WO2012112129A1

WO2012112129A1 - Axial-flow heart pump

Info

Publication number: WO2012112129A1
Application number: PCT/TR2012/000027
Authority: WO
Inventors: Koral TOPTOP
Original assignee: Individual
Current assignee: Individual
Priority date: 2011-02-15
Filing date: 2012-02-07
Publication date: 2012-08-23
Anticipated expiration: 2013-08-15
Also published as: TR201101396A1

Abstract

Present invention is concerned with axial-flow heart pump (1) that contains pump housing (2), flow straightener (9), diffuser (5), rotor (7), double blade sets -that are exterior blades (6) located exterior surface of extruded rotor and interior blades (8) located inside of extruded rotor (7) - and additionally the other components of brushless DC motor as stator coils (3), position sensors (4), permanent magnets (13) and mechanic and/or magnetic bearings. The specifications of axial-flow heart pump (1) is converting the motional energy that is produced with interaction between stator coils (3) and magnetic fluxes produced by permanent magnets (13) located in rotor (7) block that are components of brushless DC motor, to the kinetic energy to blood via rotation of exterior and interior blades (6 & 8) that are located on and inside of rotor (7) in order to accelerate and pressurize blood.

Description

AXIAL-FLOW HEART PUMP DESCRIPTION

TECHNICAL FIELD

The present invention had been developed as purpose of recovering decreased performance of heart -that is caused by failure and disorder of heart functions- by implanting it in body with surgery for pumping blood from heart to aorta and providing longer and higher quality life for patients.

Present invention relates to a mechanism that accelerates blood flow and pressurizes it via rotational motion of rotary block (rotor) inside of invention (axial- flow heart pump) and blades (impeller) that are installed on the exterior surface and the inside of rotor.

The present invention relates to an axial-flow heart pump that solves the decrease of pumping volume problem caused by narrowing blood flow channel located at exterior of rotor, by extrusion inside of rotor block and creating additional (alternative) blood flow channel as alternative to the blood flow channel at exterior of rotor.

The present invention relates to installing blade sets to exterior surface of rotor and to the alternative blood flow channel created in rotor.

Especially present invention relates to axial-flow heart pump that reduces the problem of permanent magnet installation via its special design and reduces disadvantage of motor efficiency decrease caused by permanent magnet installation and provides blood flow by accelerating blood particles and pressurizing them via rotational motion of specially designed blades inside and outside of rotor.

CURRENT TECHNIQUES

Disorder of heart functions cause decrease of heart performance, a condition called Chronic Heart Failure (CHF). Blood flow from heart to aorta, namely to the human circulation system, decreases to insufficient level for the body as a result of CHF. Although, patients at last stage of CHF can survive with heart transplantation, insufficient amount of available hearts for transplantation causes huge risk for patients. During the waiting period for an available heart, CHF patients can survive with Mechanical Circulatory Support Machines (MCSM) that supply sufficient blood flow. However, MCSM systems oblige CHF patients to stay in a clinic because of their sizes. As a result, heart pumps were developed to provide a better alternative to CHF patients. When surgically implanted in human body, artificial heart pumps increase survival rate and life quality of CHF patients until a suitable heart is found. Even though they were all developed for the same purpose, artificial heart pumps explained here are based on different structures.

