Quantitative evaluation for anastomotic technique of coronary artery bypass grafting by using in-vitro mock circulatory system

This study focuses on the development of self-training system for surgical operation and quantitative evaluation of the surgical skills. Our group has developed a self-training system for anastomotic technique in Coronary Artery Bypass Grafting (CABG) to contribute the education of cardiovascular surgery without a risk to patients. The self-training system consists of following portions, 1) "YOUCAN", coronary and graft vascular silicone model, 2) "BEAT", a device, simulating stabilized myocardial surface, and 3) Quantitative evaluation system based on in vitro mock circulatory system. The coronary and graft model has been anastomosed by expert and trainee cardiac surgeon. The anastomosed model was mounted onto test section of the in vitro mock circulatory system then identical waveforms of coronary artery was applied into the inlet of an anastomosis. The energy loss was quantified as a pressure difference between proximal and distal ends of anastomosis. The energy loss was obtained as 67.3±1.75mJ (trainee) and 41.3±3.08mJ (registered surgeon). It was founded that average energy loss by expert surgeon was lower by 38.6% than that by trainee surgeon. The major difference among the models of expert and trainee was the Effective Orifice Area (EOA) of the anastomosis. Through the experiment, EOA was confirmed by image analysis as 2.73 mm ² for an expert against 0.534 mm² for a trainee. In conclusion, it was suggested that the anastomotic skill among expert and trainee surgeons could be hydrodynamically differentiated by using in vitro mock circulatory system.