If you have angina, and have not been offered one, or have refused one, then talk it over with your doctor. Many heart patients fear that they may have their next heart attack before they are called to hospital. Happily there is a lot they can do in the meantime to help their hearts heal themselves, so that they will be fitter when they reach the top of the waiting list. The first step is to avoid smoking at all costs, including other people's. So if you smoke, you must stop and never even think of lighting up again.
Tobacco hurts the heart in many ways.
It causes clotting in arteries, it narrows arteries further, it pushes deadly carbon monoxide into the red blood cells and the heart muscle cells, and it covers the lung surfaces with a thin film of tar, so making the intake of oxygen from the air difficult. Other benefits come from losing any excess weight. That means eating healthily, preferably small meals regularly and not a big main meal once a day. It also means exercising to your ability, without provoking chest pain. Your doctor will advise on what you can do, and what you shouldn't.