The AtriClip Gillinov-Cosgrove Left Atrial Appendage (LAA) Exclusion system, developed by Cleveland Clinic heart surgeons, has been approved by the Food and Drug Administration and is expected to be available on a broad scale this fall. The LAA is a small, hollow sac-like structure that is attached to the hearts left atrium (an upper chamber). In patients who have atrial fibrillation (AF), blood can pool in the LAA and clots can form and migrate to other parts of the body. Cleveland Clinic heart surgeon Marc Gillinov, MD, explains that the AtriClip is implanted from the outside of the heart and eliminates the flow of blood between the LAA and the left atrium. For many years, doctors have sewn up the entrance to the LAA during surgery, but that had a fairly high failure rate, Dr. Gillinov says. The AtriClip has been approved for use in patients undergoing open-heart surgery and who also have AF or are at strong risk for developing AF.