High degree of realism in teaching percutaneous coronary interventions by combining a virtual reality trainer with a full scale patient simulator.

The virtual reality coronary angiography simulator "CATHI" (Catheter Instruction System, Mannheim, Germany) simulates coronary arteries with implemented vessel lesions in virtual patients. Like similar systems the software model runs on common PC systems, which are linked to the mechanical device for manual training. We combined the advantages of this skill trainer with the near to reality assembly of a cardiac catheterization laboratory (Cath-lab) by connecting it to a full scale simulator (HPS, METI, Sarasota, FL). We present two methods of synchronizing the heartbeat between both simulation devices. Method A-the hardware solution-uses the electrocardiogram-synchronization signal of the HPS as a pacemaker for CATHI's heartbeat. Method B, a more sophisticated software solution, uses a communication protocol between the HPS software and the CATHI system to realize bi-directional data exchange. In 14 identical courses we performed four different scenarios using the above described setup, all of which had to be undergone by the 143 participants (including nursing staff, experienced- and inexperienced cardiologists). The synchronization of the two systems contributed to a close to reality situation. Scenario control was accomplished via commercially available HPS-software. Tachycardic and bradycardic arrhythmias were predetermined by predefined scenarios of the HPS-software, the trainee's intervention resulting in realistic treatment outcomes. Using either method, the transmitted signals resulted in the same heartbeat in the CATHI-system, making the cardiologic interventions more difficult but more realistic.