The explained artificial heart pumps were divided to two different categories as displacement pumps and rotary pumps in terms of head pressure (pumping pressure) and blood pumping volume capacities. The displacement pump is a system that compresses the blood in closed volume and pressurizes it by applying force to compressed blood via piston, wheel or another mechanical system. So, blood flow is produced by increasing its pressure in this type of heart pumps. Rotary pumps provide blood flow and head pressure thanks to transferring motional energy that produced by motor, to the blood as kinetic energy via contact between blades (impeller) and blood particles. Blood cells can be damaged because of contact between blades and blood particles; Hemolysis term is used in the terminology for evaluating the amount of damaged blood cells. Rotary heart pumps cause less hemolysis on the blood than displacement pump and provide more advantage than displacement pump with easier implantation to body and mobility by patient thanks to their smaller size. Also, the other advantage of the rotary heart pumps is that they allow easier control of blades (impeller) rotational velocity with motor feed controller for desired flow and head pressure. Rotary heart pumps are preferred more than displacement pumps thanks to these advantages. Explained rotary pumps can be divided to 3 categories as Axial-Flow, Centrifugal (Radial) and Mixed (Diagonal) pumps in terms of rotor, blades and inlet and outlet geometry of pump. Axial-flow pump produce high flow volume under low head pressure, Centrifugal Pumps provide low flow volume under high head pressure and mixed flow pumps produce high flow volume under high head pressure. Axial-flow and Centrifugal Pumps are more preferred for CHF patients in terms of hemodynamic performance of pumps as flow velocity at outlet of pump, pumping volume, head pressure and physiologic effects on body as hemolysis amount. Axial-flow pumps are smaller and lighter than Centrifugal Pumps; therefore, implantation of Axial flow umps is easier than the Centrifugal and also it doesn't limit the movement capability of CHF patients thanks to smaller sizes. Moreover, it can work with smaller and lighter batteries thanks to less power requirement than centrifugal pumps as a result of rotor and blade geometries. Axial-flow pumps provide more advantages thanks to smaller size, lighter weight and less energy requirement than the other pump types, additionally to recovering physical needs of human body that can't be supplied because of insufficient heart functions.

At the present, design methods of diffuser and flow straightener are common for all axial-flow heart pump, even though their blade angles and amounts change.

However, in rotor component design, there are two different currently applied installation methods for permanent magnets of Brushless DC motor. First method is installing permanent magnets in to the external surface of rotor component and second one is loading them inside of blades located on rotor block. Although the first method is cheaper than the second one, magnetic flux losses are higher; because blades on the rotor surface require tolerance thickness in order to sufficiently transfer energy to blood. So, thickness of blades limits the reducing distance between permanent magnets located in rotor and coils located in pump housing (stator). Therefore, magnetic flux originated by permanent magnets reaches coils in stator with more loss that can't be reduced because of required blade thickness (also described as exterior flow channel thickness or fluid gap in literature). As a result, it limits the efficiency of motor and transferred kinetic energy to blood because of decreased rotational velocity of rotor and blades unless input power wasn't increased. In order to compensate this disadvantage, magnetic flux losses are reduced thanks to loading rotor block closer to the pump housing (stator) by decreasing blood flow channel thickness and blade thickness. However, this time transferred energy to blood is decreased because of less blade area and hereby, blood pumping volume is decreased. Consequently, the efficacy of this currently applied method is very low.

In the second currently applied method of installation of permanent magnets, they are loaded in to the blades on rotor. Although its more expensive and harder than first method, it reduces the loss of permanent magnet fluxes by reducing the distance between magnets and stator (pump housing). However, installation of permanent magnets in to the blades that have less available volume for magnet installation than the rotor block, causes to decrease on total volume of permanent magnets. It is known that the magnetic flux production by permanent magnets is directly proportional to its volume. So, low magnetic flux caused by decrease on magnet volume, decreases motor performance and transferred energy to blood by reducing rotational velocity. As a result, although this method allows flexible blade thickness for sufficiently transferring energy to blood limited by first installation method, second method requires more motor input power to increase rotational velocity for pumping blood sufficiently. Moreover, increased power demand reduces battery life. Consequently, the efficacy of second currently applied method is also very low.

In currently used artificial heart pumps, magnetic bearings (via magnets) or mechanical bearings (via roller bearings and shaft) are used to support and stabilize the rotor block in the pump housing (stator).

