Can heart disease be heriditary?

Hi there. I have a question. My mom has heart disease. She's 65. About 4 years ago she had 4 stints put in her heart because she had blockages in three arteries. Sometimes she gets short of breath, especially if she goes to a higher altitude. Lately she's been having some chest pains, pressure and told me that a couple of days ago she had to take 2 nitro-glycerin tablets to make it go away. She said if you have to take 3 then you're supposed to call 911 and go to the hospital. They checked her heart last month and didn't see anything with the normal tests. They wanted to do an angiogram but said it would have to wait until her kidneys were doing better because I guess the test is hard on the kidneys.
I'm just worried about her, I guess. To me, she's still pretty young.
Also, my half-brother had a heart attack about 6 years ago at the age of 42. He was smoking a lot, though and under a lot of stress. My mom is not a smoker.
I'm wondering if I need to be concerned that I could get heart disease? Could this be heriditary? I did get my heart checked out last year because I was having heart palpitations. I was under a lot of stress then, too. They said I was having PVC's and PAC's but that a lot of people have that and it looked like everything else was ok.
I'm not a smoker either. I'm just wondering if heart disease could be passed down and if I need to worry. My grandmother also had heart disease but not until she was in her 70's and it was controlled pretty well. Also not a smoker.
I guess I'm just thinking about this more because I'm getting older. I'm 43. Is there anything I should watch for or anything I can do? Or is it just something I wait and see if I get it or not? If it's heriditary is there nothing much that can be done?
I guess I've just been thinking about all of this for awhile and wondering. Thank you.
April

[Momto3]

One of the risk factors to developing heart disease is heredity.  Unfortunately, we can't do anything about the bad genes.  But, there's lots we can do about the other risk factors.  Try to get exercise, eat well, no smoking, have your cholesterol and BP checked periodically.

Take care and try not to worry.  Just try to watch out for the controllable risk factors.  

[April2]

I do. I just worry that maybe I don't have the greatest genes, lol. I guess there's not a whole lot I can do about that.
Thanks for replying back to me.