Feasibility of Left Atrial Appendage Occlusion in Left Atrial Appendage Thrombus: A Systematic Review

Objectives: This study aimed to investigate the feasibility and safety of left atrial appendage occlusion (LAAO) procedures in patients with persistent left atrial appendage (LAA) thrombus. Background: The left atrial appendage (LAA) is the most common site of thrombus formation in patients with nonvalvular atrial fibrillation (AF). Oral anticoagulation (OAC) is used to prevent and treat AF-related thrombus. However, a significant proportion of patients may not be eligible for long-term OAC therapy. In many cases, OAC may fail to resolve the thrombus. Left atrial appendage occlusion (LAAO) may be a potential option in such cases. Major LAAO studies have excluded patients with LAA thrombus, and it is not known whether LAAO procedures in the presence of LAA thrombus is feasible and safe. Methods: This was a systematic review of patient-level data of all published cases of LAAO in the presence of LAA thrombus. Results: There was a total of 58 patients included in the study. Most of the patients had a distally located thrombus in the LAA. All cases underwent successful implantation of LAAO devices with some procedural modifications. Amulet was the most commonly used device (50%). A cerebral protection device was used in 17 (29%) patients, and procedural transesophageal echocardiography was used in most of the cases. One stroke (1.7%) and 2 (3.4%) device-related thromboses were noted during the mean follow-up of 3.4 ± 7 months. Conclusions: Percutaneous LAAO procedures appear to be feasible in patients with a distally located persistent LAA thrombus when performed by experienced operators with some technical modifications. Further studies are required to determine the long-term safety and efficacy of this approach.