When shaft is used in order to stabilize rotor block in pump housing; shaft is located on the center of the rotor block and it is combined to the rotor block. Shortly, shaft is combined part of the rotor block. Generally, one tip of shaft and the other tip of it are assembled on the roller bearings namely mechanical bearings located inside of the hole (housing) at the center of diffuser and flow straightener. Shortly, diffuser and flow straightener provide stabilization of rotor block by supporting shaft tips that are combined to rotor. These mechanic bearings that contact with shaft tips during rotational motion, can be made from materials such as ceramic to reduce friction and overheating caused by friction. Also, the friction between two surfaces (shaft and mechanic bearing) can be reduced by using blood as lubricant fluid in some current designs. Moreover, rotation of shaft on mechanic bearings can be provided with less friction via loading permanent magnets to mechanical bearing locations. However, this method covers mechanical and magnetic bearings method together for levitation of rotor. Furthermore, extra permanent magnets can be installed on bearings (central housing of diffuser and flow straightener) in order to damp the axial thrust (back reactive axial force) of rotor that is caused by backward force on blades during acceleration of blood particles. However, corrosion can occur on the cover material of mechanical bearings, when mechanical bearings are used to support rotor. As a result, corrosion increases the maintenance need of device and limits the usage period of it. With these conditions, the best way is minimizing the friction force exerted by shaft that is combined to rotor component. So, magnetic bearings are used to levitate rotor block in pump housing without any friction by removing contact with any surfaces.

When magnetic bearings are used to support rotor instead of using mechanical bearings and shaft, permanent magnet couples with similar polarity are installed on rotor block surface and opposite side of this location at the interior wall of pump housing. Thereby, created magnetic field via interaction of these magnet couples, provide contactless rotation of rotor by levitating it. However, these extra magnet couples cause the increase on size and weight of rotor block. As a result, it negatively affects the weight and size of axial-flow pump in terms of implanting to body and portability by CHF patients.

As a result, disability of current solutions and disadvantages of current axial- flow heart pumps require development on concerned technical field and presence of new heart pump that eliminates these facts.

BRIEF DESCRIPTION OF PRESENT INVENTION

The present invention is related to artificial heart pump that provides almost all requirements and removes almost all disadvantages explained above and brings additional advantages. According to the literature search on concerned technical field, The present invention aims providing sufficient blood flow for human circulation system from Left Ventricle (LV) of heart to the aorta up to 15 Liter per minute volumetric flow under 6( 20 mmHg head pressure for adults.

The present invention aims preventing high hemolysis in order not to damage human physiology by providing better interaction between blade sets and blood particles via especially designed geometries of exterior (first blade set) and interior (second blade set) rotor blades.

The present invention aims, solving permanent magnet installation problem and hereby preventing decrease on motor efficiency.

The present invention aims creating alternative blood flow channel (interior channel) that is coaxial and parallel to the other blood flow channel (main channel or exterior) that is located between exterior surface of rotor block and interior surface of pump housing, by creating hole at inside of rotor block via extrusion of rotor and loading extra blade group (interior blades) in the hole created by this extruded cylindrical rotor.

The present invention aims increasing pumping volume of heart pump thanks to larger volume capacity of rotor block for containing blood as a result of alternative blood flow channel (interior channel) that is created via extrusion of rotor block.

The present invention aims recovering the decrease of pumping volume - that occurs as a result of narrowing blood flow channel at exterior of rotor (main flow channel) to increase motor performance with decreased magnetic flux loses - thanks to increase on pumping volume via alternative blood flow channel (interior channel) that located in extruded rotor.

The present invention aims providing flexibility on geometry of exterior flow channel (main flow channel) as a result of increase on pumping volume capacity of heart pump thanks to alternative blood flow channel. As a result of provided geometric flexibilities on exterior channel (main channel) and exterior blades, present invention aims minimizing the distance between permanent magnets located in rotor and stator coils located in pump housing in order to reduce magnetic flux losses. The present invention aims increasing motor efficiency as a result of minimized gap between rotor and pump housing.

The present invention aims preventing the limitation of installed permanent magnet volume by loading them to the rotor block surface at the opposite side of the stator coils by filling all closed surface.

The present invention aims achieving longer battery life with reduced demand of power that supplied by battery as a result of rising motor efficiency thanks to specially designed geometry of rotor that minimizes magnetic flux losses.

The present invention aims supplying same pump performance (head pressure-flow characteristic) as currently used heart pumps by using smaller size and lighter batteries as a result of decreased power demand.

The present invention aims providing portability for patients thanks to designing heart pump with smaller sizes and using smaller size and lighter batteries.

The present invention aims equalizing the velocity and pressure level of blood flow at exterior of rotor (main blood flow channel) to the velocity and pressure level of blood flow at inside of rotor (alternative blood flow channel) via blades located at exterior surface of rotor when blood flow outs from both channels.

