In blood perfusion during cardiac surgery or ventricular assistance, for treating cardiac insufficiency, use is currently made of a centrifugal pump that generates a linear flow in the circulatory system, counter to the pulsating flow generated by the heart. According to the invention, a pulsating linear flow is achieved for blood perfusion by providing, in the interior wall of the chamber or casing of the pump (3), an elastic lining (8) in the form of a bell-shaped membrane that inflates and deflates, producing variations in volume and changes in pressure that give rise to a pulsating effect in the flow at the outlet (6) from the pump (3). At the inlet (5) to the pump (3) there is a non-return valve formed by an annular thickening (11).
