Medical-device maker Guidant ( GDT) plans to expand its stent factories in Southern California, the company said Thursday. Two new buildings, adding 300,000 square feet to its current facilities, will house programs for Guidant's drug-coated, carotid artery and absorbable stents, as well as other endovascular businesses and new technologies. Guidant expects to break ground on the new facilities in the second quarter, and it anticipates completion of the project in late 2007. Earlier this year, Guidant agreed to be acquired by Boston Scientific ( BSX) after choosing it over another suitor, Johnson & Johnson ( JNJ). As part of the agreement, Guidant's endovascular business will be acquired by Abbott ( ABT). Guidant shares dipped 15 cents to $77.27. Abbott shares were 22 cents lower, at $45.03.