It is rare for arteries to get clogged again in a short time. It takes 4 to 5 years to clog up the arteries in a normal human being. But can happen. Do not worry
The doctor may prescribe
Topro type brood pressure medicine
Lasix as diuretics
Plavix
Aspirin daily
Statin drug like ZOCOR
Follow the medication routine. He will be fine. One concern, if he did not have diabetes before and suddenly finds himself to have one, here is the possibility.
The operation is a major trauma and he could develop Type 2 diabetes (it happens to pregnant women sometimes). Then they will give him insulin to take. The catch is, when he is on statin drugs it messes up the insulin regulation which means he may remain on insulin.
It happens to some people, your dad could be lucky not to have it.
If he is on Lasix, it depletes Potassium from the body and hence he may lose balance. So make sure to take K-DUR, the Potassium pill - that is a must. Otherwise, he may one day taking a shower and fall and hit his head and end up in hospital again with subdural and epidural hematoma.
Taking those precautions will greatly enhance everything.
Oh! Statin drugs also deplete CoQ10 - so take them regularly.
Good Luck