A mechanical circulatory support device is provided that includes a housing containing separate first and second pumps, each pump having an inlet, an outlet, and an impeller. The device also includes an actuation mechanism within the housing and is movable from a first position to a second position to divert blood flow within the housing to one of the pumps or to bypass blood flow relative to one of the pumps within the housing. In the first position, the actuation mechanism directs blood flow exiting the first pump into a bypass passage so that blood flow bypasses the second pump, and in the second position, the actuation mechanism directs blood flow exiting the first pump into the inlet of the second pump. The first pump is an axial flow pump and the second pump is a centrifugal pump, and the actuation mechanism includes flexible hosing.

A mechanical circulatory support device is provided that includes a housing containing separate first and second pumps, each pump having an inlet, an outlet, and an impeller. The device also includes an actuation mechanism within the housing and is movable from a first position to a second position to divert blood flow within the housing to one of the pumps or to bypass blood flow relative to one of the pumps within the housing. In the first position, the actuation mechanism directs blood flow exiting the first pump into a bypass passage so that blood flow bypasses the second pump, and in the second position, the actuation mechanism directs blood flow exiting the first pump into the inlet of the second pump. The first pump is an axial flow pump and the second pump is a centrifugal pump, and the actuation mechanism includes flexible hosing.

A cooling system for a rotational medical device such as a blood pump comprising an electric motor, a rotational drive shaft and an impeller. The cooling system comprises at least one active fluid pump for moving fluid distally within an outer fluid flow channel to a point proximal of the drive shaft's connection with the impeller where the fluid is deflected and urged into a fluidly connected inner fluid flow channel. A portion of the fluid in the outer fluid flow channel is pumped toward the impeller and the remaining fluid flows proximally through the inner fluid flow channel and along the outer surface of the drive shaft, thereby removing frictional heat from the rotating drive shaft. Next, the fluid is urged to bathe the outer surface of the electric motor to remove heat from the motor. Finally, the heated fluid is removed from the system.

A cooling system for a rotational medical device such as a blood pump comprising an electric motor, a rotational drive shaft and an impeller. The cooling system comprises at least one active fluid pump for moving fluid distally within an outer fluid flow channel to a point proximal of the drive shaft's connection with the impeller where the fluid is deflected and urged into a fluidly connected inner fluid flow channel. A portion of the fluid in the outer fluid flow channel is pumped toward the impeller and the remaining fluid flows proximally through the inner fluid flow channel and along the outer surface of the drive shaft, thereby removing frictional heat from the rotating drive shaft. Next, the fluid is urged to bathe the outer surface of the electric motor to remove heat from the motor. Finally, the heated fluid is removed from the system.