|Publication number||US3608088 A|
|Publication date||28 Sep 1971|
|Filing date||17 Apr 1969|
|Priority date||17 Apr 1969|
|Publication number||US 3608088 A, US 3608088A, US-A-3608088, US3608088 A, US3608088A|
|Inventors||Bernstein Eugene F, Blackshear Perry L, Dorman Frank D|
|Original Assignee||Univ Minnesota|
|Export Citation||BiBTeX, EndNote, RefMan|
|Referenced by (88), Classifications (18)|
|External Links: USPTO, USPTO Assignment, Espacenet|
se t. 28 1971 ETAL P F. D. DQRMAN IMPLANTABLE BLOOD PUMP Filed April 17, 1969 3 Sheets-Shoat 1 IIIII Sept. 28, F. D. DQRMAN ETAL v v IMPLANTABLE BLOOD PUMP Filed April 17. 1969 3 Shoets-$heot a se t. 28 1971' A IMPLANTABLE BLOOD PUMP Filed April 17, 1969 3 Sheets-Sheot 5 United States Patent Ofice Patented Sept. 28, 1971 3,608,088 IMPLANTABLE BLOOD PUMP Frank D. Dorman, St. Paul, Eugene F. Bernstein, Minneapolis, and Perry L. Blackshear, Mahtomedi, Minn., assignors to The Regents of the University of Minnesota, Minneapolis, Minn.
Filed Apr. 17, 1969, Ser. No. 816,952 Int. Cl. A61f 1/24; F04b 17/00, 35/04 US. C]. 31
ABSTRACT OF THE DISCLOSURE A centrifugal blood pump and method of pumping blood to provide assistance to a failing heart. The pump is intended to be implanted and is provided with a magnetic drive system which permits a synchronous magnetic coupling with an outside power unit with no wires or tubes through the skin. The pump has but a single moving part. It is lubricated by the pumped blood and provides an indefinite lifetime of service-free performance.
The invention described herein was made in the course of work under a grant or award from the Department of Health, Education and Welfare.
This invention isdirected to a centrifugal magnetically driven blood pump designed to be used as a cardiac assist device, and the method of using the same. Although the primary purpose of the pump of the present invention is as an implanted assist to or replacement for a failing heart in a living body, it can also be used as a blood pump for open heart surgery where bypass of the heart is needed. To allow complete implantation with no wires or tubes through the skin, a magnetic drive system is utilized which is operated from a magnetic or electromagnetic energy source outside of the body.
The invention is illustrated in the accompanying drawings in which the same numerals identify corresponding parts and in which:
FIG. 1 is a section on a plane passing through the longitudinal axis (the axis of rotation) of the pump;
FIG. 2 is a transverse section on the line 22 of FIG. 1 and in the direction of the arrows;
FIG. 3 is a transverse section on the line 33 of FIG. 1 and in the direction of the arrows;
FIG. 4 is a transverse section on a reduced scale on the line 4-4 of FIG. 1 and in the direction of the arrows;
FIG. 5 is a schematic representation showing the pump of the present invention implanted within the body and coupled through the skin with an external power unit;
FIG. 6 is an end elevation partially in fragmentary transverse section similar to FIG. 2 and showing a modified form of blood pump providing pulsatile flow; and
FIG. 7 is a section on the line 7--7 of FIG. 6 and in the direction of the arrows.
Referring now to the drawings, the pump according to the present invention includes a cylindrical pump housing, indicated generally at 10, having a cylindrical tubular wall 11 and a transverse annular flange 12 extending inwardly from the inside surface of wall 11 intermediate of the ends of housing 10. A pump casing, indicated generally at 13, is inserted partially within the housing 10. The pump casing 13 includes an inlet tube 14 coaxial with the longitudinal axis of the pump and communicating through a slightly choked orifice 15 with a scroll impeller housing 16 from which a tangential downstream diffuser tube 17 provides a discharge outlet. The pump casing 13 is held in place within the pump housing 10 against one face of flange 12 by virtue of a cast inert lightweight fill material 18, such as epoxy resin or the like. 'Desirably the space between the pump housing and pump casing is 5 Claims substantially completely filled. The cast material is covered by an annular cover plate 19 fitted within one end of the pump housing and being secured to a sleeve 20 which fits around the outside of the blood entry tube 14.
