Heart assist device

Abstract

A ventricular assist device comprising a housing defining an interior space, at least two ports opening into said interior space, and at least one pump for pumping blood between the ports through said interior space, the ports and interior space providing a continuous blood flow path that is not interrupted by valves.

1 . A ventricular assist device comprising a housing defining an interior space, at least two ports opening into said interior space, and at least one pump for pumping blood between the ports through said interior space, the ports and interior space providing a continuous blood flow path that is not interrupted by valves. 
     
     
         2 . A device according to  claim 1 , wherein said housing defines a substantially cylindrical interior space. 
     
     
         3 . A device according to  claim 2  and comprising a pair of pumps for pumping blood between the ports through said interior space, each pump comprising a pusher plate disposed at an end surface of the interior space. 
     
     
         4 . A device according to  claim 3 , each pump comprising a driving device disposed between the pusher plate and an inner surface of the housing. 
     
     
         5 . A device according to  claim 4 , wherein the driving device comprises a linear oscillator actuator. 
     
     
         6 . A device according to  claim 3 , wherein the or each pusher plate comprises an electroactive polymer material. 
     
     
         7 . A device according to any one of  claims 3  to  6  and comprising a flexible diaphragm coupling the edge of the or each pusher plate to an interior of the housing. 
     
     
         8 . A device according to any one of  claims 2  to  7 , each said port comprises a curved tube that substantially retains its shape in situ, the direction of curvature of the ports being substantially opposite. 
     
     
         9 . A device according to  claim 8 , wherein said ports open into said interior space at substantially diametrically opposed locations. 
     
     
         10 . A device according to  claim 8  or  9 , wherein said ports open into said interior space at axially spaced locations. 
     
     
         11 . A device according to any one of  claims 8  to  10 , wherein said ports open into the interior space substantially tangentially to the inner surface of the housing defining the inner space. 
     
     
         12 . A device according to any one of the preceding claims and being configured to fit within the chest cavity of a patient, adjacent to the heart. 
     
     
         13 . A device according to  claim 12  and being configured to allow a first of said ports to be grafted to a posterolateral section of the ascending aorta and a second of the ports to be grafted to an auterolateral section of the ascending aorta or to the aortic arch. 
     
     
         14 . A ventricular assist system comprising:
 a device according to any one of the preceding claims;   a power supply coupled to the or each pump; and   a controller for synchronising the operation of the or each pump to the phases of the heart.   
     
     
         15 . A system according to  claim 14 , said controller causing the or each pump to counter-pulsate with respect to the left ventricle. 
     
     
         16 . A system according to  claim 15  and comprising a sensor for detecting an ECG signal of a patient, the sensor being coupled to said controller. 
     
     
         17 . A method of treating a human body and comprising implanting a ventricular assist device within the chest cavity of the body, attaching a first port of the device to a posterolateral section of the ascending aorta and attaching a second port to an auterolateral section of the ascending aorta or to the aortic arch, and operating the ventricular assist device to pump blood between said first and second ports. 
     
     
         18 . A method according to  claim 17  and comprising operating the ventricular assist device as a counter-pulsator, pumping blood between said ports during the ventricular diastole phase. 
     
     
         19 . A method according to  claim 18  and comprising operating the ventricular assist device to pump during certain diastole phases and to rest during intervening diastole phases. 
     
     
         20 . A method according to any one of  claims 17  to  19 , said ventricular assist device being a device according to  claim 1 . 
     
     
         21 . A device substantially as described herein with reference to  FIGS. 2 to 5  of the accompanying drawings. 
     
     
         22 . A method substantially as described herein with reference to  FIGS. 6 to 8  of the accompanying drawings.