I had surgery May 2010 to replace my ascending aorta, aortic valve and aortic root with a St Jude grafted valve. My inr range has always been 2.5-3.5. My Coumadin clinic insists that I only be given 5mg warfarin. I’m supposed to split pills and then take different does on different days to get the weekly total to come out right. I test myself weekly with Coaguchek xs. My inr has been 3.4, 3.5, 3.5 and 3.6. I have been taking 7.5 mg/day. I want to change to 7mg/day. Coumadin clinic wants me to take 7.5 for 6 days/week and 5 on 1day. My cardiologist intervened several years ago and I got 1 mg pills. Now Coumadin clinic is refusing to give me anything but 5. I left a message for my cardiologist. Meanwhile I am really stressed. Does anyone else have this problem? Or even understand why? I get the feeling that the RN I have to deal with just wants to exert her control over me.