, machining, material removal, or any other preferred fabrication process such that the aperture periphery surface is rounded at least partially in the inner or outer edge region.Before rounding a portion of the inner or outer edge, the aperture periphery surface and the inner or outer surface 108 may include edges that are chamfered or configured at a 90-degree angle. Thus, the inner or outer edge may be rounded or chamfered to remove right-angle edges.

[0033] Where used herein, “approximately,” “about,” “substantially,” and similar terms are intended to have a broad meaning consistent with the common usage accepted by those skilled in the art in the field to which the subject matter of this disclosure belongs. It should be understood by those skilled in the art considering this disclosure that these terms allow for the description of certain features, but do not limit those features to the precise numerical ranges provided. Accordingly, these terms should be interpreted as indicating that any non-substantial or non-material modification or alteration to the subject matter is deemed to fall within the scope of this disclosure.

[0034] For the purposes of this disclosure, the term “connected” means that two members are connected to each other directly or indirectly. Such connections may be stationary or movable. Such connections may be realized by the two members, or by the two members and any additional intermediate members formed integrally with each other as a single unit, or by the two members, or by the two members and any additional intermediate members attached to each other. Such connections may be permanent or removable or detachable.

[0035] It should be noted that the orientation of various elements may differ according to other exemplary embodiments, and that such variations are intended to be covered by this disclosure. It is recognized that features of the disclosed embodiments may be incorporated into other disclosed embodiments.

[0036] Importantly, it should be noted that the structures and arrangements of the apparatus or its components shown in the various exemplary embodiments are merely illustrative. Although only a few embodiments are described in detail in this disclosure, it will be readily apparent to those skilled in the art that numerous modifications are possible without significantly departing from the novel teachings and merits of the disclosure (e.g., variations in the size, dimensions, structure, shape, and proportions of various elements, parameter values, mounting arrangements, material use, color, orientation, etc.). For example, elements shown as being formed as a single unit may be constructed as multiple parts or elements, the positions of elements may be reversed or otherwise modified, and the nature or number of separate elements or positions may be modified or changed. The order of any steps of a process or method may be changed or rearranged according to alternative embodiments. Other substitutions, modifications, changes, and omissions are also possible for the designs, operating conditions, and arrangements of the various exemplary embodiments without departing from the scope of this disclosure.

[0037] While various embodiments of the present invention have been described and illustrated herein, it is expected that those skilled in the art will readily conceive of various other mechanisms and / or structures for performing the functions described herein and / or obtaining one or more of the results and / or advantages described herein, and that each of such variations and / or modifications will fall within the scope of the embodiments of the invention described herein. More generally, it will be readily apparent to those skilled in the art that the parameters, dimensions, materials, and configurations described herein are intended to be illustrative unless otherwise noted, and that the actual parameters, dimensions, materials, and / or configurations will vary depending on the specific application in which the teachings of the present invention are used. Those skilled in the art will be able to recognize or verify numerous equivalents to the specific embodiments of the present invention described herein by routine experimentation alone. Therefore, it should be understood that the above embodiments are presented only as examples, and that embodiments of the invention may be made within the scope of the appended claims and their equivalents, beyond those specifically described and claimed. Embodiments of the invention of this disclosure relate to the individual features, systems, articles, materials, kits, and / or methods described herein. In addition, any combination of two or more such features, systems, articles, materials, kits, and / or methods is included within the scope of the inventions of this disclosure, provided that such features, systems, articles, materials, kits, and / or methods are not contradictory to each other.

[0038] Furthermore, at least one embodiment of the techniques described herein may be carried out in the manner provided above. The actions performed as part of the method may be ordered in any preferred manner unless otherwise specified. Thus, embodiments may be constructed such that the actions are performed in a different order than those exemplified, including performing some actions simultaneously, even if they are shown as sequential actions in the exemplary embodiments.

[0039] As used herein and in the claims, the indefinite articles “a” and “an” should be understood to mean “at least one” unless otherwise explicitly stated. As used herein and in the claims, “or” should be understood to have the same meaning as “and / as well as / or” as defined above. For example, when separating items in an enumeration, “or” or “and / as well as / or” should be interpreted as inclusive, meaning that it includes at least one, but also two or more of the elements or enumeration of elements, and optionally, additional items that are not enumerated. Only terms that are explicitly stated not to include, such as “only one of” or “exactly one of,” mean that it includes exactly one element of the elements or enumeration of elements. In general, the terms “or” as used herein should be interpreted as referring to something exclusive (i.e., “one or the other, but not both”) only when preceded by an exclusive term such as “either,” “one of,” “only one of,” or “strictly one of.”

[0040] When used herein and in the claims, the phrase “at least one” with respect to one or more elements means at least one element selected from any one or more elements in the element enumeration, but does not necessarily include at least one of each element specifically listed in the element enumeration, nor does it exclude any combination of elements in the element enumeration. This definition also makes it possible that there may be elements different from those specifically identified in the element enumeration to which the “at least one” phrase refers, whether or not they relate to those specifically identified elements. Therefore, as a non-restrictive example, “at least one of A and B” (or equivalently “at least one of A or B” or equivalently “at least one of A and / or B”) may, in one embodiment, refer to at least one A that has no B (and optionally includes elements other than B) and may include any two or more elements; in another embodiment, refer to at least one B that has no A (and optionally includes elements other than A) and may include any two or more elements; and in yet another embodiment, refer to at least one A that includes two or more elements and at least one B that includes any two or more elements (and may optionally include other elements), and so on.

[0041] In the claims and the above specification, all transitional phrases such as “equipped with,” “include,” “carry,” “have,” “contain,” “accompany,” “hold,” and “composed of” should be understood to be non-restrictive, meaning they include but are not limited to.

[0042] Unless otherwise stated, the claims should not be read as being limited to the order or elements described. It should be understood that various modifications in form and detail can be made by those skilled in the art without departing from the spirit and scope of the attached claims. All embodiments that fall within the spirit and scope of the following claims and their equivalents are claimed.

Claims

[Claim 1] Pump and The pump is rotatably connected to an impeller blade, A pump housing component, sized to pass through a body cavity and connected to the pump, includes a circumferential wall extending around the rotation axis of the impeller blade, the circumferential wall being, Inner self, exterior, Each of the multiple support columns has a first inner edge and a second inner edge, and a first outer edge and a second outer edge, and the first inner edge and the second outer edge are chamfered between the inner surface of the circumferential wall and the outer surface of the circumferential wall, and Each of the one or more drainage apertures is positioned between the pair of support columns. A blood pump assembly comprising:

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