Hi Pat. I am not a doctor. But I was just diagnosed with DVT, for the second time in two years. The doctors have no idea why I am getting this. I defy all the causes of getting this. I never had a heart attack, never had severe trauma to the leg, and, being a 44 year old male, I have never been pregnant, and I am very, very active. All my tests on my blood came back, both times, negative, I have nothing in my blood to cause this clotting. I too, right now, am on Coumadin. But, the first time I was on it, I didnt have to be on it for my entire life. Ask your doctors, or vascular surgeon, if they know what caused the DVT in the first place. If you husband is like me, nothing is found to cause it, he should be able to come off the Coumadin after about 6 months. Maybe, like they told me, it was a freak thing. But, 2 years later, mine did come back. It came back as a Superficial, and a DVT also. So now, that I have a history of it recurring, I may have to go this Cpumadin, for the rest of my life. Lots of luck to you and your husband.