It's amazing how quickly nitroglycerin works actually. I have a few older relatives who basically don't go anywhere without it, for fear of having an attack.
Unfortunately that means I'll probably be at risk for angina as well if I'm not careful since heart disease is hereditary. I'm hoping if I keep up a good diet and exercise regime it won't affect me as much, or as soon, but unfortunately, there's no action you can take that will completely guard against heart disease.
At least I basically know what angina pain feels like and, who knows? By the time I develop it they may have some kind of foolproof cure for it.