Is Switching From Plavix To Coumadin Safe For Treatment Of Cardiomyopathy?

My husband has had 3 stents over the past few years. He has cardiomyopathy. He is currently taking Plavix and aspirin. His doctor thinks he wants to stop the Plavix and put him on Coumadin to reduce any risk of strokes even though my husband has never had a stroke. Your advice? Thanks.