A new device could greatly simplify the surgery required to deal with aneurysm, according to a research team at Stanford University. An aneurysm -- a ballooning of a weakened artery -- frequently occurs on the aorta, the critical vessel which carries blood from the heart. Developing painlessly and often undetected, aneurysms can burst without warning and cause death. The current surgery to deal with aortic aneurysm is very complicated: doctors open the chest and replace the fragile portion of the artery with a graft from another one in the body. The new experimental device, basically a cylindrical patch that reinforces the weakened area, can be positioned in the aorta through a thin tube inserted into the groin area and guided up to the chest. If proven as effective as the surgery, the device, currently being tested on 150 patients in a four-year program, could be a major boon. "Any time you can avoid major surgery, you're better off," says TIME health reporter Janice Castro.