heart with arrow through it

Success on first try - but it was a total guess... :(

It looks like it should be difficult but i found it quite easy, as long as you start at the bottom of the heart (which is located on the bottom row 13th column) and know that the 7's are the sides of the heart it's rather easy :)

Easy. Thanks.

It's got a lot of ambiguity, but knowing what you're drawing makes it pretty easy to guess.