What Does Having A Predominant Left Ventricle In Fetus Mean?

Hi. I am 30 weeks, 4 days pregnant with my first child. A little girl we are naming Reese. I had an ultrasound done last Tuesday, and followed up on Friday. The doctor told me that the sonographer found a predominant left ventricle. She then said its not larger or protruding, it is only assymetrical, so she is referring us to a specialist. That appointment is not until November 3rd. She said everything was probably fine and not to worry. But naturally. as a first time mother and a pediatric occuoational therapist by trade, I am worried.