Design of an electromechanical pump system for training in beating heart cardiac surgery

Heart surgeons and trainees benefit greatly from continuous practice of bypass surgery and other cardiac operations. This is true of beating heart surgery where, unlike traditional methods, the heart is not arrested during the operation. At the Dept. of Surgery, University Hospital of the West Indies (UHWI) a system has been devised to simulate a beating human heart using intra-ventricular balloons, which are inserted inside a preserved in vitro porcine heart and made to pulsate using a pneumatic pump. The work is currently being developed in collaboration with the School of Engineering at the University of Technology, Jamaica (UTech) and the Dept. of Mathematics & Computer Science at the University of the West Indies (UWI), with the aim of producing a computer controlled device capable of simulating the range of intra-operative cardiac behaviours typically found in heart surgery. An electromechanical pumping system is described, based on a computer controllable linear actuator. A comparison of associated pulsatile pump choices is presented along with results of the design of a prototype diaphragm pump, which was tested with the porcine heart, demonstrating normal and abnormal beating, and ventricular fibrillation. A software architecture is also presented, showing how the heart may be controlled in a variety of beating modes over the course of a surgical training session.