The inside wall of the pump housing on the opposite side of flange 12 is threaded to receive an externally threaded rotor housing 21. Rotor housing 21 is generally cup-shaped and flat at its closed end. A rear thrust plate 22 is disposed against the inside bottom of the rotor housing and a front thrust plate 23 is disposed in the open end of the rotor housing pressed against the face of flange 12. An -O-ring 24 held in a V-shaped groove formed between the rotor housing and front thrust plate is compressed against flange 12 to form a seal. Rotor 25 is supported between the thrust plates 22 and 23.
Rotor 25 includes a high energy bar magnet 26 set in and secured in a transverse slot in the rear face of the rotor 25 so as to form a flush fit and uninterrupted surface. The rotor shaft 27 extends through a central opening in the front thrust plate 23, the forward face of which is concave and serves to complete the scroll impeller housing. An impeller, indicated generally at 29, is disposed within the scroll chamber. Impeller 29 includes a conical hub 30 supporting a plurality of radially extending blades 31. The impeller blades 31 are generally in the form of isosceles trapezoids secured at one end of their bases to hub 30. Hub 30 has a threaded shank 32 which is received in the rotor shank. The threads of shank 32 are opposite in direction from the direction of rotation of the rotor such that accidental detachment of the impeller from the rotor by unscrewing of the shank is made impossible. I
Plates 22 and 23 function as fluid dynamic thrust and journal bearings that are lubricated with blood for support of the pump rotor. As best seen in FIG. 3, the inward faces of the thrust plates are provided with a plurality of radial channels 33 each of which communicates with an arcuate channel 34 of lesser depth for maintaining the parallel flat faces of the rotor lubricated with blood. The face of thrust plate 22 is a mirror image of that of plate 23, as shown in FIG. 3.
The pump is constructed of materials which are com patible with the body fluids with which'they come in contact when the pump is implanted. For example, the pump housing, thrust plates, rotor and impeller are desirably all formed from stainless steel. The pump casing is desirably formed by electro-deposition of nickel over a smooth gold-plated copper core, which is then dissolved to provide a smooth surfaced impeller chamber to minimize cell injury. The rotor housing is formed from a rigid material which is electrically non-conducting, such as polycarbonate resin or polypropylene or a ceramic material, such as alumina. The magnet is formed from a high energy magnetic iron-aluminum-nickel-cobalt-copper alloy material, such as that sold under the trade names Alnico VIII or Alnico IX. In some instances where economy of size is a critical factor, magnetic platinum-cobalt alloys may be used.
Referring to FIG. 5, there is shown schematically the manner in which the blood pump according to the present invention may be implanted, as for example in the chest cavity. Blood inflow to the pump is through a rigid cannula 35 into the left ventricular cavity to the inlet 14. Outflow is from the dilfuser 17 through a Dacron graft 36 to the descending thoracic aorta. In this manner the pump receives and discharges blood which otherwise would pass through the heart so as to reduce the flow of blood through the heart and reduce the pumping load otherwise put on the heart.
As shown, the pump is implanted with the outside transverse surface of the rotor housing 21 underlying the skin surface '37 and the axis of rotation substantially normal to the skin surface. The rotor 25 f the pump is driven from a drive magnet indicated schematically at 38'. The drive magnet is a high energy bar magnet similar to that of the pump rotor. It is desirably enclosed in a circular plate as in the pump rotor so as to minimize air drag. It is mounted to be rotated by a direct current motor 39 connected by conductor Wires 40 and 41 to a suitable power source 42, such as a small portable battery pack which is easily carried by the patient. The drive magnet is disposed immediately adjacent the skin surface in axial alignment with the pump rotor. Alternatively, the pump rotor may be driven by setting up a rotary electromagnetic field by means of suitable coils disposed adjacent the skin surface in alignment with the pump.
