My Father Undergo Angioplasty Nearly 9 Years Ago....3 Stents Are

My father undergo angioplasty nearly 9 years ago....3 stents are placed and two of them were placed adjacent to each other and in a very short period these two stents collapsed and block the veins completely. But at that time fortis doctors said that there is no need to do anything as natural bypass are there which are maintaining the blood flow and he can easily survive on medicine but now again myfather is having problem of high BP and doctors say that they will try to open the blocked stents by placing another stent...and i am very confused what should i do in this condition?????