File:Piston blood pump enlarged surface area concept.png

Image showing how a piston/plunger-based (pulsatile) blood pump can have a very large surface area compared to continuous flow pumps. Note that this design is much different from the pump used in most pulsatile VAD's (the pump itself being much larger compared to the artificial blood vessel it is connected to compared to most pulsatile VAD's). The advantage of this type of piston pump is that its stroke speed (a.k.a. mean piston speed) can be quite slow, and so will not cause much erosion to the blood (compared to continuous flow pumps). This could in turn mean that blood clotting can be much less with these type of pumps.

Other differences to the pump design of most pulsatile VAD's is that

• it uses a simple solenoid coil rather than a electric motor.
• it has only 1 valve (shown in green)

The use of a solenoid coil should mean the whole is more durable/have longer service life. The solenoid can still provide the function of pushing the plunger forward/back, as the PCB connected to it should have the option of changing its polarity

Only 1 valve is used, since valves are generally a weak point

Note that the function of the piston could theoretically be taken over by a human muscle. Such a muscle could be grown in the lab and be completely biocompatible for the person it can be implanted to (so cause no rejection). The muscle could pump the blood in a much similar way as how a diaphragm pump operates. A human muscle would be much preferable over a eletric (piston pump) since it could last for as long as the person lives, and hence does not need replacement (or require the person to undergo further surgeries).