The power analysis of study is based on non-inferiority hypothesis, i.e. to show that paclitaxel eluting stent is not inferior to bypass surgery in 24 month patency. With accepted marginal for equality 5%, assuming surgical group patency 75% and non-inferiority margin 10% and using 1:1 randomization the sample size for a power of 80% to detect non-inferiority of the test treatment is 590 (295/295).