A blood pump (1) comprises a pump casing (2) having a blood flow inlet (21) and a blood flow outlet (22), and an impeller (3) arranged in said pump casing (2) so as to be rotatable about an axis of rotation, wherein the impeller (3) has blades (31) sized and shaped for conveying blood from the blood flow inlet (21) to the blood flow outlet (22). The blood pump (1) further comprises an outflow cannula (4) having an upstream end portion (41), a downstream end portion (43) and an intermediate portion (42) extending between the upstream end portion (41) and the downstream end portion (43). The upstream end portion (41) of the outflow cannula (4) is connected to the pump casing (2) such that blood is conveyed from the blood flow outlet (22) of the pump casing (2) into and through the intermediate portion (42) of the outflow cannula (4) towards the downstream end portion (43) of the outflow cannula (4), wherein the downstream end portion (43) has a blood flow outlet (44) through which blood can exit the outflow cannula (4). At least a portion of the intermediate portion (42) of the outflow cannula (4) has an outer diameter that is larger than an outer diameter of the pump casing (2).
