You have something I have although I only have it about 1/10 the normal limit. You have about twice as much but I've seen it worse than that. The doctors as they have to give everything a name call it Gilbert's syndrome they don't know of any treatment. It is usually genetic but sometimes not. It is caused by excess billirubin (bile) not being extreted through the bile ducts but rather getting backed up in the liver and being excreted into the blood. (Look in the mirror are you yellow in the eyes or skin?) I'm told you can help it a few ways. Flushing will help supposely, taking liver cleansing herbs in addition will help. Also in addition some think that the cause maybe a narrowing of the bile ducts so magnesium supplemenation can help with that greatly. I've heard that milk thistle is very good for cleansing the liver. They say Gilberts Syndrome its not dangerous to have in fact it may help your heart, but I would say its better to get it under control as it maybe a sign your liver is congested.
My plans myself are to do a liver flush, liver cleansing herbs and keep supplementing with the magnesium thats in my mineral/calcium formula.