The IABP's monitor became "white" and IABP therapy completely stopped while on a CICU patient around 20.00. The on-call perfusionist was called in. By the time the perfusionist arrived the IABP re-established its full functionality. All power cables and connections were found intact by both the CICU nurses and the on-call perfusionist. The perfusionist swapped the faulty IABP with another cardiosave and the device was placed out of service for investigations.