Abstract Background Transthyretin amyloidosis (ATTR amyloidosis) is a rare. life-threatening disease caused by the accumulation of variant or wild-type (ATTRwt amyloidosis) transthyretin amyloid fibrils in the heart. peripheral nerves. and other tissues and organs. https://www.roneverhart.com/Hohner-C-7-NS-Harmonica-Carrying-Case-p36684/