The present invention aims reducing the manufacturing cost of device by installing permanent magnets in to the rotor surface instead of inside the exterior blades.

All structural and characteristic specifications of invention and all advantages of it, will be clearly understood with figures at below and detailed explanations about these figures; so all evaluations should be done by considering all these figures and detailed explanations. BRIEF EXPLANATION OF FIGURES

The structures of present invention should be evaluated by considering figures at below and explanations about figures to understand all additional components and advantages of invention well.

Figure 1 ; schematic section view of axial-flow heart pump that is subject of present invention,

Figure 2; schematic top view of rotor block,

Figure 3; schematic perspective view of rotor block,

Figure 4; schematic front side view of rotor block,

Figure 5; schematic perspective view of axial-flow heart pump components that assembled,

Figure 6; schematic perspective view of axial-flow heart pump without pump housing component,

Figure 7; Axial-flow heart pump schematic view from inlet side (where blood flow enters),

Figure 8; Axial-flow heart pump's schematic view from outlet side (where blood flow leaves).

REFERENCE NUMBERS

1. Axial-Flow Heart Pump

2. Pump Housing

3. Stator Coils

4. Position sensors

5. Diffuser

6. Exterior blades

7. Rotor

8. Interior blades

9. Flow straightener

10. Shaft 11. Main blood flow channel

12. Alternative blood flow channel

13. Permanent magnets

DETAILED EXPLANATION OF PRESENT INVENTION

In this section, present invention which is axial-flow heart pump (1), will be explained by showing it as an example for more clearly understanding and present invention can't be restricted with these detailed explanations.

Present axial-flow heart pump (1) shown in Figure 1, contains pump housing (2) ,flow straightener (9), diffuser (5) , rotor (7) and components that are contained by pump housing (2) as stator coils (3) and position sensors (4). Specialty of explained axial-flow heart pump (1) is containing electro-magnetic motor mechanism to rotate exterior and interior blades (6, 8) that provide blood flow by accelerating and pressurizing blood- via permanent magnets (13) that are located in rotor (7).

Present axial-flow heart pump (1) was designed in order to supply up to 15 liters per minute blood flow to Aorta as required by body, under 60-120 mmHg head pressure for an adult. Developed axial-flow heart pump (1), is known as Left- Ventricular Assist Device (LVAD) in the terminology, because generally it provides blood flow from Left Ventricle (LV) of Heart to the Aorta. Blood flow feed that is required by Aorta is also known as Cardiac Output in terminology.

The geometric structures of exterior and interior blades (6 , 8) were especially designed with their amounts in order to provide desired blood flow level and prevent high hemolysis in order not to damage human physiology. Moreover, brushless DC motor that basicly consists of permanent magnets (13) located in rotor (7) and stator coils (3) located in pump housing (2), were designed to rotate rotor (7) that includes interior and exterior blades (8 , 6) sets.

Specialty of present axial-flow heart pump (1) is providing advantages for decreased motor efficiency problem that originates in currently used heart pumps as a result of magnetic flux losses and less magnet volume because of rotor geometric structure. Its known that interior and exterior blades (6 , 8) sets of rotor (7) should have enough area in order to transfer energy to blood sufficiently; so interior and exterior blades (6 , 8) sets should have enough thickness. So, in the pumps that are similar with present axial-flow heart pump (1), tolerance distance between rotor (7) and pump housing (2) are required in order to load exterior blades (6) with enough thickness for sufficiently transferring energy. This tolerance distance is equal to the main flow channel (11) thickness in figure 1. However, this thickness namely blood gap causes loss of magnetic flux produced by permanent magnets (13), because it resists as a non-magnetic barrier between permanent magnets (13) located in rotor (7) and stator coils (3) located in pump housing (2). As a result, efficiency of motor decreases because of magnetic fluxes losses. Consequently, permanent magnets (13) should be loaded closer to the pump housing (2) by minimizing this gap in order to reduce magnetic flux losses for increasing motor efficiency; however this minimization method limits the exterior blades (6) thickness and main blood flow channel (11) width. As a detail, fluid gap and/or main blood flow channel (11) thickness can be used in text instead of distance between rotor (7) and pump housing (2).

