Atrial fibrillation is an irregular arrhythmia that originates in the atria (top chamber of the heart). AF is an extremely common arrhythmia worldwide—occurring in greater than 80% of the aging population. More than 5 million individuals in the United States have atrial fibrillation.
The left atrial appendage is a small, ear-shaped sac in the muscle wall of the left atrium. In atrial fibrillation, blood becomes stagnant in the appendage and becomes a source of clot formation. Clots from the left atrial appendage can embolize and result in strokes.
The annual risk of stroke from the left atrial appendage has a cumulative affect and increases almost linearly with time.
Historically the only method of preventing strokes from AF has been to place patients on anticoagulation with drugs such as Warfarin (Coumadin), Xarelto, Eliquis, or Pradaxa. Unfortunately these drugs have a significant risk of internal bleeding associated with them.
For decades a variety of surgical strategies have been explored to close the left atrial appendage and minimize the risk of stroke from AF. Most of these strategies, however, are quite invasive and have met with suboptimal clinical results. Over the last approximately ten years, two minimally invasive strategies have been successfully developed for closing the left atrial appendage and have demonstrated in clinical trials to successfully eliminate the need for blood thinners. They are the WATCHMAN™ LAAC Device and Lariat procedure.