My father age 69yrs, had heart attack some 10 years back and then he got stent in center artery. Recently from angiograph, doctor found RCA is fully blocked, but blood is seen on either side of blockage. Left one has some 60%+ blockage. That center one with stent have some blockage little farther from stent position. So suggested Bypass. As such my father is doing fine, so he is not agreeing for By pass. He takes his medicine regularly. Now some one suggested Stress Thallium test. Will it serve any purpose, post angiograph done recently ? Any alternative. One of his doctor, suggested in that case, it may go for stent in RCA which shows full block. Any comment.