Early Device-Related Thrombus After LAAO With WATCHMAN Device
An 80-year-old male patient with atrial fibrillation and recurrent gastrointestinal bleeding underwent a percutaneous LAA device closure due to increased risk for bleeding complications. A TEE was done on the 45th day for surveillance per protocol. The TEE was suspicious for device thrombus on two-dimensional images (B-C). Three-dimensional imaging readily confirmed the device thrombus along the warfarin ridge (D).
Percutaneous LAA closure is increasingly performed in patients with contraindications to anticoagulation to reduce the thromboembolic risk. However, at a reported incidence of 2-8%, device-related thrombosis is a growing concern, with up to 4 times increased stroke risk. Risk factors for device-related thrombosis can be either patient-specific (large LAA diameter, permanent atrial fibrillation, high CHA2DS2-VASc score, reduced ejection fraction, vascular disease, or prior stroke/transient ischemic attack) or device-specific (deep implantation or larger mean device size).
In the PROTECT-AF (WATCHMAN Left Atrial Appendage System for Embolic Protection in Patients With Atrial Fibrillation) and PREVAIL (Watchman LAA Closure Device in Patients With Atrial Fibrillation Versus Long Term Warfarin Therapy) studies, TEE was performed at 45 days and 6 and 12 months to ensure adequate seal and determine the duration of anticoagulation. A detailed TEE with multiplanar imaging should be done to specifically confirm the device position at or just distal to the orifice of the LAA, the span to cover the entire ostium, and a fully sealed LAA with a peri-device leak <5 mm (C, E-F). In case of a peri-device leak >5 mm, continued anticoagulation or interventional procedures to plug the leak may be considered.
In our case, the device was positioned appropriately with a leak <5 mm; however, the patient had multiple risk factors for device-related thrombosis and was not on anticoagulation due to recurrent gastrointestinal bleeding. This case illustrates the continued risk of thrombus despite LAA closure in high-risk patients. Judicious surveillance strategy and careful assessment of the appendage is important while performing TEE post LAA device closure.
Date: August 25, 2020
Keywords: Arrhythmias, Cardiac, Cardiac Imaging Techniques