Abstract: Artificial heart type devices are made into practical heart assist devices by making the blood chambers of the device disposable or by adapting the blood chambers to accept disposable inserts. The inserts have extensions which protrude through the inlet and outlet ports of the chambers to connect to the blood system of a living body.

Abstract: A pump and valve system having particular use as an artifical heart for human or animal implantation has long-lasting wear characteristics by imparting a relatively slow start ramp to the drive voltage for the pump drive. The ramp reduces the shock to the valves and thus reduces wear. The relatively slow ramp-down of the drive voltage also reduces wear similarly.

Abstract: A mechanical heart for implantation into the human body is run at a higher frequency which is a harmonic multiple of a normal heart beat frequency, and the pump chamber volume is reduced, proportionately to the increased pumping frequency. The circuit for controlling the frequency includes a phase locked loop for implementing a predictive algorithm which adjusts the frequency dynamically based on heart muscle nerve ending signals to synchronize the circuit output to the biologically determined heart beat. The reduced displacement permits use of a smaller compliance chamber. A novel interconnection between the motor chambers of a plurality of such pumps eliminates the need for venting and compliance chambers in a totally implanted heart system.

Abstract: A pump adaptable for use as a human heart includes first and third pump chambers separated from an intermediate second chamber which may house a motor. The chambers are separated by diaphragms which may be alternately driven. A pump is achieved which needs no venting. Each of the first and third chambers can pump blood in operation and can be connected in series or separately to the ventricles of the heart.

Abstract: A pump has a housing that is divided into two chambers by an element that is driven in a push-pull manner so that the volumes of each of the two chambers are alternately enlarged and reduced. Both chambers are in the path of fluid through the pump.The chambers of a diaphragm pump in a preferred embodiment are defined by a piston with a hollow annular shape having a magnetic rod secured at its center. The piston travels along the axis of the rod to seat against the conforming surfaces of a hollow housing. The chambers are isolated by a flexible annular diaphragm secured to the piston and a center line of the housing. When adapted as an artificial heart, both chambers fill with blood, one being connected between veins and the lungs, the other being connected between the lungs and arteries.