Device-associated thrombus formation after left atrial appendage occlusion: A systematic review of events reported with the Watchman, the Amplatzer Cardiac Plug and the Amulet.

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Catheterization and cardiovascular interventions : official journal of the Society for Cardiac Angiography & Interventions


Administration, Oral; Anticoagulants; Atrial Appendage; Atrial Fibrillation; Cardiac Catheterization; Echocardiography, Transesophageal; Heparin, Low-Molecular-Weight; Humans; Incidence; Ischemic Attack, Transient; Risk Factors; Septal Occluder Device; Stroke; Thrombosis; Time Factors; Treatment Outcome; complication; left atrial appendage closure; thrombosis


OBJECTIVES: This study aimed to provide a systematic review of device-associated thrombosis (DAT) after left atrial appendage occlusion (LAAO) with the Watchman, Amplatzer Cardiac Plug, and Amulet devices.

BACKGROUND: DAT is known as a complication of LAAO but data about its clinical impact is scarce.

METHODS: A systematic review of studies evaluating the incidence, treatment and clinical implications of DAT from January 2008 to September 2015 was conducted.

RESULTS: A total of 30 studies describing DAT events were included in the analysis. The overall incidence of DAT was 3.9% (82 DAT for 2118 implanted devices). The median time from procedure to diagnosis of DAT was 1.5 months (IQR: 0-2.9). Most cases were diagnosed with transesophageal echocardiogram (TEE). The treatment consisted of low molecular weight heparin (LMWH) in 45.5% of cases, and oral anticoagulation (OAC) or other treatment modalities in 54.5%. Complete thrombus resolution was achieved in 95.0% of cases (100% with LMWH and 89.5% with OAC). Treatment duration varied greatly with a median treatment duration of 45 days (IQR: 14-135). Clinical events related to DAT consisted of neurologic events namely two transient ischemic attacks (2.4%) and four ischemic strokes (4.9%).

CONCLUSIONS: DAT is an infrequent complication of percutaneous LAAO. It occurs mainly early after the procedure and is associated with a low rate of neurological complications. In the majority of cases, diagnosis is made during follow-up imaging with TEE. Anticoagulation treatment seems to be safe and highly effective. Further studies are needed to evaluate the optimal management of DAT. © 2017 Wiley Periodicals, Inc.

Clinical Institute

Cardiovascular (Heart)