International circulation: As we know， you have done outstanding work on PCI in left main disease. Do you think stents can replace surgery in left main disease? Dr. Park: Yes， of course I think it can. However， currently we are in somewhat of a transient period. We have changed from 100% surgeries to now a mixture of approximately 50% of cases handled by PCI and the remaining by surgical intervention. Personally， I think we cannot replace PCI with surgery 100%. A very selected group of patients had isolated left main disease， isolated main with a single vessel disease， a SYNTAX score less than 33， stenotic lesion disease those kind of lesions. Those kinds of patient subsets should be treated with PCI.