Thanks for the query.
certain physiological changes occur in the circulatory system like:
means increased heart rate
, missed beats, palpitations etc.
Decrease in blood pressure due to decreased vascular resistance.
Due to increased blood volume during pregnancy some amount of mitral regurgitation
can be seen.
So as these are normal findings and your as your ECG and ECHO are normal no need to bother.
Regular followups are enough.