For anyone who is 40 or older and overweight - take it from me, if you can avoid cardiac artery disease you should do so. For most people heart disease is entirely avoidable - though there's certainly a genetic element to it if my family is anything to go by.
Sorry to hear about your health issues LJ. Are you in the angiogram lottery? With luck you get stents. If not you get bypass surgery. In my case so far it's always been stents. Either way we're a hell of a lot more fortunate than our parents and grandparents.
Whatever the outcome, lose weight and start exercising 30 minutes a day or more. I switched to an almost completely vegetarian and largely fat and sugar free diet and lost 5 stone in 6 months (another tip - don't lose weight too fast or you can develop fatty liver disease and gall stones as I did). If there's a cardiac rehab program - join up. If not, then try and get into group training at a gym, or if you can afford it a personal trainer. Monitored exercise is a great way to build confidence. And if (or when) when the next heart attack comes you'll have "collateral" arteries and the heart attack won't be as bad, or if you're lucky maybe you'll even avoid the worst.