A system comprising an associative memory, an input module, a query module, and a display module. An example method includes measuring a voltage waveform. The central lumen is provided with a valve means that is operable by the guide wire and when moved into a closed position by withdrawal of the guide wire, functions to prevent the flow of loose debris toward the proximal end of the catheter. The curvature of the nitinol wire is induced by extending or retracting the wire from the proximal end of the flexible distal portion while the distal end of the guide wire remains affixed to the distal end of the probe. The non-volatile memory stores values used by the engine controller to control operations of the printing engine.