hi, thought I'd let you all know my recent experience. Had a numb tingly feeling in my left thumb then couple hrs later it had turned dark purple. GP sent me to A&E resulting in a,6 day stay in hospital, after CT scan, dollar scan on arm & echocardiogram it was determined I had a blood clot in my lower arm caused by my AF , even though had been taking Pradaxa at max dose for 4yrs! Have had pain in shoulder & upper arm for weeks beforehand thought was just strain etc but apparently its first sign of clot moving. Am.now on warfarin and arm still very painful, have had 1 more scary episode of thumb changing colour but after another hospital visit informed could happen every so often and only to worry go Dr if it spreads further. Its very rare it happens but please be aware if you get unexplained pain in shoulder.