the item information is sent to authorize.net using the Full Details cart calcualtion
in the cart object, go to the calculation tab.
by default the ful details caclulation is:
[Quantity] . ' ' . [Name] . ' (' . [ID] . ')'
this passes the quantity, Name and ID number.
you can edit that to include other columns, for example:
[Quantity] . ' ' . [Name] . ' ' . [PupTentName] . ' ' . [PupTentNumber] . ' (' . [ID] . ')'