An extravascular pulsation blood pump possesses a bidirectionally acting pumping system (P, M) having a pump (P) which is connected via a first conduit (L1) to the left ventricle (LV) and via a second conduit (L2) to the aorta (AO). By means of a control means (St), the pump (P) is operated alternately in one and the other direction according to a given cardiac rhythm, so that alternately blood is sucked through the first conduit (L1) and simultaneously blood ejected through the second conduit (L2) to the same extent, on the one hand, and blood is sucked through the second conduit (L2) and simultaneously blood ejected through the first conduit (L1), on the other hand. The pulsation blood pump combines the functions and advantages of an extravascular copulsation pump with those of an extravascular counterpulsation blood pump.
