My husband is 54 ,February of this year he had a stent put in his right leg. Three months later (May) he had to have two more upper and lower area of the same stent. He was put on xrellato ,he does heart problems. Cabbage in February 2011, six stents January 2014. He is diabetic,high blood pressure,. Now is having pain and swelling in ankle. What may be causing this?