| abstract |
A blood circulation assistance device ( 1 ), for location around a blood conduit ( 20 ). The device comprises: an inflatable bladder ( 10 ) moveable between a contracted form and an expanded form, for compressing the blood conduit ( 20 ) to provide counterpulsation. Pump means ( 30 ) in fluid communication with the bladder ( 10 ) move the bladder ( 10 ) from the contracted form to the expanded form. The pump means ( 30 ) comprises a centrifugal impeller ( 62 ) rotatable about an axis ( 61 ) to effect pumping. The impeller ( 62 ) is moveable axially between first and second positions to effect a reversal of the direction of pumping. Control means ( 50 ), in communication with the pump means, is capable of monitoring the cardiac cycle of an individual and triggering the pump means ( 30 ) to move the bladder ( 10 ) to the expanded form at diastole. An outer cuff, surrounds at least a portion of the bladder ( 10 ), providing an outer limiting extent to the movement of the bladder ( 10 ). |