left atrial appendage; left atrial auricle (LAA)

Introduction

embryonic remnant of the original left atrium

Structure

• a long, tubular, trabeculated structure
• in continuity with the left atrial cavity

Pathology

• predisposed to in-situ thrombus formation
• > 90% of atrial thrombi in patients with non-valvular atrial fibrillation are believed to originate in the left atrial appendage
• left atrial appendage closure is an investigational procedure to prevent thromboembolism in atrial fibrillation

More general terms

• atrial auricle

Additional terms

• left atrial appendage closure (Watchman device, Lariat device)