Classifications

• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
  • H01F1/00—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties
  • H01F1/44—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of magnetic liquids, e.g. ferrofluids
  • H01F1/442—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of magnetic liquids, e.g. ferrofluids the magnetic component being a metal or alloy, e.g. Fe
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
  • A61M60/00—Blood pumps; Devices for mechanical circulatory actuation; Balloon pumps for circulatory assistance
  • A61M60/10—Location thereof with respect to the patient's body
  • A61M60/122—Implantable pumps or pumping devices, i.e. the blood being pumped inside the patient's body
  • A61M60/165—Implantable pumps or pumping devices, i.e. the blood being pumped inside the patient's body implantable in, on, or around the heart
  • A61M60/178—Implantable pumps or pumping devices, i.e. the blood being pumped inside the patient's body implantable in, on, or around the heart drawing blood from a ventricle and returning the blood to the arterial system via a cannula external to the ventricle, e.g. left or right ventricular assist devices
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
  • A61M60/00—Blood pumps; Devices for mechanical circulatory actuation; Balloon pumps for circulatory assistance
  • A61M60/10—Location thereof with respect to the patient's body
  • A61M60/122—Implantable pumps or pumping devices, i.e. the blood being pumped inside the patient's body
  • A61M60/196—Implantable pumps or pumping devices, i.e. the blood being pumped inside the patient's body replacing the entire heart, e.g. total artificial hearts [TAH]
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
  • A61M60/00—Blood pumps; Devices for mechanical circulatory actuation; Balloon pumps for circulatory assistance
  • A61M60/40—Details relating to driving
  • A61M60/424—Details relating to driving for positive displacement blood pumps
  • A61M60/427—Details relating to driving for positive displacement blood pumps the force acting on the blood contacting member being hydraulic or pneumatic
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
  • A61M60/00—Blood pumps; Devices for mechanical circulatory actuation; Balloon pumps for circulatory assistance
  • A61M60/10—Location thereof with respect to the patient's body
  • A61M60/122—Implantable pumps or pumping devices, i.e. the blood being pumped inside the patient's body
  • A61M60/126—Implantable pumps or pumping devices, i.e. the blood being pumped inside the patient's body implantable via, into, inside, in line, branching on, or around a blood vessel
  • A61M60/148—Implantable pumps or pumping devices, i.e. the blood being pumped inside the patient's body implantable via, into, inside, in line, branching on, or around a blood vessel in line with a blood vessel using resection or like techniques, e.g. permanent endovascular heart assist devices
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
  • A61M60/00—Blood pumps; Devices for mechanical circulatory actuation; Balloon pumps for circulatory assistance
  • A61M60/80—Constructional details other than related to driving
  • A61M60/855—Constructional details other than related to driving of implantable pumps or pumping devices
  • A61M60/89—Valves
  • A61M60/892—Active valves, i.e. actuated by an external force

