Abstract: A method of estimating the blood flow rate of a heart ventricle assist device which is positioned externally of, or implanted in, a patient. The assist device comprises a blood pump having a rapidly rotating, electrically powered impeller, and comprises briefly interrupting power to the impeller to cause its rotation to slow. From this, blood viscosity can be estimated, which viscosity is used to obtain real time, estimated blood flow rates and pressure heads. Apparatus for accomplishing this is disclosed.

Abstract: A ventricular assist device includes a pump such as an axial flow pump, an outflow cannula connected to the outlet of the pump, and an anchor element. The anchor element is physically connected to the pump, as by an elongate element. The pump is implanted within the left ventricle with the outflow cannula projecting through the aortic valve but desirably terminating short of the aortic arch. The anchor element is fixed to the wall of the heart near the apex of the heart so that the anchor element holds the pump and outflow cannula in position.

Abstract: A method of estimating the blood flow rate of a heart ventricle assist device which is positioned externally of, or implanted in, a patient. The assist device comprises a blood pump having a rapidly rotating, electrically powered impeller, and comprises briefly interrupting power to the impeller to cause its rotation to slow. From this, blood viscosity can be estimated, which viscosity is used to obtain real time, estimated blood flow rates and pressure heads. Apparatus for accomplishing this is disclosed.

Abstract: An extracorporeal blood processing method using a blood circuit comprising a pair of blood passages attached to opposite flow ends of a blood treatment device and said blood circuit is mounted on a blood pump console, the method includes: withdrawing blood from a vascular system of a human patient and drawing the blood into the blood circuit; pumping the withdrawn blood through one of the pair of blood passages using a first blood pump of the console and into the blood treatment device; pumping the treated blood from the treatment device through the other of the pair of blood passages using a second blood pump of the console; infusing the treated blood from the other blood passage and into the vascular system of the patient, and periodically reversing a flow direction of blood through the pair of blood passages and blood treatment device.

Abstract: A demand responsive physiological control system for use with a rotary blood pump; said system including a pump controller which is capable of controlling pump speed of said pump; said system further including a physiological controller, and wherein said physiological controller is adapted to analyse input data relating to physiological condition of a user of said pump; and wherein said physiological controller determines appropriate pumping speed and sends a speed control signal to said pump controller to adjust pump speed; said system further including a physiological state detector which provides said input data indicative of at least one physiological state of said user, in use, to said physiological controller.

Abstract: A minimal intrusive cardiac support apparatus is disclosed which requires only one incision into a main blood vessel or heart chamber. The apparatus includes a pair of generally coaxial and slideably arranged cannulae (one inner and one outer) communicatively coupled to a blood pump for providing right-heart and/or left-heart cardiac support during cardiac surgery. Optional balloons may be mounted on the outside of the inner and outer conduits which can be selectively inflated to seal off the sides surrounding vessel or to deliver cooling fluid or medication to the surrounding tissue. Using the apparatus, a method of pumping blood through the body is also disclosed.

Abstract: An electrohydraulic energy converter useful in a circulatory assist device includes a housing defining a hydraulic fluid flow path and having first and second open ends. A left diaphragm is disposed on and seals the first open end of the housing, and a right diaphragm is disposed on and seals the second open end of the housing. A reversible axial flow pump is disposed within the housing for reversibly pumping hydraulic fluid along the hydraulic fluid flow path. In another embodiment, a blood pump is provided for alternately driving left and right systole in a circulatory assist device. The blood pump includes an energy converter having left and right blood pumping elements disposed on and sealing the two open ends of the housing. In a further embodiment, the axial flow pump includes a stator, a rotor rotatably connected to the stator, several impeller blades disposed around and extending radially outward from the rotor, and a motor for imparting mechanical movement on the rotor.