It would help to have more information. In a photo, it could just be a some sort of lighting effect, of course. I'm not up on Kirlian photography, though I know that some people have found ways to photograph a person's aura. My recollection is that that process shows colors in the aura which can then be interpreted by those with some expertise in these things. My own high sense perception is not particularly visual. It's more kinesthetic and conceptual.
What I do know is that we are profoundly affected by the thoughts that hang around us in our energy field. These can be conscious or unconscious and they don't necessarily even belong to us. The thoughts, beliefs and ideas of people around us can affect us, even if we are not aware of them. I don't have any idea what an orb might be, but if an intuitive placed a hand in the field in that location, they are likely to get some imagery that could provide a clue. If several people tuned in to the same location, they could compare their readings. It's always interesting when people come up with similar imagery. But it may also be valuable to consider diverse interpretations which may all contain some validity.
Most importantly, if the person with the heart orb is open to it, she might want to simply place a hand on her own heart and ask inside what is going on. Then, if she allows herself to feel her own feelings, she may be able to move to a new level with this awareness. If there is negative emotions, pain or trauma, some kind of energy clearing would be appropriate. A simple way to do that is to keep one hand on the heart and place the other over the forehead. Take some deep slow breaths and focus on the feelings, thought and imagery while balancing the energy between these two places.

it could be an attachment.

maybe something to be investigated?

thanks