Suggest Complications With Atherosclerotic Disease

Hi, i'm Smitha. My father is 56 year old and he is suffering from Atherosclerotic disease in his left leg, near the limb (Which was diagnosed recently). His thumb finger of left leg is badly wounded. I'm afraid if this is some kind of serious disease. He is staying in Mysore, pls let us know to whom can we contact and let us know if it is a serious thing