Thank you for posting your question here, I will try to answer it to the best of my ability.
There are only three major steps you can take-
1) lifestyle changes - talk to a dietitian and have him make out a diet for you, it will usually consist of increased fruit intake and reduced intake of fatty or high cholesterol
food. Exercise may also be added to your lifestyle.
2)Medication- usually the first drug given in these cases is Aspirin
, now you may think why aspirin - the reason is because it stops blood from clotting, so it reduces the chances of your coronary arteries getting blocked by a clot. Other medication is given to reduce cholesterol levels i.e statins, beta blockers to reduce contractility of the heart and calcium channel blockers.
3)Minor surgeries - for example a bypass, a graft