The Spindle Pump—A Nonpulsatile Blood Pump for Assisted Circulation

During the past few years the development of nonpulsatile blood pumps has been encouraged as an alternative to membrane pumps. Most of these pumps were planned for left ventricular or biventricular assistance and only some for cardiac replacement [1, 3, 6, 8, 10, 12–14]. While all were very durable and reliable, it quickly became apparent that they were plagued with various problems, such as traumatic hemolysis, thromboembolic complications, and sealing difficulties [1, 3, 7, 14]. Despite these problems several short-term clinical applications were risked [2, 9, 11, 15]. To deal with these limiting factors we chose the spindle pump concept, the essential aim being to achieve, by proper design, sufficient volume output at low rpm rates so as to minimize blood trauma [4, 5].