High reliability cardiac assist system

A high reliability cardiac assist system comprising:

• a. an electrically powered blood pump;
• b. dual electronics and battery systems capable of powering and controlling said blood pump, and being adapted to be implanted within a patient;
• c. dual transcutaneous energy transmission systems, each having a set of coils comprised of an external transmitter coil and a receiver coil adapted to be implanted within a patient, each set capable of providing power to either of said dual implanted electronic and battery system such that one of said external transmitter coils can be removed without discontinuing power transmission by the other;
• and
• d. an external battery system, capable of providing power to said implanted electronics and battery systems via either or both of said transcutaneous power transmission systems.

A high reliability hydrodynamic blood pump cardiac support system utilizing residual function of the natural heart as an emergency backup comprising;

• a. a hydrodynamic blood pump including inflow and outflow conduit means for connection between the left ventricle and aorta or between the right ventricle and pulmonary artery;
• b. a valve in said outflow conduit means preventing back-flow into the ventricle in the event said pump stops;
• and
• c. pump control system means adapted to vary the pump flow so as to cause said valve to close and open periodically at a frequency sufficient to prevent thrombosis due to stagnation of blood around the valve.

An electrically powered blood pump, comprising;

• a. Electric motor means including stationary windings and permanent magnet rotor means;
• b. Two bearings supporting both ends of said rotor means to permit rotation of said rotor means around a rotational axis thereof, one of said bearings located on the inflow side of said rotor means and the other of said bearings located on the outflow side of said rotor means, each said bearing adapted to be immersed in blood;
• c. A generally tubular conduit extending through said motor windings and defining an annular blood channel between said motor windings and said permanent magnet rotor means;
• d. hydrodynamic pump impeller means mounted upon said rotor means within said tubular conduit;
• e. An elongated, generally conical tapered hub of said rotor means maintained within said conduit and extending from the vicinity of said impeller means to said bearing on the outflow side of said rotor means, said tapered hub having an outer surface defining an angle of taper less than or about equal to 10 degrees relative to the rotational axis;
• and
• f. Stationary outflow stator blade means affixed to the inside of said tubular conduit and extending inward therefrom, such that said stator blade means redirects the rotational component of the blood flow produced by said impeller means towards a generally axial direction before said flow passes across the other of said bearings on the outflow side of said rotor means.

An axial blood pump rotor and blade structure adapted to provide optimal washing of bearings which support said rotor, comprising;

• a. a housing having a generally tubular channel through which blood flows;
• b. an elongated rotor mounted for rotation within said housing and having an inflow end and an outflow end;
• c. first bearing support means upstream of said rotor, said first support means supporting inflow bearing means;
• d. at least one pump impeller blade mounted upon said rotor and defining an inflow side and an outflow side;
• e. said elongated rotor defining an elongated rotor hub disposed between said outflow side of said impeller and said outflow end of said rotor;
• f. second bearing support means downstream of said rotor, said second support means supporting outflow bearing means;
• g. at least one stationary outflow stator blade fixed to an inner wall of said housing through which the blood is pumped and axially located between said impeller and said outflow bearing means, said outflow stator blade configured to redirect the rotational component of the fluid flow stream exiting the impeller to a generally axially direction before the flow stream crosses said outflow bearing means;
• and
• h. a pump flow channel within said housing comprised of the spaces between said housing, said rotor, said first and second beating support means and said inflow outflow bearings, configured such that, under the operating conditions of the pump, turbulence, flow separation, and flow stagnation sufficient to cause failure of the pump due to thrombus formation is prevented.

An apparatus for pumping blood, which comprises:

• a) a housing having an inflow opening and an outflow opening, and defining a blood path for blood to flow from the inflow opening to the outflow opening;
• b) a rotating member disposed within the housing and mounted for rotational movement within the blood path, the rotating member including an impeller blade for imparting pump energy to blood through the blood path;
• c) a first bearing mounting the rotating member, the first bearing disposed adjacent the outflow opening;
• d) a second bearing mounting the rotating member, the second bearing disposed upstream of the first bearing;
• and
• e) an outflow stator blade disposed between the impeller blade of the rotating member and the first bearing.

An apparatus for pumping blood, which comprises:

• a) a housing having an inflow opening and an outflow opening, and defining a blood path for blood to flow from the inflow opening to the outflow opening;
• b) a rotating member disposed within the housing and mounted for rotational movement within the blood path, the rotating member including an impeller blade for imparting pump energy to blood through the blood path and having an outflow portion defining a generally streamlined tapered configuration;
• c) a first bearing mounting the rotating member, the first bearing disposed adjacent the outflow opening;
• and
• d) an outflow stator blade extending from the housing member and being configured and dimensioned to direct blood flowing through the blood path axially across the first bearing.

An apparatus for pumping blood, which comprises:

• a) a housing having an inflow opening and an outflow opening and defining a blood path for blood to flow from the inflow opening to the outflow opening;
• b) a rotating member mounted for rotational movement about a rotational axis within the blood path of the housing, the rotating member including an impeller blade for imparting pumping energy to blood passing through the blood path, the rotating member having an outflow portion defining a generally tapered configuration, the tapered configuration defining an angle of inclination with respect to the rotational axis less that than about 10.degree.;
• and
• c) a drive mechanism for imparting rotational movement to the rotating member.

An apparatus for pumping blood, which comprises:

• a) a housing having an inflow opening and an outflow opening and defining a blood path for blood to flow from the inflow opening to the outflow opening;
• b) a rotating member disposed within the blood path, the rotating member including an impeller blade for imparting pumping energy to blood flowing through the blood path, the rotating member supported by inflow and outflow support struts and mounted for rotational movement by a first bearing associated with the outflow support strut and a second bearing associated with the inflow support strut, the inflow support strut having an axial post extending generally axially therefrom supporting the second bearing such that the juncture of the second bearing and the rotating member is disposed along the blood path a sufficient distance beyond said inflow support strut to be away from any local area of flow stagnation downstream of the strut and thus to prevent the accumulation of thrombus at the juncture;
• and
• c) a drive mechanism for imparting rotational movement to the rotating member.

An apparatus for pumping blood, which comprises:

• a) a housing having an inflow opening and an outflow opening and defining a blood path for blood to flow from the inflow opening to the outflow opening;
• b) a rotating member disposed within the housing and mounted for rotational movement within the blood path by a station try inflow beating disposed adjacent the inflow opening and a stationary outflow bearing disposed adjacent the outflow opening, the inflow and outflow beatings each including an axial load bearing surface and tapered load bearing surfaces, the axial and tapered load bearing surfaces cooperating and mating with corresponding axial and tapered load bearing surfaces associated with the rotating member to thereby enhance thrust load bearing capacity thereof, the rotating member having an impeller blade to impart pump energy to blood along the blood path;
• and
• c) a drive mechanism for imparting rotational movement to the rotating member.

An apparatus for pumping blood, which comprises:

• an electric motor with a rotor;
• a blood pumping member actuated by the rotor;
• a first electronic and power system including a first set of motor armature coils and associated battery for powering the electric motor to rotate the rotor and actuate the blood pumping member;
• a second electronic and power system including a second set of motor armature coils and associated battery for powering the electric motor to rotate the rotor and actuate the blood pumping member;
• and
• the first electronic and power system operable simultaneously with the second electronic and power system, each of the first and second electronic and power systems capable of individually operating the electric motor to actuate the blood pumping member such that in the event of failure of either the first or second electronic and power systems, the electric motor and blood pumping member will continue to operate driven by the remaining electronic and power system.