Present invention that is axial-flow heart pump (1) solved this problem by minimizing tolerance distance that is required for exterior blades (6) as a result of decreasing need for the exterior blades (6) in order to transfer sufficient energy to blood thanks to creating coaxial alternative blood flow channel (12) by extruding inside of rotor (7) and loading extra interior and exterior blades (8 , 6) sets in here.

On the other hand, alternative blood flow channel (12) that is coaxial and parallel to the main blood flow channel (11) located between rotor (7) and pump housing (2), was created in the rotor (7) via extruding inside of rotor (7). Moreover, extra interior blades (8) set was loaded in this channel (12) that is located in extruded rotor (7). Thereby, pumping volume of axial-flow heart pump was increased thanks to alternative blood flow channel (12) that is created as coaxial and alternative to the main flow channel (11). Furthermore, possible decrease on pumping volume that can occur as a result of minimizing gap, main blood flow channel (11) thickness between permanent magnets (13) in rotor (7) and stator coils (3) in pump housing (2) for decreasing magnetic flux loses, was recovered via creating alternative blood flow channel (12) that provides extra pumping volume. Hereby, flexible options was provided on the geometric design of rotor (7) by eliminating the negative effect of main blood flow channel (11) geometric design on the flow capacity of axial-flow heart pump (1) thanks to alternative blood flow channel (12). Furthermore, interior blade (8) set increased total blade area of rotor (7). So, interior blades (8) compensated the decreased energy transfer that is caused by reducing the thickness of exterior blades (6) to minimize the thickness of main blood flow channel (11) for increment on motor efficiency. Hereby, flexible options on exterior blade (6) geometry were provided by increasing total blade area thanks to interior blades (8). As a result of these flexible options on geometric design of rotor (7) and exterior blades (6), losses of magnetic flux that originated by permanent magnets (13) were minimized by reducing the distance between permanent magnets (13) of brushless DC motor and stator coils (3) in pump housing (2). Moreover, volume of permanent magnets (13) was increased by installing them to the rotor block (7) instead of loading them into the exterior blades (6).

Hereby, increment on motor efficiency was provided by increasing magnetic flux thanks to increase on volume of permanent magnets (13) and reducing flux loses thanks to narrowing main blood flow channel (11) thickness. Moreover, battery life was extended via dragging less current from power source thanks to decreased energy demand as a result of increased motor efficiency. Furthermore, reduced energy demand allows smaller size and lighter battery option for achieving same performance as currently used heart pumps. So, it provides portability for patients who will carry present axial-flow heart pump (1).

As shown in Figure 2, the pumping volume of axial-flow heart pump (1) was increased by providing extra volumes for blood as a result of creating alternative blood flow channel (12) by extruding rotor (7). Also, loaded interior blade (8) set in alternative blood flow channel (12) increased total blade area in order to transfer sufficient energy to blood. Increased volume of pumping and total blade area reduced required rotational velocity in order to transfer sufficient energy to blood. Hereby, hemolysis that occurs because of contact with interior and exterior blade (6 , 8) sets and blood particles during their rotational motion, was reduced.

As shown in figures 3 and 4, exterior blades (6) were loaded on the rotor (7) exterior surface in order to equalize the pressure and velocity level of blood that flows through main blood flow channel (11) with blood that flows through alternative blood flow channel (12).

As shown in figures 3 and 4, high manufacturing cost of installing permanent magnets (13) in to the exterior blades (6) located on rotor (7) was eliminated thanks to installing them into the rotor (7) instead of exterior blades (6).

As shown in figure 5, axial-flow heart pump (1) recovers the blood flow that is insufficient for circulation system as a result of dysfunction of heart, by providing blood flow as helping to heart as being implanted between Left Ventricle of Heart and Aorta Artery.

