It is reasonable to assume that the American Embassy in your country of residence will have access to any past visa applications or grants.
If you haven't done anything wrong in the past, then it doesn't matter.
I could see them asking you to confirm you had a visa in the past, and asking you what visits you did during that visa, just to make sure what they see on the system matches what you say. But there shouldn't be any repercussions if you're honest with them and have nothing to hide.
Do make sure you have everything they ask for. If they ask you why you didn't have all your information on the previous visa, you can honestly tell them that you tried to obtain it but couldn't.
Regards,
Vicky's Mom
