question: Hi,  i am a 26 year old female para 3 and pregnant with number four. Since having my third i have had palpatations, and left chest/shoulder discomfort that comes on at random times, not worsened by exercise. I have had ambulatory monitoring (bp and trace) ecg (normal) and was diagnosed with sinus tachycardia, and a mild systolic mumur, but have cardiac issues in the family and am worried this discomfort may be related???