Is Bypass Surgery A Possibility Based On Available Clinical Information?

I'm scheduled to have an angiogram next Monday. I am 33, male, never smoked, was a light drinker (1-2 a week) until recently and I do not drink any more. Diet could be better but cholesterol was 192 last time I had it checked. BP has always been low. Not overweight, no diabetes, Pretty active ( Golf, Gym, Softball) Family History of Heart Disease ( Father died at 44) . Was having lightheadedness and shortness of breath climbing stairs recently. Went to have a echo-cardiogram ( which was completely normal) and a stress test (which my BP dropped to 90/60 in the 6-9 minute mark. Doc put my on beat blocker and aspirin regimen. What are the chances of having 1.) A stent put in my artery and 2.) What are the chances of bypass surgery for a guy my age with the info I have provided to you. I am in a bit of denial with all of this because of my age and that I've taken pretty decent care of myself. I was always an active kid and it carried over to adult life. I'm more worried about Bypass surgery. How is it determined that I would need it looking at the test result? This is all to scary.