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Updated: May 12, 2026
The WATCHMAN Left Atrial Appendage Closure Device for Atrial Fibrillation
Published on: February 28, 2012
Massive late device-related thrombus with watchman FLX left atrial appendage closure device two years after
Danielle Shields1, Bhavya Varma2, Daniel Bamira2
1Department of Internal Medicine, NYU Langone Health, New York, NY, USA.
Oral anticoagulation (OAC) remains the primary means of stroke prevention in patients with atrial fibrillation (AF). However, there are patients at greater risk of bleeding or who have experienced major bleeding, whereby long term OAC is relatively contraindicated. Additionally, up to 55% of eligible AF patients do not utilize OAC. Thus, transcatheter left atrial appendage occlusion devices (LAAOD) present an attractive alternative to mitigate stroke risk. Randomized trials have demonstrated the noninferiority of LAAOD to OAC in reducing stroke risk. However, treatment with LAAODs presents its own risks, including the risk of device-related thrombus (DRT). In this report, we describe an unusual case of a patient with a small DRT initially identified on transesophageal echocardiography (TEE) 6 weeks after implantation of a Watchman FLX (Boston Scientific, Marlborough, MA, USA) LAAOD that was appropriately treated and resolved on TEE 6 months after implantation. However, a massive late DRT recurred 2 years after implantation. This case highlights the importance of continued device monitoring for unfavorable evolution of DRT beyond the currently recommended 45-day to 1-year monitoring period, and especially after suspected thrombus resolution. Furthermore, it underlines the importance of developing newer generation LAAOD that reduces DRT risk.
Oral anticoagulation (OAC) remains the primary means of stroke prevention in patients with atrial fibrillation (AF). However, there are patients at greater risk of bleeding or who have experienced major bleeding, whereby long term OAC is relatively contraindicated. Additionally, up to 55% of eligible AF patients do not utilize OAC. Thus, transcatheter left atrial appendage occlusion devices (LAAOD) present an attractive alternative to mitigate stroke risk. Randomized trials have demonstrated the noninferiority of LAAOD to OAC in reducing stroke risk. However, treatment with LAAODs presents its own risks, including the risk of device-related thrombus (DRT). In this report, we describe an unusual case of a patient with a small DRT initially identified on transesophageal echocardiography (TEE) 6 weeks after implantation of a Watchman FLX (Boston Scientific, Marlborough, MA, USA) LAAOD that was appropriately treated and resolved on TEE 6 months after implantation. However, a massive late DRT recurred 2 years after implantation. This case highlights the importance of continued device monitoring for unfavorable evolution of DRT beyond the currently recommended 45-day to 1-year monitoring period, and especially after suspected thrombus resolution. Furthermore, it underlines the importance of developing newer generation LAAOD that reduces DRT risk.
Learning Objective:
Left atrial appendage occlusion devices can mitigate stroke risk in atrial fibrillation patients with contraindications to oral anticoagulation. However, these devices present with their own risks, including the risk of device-related thrombus (DRT). This case highlights the importance of continued device monitoring for unfavorable evolution of DRT beyond the recommended 45-day to 1-year monitoring period.
