Some LifeVest (the company that makes the device) will partially pay for it. Talk to your doctor about it. He or she may be able to get this for you at no or very little cost. You can also contact the company. Google LifeVest on the web.
I wore a Life Vest for three days last year and was charged $3,200.00. This was during Thanksgiving Holiday and no one at my insurance company could be reached. The insuranced company denied coverage, stating that it was "unnecessary". It took me eight months, but the insurance company FINALLY paid for it. The prescribing doctor needs to send a detailed letter to your insurance company, explaining the need for the vest and hopefully this will clear things up. I also worked with the "appeals department" at the Life Vest company. They were very helpful.