The function theory of present axial-flow heart pump (1) is transferring rotational motion energy imparted by Brushless DC motor to blood as potential and kinetic energy via contact between blood and exterior blade (6) sets and interior blades (8) to pressurize blood and accelerate it for providing sufficient blood flow demanded by patient. In axial-flow heart pump (1), brushless DC motor was used in order to provide rotation of interior and exterior blade (8 , 6) sets. Brushless DC motor is electro-magnetic mechanism that contains stator coils (3) in stator component and permanent magnets (13) in rotor (7) component and provides rotational force and motion via magnetic flux that originates from these magnets (13). Also, position sensors (4) that trigger stator coils (3) by sending signal in terms of rotor (7) angular position via its encoder, was used in order to provide 360 degree synchronized rotation of rotor (7).

As shown in figure 5, blood flow passes through inside of pump housing (2). The inner surface of explained pump housing (2) contacts with blood, so it was made from a material that doesn't react with blood such as titanium.

In the axial-flow heart pump (1) that is shown in figure 6, blood flows from left to right direction. Blood flow that comes from left side, enters to the axial-flow heart pump (1) at flow straightener (9) section. Explained flow straightener (9) is the first component of axial-flow heart pump (1) that blood contacts and its function is regulating blood flow directions for better contact with next rotor (7) component by parallelizing blood flow directions to its flow straightener (9). Explained axial-flow heart pump's (1) flow straightener (9) component is one of the stationary part of invention by being combined to the pump housing (2). So, it doesn't rotate with the rotor (7) and its interior and exterior blades (8 , 6). Moreover, flow straightener (9) supports horizontal stabilization of rotor (7) during rotation without contact between rotor (7) and pump housing (2) via mechanical bearings or magnetic bearings at center hole in it (9).

The blood flow that passes through flow straightener (9), enters the rotor (7). Blood flow splits up two ways at inlet of two channel (11 and 12) intersections. The first way passes through main blood flow channel (11) at exterior of rotor (7) and second way passes through alternative blood flow channel (12) inside of the rotor (7). Acceleration of the blood flow through main blood flow channel (11) was provided by exterior blades (6) that are located on exterior of rotor (7). Also, acceleration of the blood flow through alternative blood flow channel (12) in rotor (7) was provided by interior blades (8) located inside of rotor (7). Exterior and interior blades (6 , 8) were designed with suitable angles (attack and trailing angles) in order to equalize the pressure and velocity level of blood that flows through main blood flow channel (11) and alternative blood flow channel (12) ,when it exits from both channel, in other words where both flow combines.

Explained rotor (7), contains permanent magnets (13) that are located in its main body. Explained permanent magnets (13) produce magnetic flux and these fluxes flow through stator coils (3). Interaction of these fluxes with stator coils (3) provides rotational motion of rotor (7) component that includes exterior and interior blades (6 , 8). Shortly, permanent magnets (13) - located in rotor (7) that contains exterior and interior blades (6 , 8) of axial-flow heart pump (1)- and stator coils (3)- that are loaded on stationary component (pump housing (2)) of axial-flow heart pump (1) (LVAD)- are two components of Brushless DC motor. Moreover, shaft (10) was installed and combined into the center of rotor (7) block in order to support rotational motion and stabilize it without any contact with pump housing (2). One tip of shaft (10) was loaded on the mechanical bearings in hole at the center of flow straightener (9) that is combined to the pump housing (2) and the other tip of shaft (10) was loaded on the mechanical bearings in hole at center of diffuser (5) that is combined to the pump housing (2). So, rotor (7) was installed to axial-flow heart pump (1) thanks to stationary components of axial-flow heart pump (1) as diffuser (5) and flow straightener (9) that support rotational motion of rotor (7) and stabilize it without any divergence from horizontal axes.

As shown in figure 7, blood flow in the axial-flow heart pump (1 ) enters the diffuser (5) blades section after it exits from main and alternative blood flow channels (11 , 12). Explained diffuser (5) component is stationary part of axial-flow heart pump (1) by being combined to the pump housing (2). So, it doesn't rotate with the rotor (7) and its exterior and interior blades (6 , 8) sets .Blood flow that gains velocity and pressure via the exterior and interior blades (6 , 8) has velocity vectors that are tangential and parallel to the pump housing (2) inner surface at outlet of rotor (7). So, diffuser (5) blades convert these velocity vectors to parallel vectors to pump housing surface. During this conversion, blood flow gets slower namely it loses its kinetic energy. Thereby, pressure of blood increases at exit of axial-flow heart pump (1) by converting kinetic energy of blood that is gained via rotational motion of rotor (7) to potential energy as namely head pressure. Diffuser (5) blades should be designed in terms of the numbers of blades and blade angles (attack and trailing angle) for efficient energy conversion. Moreover, diffuser (5) supports rotor (7) and stabilizes it to not contact with pump housing (2) via mechanical bearings or magnetic bearings in hole at center of diffuser (5). In the other optional design of present invention, axial-flow heart pump (1) were manufactured by adding magnetic bearings in order to support rotor (7) block and levitate it in pump housing (2) without any divergence from axes during its rotational motion, instead of using shaft (10) combined into the rotor (7) block and mechanical bearings that are located in holes at center of diffuser (5) and flow straightener (9).

