The catheterization is a very safe procedure with small risk of major complications. The typical results from this procedure fall into three general categories. Normal coronary arteries, mild disease which does not require any intervention or severe disease that may require further work. If further work is required depending on the degree of severity and your mom's comorbid conditions (Diabetes, heart failure) this can be fixed either by stents or by bypass surgery. The procedure is not painful, the patients are typically sedated and don;t feel much or remember much.
I saw your msg over on the other board. Left a note for you there. Give your mom a hug.