Late-Onset Device Related Thrombosis After Left Atrial Appendage Occlusion and Spleen Systemic Embolism: A Case Report.

Device-related thrombosis (DRT) is a rare but serious complication following left atrial appendage occlusion (LAAO). A 58-year-old woman with permanent atrial fibrillation (AF), multiple comorbidities, and a history of transient ischemic attack despite anticoagulation underwent LAAO in December 2023. Initially prescribed oral anticoagulants, she discontinued them due to side effects and switched to single antiplatelet therapy. Nearly 1-year postprocedure, a thrombus was detected on the LAAO device. Despite heparin infusion, she developed systemic embolism, resulting in splenic infarction and subsequent splenectomy. She was discharged on warfarin, but a persistent thrombus was noted on a 1-month transesophageal echocardiogram, necessitating continued warfarin therapy and serial follow-ups. The prediction, detection, and management of DRT remain challenging and uncertain due to a lack of robust evidence-based protocols. Balancing bleeding and thrombotic risks, especially in frail patients, is complex. While LAAO is an effective stroke prevention strategy for AF patients, the risks of DRT should not be overlooked. Further research is essential to refine DRT management protocols.