I am one of the few here who has known about mine for over a year, has not had symptoms but I have also decided not to treat it for the time being, I did have a bleed, however my bleed was from an aneurysm that the doctors were able to isolate and obliterate. Because my doctor was able to determine that this was the aneurysm that bled and not my AVM the AVM is still considered to be enraptured. Before my bleed I had no symptoms and even after having surgery for my aneurysm i have no symptoms that I am aware of.
As for why i decided not to treat is a person decision. For one thing i already went through brain surgery last year for my aneurysm (technically two brain surgeries, one to place a ventriculostomy in my brain to drain Cerebral spinal fluid and another do treat the aneurysm). WHile both surgeries were minimally invasive, it is brain surgery and the less brain surgery i have to have the better. I have a lot of life goals that I want to accomplish and with a lot of them I need to use my brain :p.
I have spoken about it at length with my doctor and mine is considered to be a grade 3/4, approx. 3cm in diameter, meaning that it is operable however my doctor also can't tell me what any deficits i may have after surgery due to the placement of my AVM. It is in my right parietal lobe but also boarders on the occipital lobe. Because removal of the AVM can cause issues to the surrounding brain tissue there is a chance i may have major issues afterwards with spacial relations, or motor issues with the left side of my body. I was given the option of having GK, but that would have a 75% chance of obliteration with a 5-10% chance of deficit. I have met quite a few people who have had gamma knife and a large majority of them have had issues with cerebral edema and tissue necrosis which is also something i want to avoid. The neurosurgeons I have talked to all agreed with me that proceeding for the time being with no treatment is probably the best option since they can't guarantee that i will come out unscathed and without major deficit that could affect my every day life and my ability to live it the way i want to.
I haven't stopped living my life after the diagnosis though. Since last year I moved to Alaska, did a 20 mile bike ride and climbed a 3500 foot mountain. I just watch my blood pressure to make sure that it is stable and if things start to feel difficult I slow down a little bit.
There is always the risk of a bleed...in my case I was told a 1% chance per year.But I also know that there are many new technologies coming out that could help the way we treat AVMs and am kind of holding out for some additional research that may lead to less invasive AVM treatments as well. They may not be doing a ton of research on AVMs specifically but we have to remember that gamma knife is primarily used and was researched for use a treatment for brain cancer. I used to travel a lot for work and I always carried my MRI and CT films with me, plus I would get the name of the nearest neurosurgeon that specializes in neurovascular surgery. I also have a medical alert bracelet that I wear as well as a wallet card that describes my issue along with mention of a history of hydrocephalus. Even here in Alaska I have a doctor that mine recommended and knows personally who can treat me in the event of an emergency. :)
I hope my experience has helped you somewhat. I am a little unique in my decision and I don't know if my decision will stand forever depending on technology and other medical advances we may experience.
I wish you so much luck and happiness and please let us know what you decide to do!