Paxil and coumadin

My husband is on Paxil cr. Has been for about 8 years. (Was on Paxil and then Paxil cr. He has a plasic heart valve. He had surgery in 1988 first and then in 1996 he had an angorizim (spell?) by it. He has always been hyper and anxious, but this scared him so much. He is on coumadin, metoprolol, digoxin, and colestoral medications. He also started having siezures. He has been on dilantin for about 5 years and still had siezures. The siezures can be from just dizzy, vomiting, to a full grand mal siezure. No one can find out why...Recently he had been put on lamictal, by his nurologist. He has been very anxious, and just angry at the world and depressed. He argues over everything. Could it be that he has been on paxil for a long time and it isn't working anymore or could the lamictal cause this? He deffinelty needs help and I don't know where to turn. He also has had irregular heart beats. went to cardiologists but they say it is electrical, not circulatory and not dangerous. I took him to emergency the other night and they said the same. He is misorable. do you have any advise????