Hi. Treatment for coronary artery disease usually involves lifestyle changes and, if necessary, drugs and certain medical procedures. Your father is having one complete block, which i think angioplasty is necessary. But trust your treating doctor, because he has seen your father and assessed his health status overall and felt that oral medications can manage his condition. His blood sugar is with in normal range. Cholesterol lowering drugs are available and it is usually prescribed for your father. By decreasing the amount of cholesterol in the blood, especially low-density lipoprotein (LDL, or the bad ) cholesterol, these drugs decrease the primary material that deposits on the coronary arteries. Boosting your high-density lipoprotein (HDL, or the good ) cholesterol may help, too. Your doctor can choose from a range of medications, including statins, niacin, fibrates and bile acid sequestrants. These drugs definitely will prevent fresh deposits of cholesterol and your father will benefit from this. Apart from this tell your father to quit smoking (if smoker), eat healthy foods (less fat), exercise regularly, loose excess weight and reduce stress if any. And also remember to monitor his blood sugar regularly. I Wish your father a good health