In use, the blood from tube 35 is slightly accelerated as it passes through the throat 15 into the scroll impeller chamber. The blood is pumped centrifugally by action of the impeller blades rotated at high speeds. The inverted venturi exit from the impeller chamber decelerates the blood flow before its return through tube 36.
Where pulsatile blood flow is considered to be desirable or necessary, the pump output pressure can be made to simulate the pressure pulsations of the natural heart by either of two methods: The drive unit 38-39 may be driven at changing speeds so as to cause the output pressure to change. The r.p.m. of the impeller controls the output pressure. Alternatively, as shown in FIGS. 6 and 7, the pump structure may be modified by the addition to the exit diffuser 17 of a fluid oscillator 43 to cause the blood flow to vary from efiicient recovery of kinetic energy (diffuser flow unseparated) to ineflicient recovery (diffuser flow separated) giving the desired pressure changes while maintaining the rotor speed constant. The
fluid oscillator 43 is in the form of a tube extending generally parallel to the diffuser 17 and communicating at one end with the mouth of the diffuser through a port 44 and at the opposite end with the narrow throat of the diffuser through a port 45.
The mode of operation of the fluid oscillator is as follows: Flow in the diffuser is established and full pressure recovery at the downstream port 44 of the oscillator makes the pressure at 44 higher than at the upstream port 45 and therefore accelerates fluid in oscillator 43. When the oscillator velocity at port 45 reaches some critical value the main ditflfuser flow separates and the pressure recovery at port 44 drops. The the flow in the oscillator 43 decelerates so that the oscillator velocity at port 44 falls below a critical value and diffuser flow will reattach. After a time lag the pressure at port 44- rises again and the process repeats. Time constants and pulse heights can be modified by changing the dimensions of the oscillator 43 and the size and locations of the ports 44 and 45.
Where the pump of the present invention is to be used as a total replacement for the heart it is provided with a second scroll chamber and impeller. The second chamber lies in parallel side-by-side relation with the first. The chambers are axially aligned, the impellers of both being driven from the same shaft. The innermost of the two chambers is provided with a radial or tangential inlet and tangential outlet. Since both impellers rotate at constant speed, variations in pressure to correspond to those of the heart are achieved by varying the sizes of the impellers and chambers.
The pump has been found to have a very low level of blood damage. The index of hemolysis has been determined to be 0.01 or lower. The pump is optimized in dimensions for the pressure head and flow rates needed, for example, about 100 mm. Hg pressure and 6 liters per minute flow. Byway of reference, the outside diameter of the pump housing is approximately two inches. The pressure-flow curves of the pump are such that the blood pressure can be set by controlling the pumpr.p.m. only. The pressure curve is flat to within ten percent over the range of body flow needed by the body. Typically, the pump is operated at about 4,000 r.p.m. plus or minus a few hundred. No electrical or mechanical feedback controls are needed. The pump need not be self-correcting. It runs at a constant speed which may be changed depending upon the Wishes of the doctor or patient in accord with the patients needs. The implanted pump has but a single moving contiguous assembly. The bearings are lubricated with the pumped fluid blood. So long as the pump is constructed from proper materials to prevent chemical attack, the pump has an indefinite lifetime. There is no wear on the rotor due to wall contact. The external drive motor and magnet or magnetic field unit can be serviced or quickly replaced without surgery.