Definitions

• Magnetic fluid-assisted electromagnetic drive for a blood pump to support or to partially or completely replace the heart
• the invention is based on a magnetofluid-assisted electromagnetic drive for a blood pump for support or for partial or total replacement of the heart, which consists of one or more electromagnets and force-converting devices, as is known from US Pat. No. 4,650,485 .
• Electromagnetic Table systems consist of an electromagnet that mechanically squeezes a blood sack to promote the blood. Such an arrangement is described in detail in U.S. Patent 3,874,002. With the help of an electric motor, electromechanical systems generate a rotational movement which is converted into a pump movement. Electrohydraulic and electropneumatic systems are also known, in which a liquid or a gas is pumped into a chamber by means of a hydraulic pump or a compressor in order to move a flexible membrane for conveying the blood.
• Magnetofluids are stable dispersions with super-magnetic properties. They consist of single domain particles which are homogeneously distributed in selectable solvents with the aid of surface-active substances. The homogeneous distribution is maintained even in a strong magnetic field (gradient).
• the DD description 160532 describes such a magnetic fluid in detail. Magnetofluids with initial permeabilities up to 4 and saturation magnetizations up to 100 mT are known and described.
• the invention has for its object to provide a drive for a blood pump to support or to partially or completely replace the heart, the blood pump largely corresponds to the natural heart in terms of its weight and its energy density, and is particularly suitable for implantation, a reduction in the size of the overall system compared to known systems while improving the efficiency is made possible.
• a blood pump has a magnetofluid-assisted electromagnetic drive, which consists of one or more electromagnets and force-converting devices and in which the interspace of at least one electromagnetic circuit is completely or partially filled with magnetofluid, the poles having permanent magnetic properties .
• the essential idea of the invention is that the effect of the intermediate space is increased by the introduced magnetic fluid (ferrofluid, magnetic fluid) because of its higher permeability. This succeeds because the transition from the highly permeable inference to the fluid is one Force increase (Maxwellian tension).
• the negative pressure of the magnetic fluid can be used, which arises from the fact that on its free surface (for example to air), under the action of a magnetic field, force densities arise which are directed out of the magnetic fluid.
• the simplest version of the drive can be placed directly on a blood pump as a unicameral system. In more complex designs, two-chamber or four-chamber training is also possible. Executions in series are just as possible as a parallel arrangement.
• the drive can therefore be used in simple cardiovascular supports or can be used as a partial or even total replacement of the heart in a natural reproduction of the heart function.
• Fig. 1 cross section of the artificial heart drive when compressed
• Chamber, 2 cross section of the artificial heart drive during the suction process
• Figure 1 the principle of the drive is shown schematically for a single-chamber system in section.
• the chamber volume 10 is tightly enclosed by the chamber wall 9.
• the chamber wall 9 is designed as a flexible membrane and has inflow and outflow pipes 11 together with the ventricle 12.
• the flexibility of the chamber wall 9 allows the chamber volume 10 to be compressed by the drive 1 to 6.
• the necessary power transmission is through the direct contact of the upper chamber wall 9 with the guaranteed lower core half 2.
• the stationary parts are fixed by the housing 8, which is connected on the one hand to the lower chamber wall 9 and on the other hand to the upper core half 1.
• the two core halves 1 and 2 close in that the magnetic fluid 5 escapes from the magnetorheological contraction space.
• the springs 4 are tensioned for the expulsion phase.
• the chamber volume 9 is enlarged due to the elastic forces of the chamber wall 9 and, associated with this, as shown in FIG. 2, a suction process takes place via the opened inlet ventricle 12.
• the coils are fed from the outside through feed lines running in the channel 14.
• the specially developed magnetofluids with a saturation magnetization of 120 to 450 mT and initial permeabilities of 5 to 25 are advantageously used.
• These very high values for magnetofluids are achieved by using new magnetofluid compositions which contain ferromagnetic single domain particles (iron, cobalt or iron-cobalt alloys) in high concentration and which are used in low-viscosity solvents. agents are homogeneously distributed by means of surface-active compounds which are firmly anchored to the particle surface and are readily soluble in the respective solvent.

Landscapes

• Health & Medical Sciences (AREA)
• Engineering & Computer Science (AREA)
• Heart & Thoracic Surgery (AREA)
• Cardiology (AREA)
• Life Sciences & Earth Sciences (AREA)
• Anesthesiology (AREA)
• Biomedical Technology (AREA)
• Hematology (AREA)
• Mechanical Engineering (AREA)
• Animal Behavior & Ethology (AREA)
• General Health & Medical Sciences (AREA)
• Public Health (AREA)
• Veterinary Medicine (AREA)
• Power Engineering (AREA)
• External Artificial Organs (AREA)
• Prostheses (AREA)
• Soft Magnetic Materials (AREA)

Applications Claiming Priority (3)

Publications (1)

Family

ID=7787799

Family Applications (1)

Country Status (10)

Families Citing this family (18)

Family Cites Families (14)

• 1996
  • 1996-02-27 DE DE19654864A patent/DE19654864A1/de not_active Ceased
• 1997
  • 1997-02-27 WO PCT/DE1997/000441 patent/WO1997031662A1/de not_active Application Discontinuation
  • 1997-02-27 US US08/945,780 patent/US6074365A/en not_active Expired - Fee Related
  • 1997-02-27 HU HU9901479A patent/HUP9901479A3/hu unknown
  • 1997-02-27 AU AU26317/97A patent/AU719915B2/en not_active Ceased
  • 1997-02-27 BR BR9702122A patent/BR9702122A/pt not_active Application Discontinuation
  • 1997-02-27 JP JP9530518A patent/JPH11504554A/ja active Pending
  • 1997-02-27 CA CA002219490A patent/CA2219490A1/en not_active Withdrawn
  • 1997-02-27 EP EP97918007A patent/EP0822840A1/de not_active Withdrawn
  • 1997-02-27 EA EA199700273A patent/EA000221B1/ru not_active IP Right Cessation

Non-Patent Citations (1)

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