Pregnancy and health issues

Does anyone else have past heart conditions? I have been seeing a cardiologist since 2015 trying to figure out what is causing my symptoms and we have narrowed it down to what we think it is, but now since pregnancy my symptoms are getting much worse. I can not do anything without almost passing out, even laying in bed. My heart palpitations are out of control and the chest pains are unreal. I get out of breath just walking to the kitchen and back and I'm worried something is going to happen to the baby because of this. Any advice?