The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:
1. A non-wear long-life constant speed centrifugal pump for implantation within a living body for pumping blood with minimum hemolysis, said pump comprising:
(A) a rigid housing of size permitting implantation within the thoracic cavity and of material compatible with body fluids,
(B) a scroll chamber within the housing, said chamber being smooth surfaced to minimize cell injury,
(C) an axial inlet to and tangential outlet from said chamber,
(D) impeller means journaled for rotation within said chamber for moving blood therethrough with low level of blood damage at substantially constant pressure at needed body flow rates,
(E) a second chamber within said housing for enclosing drive means,
(F) magnetic drive means within said second chamber for driving said impeller means, said drive means comprising a rotor journaled for rotation within the housing,
(1) said rotor and impeller being secured in axial alignment on a common shaft for rotation as a unit,
(2) said rotor including a magnet disposed transversely of the axis of rotation,
(3) said rotor being supported between a pair of fluid dynamic thrust and journal bearings,
(G) a channel interconnecting said pump chamber and drive means chamber,
(H) the surfaces of said rotor being closely spaced from the walls of said drive means chamber to maintain a thin liquid layer for lubrication of the bearings,
(I) at least the portion of the housing enclosing the drive means being electrically non-conductive, whereby the drive means may be driven at substantially constant speed by a mechanically unconnected external source of magnetic energy.
2. A blood pump according to claim 1 further characterized in that said magnet is a bar magnet composed of high energy magnetic alloy material and set in one face of said rotor.
3. A blood pump according to claim 1 further characterized in that:
(A) said axial inlet is provided with a choked orifice adjacent the pump chamber to accelerate blood flow into the impeller, and
(B) said tangential outlet is an inverted venturi to decelerate blood flow.
4. A blood pump according to claim 1 further characterized in that:
(A) power means are provided to drive said magnetic drive means,
(B) said power means comprising a source of a rotating magnetic field,
(C) said power means being spaced from and mechanically unconnected to said pump drive means, and
(D) said power means being disposed so that said magnetic field is in substantial axial alignment with said 5 pump drive means, whereby said power means is adapted to be placed externally of the living body to drive said pump with the body tissue interposed therebetween when said pump is implanted in the body.
5. A centrifugal blood pump comprising:
(A) a housing,
(B) a scroll pump chamber within the housing,
(C) an axial inlet to and tangential outlet from said scroll chamber,
(1) said axial inlet being provided with a choked orifice adjacent the pump chamber to accelerate blood flow into the chamber, and
(2) said tangential outlet being an inverted venturi to decelerate blood flow,
(D) pumping means within said chamber for moving blood therethrough comprising an impeller journaled for rotation in said chamber,
(E) means for providing pulsatile flow from said pump, said means comprising:
(1) a fluid oscillator tube extending longitudinally along said tangential outlet,
(2) a port in said outlet wall adjacent the exit from said scroll chamber communicating with one end of said fluid oscillator, and
(3) a further port in the wall of the outlet downstream from the first port and communicating with the opposite end of said fluid oscillator,
(F) a second chamber within said housing for enclosing drive means,
References Cited UNITED STATES PATENTS Saunders 4l7420 Nichols et a1 41520 6X Englesberg et al. 4l7420 Rafferty et a1. 1281X De Bennetot et al 31 OTHER REFERENCES The Use of a Magnetic Field to Remotely Power an Implantable Blood Pump, by B. K. Kusserow, Transactions American Society For Artificial Internal Organs, vol. VI, 1960, pp. 292-2961 RICHARD A. GAUDET, Primary Examiner R. L. FRINKS, Assistant Examiner US. Cl. X.R.
