My father had a health check up and the TMT test came out positive. The doctor has advised to go for angiogram. Are we going in the right direction? And can the angiogram turn out to be no blockages found? Are there any risks involved in angiogram ?

Yes, you're on the right track. A positive TMT (Treadmill Test) suggests that there may be reduced blood flow to the heart, and an angiogram is a standard follow-up to check for any blockages. It is possible that an angiogram might show no significant blockages; sometimes TMT results are positive due to other factors. Angiograms are generally safe, but they do carry minimal risks, such as bleeding, infection, or, rarely, an allergic reaction to the dye used.