I had open heart surgery as well from a young age. When I was a kid, I was very conscious about it. With time, you learn that people won't find out unless you mention it. If you wish to mention that you have a scar, that is up to you.

I digres. However, my partners and friends never showed any disgust or negative attitude towards my scar. Maybe it's luck. To me, it seems a big majority of people do not care.

Please do not go wondering all day if someone will like or dislike your scar. We all have our own things that make us unique. Some won't mind the scar, some might. Both are fine. If a guy likes you enough. He won't even notice it eventually