Left Atrial Appendage Thrombus

What is a Left Atrial Appendage Thrombus?

The left atrial appendage is a small chamber inside the left atrium. In people with a normal sinus rhythm, the atria contracts regularly, emptying all the blood in the atrium and the appendage. In someone with atrial fibrillation, however, the atria does not contract normally, which can increase the risk of developing a blood clot in the left atrial appendage as well as increase the risk of stroke. This is called left atrial appendage thrombus. Traditionally, this condition has been treated with either aspirin or anti-coagulation with warfarin.

Risk Factors

  • Atrial fibrillation 


Left atrial appendage thrombus does not cause any recognizable symptoms. However, if the thrombus becomes dislodged, it can increase your risk for a stroke.  

Diagnosis and Tests

  • Echocardiogram
  • Transesophageal echocardiogram 


Traditionally, aspirin or medical management with anti-coagulation with warfarin has been used to prevent left atrial appendage thrombus. Some patients do not tolerate warfarin and may be candidates for a new class of anti-coagulants for thrombus prevention called direct oral anticoagulants. There are also left atrial appendage closure devices that do not require medications after placement.