Being a pharmacist, I know there is at least one blood pressure medication that can be taken during pregnancy, it is called methyldopa. Seeing as I do not know anything at all about your disease history, drug history, allergy history or anything about you for that matter....I would ask your ob/gyn about his/her feelings on the use of methyldopa in pregnancy and you could then take that information to your cardiologist.
As far as cholesterol meds go, no there aren't any that I would think you could take. Metamucil (the fiber supplement) has been shown to decrease total cholesterol by up to 10%, so that could be something you could discuss with your cardiologist as well.
Again, I am not trying to assume I know anything about you...I'm just giving some general information that you can then take to your doctors.
Hope this info helps.
Leslie