Your question requires much informtion and to provide the information that will help is provided by the following link:
http://www.mayoclinic.com/health/coronary-artery-disease/DS00064/DSECTION=risk-factors
If you have any followup questions or comments you are welcome to respond. Thanks for sharing, take care,
Ken
The first step is to break the link of any bad lifestyle traits which may exist between your Mother and other relatives. Such as not smoking, not eating healthy foods, not exercising, leading a stressful life and not keeping blood pressure within normal limits. This would be a very good start.