Which structure is associated with thrombus in patients with atrial fibrillation?

Which structure is associated with thrombus in patients with atrial fibrillation?

• A. The left atrial appendage
• B. The right atrial appendage
• C. The right ventricle apex
• D. The left ventricle apex

Answer: (A)

Atrial fibrillation causes irregular, ineffective atrial contractions that lead to blood stasis in the left atrium, with the left atrial appendage being a common pocket where this pooling occurs. Because of this stasis, thrombi frequently form there, and embolization from the left atrial appendage can travel to the brain and cause stroke. The other sites are less typical for thrombus in atrial fibrillation: the right atrial appendage is not the usual source in this setting, and thrombi in the ventricles (left or right) generally relate to myocardial infarction or cardiomyopathy rather than AF-related stasis.

Atrial fibrillation causes irregular, ineffective atrial contractions that lead to blood stasis in the left atrium, with the left atrial appendage being a common pocket where this pooling occurs. Because of this stasis, thrombi frequently form there, and embolization from the left atrial appendage can travel to the brain and cause stroke. The other sites are less typical for thrombus in atrial fibrillation: the right atrial appendage is not the usual source in this setting, and thrombi in the ventricles (left or right) generally relate to myocardial infarction or cardiomyopathy rather than AF-related stasis.