Background: Left atrial (LA) mural thrombus is a rare but serious complication after mitral valve (MV) repair, particularly with postoperative atrial fibrillation (POAF), LA enlargement, and altered hemodynamics, even after left atrial appendage (LAA) closure and anticoagulation.
Case Summary: A 51-year-old man developed a giant LA mural thrombus (5.6 × 2.95 cm) four weeks after MV annuloplasty with Physio II ring, CABG × 3, and AtriClip LAA closure, despite therapeutic apixaban for new-onset POAF. Multidisciplinary heart team discussion favored conservative management over high-risk early re-sternotomy.
Discussion: The patient was bridged from intravenous heparin to warfarin (target INR 2.5–3.5, initially higher). Serial TEE and CT imaging demonstrated progressive resolution, with complete thrombus disappearance at eight months without embolization, major bleeding, or reoperation.
Keywords: Left atrial mural thrombus; Giant left atrial thrombus; Mitral valve repair/annuloplasty; Coronary artery bypass grafting; Left atrial appendage clip/closure; Direct oral anticoagulant; Apixaban; Warfarin; Conservative management; Serial imaging; Case report; Multidisciplinary heart team
