The invention relates to an intercardiac pump device comprising a pump (11) whose distal end (13) is connected to a cannula (15) which is provided with a suction head (16) for sucking blood. Said strainer is provided with a non-sucking extension (20) for stabilizing the position of said pump device in the heart and mechanically prolonging the cannula (15) without deteriorating hydraulic conditions. Said extension is also used in the form of a spacer in order to avoid that the suction head (16) adheres to a cardiac wall.