A simplified cardiopulmonary bypass technique for animal experiments on implantable ventricular assist devices.

We have developed and report on a simplified cardiopulmonary bypass technique for experiments on implantable ventricular assist devices in calves. We used an electromechanical implantable ventricular assist device with a double cylindrical cam in three calves. Cannulas for the ventricular assist system were designed to be inserted between the left atrium and the descending aorta. We used the outflow cannula of the ventricular assist device, anastomosed to the descending aorta, as a temporary arterial return route for the cardiopulmonary bypass. A cannula for venous drainage was iserted into the right ventricle through the pulmonary artery. There were no problems related to the procedure and the cardiopulmonary bypass was succesful. In conclusion, this simplified cardiopulmonary bypass technique without neck incision in calves, as used in developmental work involving implantable ventricular assist devices, can be reliably performed.