I tell people to never assume that the doc read your medication list. Even if appears that it was being read, what if the phone rang or the nurse interrrupted just as the eye skimmed over the warfarin? There is no way than anyone can know everything or notice everything.
Aspirin works well on clots that form in arteries where the blood is flowing fast. Warfarin works better when the blood is sluggish. In the heart that is supposed to come as original equipment, the valves are not flat - they flap a little. Also the heart squeezes blood from around the edges. When you get a poor imitation of the ideal, the valve is like a door. It is flat (doesn't flap)and when it opens there is blood trapped behind the door. The valve sewn into place and the heart can't squeeze every last drop of blood out. So you need warfarin to keep that sluggish blood from clotting. Aspirin probably adds little benefit and little risk. Plavix is a more potent clot inhibitor but still like aspirin. Bonnie's neighbor might have come close to bleeding to death, but we have all heard that way too many times to take it at face value.
At the meeting I was at last week one of the speakers was a professor of obstetrics. He commented that most OBs estimate the blood loss from a c-section at 1,000 ml (about a quart) but that it is typically about 1,500 ml (a quart and a half) and that blood is only rarely given for an uncomplicated C-section. His point was that all the worry about stopping warfarin for teeth cleanings, colonoscopies etc is probably just myth since very few times will one of these procedures result in more blood loss than a C-section.
Leaving in the morning for a hot spring in the mountains where there is little, if any, cell phone or internet service so don't expect rapid answers.
