Dynamic pumping performance of the Hemopump--a small intraventricular blood pump.

We studied the pumping characteristics of the Hemopump, a commercially available miniature intraventricular blood pump for temporary support of failing hearts. The Hemopump is an axial flow pump of which the characteristics can be described by turbomachine theory. Experiments with water and a mock circulation verified that the pumping characteristics of the Hemopump in terms of both pressure head and flow as a function of rotational speed, very well can be described by a first order differential equation. The influence of blood with its non-Newtonian character is being investigated.