ROCHESTER, Minn. — The National Heart, Lung and Blood Institute has awarded Mayo Clinic an $11 million, five-year grant for research designed to find new and improved ways to diagnose and treat kidney disease caused by atherosclerosis, the clogging, narrowing and hardening of arteries, specifically, one or both renal arteries. This is a condition that affects nearly 7 percent of people 65 years old and older.