An intraventricular pump including a fixed housing with a top part forming a propulsion chamber propelling fluid towards the top end, and a bottom part forming a stator and connected to the top part, at least one side opening between the top part and the bottom part, and forming an inlet chamber for fluid entry from the outside towards the propulsion chamber, a motor unit formed by the stator in which first magnetic elements are arranged, a bell-shaped rotor including second magnetic elements for magnetic coupling with the stator first magnetic elements, the bell having at least one opening in its top part creating a reverse fluid flow from the inlet chamber to the base of the stator via a rotor-to-stator passage, a transmission shaft including at least one connecting arm holding the bell above the stator, the transmission shaft coinciding with the bell rotational axis being coaxial.