I handled a Heym and noticed it had a very pronounced palm swell. I am right handed. It was actually the first time I had handled a double Heym and it felt really nice - I think the swell seemed to help it point more positively. Traditionally, I don't know if the swell is for increased grip, recoil absorbtion or what but it did feel nice.
I do not know if Heym makes their doubles in right or left hand specifically. Worth looking into.