wow was it the stess /nucler test that said it was negative?
When and how did you find out that your circumflex artery was 60 to 70 percent blocked? If it is 70% blocked, are you taking a blood thinner or aspirin for it? If the artery is 70% blocked, I would imagine that the artery is spasming especially during a workout causing the pain. You should let your doctor know your symptoms.