Week 20 health concerns?

New mama here! I went to the hospital the other day to find out the gender (I won’t know till the 9th at my gender reveal🥰) And I was wondering if there’s any other mamas out there that have been told their baby has a small bright mark on their heart. I’d greatly appreciate a second opinion, and if it goes away on its own. The doctor said it’s most likely calcium and nothing to worry about and that she’s never seen it correlate with Down syndrome but there a possibility and that another in depth ultrasound will need to be done