In these optional designs, permanent magnet couples with same polarity were loaded to inner surface of pump housing (2) so as not to contact with rotor (7) block and on the rotor (7) block surface that is opposite side of first magnet couple locations in pump housing (2). These two magnet couples are installed in order to provide interaction with each of them. Rotor (7) block was levitated on rotation axes without any contact with pump housing (2) via magnetic field that is created by interaction of two permanent magnet couples.

In the other optional application of present invention, invention can be used for creating blood flow in the other regions of body instead of canalizing from heart. Also, it can be used in order to provide blood flow from Right Ventricle to Pulmonary arteries, between two arteries by bypassing a blockage or between one artery and more than one vein.

The scope and essence of the invention is described above. It obviously seems, based on the descriptions above and the attached figures, a person skilled in the art and techniques will be able to use similar techniques to develop similar invention and/or apply these techniques to other fields that have similar purposes with concerned field. So, it is apparent that this kind of technique is missing from any criteria for innovation and development on present technique, especially under the presence of our application. Protection content of this application was determined in claims section and it cannot definitely be restricted with explanations above that are reported as an example.

Claims

1. Present invention is an axial-flow heart pump (1) that supports circulation system and provides blood flow at location where it (1) is implanted in body by pumping blood from inlet to outlet and contains pump housing (2), flow straightener (9) and diffuser (5) for regulating blood flow, shaft (10) and/or magnetic bearings to stabilize rotational motion and damps axial thrust, components of brushless DC motor as stator coils (3) and position sensors (4) that provides feedback signal for stator coils (3) is characterized by containing;

- rotor (7) that is formed as extruded cylinder, which splits blood flow which comes from flow straightener (9) to two sections as main blood flow channel (11) located at exterior surface of it (7) and alternative blood flow channel (12) located inside of it (7) and sends blood flow to diffuser (5),

- permanent magnets (13) that are installed in rotor (7).

2. The axial-flow heart pump (1) according to claim 1, characterized by containing, alternative blood flow channel (12) that is created inside of extruded rotor (7) as being additional and alternative to the main blood flow channel (11) which is located between said rotor (7) and pump housing (2), is located as co-axial and/or parallel to the said main blood flow channel (11), has blood flow that comes from flow straightener (9) and flows to the diffuser (5) and compensates decrease on blood flow occurs as a result of minimizing thickness of main blood flow channel (11), by increasing pumping volume of axial-flow heart pump (1).

3. The axial-flow heart pump (1) according to claim 1, characterized by containing, main blood flow channel (11) that is located between said rotor (7) and pump housing (2), provides minimized magnetic flux losses that originate from permanent magnets (13) thanks to reducing the distance between said rotor (7) and pump housing (2) in order to increase electro-magnetic motor performance and has blood flow that comes from flow straightener (9) and flows to the diffuser (5).

4. The axial-flow heart pump (1) according to claim 1, characterized by containing, one or more than one interior blades (8) that is/are located in alternative blood flow channel (12) created in said rotor (7) and direct(s) blood flow that comes from flow straightener (9) and passes through alternative blood flow channel (12), to diffuser (5) by accelerating and pressurizing it. The axial-flow heart pump (1) according to claim 1 , one or more than one exterior blades (6) that is/are located on rotor (7) as namely main blood flow channel (11) and direct(s) blood flow that comes from flow straightener (9) and passes through main blood flow channel (11), to diffuser (5) by accelerating and pressurizing it.