Irvine-based Endologix has received Investigational Device Exemption conditional approval from the U.S. Food and Drug Administration to begin a clinical trial for a fully percutaneous approach to endovascular abdominal aortic aneurysm repair. The authorization allows the minimally invasive device maker to test the procedure using its IntuiTrak endovascular delivery system. AAA is a weakening of the walls of the aorta, which is the largest artery in the body.