Arrhythmias & electrophysiologyResearch article
Left Atrial Appendage Thrombosis in Patients With Atrial Fibrillation
- histologic and immunohistochemical analysis of left atrial appendage (LAA) specimens from participants in the Left Atrial Appendage Occlusion Study (LAAOS) III trial
Authors' conclusion
Despite only a brief interruption of anticoagulant therapy before surgery, fibrin microthrombi and endocardial fibrin deposition are common in LAA. These findings suggest a persistent local thrombogenic potential during perioperative interruption of anticoagulation.
Study context
- Population
- Patients with atrial fibrillation in the LAAOS III trial who underwent surgical left atrial appendage occlusionLAA specimens from participants in the LAAOS III trial
- Participants
- 57 patients
Main finding
As reported in the abstract
Large luminal thrombus
LAA with a large thrombus in its lumen
One
Further findings
Microthrombi (red blood cells and leukocytes, staining for fibrin)
- LAA specimens with microthrombi
- 21 of 57 (37%)
- Microthrombi localized in the trabecular crypts and stained for von Willebrand factor
Endocardial fibrin layer with adherent leukocytes staining for tissue factor
- Specimens with a layer of fibrin on the endocardial wall
- 58%
Original publication
Left Atrial Appendage Thrombosis in Patients With Atrial Fibrillation. JACC Clin Electrophysiol. Published 1 September 2026. doi:10.1016/j.jacep.2026.07.030
Summarised from the published abstract; every number is checked against it