William J. Schroeder now walks up to...

William J. Schroeder now walks up to two blocks a day through hospital corridors and has lost 17 pounds with diet and exercise, 45 days after receiving an artificial heart, a hospital spokesman said. Schroeder, 52, weighed more than 200 pounds at one point after the operation but now weighs 183. He remains in satisfactory condition at Humana Hospital Audubon, in Louisville, Ky., where he received a Jarvik-7 plastic and metal pump on Nov. 25 and suffered three minor strokes on Dec. 13.