1281R; 3-Dig. 2; 415-204, 206; 4l7420, 423
|Citing Patent||Filing date||Publication date||Applicant||Title|
|US4105016 *||18 Nov 1976||8 Aug 1978||Donovan Jr Francis M||Heart pump|
|US4135253 *||30 Nov 1976||23 Jan 1979||Medtronic, Inc.||Centrifugal blood pump for cardiac assist|
|US4427470||1 Sep 1981||24 Jan 1984||University Of Utah||Vacuum molding technique for manufacturing a ventricular assist device|
|US4458366 *||6 Aug 1982||10 Jul 1984||Macgregor David C||Artificial implantable blood pump|
|US4473423||16 Sep 1983||25 Sep 1984||University Of Utah||Artificial heart valve made by vacuum forming technique|
|US4526510 *||7 Mar 1983||2 Jul 1985||Hoffman Joseph H||Double-walled centrifugal fan scroll and system of operation|
|US4584994 *||30 Sep 1983||29 Apr 1986||Charles Bamberger||Electromagnetic implant|
|US4589822 *||9 Jul 1984||20 May 1986||Mici Limited Partnership Iv||Centrifugal blood pump with impeller|
|US4606698 *||9 Jul 1984||19 Aug 1986||Mici Limited Partnership Iv||Centrifugal blood pump with tapered shaft seal|
|US4610658 *||21 Feb 1985||9 Sep 1986||Henry Buchwald||Automated peritoneovenous shunt|
|US4642036 *||17 Sep 1984||10 Feb 1987||Young Niels O||Magnet ball pump|
|US4643641 *||10 Sep 1984||17 Feb 1987||Mici Limited Partnership Iv||Method and apparatus for sterilization of a centrifugal pump|
|US4717311 *||9 Jul 1986||5 Jan 1988||Willette Russell J||Centrifugal pump|
|US4778445 *||28 Nov 1986||18 Oct 1988||Minnesota Mining And Manufacturing Company||Centrifugal blood pump with backflow detection|
|US4785515 *||9 Nov 1987||22 Nov 1988||Willette Russell J||Method of making a centrifugal pump|
|US4838889 *||23 Jul 1986||13 Jun 1989||University Of Utah Research Foundation||Ventricular assist device and method of manufacture|
|US4869642 *||9 Jun 1988||26 Sep 1989||Allied-Signal Inc.||Variable output vortex pump|
|US4898518 *||31 Aug 1988||6 Feb 1990||Minnesota Mining & Manufacturing Company||Shaft driven disposable centrifugal pump|
|US4927407 *||19 Jun 1989||22 May 1990||Regents Of The University Of Minnesota||Cardiac assist pump with steady rate supply of fluid lubricant|
|US5017103 *||6 Mar 1989||21 May 1991||St. Jude Medical, Inc.||Centrifugal blood pump and magnetic coupling|
|US5044882 *||12 Sep 1989||3 Sep 1991||Ube Industries, Ltd.||Precessional centrifugal pump|
|US5049134 *||8 May 1989||17 Sep 1991||The Cleveland Clinic Foundation||Sealless heart pump|
|US5055005 *||5 Oct 1990||8 Oct 1991||Kletschka Harold D||Fluid pump with levitated impeller|
|US5092879 *||5 Mar 1990||3 Mar 1992||Jarvik Robert K||Intraventricular artificial hearts and methods of their surgical implantation and use|
|US5112200 *||29 May 1990||12 May 1992||Nu-Tech Industries, Inc.||Hydrodynamically suspended rotor axial flow blood pump|
|US5145333 *||1 Mar 1990||8 Sep 1992||The Cleveland Clinic Foundation||Fluid motor driven blood pump|
|US5147186 *||4 Jan 1991||15 Sep 1992||Bio Medicus, Inc.||Blood pump drive system|
|US5205721 *||13 Feb 1991||27 Apr 1993||Nu-Tech Industries, Inc.||Split stator for motor/blood pump|
|US5211546 *||11 May 1992||18 May 1993||Nu-Tech Industries, Inc.||Axial flow blood pump with hydrodynamically suspended rotor|
|US5267940 *||6 May 1991||7 Dec 1993||The Administrators Of The Tulane Educational Fund||Cardiovascular flow enhancer and method of operation|
