Yes, a CT scan 64-slice angiogram is an alternative to the intervention of a cath angiogram. Because there has been too many unnecessary stent implants, there are quidelines for treatment of angina and suspected CAD.
If angina (chest pain) can be controlled with medication, then treat medically. If angina is not controlled, then stent occlusions greater than 70%. In the event there is an emergency with an occlusion then a by pass. A bypass may also be apropriate if the occlusion is located that makes a stent not possible or the lesion is too long tortuous,etc.
For more than 5 years I have a totally blocked LAD and a 72% blocked circumflex, medication controls angina and there has been no progression. You can google COURAGE study, and the statistics show there is no difference in life span or any other benefit with a stent or bypass over medications.