* Medtronic Inc., the world's biggest pacemaker company, agreed to buy Xomed Surgical Products Inc. the leading maker of devices for ear, nose and throat surgery, for about $800 million in stock. Medtronic is offering 0.8 of a share, or about $60, for each share of Xomed. The acquisition, Medtronic's third-largest purchase this year, adds Xomed's drills, catheters and monitors to a product line that includes heart, spine and nervous-system devices. Medtronic, based in Minneapolis, has expanded its focus beyond cardiac products by buying companies such as spinal-device maker Sofamor Danek Group. Shares of Jacksonville, Fla.-based Xomed surged $6.38 to close at $57.63 on Nasdaq. Medtronic shares fell $2.13 to close at $74.56 on the NYSE.