|US5324177 *||3 May 1991||28 Jun 1994||The Cleveland Clinic Foundation||Sealless rotodynamic pump with radially offset rotor|
|US5370509 *||8 Dec 1993||6 Dec 1994||The Cleveland Clinic Foundation||Sealless rotodynamic pump with fluid bearing|
|US5376114 *||5 Feb 1993||27 Dec 1994||Jarvik; Robert||Cannula pumps for temporary cardiac support and methods of their application and use|
|US5755784 *||4 Nov 1994||26 May 1998||Jarvik; Robert||Cannula pumps for temporary cardiac support and methods of their application and use|
|US5762599 *||2 May 1994||9 Jun 1998||Influence Medical Technologies, Ltd.||Magnetically-coupled implantable medical devices|
|US5776190 *||19 Oct 1994||7 Jul 1998||Jarvik; Robert||Cannula pumps for temporary cardiac support and methods of their application and use|
|US5851174 *||17 Sep 1996||22 Dec 1998||Robert Jarvik||Cardiac support device|
|US5888241 *||19 Nov 1997||30 Mar 1999||Jarvik; Robert||Cannula pumps for temporary cardiac support and methods of their application and use|
|US5965089 *||3 Oct 1997||12 Oct 1999||United States Surgical Corporation||Circulatory support system|
|US6123725 *||11 Jul 1997||26 Sep 2000||A-Med Systems, Inc.||Single port cardiac support apparatus|
|US6416215||14 Dec 1999||9 Jul 2002||University Of Kentucky Research Foundation||Pumping or mixing system using a levitating magnetic element|
|US6716189||8 Jun 1999||6 Apr 2004||United States Surgical Corporation||Circulatory support system|
|US6723039 *||27 Apr 2001||20 Apr 2004||The Foundry, Inc.||Methods, systems and devices relating to implantable fluid pumps|
|US6758593||28 Nov 2000||6 Jul 2004||Levtech, Inc.||Pumping or mixing system using a levitating magnetic element, related system components, and related methods|
|US6858001||25 Sep 2000||22 Feb 2005||A-Med Systems, Inc.||Single port cardiac support apparatus|
|US6899454 *||9 Jun 2004||31 May 2005||Levtech, Inc.||Set-up kit for a pumping or mixing system using a levitating magnetic element|
|US6976996||14 Oct 1997||20 Dec 2005||A-Med Systems, Inc.||Transport pump and organ stabilization apparatus including related methods|
|US7037253||8 Mar 2004||2 May 2006||The Foundry Inc.||Methods, systems and devices relating to implantable fluid pumps|
|US7182727||11 Feb 2005||27 Feb 2007||A—Med Systems Inc.||Single port cardiac support apparatus|
|US7264606||5 Apr 2004||4 Sep 2007||United States Surgical Corporation||Circulatory support system|
|US7467929||18 Feb 2002||23 Dec 2008||Berlin Heart Gmbh||Device for axially conveying fluids|
|US7691046||10 Jul 2006||6 Apr 2010||Pumpworks, Inc.||Nondestructive fluid transfer device|
|US7699586||3 Dec 2004||20 Apr 2010||Heartware, Inc.||Wide blade, axial flow pump|
|US7909790||17 Apr 2004||22 Mar 2011||Novashunt Ag||Implantable fluid management system for the removal of excess fluid|
|US7934909||31 Oct 2007||3 May 2011||Berlin Heart Gmbh||Device for axially conveying fluids|
|US7972122||29 Apr 2005||5 Jul 2011||Heartware, Inc.||Multiple rotor, wide blade, axial flow pump|
|US7976271||16 Jan 2007||12 Jul 2011||Heartware, Inc.||Stabilizing drive for contactless rotary blood pump impeller|
|US7997854||16 Jan 2007||16 Aug 2011||Heartware, Inc.||Shrouded thrust bearings|
|US8007254||2 Jun 2006||30 Aug 2011||Heartware, Inc.||Axial flow pump with multi-grooved rotor|
