If in three arteries there is 40-50% blockage as per ct scan so is there anything which is to be worried or it is curable by medicines?

Depends on symptoms: Given ur age, any degree of narrowing is abnormal. But the real question is whether or not u r having symptoms because of the blockages. If u do develop symptoms... like chest pain, problems with exercise, EKG abnormalities, fluttering... then 1 or all 3 of these blockages need to be addressed. U could choose to get another opinion. Cardiac catheterization is the gold standard test. TTYD about it.

Depends: You should see a cardiologist who can evaluate the type of blockage and the extent. The cardiologist will then assign appropriate medicine or treatment if needed.