|US8118724||4 Dec 2007||21 Feb 2012||Thoratec Corporation||Rotary blood pump|
|US8246530||5 Apr 2010||21 Aug 2012||Sullivan Paul J||Nondestructive fluid transfer device|
|US8353686||13 Oct 2009||15 Jan 2013||Thoratec Corporation||Rotor stability of a rotary pump|
|US8394048||15 Jan 2008||12 Mar 2013||Sequana Medical Ag||Vesicular shunt for the drainage of excess fluid|
|US8398577||31 Oct 2007||19 Mar 2013||Sequana Medical Ag||Implantable fluid management device for the removal of excess fluid|
|US8419609||5 Oct 2005||16 Apr 2013||Heartware Inc.||Impeller for a rotary ventricular assist device|
|US8512013 *||16 Jan 2007||20 Aug 2013||Heartware, Inc.||Hydrodynamic thrust bearings for rotary blood pumps|
|US8517973||16 Feb 2011||27 Aug 2013||Sequana Medical Ag||Implantable fluid management system for the removal of excess fluid|
|US8540477||4 Aug 2011||24 Sep 2013||Heartware, Inc.||Rotary pump with thrust bearings|
|US8668473||17 Aug 2011||11 Mar 2014||Heartware, Inc.||Axial flow pump with multi-grooved rotor|
|US8672611||12 Jul 2011||18 Mar 2014||Heartware, Inc.||Stabilizing drive for contactless rotary blood pump impeller|
|US8679171||1 Mar 2004||25 Mar 2014||The Foundry, Llc||Devices and methods for treatment of abdominal aortic aneurysm|
|US8684902||4 Dec 2007||1 Apr 2014||Thoratec Corporation||Rotary blood pump|
|US8771221||7 Mar 2013||8 Jul 2014||Sequana Medical Ag||Implantable fluid management device for the removal of excess fluid|
|US8790236||2 Jun 2006||29 Jul 2014||Heartware, Inc.||Axial flow-pump with multi-grooved rotor|
|US8852072||6 Feb 2009||7 Oct 2014||Heartware, Inc.||Ventricular assist device for intraventricular placement|
|US8882699||22 Aug 2013||11 Nov 2014||Sequana Medical Ag||Implantable fluid management system for the removal of excess fluid|
|US8932006||23 Sep 2013||13 Jan 2015||Heartware, Inc.||Rotary pump with thrust bearings|
|US9050405||26 Feb 2014||9 Jun 2015||Heartware, Inc.||Stabilizing drive for contactless rotary blood pump impeller|
|US9091271||18 Aug 2011||28 Jul 2015||Thoratec Corporation||Implantable blood pump|
|US20040115038 *||18 Feb 2002||17 Jun 2004||Peter Nuesser||Device for axially conveying fluids|
|US20040171904 *||8 Mar 2004||2 Sep 2004||The Foundry, Inc.||Methods, systems and devices relating to implantable fluid pumps|
|US20040191116 *||5 Apr 2004||30 Sep 2004||Robert Jarvik||Circulatory support system|
|US20040193245 *||1 Mar 2004||30 Sep 2004||The Foundry, Inc.||Devices and methods for treatment of abdominal aortic aneurysm|
|US20050096582 *||17 Apr 2004||5 May 2005||Burnett Daniel R.||Implantable fluid management system for the removal of excess fluid|
|US20140322022 *||17 Sep 2012||30 Oct 2014||Heartware, Inc.||Platinum-cobalt-boron blood pump element|
|WO1990015640A1 *||18 Jun 1990||27 Dec 1990||Univ Minnesota||Cardiac assist pump|
|WO1994009274A1 *||19 Oct 1992||28 Apr 1994||Cleveland Clinic Foundation||Sealless rotodynamic pump|
|WO2007040663A1 *||2 Jun 2006||12 Apr 2007||Heartware Inc||Axial flow pump with multi-grooved rotor|
|U.S. Classification||623/3.13, 417/420, 415/204, 416/3, 415/206, 415/10, 417/423.1, 415/217.1, 128/899, 415/218.1|
|International Classification||F04D13/02, A61M1/10|
|Cooperative Classification||A61M2001/1036, F04D13/024, A61M2001/1005, A61M1/101|
|European Classification||F04D13/02B3, A61M1/10C|